U.S. patent application number 11/930683 was filed with the patent office on 2008-08-28 for internal combustion engine and working cycle.
Invention is credited to Clyde C. Bryant.
Application Number | 20080208434 11/930683 |
Document ID | / |
Family ID | 35730753 |
Filed Date | 2008-08-28 |
United States Patent
Application |
20080208434 |
Kind Code |
A1 |
Bryant; Clyde C. |
August 28, 2008 |
Internal Combustion Engine and Working Cycle
Abstract
The invention is concerned with a method of deriving mechanical
work from a combustion gas in internal combustion engines and
reciprocating internal combustion engines for carrying out the
method. The invention includes methods and apparatuses for managing
combustion charge densities, temperatures, pressures and turbulence
in order to produce a true mastery within the power cylinder in
order to increase fuel economy, power, and torque while minimizing.
polluting emissions. In its preferred embodiments, the method
includes the steps of (i) producing an air charge, (ii) controlling
the temperature, density and pressure of the air charge, (iii)
transferring the air charge to a power cylinder of the engine such
that an air charge having a weight and density selected from a
range of weight and density levels ranging from below atmospheric
weight and density to heavier-than-atmospheric weight and density
is introduced into the power cylinder, and (iv) then compressing
the air charge at a lower-than-normal compression ratio, (v)
causing a pre-determined quantity of charge-air and fuel to produce
a combustible mixture, (vi) causing the mixture to be ignited
within the power cylinder and (vii) allowing the combustion gas to
expand against a piston operable in the power cylinders with the
expansion ratio of the power cylinders being substantially greater
than the compression ratio of the power cylinders of the engine. In
addition to other advantages, the invented method is capable of
producing mean effective cylinder pressures ranging from
lower-than-normal to higher-than-normal. In the preferred
embodiments, the mean effective cylinder pressure is selectively
variable (and selectively varied) throughout the mentioned range
during the operation of the engine. In an alternate embodiment
related to constant speed-constant load operation, the mean
effective cylinder pressure is selected from the range and the
engine is configured, in accordance with the present invention,
such that the mean effective cylinder pressure range is limited,
being varied only in the amount required for producing the power,
torque and speed of the duty cycle for which the engine is
designed.
Inventors: |
Bryant; Clyde C.;
(Alpharetta, GA) |
Correspondence
Address: |
WOMBLE CARLYLE SANDRIDGE & RICE, PLLC
ATTN: PATENT DOCKETING 32ND FLOOR, P.O. BOX 7037
ATLANTA
GA
30357-0037
US
|
Family ID: |
35730753 |
Appl. No.: |
11/930683 |
Filed: |
October 31, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11236765 |
Sep 27, 2005 |
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11930683 |
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10996695 |
Nov 23, 2004 |
7222614 |
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11236765 |
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09632739 |
Aug 4, 2000 |
7281527 |
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10996695 |
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08863103 |
May 23, 1997 |
6279550 |
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09632739 |
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08841488 |
Apr 23, 1997 |
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08863103 |
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60022102 |
Jul 17, 1996 |
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60023460 |
Aug 6, 1996 |
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60040630 |
Mar 7, 1997 |
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60029260 |
Oct 25, 1996 |
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Current U.S.
Class: |
701/103 ;
123/568.11; 123/90.15 |
Current CPC
Class: |
Y02T 10/146 20130101;
F01L 13/0015 20130101; F01L 1/465 20130101; F02B 29/0418 20130101;
Y02T 10/12 20130101; F01L 1/46 20130101; Y02T 10/144 20130101; F02B
33/26 20130101; F01L 1/053 20130101; F02B 33/06 20130101; F02B
37/16 20130101; F02B 29/0412 20130101; F02B 29/0493 20130101; F01L
1/146 20130101; F02B 39/10 20130101; F02B 33/38 20130101; F02B
37/04 20130101; F01L 1/26 20130101; F02B 33/44 20130101 |
Class at
Publication: |
701/103 ;
123/568.11; 123/90.15 |
International
Class: |
F02D 41/00 20060101
F02D041/00 |
Claims
1. A method of operating a four-stroke internal combustion engine
including at least one cylinder and a piston slidable in the
cylinder and moving through a plurality of power cycles each
involving an intake stroke, a compression stroke, an expansion
stroke and an exhaust stroke, the method comprising: supplying
pressurized air from an intake manifold to at least one air intake
port of a chamber in the cylinder; selectively operating at least
one air intake valve to open at least one air intake port to allow
pressurized air to flow between the chamber and the intake manifold
substantially during a majority portion of a compression stroke of
the piston; and operably controlling a fuel supply system to inject
fuel into the chamber after the at least one intake valve is
closed.
2. The method of claim 1, wherein the pressurized air is cooled
before being supplied to the air intake port.
3. The method of claim 2, wherein said selectively operating
includes operating a variable intake valve closing mechanism to
keep at least one intake valve open.
4. The method of claim 2, wherein the variable intake valve closing
mechanism is operated electronically.
5. The method of claim 2, wherein the selective operation of at
least one air intake valve is based on at least one engine
condition.
6. The method of claim 2, wherein said selectively operating
includes operating an intake valve to remain open for a portion of
a second half of the compression stroke of the piston.
7. The method of claim 2, wherein said operably controlling a fuel
supply system includes operating a fuel injector assembly
electronically.
8. The method of claim 1, wherein selectively operating includes
selectively operating at least one valve to open a single intake
port.
9. The method of claim 1, further comprising, at or after an intake
valve is closed, selectively operating at least one intake valve to
open at least one intake port through which additional pressurized
air is injected into the chamber.
10. The method of claim 1, further comprising: imparting rotational
movement to a first turbine and a first compressor of a first
turbocharger with exhaust air flowing from an exhaust port of the
cylinder; compressing air drawn from atmosphere with the first
compressor; compressing air received from the first compressor with
a second compressor; and supplying pressurized air from the second
compressor to the intake manifold.
11. The method of claim 10, wherein fuel is injected during a
combustion stroke.
12. The method of claim 11, wherein fuel injection begins during
the compression stroke.
13. The method of claim 10, wherein said selectively operating
includes operating a variable intake valve closing mechanism to
interrupt cyclical movement of at least one intake valve.
14. The method of claim 10, wherein the selective operation of at
least one air intake valve is based on at least one engine
condition.
15. The method of claim 10, wherein said selectively operating
includes operating at least one air intake valve to remain open for
a portion of a second half of the compression stroke of the
piston.
16. The method of claim 10, wherein said controllably operating a
fuel supply system includes operating a fuel injector assembly
electronically.
17. The method of claim 10, wherein the air is cooled prior to
supplying it to the at least one air intake port.
18. The method of claim 10, wherein at or after a first intake
valve is closed a secondary charge of pressurized air is injected
into the chamber.
19. The method of claim 18, wherein at least part of the secondary
charge is injected through the first air intake port.
20. The method of claim 18, wherein at least a part of the
secondary charge is injected through a second air intake port.
21. The method of claim 18, wherein the secondary charge is cooled
prior to injection.
22. The method of claim 1, further including pressurizing air and
supplying said air to the intake manifold of the engine.
23. The method of claim 22 wherein said selectively operating
includes maintaining fluid communication between the chamber and
the intake manifold during a portion of an intake stroke and
through at least a majority of the compression stroke.
24. The method of claim 23 further including supplying a
pressurized fuel directly to the chamber during a portion of a
combustion stroke.
25. The method of claim 24, further including supplying the
pressurized fuel during a portion of the compression stroke.
26. The method of claim 25, wherein supplying the pressurized fuel
includes supplying a pilot injection at a predetermined crank angle
before a main injection.
27. The method of claim 26, wherein said main injection begins
during the compression stroke.
28. The method of claim 22, wherein said pressurizing includes a
first stage of pressurization and a second stage of
pressurization.
29. The method of claim 28, further including cooling air between
said first stage of pressurization and said second stage of
pressurization.
30. The method of claim 22, further including cooling the
pressurized air prior to supplying said air to the intake
manifold.
31. The method of claim 23, wherein said pressurizing includes a
first stage of pressurization and a second stage of
pressurization.
32. The method of claim 31, further including cooling air between
said first stage of pressurization and said second stage of
pressurization.
33. The method of claim 22, wherein pressurized air is supplied to
the chamber in two charges.
34. The method of claim 33, wherein a primary charge is supplied to
the chamber through a port controlled by an intake valve.
35. The method of claim 34, wherein a secondary charge is injected
into the chamber during the compression stroke, at or after the
intake valve is closed.
36. The method of claim 35, wherein the secondary charge is
injected through a second port.
37. The method of claim 22, wherein said pressurizing includes
pressurizing air to a ratio of at least 4:1 with respect to
atmospheric pressure.
38. The method of claim 37, further including: maintaining fluid
communication between the chamber and the intake manifold during an
intake stroke and a majority of a compression stroke; and supplying
a fuel to the chamber during at least a portion of the remaining
compression stroke.
39. The method of claim 38, wherein said majority is greater than
90 degrees crank angle after bottom dead center.
40. The method of claim 38, wherein said supplying fuel includes
injecting a first portion of fuel a predetermined period prior to
injecting a second portion of fuel.
41. The method of claim 40, wherein said injecting the second
portion of fuel begins during the compression stroke and terminates
during a combustion stroke.
42. The method of claim 38, further including cooling the air prior
to supplying the air to the chamber.
43. The method of claim 30, including managing the pre-combustion
conditions in the chamber of the engine.
44. The method of claim 30, further comprising controlling each of
the characteristics of: turbulence in the chamber; density of the
cooled, pressurized air; pressure of the cooled, pressurized air;
temperature of the cooled, pressurized air; mean cylinder pressure
within the chamber; and peak pressure within the chamber.
45. The method of claim 1, wherein supplying pressurized air
comprises supplying a pressurized mixture of air and recirculated
exhaust gas from an intake manifold to an air intake port of a
chamber in the cylinder, and wherein selectively operating
comprises selectively operating an air intake valve to open the air
intake port to allow the pressurized mixture of air and exhaust gas
to flow between the chamber and the intake manifold substantially
during a majority portion of a compression stroke of the
piston.
46. The method of claim 22, wherein said pressurizing includes
subjecting air to at least one stage of compression.
47. The method of claim 46, wherein said pressurizing includes
subjecting air to two or more stages of compression.
48. The method of claim 47, wherein said pressurizing includes
subjecting air to more than two stages of compression.
49. The method of claim 30, including providing, through motion of
the piston, extra burn time for the combustion process.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No.
11/236,765, filed Sep. 27, 2005; which is a continuation of
application Ser. No. 10/996,695, filed Nov. 23, 2004; which is a
continuation of application Ser. No. 09/632,739, filed Aug. 4,
2000, now U.S. Pat. No. 7,281,527; which is a continuation of
application Ser. No. 08/863,103, filed May 23, 1997, now U.S. Pat.
No. 6,279,550; which application claims the benefit of provisional
application Nos. 60/022,102, filed Jul. 17, 1996; 60/023,460, filed
Aug. 6, 1996; 60/029,260, filed Oct. 25, 1996; and 60/040,630,
filed Mar. 7, 1997, and which is a continuation-in-part of
application Ser. No. 08/841,488, filed Apr. 23, 1997, now
abandoned.
INCORPORATION BY REFERENCE
[0002] The specification of application Ser. No. 08/863,103, filed
May 23, 1997 (U.S. Pat. No. 6,279,550) is incorporated herein in
its entirety, by this reference.
BACKGROUND OF INVENTION
[0003] It is well known that as the expansion ratio of an internal
combustion engine is increased, more energy is extracted from the
combustion gases and converted to kinetic energy and the
thermodynamic efficiency of the engine increases. It is further
understood that increasing air charge density increases both power
and fuel economy due to further thermodynamic improvements. The
objectives for an efficient engine are to provide a high-density
charge, begin combustion at maximum density and then expand the
gases as far as possible against a piston.
[0004] Conventional engines have the same compression and expansion
ratios, the former being limited in spark-ignited engines by the
octane rating of the fuel used. Furthermore, since in these engines
the exploded gases can be expanded only to the extent of the
compression ratio of the engine, there is generally substantial
heat and pressure in the exploding cylinder which is dumped into
the atmosphere at the time the exhaust valve opens resulting in a
waste of energy and producing unnecessarily high polluting
emissions.
[0005] Many attempts have been made to reduce the compression ratio
and to extend the expansion process in internal combustion engines
to increase their thermodynamic efficiency, the most notable one
being the "Miller" Cycle engine, developed in 1947.
[0006] Unlike a conventional 4-stroke cycle engine, where the
compression ratio equals the expansion ratio in any given
combustion cycle, the Miller Cycle engine is a variant, in that the
parity is altered intentionally. The Miller Cycle uses an ancillary
compressor to supply an air charge, introducing the charge on the
intake stroke of the piston and then closing the intake valve
before the piston reaches the end of the inlet stroke. From this
point the gases in the cylinder are expanded to the maximum
cylinder volume and then compressed from that point as in the
normal cycle. The compression ratio is then established by the
volume of the cylinder at the point that the inlet valve closed,
being divided by the volume of the combustion chamber. On the
compression stroke, no actual compression starts until the piston
reaches the point the intake valve closed during the intake stroke,
thus producing a lower-than-normal compression ratio. The expansion
ratio is calculated by dividing the swept volume of the cylinder by
the volume of the combustion chamber, resulting in a
more-complete-expansion, since the expansion ratio is greater than
the compression ratio of the engine.
[0007] In the 2-stroke engine the Miller Cycle holds the exhaust
valve open through the first 20% or so of the compression stroke in
order to reduce the compression ratio of the engine. In this case
the expansion ratio is probably still lower than the compression
ratio since the expansion ratio is never as large as the
compression ratio in conventional 2-stroke engines.
[0008] The advantage of this cycle is the possibility of obtaining
an efficiency higher than could be obtained with an expansion ratio
equal to the compression ratio. The disadvantage is that the Miller
Cycle has a mean effective pressure lower than the conventional
arrangement with the same maximum pressure, but with no appreciable
improvements in emissions characteristics.
[0009] The Miller Cycle is practical for engines that are not
frequently operated at light-loads, because at light-load operation
the mean cylinder pressure during the expansion stroke tends to be
near to, or even lower than, the friction mean pressure. Under such
circumstances the more-complete-expansion portion of the cycle may
involve a net loss rather than a gain in efficiency.
[0010] This type of engine may be used to advantage where maximum
cylinder pressure is limited by detonation or stress considerations
and where a sacrifice of specific output is permissible in order to
achieve the best possible fuel economy. The cycle is suitable only
for engines that operate most of the time under conditions of high
mechanical efficiency, that is, at relatively low piston speeds and
near full load.
SUMMARY OF THE INVENTION
[0011] Briefly described, the present invention comprises an
internal combustion engine system (including methods and
apparatuses) for managing combustion charge densities,
temperatures, pressures and turbulence in order to produce a true
mastery within the power cylinder in order to increase fuel
economy, power, and torque while minimizing polluting emissions. In
its preferred embodiments, the method includes the steps of (i)
producing an air charge, (ii) controlling the temperature, density
and pressure of the air charge, (iii) transferring the air charge
to a power cylinder of the engine such that an air charge having a
weight and density selected from a range of weight and density
levels ranging from atmospheric weight and density to a
heavier-than-atmospheric weight and density is introduced into the
power cylinder, and (iv) then compressing the air charge at a
lower-than-normal compression ratio, (v) causing a pre-determined
quantity of charge-air and fuel to produce a combustible mixture,
(vi) causing the mixture to be ignited within the power cylinder,
and (vii) allowing the combustion gas to expand against a piston
operable in the power cylinder with the expansion ratio of the
power cylinder being substantially greater than the compression
ratio of the power cylinders of the engine. In addition to other
advantages, the invented method is capable of producing mean
effective [cylinder] pressures ("mep") in a range ranging from
lower-than-normal to higher-than-normal. In the preferred
embodiments, the mean effective cylinder pressure is selectively
variable (and selectively varied) throughout the mentioned range
during the operation of the engine. In an alternate embodiment
related to constant speed-constant load operation, the mean
effective cylinder pressure is selected from the range and the
engine is configured, in accordance with the present invention,
such that the mean effective cylinder pressure range is limited,
being varied only in the amount required for producing the power,
torque and speed of the duty cycle for which the engine is
designed.
[0012] In its preferred embodiments, the apparatus of the present
invention provides a reciprocating internal combustion engine with
at least one ancillary compressor for compressing an air charge, an
intercooler through which the compressed air can be directed for
cooling, power cylinders in which the combustion gas is ignited and
expanded, a piston operable in each power cylinder and connected to
a crankshaft by a connecting link for rotating the crankshaft in
response to reciprocation of each piston, a transfer conduit
communicating the compressor outlet to a control valve and to the
intercooler, a transfer manifold communicating the intercooler with
the power cylinders through which manifold the compressed charge is
transferred to enter the power cylinders, an intake valve
controlling admission of the compressed charge from the transfer
manifold to said power cylinders, and an exhaust valve controlling
discharge of the exhaust gases from said power cylinders. For the
4-stroke engine of this invention, the intake valves of the power
cylinders are timed to operate such that charge air which is equal
to or heavier than normal can be maintained within the transfer
manifold when required and introduced into the power cylinder
during the intake stroke with the intake valve closing at a point
substantially before piston bottom dead center position or,
alternatively, with the intake valve closing at some point during
the compression stroke, to provide a low compression ratio. In some
designs another intake valve can open and close quickly after the
piston has reached the point the first intake valve closed in order
to inject a temperature adjusted high pressure secondary air charge
still at such a time that the compression ratio of the engine will
be less than the expansion ratio, and so that ignition can commence
at substantially maximum charge density. The 2-stroke engine of
this invention differs in that the intake valves of the power
cylinders are timed to operate such that an air charge is
maintained within the transfer manifold and introduced into the
power cylinder during the scavenging-compression (the 2nd) stroke
at such a time that the power cylinder has been scavenged by low
pressure air and the exhaust valve has closed, establishing that
the compression ratio of the engine will be less than the expansion
ratio of the power cylinders. Means are provided for causing fuel
to be mixed with the air charge to produce a combustible gas, the
combustion chambers of the power cylinders are sized with respect
to the displaced volume of the power cylinder such that the
exploded combustion gas can be expanded to a volume substantially
greater than the compression ratio of the power cylinder of the
engine.
[0013] The chief advantages of the present invention over existing
internal combustion engines are that it provides a compression
ratio lower than the expansion ratio of the engine, and provides,
selectively, a mean effective cylinder pressure higher than the
conventional engine arrangement with the same or lower maximum
cylinder pressure than that of prior art engines.
[0014] This allows greater fuel economy, and production of greater
power and torque at all RPM, with low polluting emissions. Because
charge densities, temperatures and pressures are managed,
light-load operation is practical even for extended periods, with
no sacrifice of fuel economy. The new working cycle is applicable
to 2-stroke or 4-stroke engines, both spark-ignited and
compression-ignited. For spark-ignited engines the weight of the
charge can be greatly increased without the usual problems of high
peak temperatures and pressures with the usual attendant problem of
combustion detonation and pre-ignition. For compression-ignited
engines, the heavier, cooler, more turbulent charge provides low
peak cylinder pressure for a given expansion ratio and allows
richer, smoke-limited air-fuel ratio giving increased power with
lower particulate and NO.sub.x emissions. Compression work is
reduced due to reduced heat transfer during the compression
process. Engine durability is improved because of an overall cooler
working cycle and a cooler than normal exhaust. It also provides a
means of regenerative braking for storing energy for subsequent
positive power cycles without compression work and for transient or
"burst" power which further increases the overall efficiency of the
engine.
[0015] All of the objects, features and advantages of the present
invention cannot be briefly stated in this summary, but will be
understood by reference to the following specifications and the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Embodiments of internal combustion engines according to the
invention will now be described, by way of example, with reference
to the accompanying drawings, in which:
[0017] FIG. 1 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 4-stroke cycle, and
representing a first embodiment of the apparatus of the present
invention from which a first method of operation can be performed
and will be described. Among its other components, this embodiment
is seen as having one ancillary compressor, a cooling system and
valves to control charge pressures, density and temperature.
[0018] FIG. 2 is a schematic drawing of a six cylinder internal
combustion engine, similar to the engine of FIG. 1, operating in a
4-stroke cycle, and representing a second embodiment of the
apparatus of the present invention from which a second method of
operation can be performed and will be described. Among its other
components, this embodiment is seen as having two compressors,
three intercoolers, four control valves, dual air paths for both
the primary and the ancillary compressors, dual manifolds and
showing a means of controlling charge-air pressures, density and
temperatures.
[0019] FIG. 3 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 4-stroke cycle, and
representing a third embodiment of the apparatus of the present
invention from which a third method of operation can be performed
and will be described.
[0020] FIG. 4 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 4-stroke cycle, and
representing a fourth embodiment of the apparatus of the present
invention from which a fourth method of operation can be performed
and will be described. Among its other components, this embodiment
is seen as having an ancillary compressor, with two charge-air
intake ducts and dual intake air routes, one of which is low
pressure and one which is high pressure, and both leading to the
same power cylinder, a cooling system and valves for controlling
charge-air pressures, density and temperature and an ancillary
atmospheric air intake system.
[0021] FIG. 4-B is a perspective view (with portions in
cross-section) of an engine similar to the engine of FIG. 4 with
the exception that there is only one atmospheric air intake which
supplies charge-air to the power cylinders at two different
pressure levels.
[0022] FIG. 4-C is a schematic view of an exhaust and an air intake
system of an engine showing a means of re-burning exhaust gases in
order to reduce polluting emissions.
[0023] FIG. 5 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 4-stroke cycle, and
representing a fifth embodiment of the apparatus of the present
invention from which a fifth method of operation can be performed
and will be described. Among its other components, this embodiment
is seen as having one atmospheric air intake, an ancillary
compressor with two charge-air routes, one of which is low pressure
and which has two optional routes, and one which is high pressure,
both leading to the same power cylinder, and control valving means
and air coolers for varying charge densities, pressures and
temperatures in the combustion chamber of the engine.
[0024] FIG. 6 is a part sectional view through one power cylinder
of the 4-stroke engine of FIG. 4, FIG. 4-B, FIG. 5, FIG. 7 or FIG.
33 at the intake valves showing an alternative method (adaptable to
other embodiments of the present invention) of preventing
charge-air back flow and of automatically adjusting the charge
pressure-ratio of the cylinder during the air charging process.
[0025] FIG. 7 is a schematic drawing of a six cylinder, 4-stroke
engine representing yet another embodiment of the apparatus of the
present invention, from which yet another method of operation can
be performed and will be described, and depicting three alternative
systems (two in phantom lines) of inducting a low pressure primary
air charge. Among its other components, this embodiment is seen as
having three air coolers and dual manifolds and the means of
controlling the temperature, density and pressure of the charge by
an engine control module and by valving variations.
[0026] FIG. 8 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine, operating in a 2-stroke cycle, and
representing a first 2-stroke embodiment of the apparatus of the
present invention from which still another method of operation can
be performed and will be described. Among its other components,
this embodiment is seen as having a primary and an ancillary
compressor, a cooling system and conduits and valves to adjust
charge density, temperature and pressure according to the
invention.
[0027] FIG. 9 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 2-stroke cycle, and
representing a second 2-stroke embodiment of the apparatus of the
present invention from which still another method of operation of
can be performed and will be described. Among its other components,
this embodiment is seen as having one atmospheric air intake, a
primary and an ancillary compressor, with two charge-air routes,
one of which is low pressure which has alternate routes, and one of
which is high pressure, and both leading to the same power
cylinder, and control valving means and air coolers for varying
charge densities, pressures and temperatures in the combustion
chamber of the engine.
[0028] FIG. 9-B is a schematic drawing of a six cylinder, 2-stroke
engine representing yet another embodiment of the apparatus of the
present invention, from which yet another method of operation can
be performed and will be described, and depicting two alternative
systems (one in phantom lines) of inducting a low pressure primary
air charge. Among its other components, this embodiment is seen as
having three air coolers and dual manifolds and the means of
controlling the temperature, density and pressure of the charge by
an engine control module and by valving variations.
[0029] FIG. 10 is a part sectional view through one power cylinder
of the 2-stroke engine of FIG. 9, at the intake valves, showing an
alternative method (adaptable to other embodiments of the present
invention) of preventing charge-air back flow during high pressure
air charging and showing a pressure balanced valve having a pumped
oil/air cooling system.
[0030] FIG. 11 is a perspective view (with portions in
cross-section) of the cylinder block and head of a six cylinder
internal combustion engine operating in a 2-stroke cycle, and
representing a third 2-stroke embodiment of the apparatus of the
present invention from which still another method of operation of
can be performed and will be described. Among its other components,
this embodiment is seen as having a primary and an ancillary
compressor, a cooling system and conduits and valves to adjust
charge density, temperature and pressure and having a single air
intake runner for each power cylinder with at least two intake
valves arranged in such a manner that one intake valve can operate
with timing independent of the other intake valve.
[0031] FIG. 12 is a pressure-volume diagram comparing the cycle of
the engine of this invention with that of a high-speed diesel
engine.
[0032] FIG. 13 is a chart showing improvements possible in the
engine of this invention in effective compression ratios, peak
temperatures and pressures, charge densities and expansion ratios,
in comparison with a popular heavy-duty 2-stroke diesel engine.
[0033] FIG. 14 is a chart showing improvements possible in the
engine of this invention in effective compression ratios, peak
temperatures and pressures, charge densities and expansion ratios,
in comparison with a popular heavy-duty, 4-stroke diesel
engine.
[0034] FIG. 15 is a schematic drawing of suggested operating
parameters for operation of the engines, both 2-stroke and
4-stroke, of FIGS. 5-7 and FIGS. 9-10 showing dual intercoolers for
the main compressor, a single intercooler for a secondary
compressor and a control system and valves for selecting different
charge-air paths for light-load operations, and depicting (one in
phantom lines) two alternative systems of inducting a low pressure
primary air charge.
[0035] FIG. 16 shows suggested valve positions for supplying
manifolds 13 and 14 with an air charge optimum for medium-load
operation for the engines of FIGS. 5-7 and FIGS. 9-10. For
medium-load operation the shutter valve 5 of compressor 2 would be
closed and the air bypass valve 6 would be open to pass the air
charge uncooled without compression to the intake of compressor 1
where closed shutter valve 3 and closed air bypass valve 4 directs
the air charge now compressed by compressor 1 past the intercoolers
to manifolds 13 and 14 with the air compressed and heated by
compressor 1, for medium-load operation.
[0036] FIG. 17 shows a suggested scenario for providing the engines
of FIGS. 5-7 and FIGS. 9-10 with a high density air charge for
heavy duty, high power output operation. FIG. 17 shows all shutter
valves 5 and 3 and all air bypass valves 6 and 4 closed completely
so that the primary stage of compression is operative and a second
stage of compression is operative and the entire air charge, with
the exception of any going through conduit 32 to intake valve 16-B,
is being passed through the intercoolers 10, 11 and 12 to produce a
very high density air charge to manifolds 13 and 14 and to the
engines power cylinders for heavy-load operation.
[0037] FIG. 18 shows a schematic drawing representing any of the
engines of FIG. 3-FIG. 11, depicting an alternative type of
auxiliary compressor 2' and a system of providing a means for
disabling or cutting out the auxiliary compressor when high charge
pressure and density is not needed. For relieving compressor 2' of
work, shutter valve 5 is closed and air bypass valve is opened so
that air pumped through compressor 2' can re-circulate through
compressor 2' without requiring compression work.
[0038] FIG. 19 is a schematic drawing representing the engines
shown in FIGS. 5-7 and FIGS. 9-10 and having two compressors, and
one intercooler for one stage of compression, dual intercoolers for
a second stage of compression, dual manifolds, four valves and an
engine control module (ECM) and illustrating means of controlling
charge-air density, pressure and temperature by varying directions
and amounts of air flow through the various electronic or vacuum
operated valves and their conduits.
[0039] FIG. 20 is a schematic drawing showing optional electric
motor drive of the air compressors of the engines of FIG. 1 through
FIG. 11.
[0040] FIG. 21 is a schematic transverse sectional view of a
pre-combustion chamber, a combustion chamber and associated fuel
inlet ducts and valving suggested for gaseous or liquid fuel
operation for the engines of this invention or for any other
internal combustion engine.
[0041] FIG. 22 is a part sectional view through one cylinder of an
engine showing an alternate construction whereby there is supplied
two firing strokes each revolution of the shaft for a 2-stroke
engine and one firing stroke each revolution of the shaft for a
4-stroke engine, having a beam which pivots on its lower extremity,
a connecting rod which is joined mid-point of the beam and is
fitted to the crankshaft of the engine, and whereby a means is
provided for varying the compression ratio of the engine at
will.
[0042] FIG. 23 is a part sectional view through one cylinder of an
engine showing an alternate construction whereby there is supplied
two firing strokes each crankshaft revolution for a 2-stroke engine
and one firing stroke each revolution of the shaft for a 4-stroke
engine, and whereby the beam connecting the connecting rod and the
piston pivots at a point between the piston and the piston
connecting rod, which connecting rod is attached to the crankshaft
of the engine, and an alternate preferred means of power take-off
from the piston by a conventional piston rod, cross-head and
connecting rod arrangement.
[0043] FIG. 24 is a part sectional view through one cylinder of an
engine showing a means of providing extra burn-time each firing
stroke in a 2-stroke or 4-stroke engine.
[0044] FIG. 25 is a perspective view of the cylinder block and head
of a six cylinder internal combustion engine operating in a
2-stroke cycle and representing a yet another embodiment of the
apparatus of the present invention from which still another method
of operation of can be performed and will be described. Among its
other components, this embodiment is seen as having scavenging
ports in the bottom of the piston sleeves and having a primary and
an ancillary compressor, a cooling system, valves and conduits to
control the pressure, density and temperature of the charge-air,
and valves and conduits to supply scavenging air to the
cylinders.
[0045] FIG. 26 is a schematic drawing of an engine similar to the
engine of FIG. 25 showing one intercooler for one optional stage of
compression, dual intercoolers for a primary compression stage and
showing a control system (including engine control module (ECM) and
valving) for controlling charge-air density, weight, temperature
and pressure by controlling directions and amounts of air flow
through the various valves, conduits and an optional throttle
valve, and showing two optional routes for supplying scavenging air
to the scavenging ports in the bottom of the cylinders, and
alternative routes for the exhausted gases to exit the engine.
[0046] FIG. 27 through FIG. 30 are schematic drawings of the engine
of FIG. 25 and FIG. 26 showing four alternate methods suggested for
efficient scavenging of the engines, FIG. 27 and FIG. 28 also show
a schematic drawing for an engine control module (ECM) and valving
to control charge-air and scavenging air at a pressure, density and
temperature deemed appropriate for each.
[0047] FIG. 31 is a schematic drawing showing suggested optional
electric motor drive for the engine's air compressors.
[0048] FIG. 32 is a schematic drawing of the 2-stroke engine of
FIG. 25 and FIG. 26, having only one compressor for supplying both
charge-air and scavenging air, and showing a control system and
means of controlling charge and scavenging air at a pressure,
density and temperature deemed appropriate for each, and showing
means of channeling the air through different paths for the same
purpose;
[0049] FIG. 33 is a schematic transverse sectional view through a
six cylinder engine having two compressor cylinders, four power
cylinders, one supercharger, five regulatory valves, and showing an
engine control module (ECM) for controlling charge temperatures,
density and weight, and adopted for storage of compressed air
compressed by regenerative braking, or for storage of bleed-air
produced in some industrial processes, in any of the engines of
this invention.
[0050] FIG. 34 is a schematic drawing representing any of the
engines of the present invention and showing an alternate
embodiment which includes a separate, electric-powered air
compressor and, alternatively, an entrance conduit leading from a
supply of waste or "bleed" compressed air for supplying charge-air
to the engine (or to a plurality of engines), whereby the need for
engine-powered compressors is eliminated.
[0051] FIG. 35 is a schematic drawing representing any of the
engines of the present invention depicted in an alternate
embodiment which is configured to operate as a constant load and
constant speed engine. This constant load and constant speed engine
embodiment of the present invention is shown as including both a
primary and an ancillary compressor with optional intercoolers for
providing two stages of pre-compressed charge-air, either
optionally intercooled or adiabatically compressed.
[0052] FIG. 36 is a schematic drawing representing any of the
engines of the present invention, and depicting a constant load and
constant speed engine in accordance with an alternate embodiment of
the present invention in which there is provided a single
compressor with optional intercoolers for providing a single stage
of pre-compressed charge-air, either optionally intercooled or
adiabatically compressed.
DETAILED DESCRIPTION OF THE DRAWINGS
[0053] With reference now in greater detail to the drawings, a
plurality of alternate, preferred embodiments of the apparatus of
the Improved Internal Combustion Engine 100 of the present
invention are depicted. Like components will be represented by like
numerals throughout the several views; and, in some but not all
circumstances, as the writer might deem necessary (due to the large
number of embodiments), similar but alternate components will be
represented by superscripted numerals (e.g., 100.sup.1). When there
are a plurality of similar components, the plurality is often times
referenced herein (e.g., six cylinders 7a-7f), even though fewer
than all components are visible in the drawing. Also, components
which are common among multiple cylinders are sometimes written
with reference solely to the common numeral, for ease of
drafting--e.g. piston 22a-22f=>piston 22. In an effort to
facilitate the understanding of the plurality of embodiments, (but
not to limit the disclosure) some, but not all, sections of this
Detailed Description are sub-titled to reference the system or
sub-system detailed in the subject section.
[0054] The invented system of the present invention is, perhaps,
best presented by reference to the method(s) of managing combustion
charge densities, temperatures, pressures and turbulence; and the
following description attempts to describe the preferred methods of
the present invention by association with and in conjunction with
apparatuses configured for and operated in accordance with the
alternate, preferred methods.
[0055] Some, but not necessarily all, of the system components that
are common to two or more of the herein depicted embodiments
include a crankshaft 20, to which are mounted connecting rods
19a-19f, to each of which is mounted a piston 22a-22f; each piston
traveling within a power cylinder 7a-7f; air being introduced into
the cylinders through inlet ports controlled by intake valves 16,
and air being exhausted from the cylinders through exhaust ports
controlled by exhaust valves 17. The interaction, modification and
operation of these and such other components as are deemed
necessary to an understanding of the various embodiments of the
present invention are expressed below.
The engine 100.sup.1 of FIG. 1
[0056] Referring now to FIG. 1, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.1 in which all of
the cylinders 7a-7f (only one of which is shown in a sectional
view) and associated pistons 22a-22f operate in a 4-stroke cycle
and all power cylinders are used for producing power to a common
crankshaft 20 via connecting rods 19a-19f, respectively. An
ancillary compressor 2 (herein depicted as a Lysholm rotary
compressor) selectably supplies air which has been compressed, or
allows delivery of air therethrough at atmospheric pressure, to
manifolds 13 and 14 and to cylinders 7a-7f, which cylinders operate
in a 4-stroke cycle. Valves 3, 5 and 6 and intercoolers 10, 11 and
12 are used, in the preferred embodiments, to control air charge
density, weight, temperature and pressure. The intake valves
16a-16f, 16a'-16f' are timed to control the compression ratio of
the engine 100.sup.1. The combustion chambers are sized to
establish the expansion ratio of the engine.
[0057] The engines 100.sup.1-100.sup.5, 100.sup.7 of FIG. 1, FIG.
2, FIG. 3, FIG. 4, FIG. 5, and FIG. 7, respectively, have camshafts
21 fitted with cams and are arranged to be driven at one-half the
speed of the crankshaft in order to supply one power stroke for
every two revolutions of the crankshaft, for each power piston. The
rotary compressors 2 of FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 4-B,
FIG. 5, FIG. 7 and FIG. 33 can be driven by a ribbed V-belt and
would have a step-up gear between the V pulley and the compressor
drive shaft, the rotary compressors could also be fitted with a
variable-speed step-up gear as in some aircraft engines. The
reciprocating compressor 1 of FIG. 3 is shown as having
double-acting cylinders linked to the crankshaft 20 by a connecting
rod 19g; and the crankshaft 20 to which it is linked by connecting
rod 19g would supply two working strokes for each revolution of the
crankshaft 20. In one alternate approach, the reciprocating
compressor 1 is driven by the connecting rod 19g being connected to
a short crankshaft above the main crankshaft 20 to which the
ancillary crankshaft (not shown) would be geared by a step-up gear
in order to provide more than two working strokes per revolution of
the main crankshaft 20. Alternatively, the compressor system can
have multiple stages of compression for either rotary or
reciprocating compressors. Whereas, the ancillary compressor 1 and
second ancillary compressor 2 of the various embodiments are
depicted throughout as a reciprocating compressor or a rotary
compressor, it is noted that the invention is not limited by the
type of compressor utilized for each; and the depicted compressors
may be interchanged, or may be the same, or may be other types of
compressors performing the functions described herein.
[0058] The engine 100.sup.1 shown in FIG. 1 is characterized by a
more extensive expansion process, a low compression ratio and the
capability of producing a combustion charge varying in weight from
lighter-than-normal to heavier-than-normal, and capable of
providing, selectively, a mean effective cylinder pressure higher
than can the conventional arrangement of normal engines but capable
of having a lower maximum cylinder pressure in comparison to
conventional engines. An engine control module (ECM) (not shown in
FIG. 1) and variable valves 3, 5 and 6 on conduits, as shown,
provide a system for controlling the charge density, pressure,
temperature, and the mean and peak pressure within the cylinder
which allows greater fuel economy, production of greater torque and
power at low RPM, with low polluting emissions for both spark and
compression-ignited engines. In alternate embodiments, a variable
valve timing system can be used and, with a control system such as
an ECM, can control the time of opening and the time of closing of
the intake valves 16 and 16' to further provide an improved
management of conditions in the combustion chambers of cylinders
7a-7f of the engine 100a to allow for a flatter torque curve and
higher power, when needed, and with low levels of both fuel
consumption and polluting emissions.
Brief Description of Operation of the Engine 100.sup.1 Shown in
FIG. 1
[0059] The engine 100.sup.1 of this invention shown in FIG. 1 is a
high efficiency engine that attains both high power and torque with
low fuel consumption and low polluting emissions. The new working
cycle is an external compression type combustion cycle. In this
cycle, part of the intake air (all of which is compressed in the
power cylinders in conventional engines) is, selectively,
compressed by at least one ancillary compressor 2. The temperature
rise during compression can be suppressed by use of air coolers 10,
11, 12 which cool the intake air, and by a shorter compression
stroke.
[0060] One suggested, preferred method of operation of the
new-cycle engine 100.sup.1 is thus: [0061] 1. Depending upon the
power requirements of the engine (e.g., differing load
requirements), either intake air at atmospheric pressure or intake
air that has been compressed by at least one ancillary compressor 2
and has had its temperature and pressure controlled by bypass
systems and charge-air coolers, is drawn into the power cylinder 7
by the intake stroke of piston 22. [0062] 2. (a) After the intake
stroke is complete, the intake valve 16 (which can be single or
multiple, 16, 16') is left open for a period of time after the
piston 22 has passed bottom dead center, which pumps part of the
fresh air charge back into the intake manifold 13, 14. The intake
valve 16, 16' is then closed at a point which action seals the
cylinder 7, thus establishing the compression ratio of the engine.
[0063] (b) Alternatively, the intake valve 16, 16' is closed early,
during the intake stroke, before the piston 22 has reached bottom
dead center. The trapped air charge is then expanded to the full
volume of the cylinder 7 and compression of the charge starts when
the piston 22 returns to the point in the compression stroke at
which the intake valve 16, 16' closed. [0064] 3. (a) During the
compression stroke of piston 22, at the point the intake valve 16
closed, either in 2(a) or 2(b) operation, compression begins,
producing a small compression ratio. This makes it possible to
restrain the temperature rise during the compression stroke. [0065]
(b) During light-load operation, such as in vehicle cruising or
light-load power generation, the shutter valve 5 is closed and the
air bypass valve (ABV) 6 on the compressor is, preferably opened so
that the intake air is returned to the intake conduit 8 of the
compressor 2 without being compressed. Shutter valve 3 can then
direct the air charge around or through intercoolers 11 and 12.
During this time, the engine pistons 22a-22f are drawing in
naturally aspirated air through the compressor 2. This reduces
compressor drive work and improves fuel economy. [0066] (c) When
more power is required, the charge density and pressure can be
increased by closing air bypass valve (ABV) 6 causing compressor 2
to raise the air pressure and, alternatively, this can be
accomplished by either cutting in a second stage of compression by
compressor 1, as shown in FIG. 2, or by increasing the speed of
compressor 2. At the same time, control valves 5 and 3 preferably,
direct some or all of the air charge through one or more of
intercoolers 10, 11, and 12 in order to increase charge-air
density. [0067] 4. Compression continues, fuel is added, if not
already present, the charge is ignited and combustion produces a
large expansion of the gases against the piston 22 producing great
energy in either mode 3(a), (b) or (c). This energy produces a high
mean effective cylinder pressure and is converted into high torque
and power, especially in mode (c).
Detailed Description of Operation of the Engine 100.sup.1 of FIG.
1
[0068] During the intake (1st) stroke of the piston 22 air flows
through air conduits 15 from a manifold of air 13 or 14, which air
(depending on power requirements) is either at atmospheric pressure
or has been compressed to a higher pressure by compressor 2,
through the intake valve 16 into the cylinder 7. During the intake
stroke of piston 22 the intake valve 16 closes early (at point x).
From this point, the cylinder 7 contents are expanded to the
maximum volume of the cylinder. Then, during the compression (2nd)
stroke, no compression takes place until the piston 22 has returned
to the point x where the intake valve 16 was closed during the
intake stroke. (At point x, the remaining displaced volume of the
cylinder is divided by the volume of the combustion chamber, to
establish the compression ratio of the engine.) Alternatively,
during the intake (1st) stroke of piston 22, the intake valve 16 is
held open through the intake stroke and past bottom dead center
piston position, and through part of the compression (2nd) stroke
for a significant distance, 10% or, to perhaps 50% or more of the
compression stroke, thus pumping some of the charge-air back into
intake manifold 13 or 14, and the intake valve 16 then closes to
establish a low compression ratio in the cylinders of the engine.
At the time of closure of intake valve 16, the density, temperature
and pressure of the cylinder will be at approximate parity with the
manifold 13 or 14 contents.
[0069] During light-load operation, such as in vehicle cruising or
light-load power generation, the shutter valves 5 and 3 are closed
and the air bypass valve (ABV) 6 on the compressor is, preferably,
opened so that the intake air is returned to the intake conduit 8
of the compressor 2 without being compressed. During this time the
engine pistons 22a-22f are drawing in naturally aspirated air
through the compressor 2. This reduces compressor drive work and
improves fuel economy.
[0070] When medium torque and power is needed, such as highway
driving or medium electric power generation, preferably the shutter
valve 5 to compressor 2 is closed and the air bypass valve (ABV) 6
is closed also. This causes the atmospheric pressure intake air to
cease re-circulating through the compressor 2 and the compressor 2
begins to compress the charge-air to a higher-than-atmospheric
pressure, while the closed shutter valves 5 and 3 direct the
charge-air through conduits 104, 110, 111, and 121/122 bypassing
the air coolers 10, 11 and 12, with the charge-air going directly
to the manifolds 13 and 14 to power cylinders 7a-7f where the
denser, but hot, charge increases the mean effective cylinder
pressure of the engine to create greater torque.
[0071] When more power is needed, such as when rapid acceleration
is needed or for heavy-load electric power generation, preferably
the air bypass valve (ABV) 6 is closed and the shutter valves 3 or
5 or both are opened. This causes the compressor 2 to compress all
of the air charge. Shutter valves 3 or 5 or both then supply
(depending on the respective opened/closed conditions of valves 3
and 5), the conditioned air charge through conduits 105 or 104, to
conduit 110, and then through conduits 111 or 112 to the manifolds,
13, 14 and to the cylinders 7a-7f via one, two, or all three of the
charge coolers 10, 11 and 12. The very dense cooled air charge when
mixed with fuel and ignited and expanded beyond the compression
ratio of the engine produces great torque and power.
[0072] When greater power is needed the charge-air density and
weight can be increased by increasing the speed of the compressor 2
or by cutting in a second compressor as in FIG. 2, for a second
stage of pre-compression. The latter can be done by the engine
control module 27 signaling air bypass valve (ABV) 6, FIG. 2, to
close to prevent re-circulation of part of the intake air into
conduit 103 which negates, selectively, any second compression
stage during light-load operation. At the time air density and
pressure is increased, shutter valves 3 and 5 can direct part of
all of the air charge through intercoolers 10, 11 and 12 in order
to condense the charge and lessen the increase in the charge
temperature and pressure, both accomplished by the cooling of the
charge. This increases the mean effective cylinder pressure during
combustion for high torque and power.
[0073] The heavier the weight of the air charge and the denser the
charge, the earlier in the intake stroke (or the later in the
compression stroke) the intake valve can be closed to establish a
low compression ratio and retain power, and the less heat and
pressure is developed during compression in the cylinder. In this
4-stroke engine the intake charge can be boosted in pressure by as
much as 4-5 atmospheres and if the compression ratio is low enough,
say 4:1 to 8:1 (higher for diesel fuel), even spark-ignited there
would be no problem with detonation. The expansion ratio should
still be large, 14:1 would be a preferred expansion ratio for spark
ignition, perhaps 19:1 for diesel operation.
[0074] The compression ratio is established by the displaced volume
of the cylinder 7 remaining after point x has been reached in the
compression stroke (and intake valve 16 is closed) being divided by
the volume of the combustion chamber. The expansion ratio in all
cases is greater than the compression ratio. The expansion ratio is
established by dividing the total displaced volume of the cylinder
by the volume of the combustion chamber.
[0075] Fuel can be carbureted, or it can be injected in a
throttle-body 56 (seen in FIG. 16), or the fuel can be injected
into the inlet stream of air, injected into a pre-combustion
chamber (FIG. 21) or, injected through the intake valve 16, or it
may be injected directly into the combustion chamber. If injected,
it should be at or after the piston 22 has reached point x and the
intake valve is closed. The fuel can also be injected later,
similar to diesel operation, and can be injected at the usual point
for diesel oil injection, perhaps into a pre-combustion chamber or
directly into the combustion chamber or directly onto a glow plug.
Some fuel can be injected after top dead center even continuously
during the first part of the expansion stroke for a mostly constant
pressure combustion process.
[0076] Ignition can be by compression (which may be assisted by a
glow plug), or by electric spark. Spark ignition can take place
before top dead center, as normally done, at top dead center or
after top dead center.
[0077] At an opportune time the air-fuel charge is ignited and the
gases expand against the piston for the power (3rd) stroke. Near
bottom dead center at the opportune time exhaust valve(s) 17 open
and piston 22 rises in the scavenging (4th) stroke, efficiently
scavenging the cylinder by positive displacement, after which
exhaust valve(s) 17 closes.
[0078] This completes one cycle of the 4-stroke engine.
The Engine 100.sup.2 of FIG. 2
[0079] Referring now to FIG. 2, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.2 in which all of
the cylinders 7a-7f (only two 7a, 7f of which are shown in a
schematic drawing) and associated pistons 22a-22f operate in a
4-stroke cycle and all power cylinders are used for producing power
to a common crankshaft 20 via connecting rods 19a-19f,
respectively. An ancillary compressor 2 (herein depicted as a
rotary compressor) supplies air which has been compressed, or
allows delivery of air therethrough at atmospheric pressure, to
manifolds 13 and 14 and to cylinders 7a-7f which cylinders operate
in a 4-stroke cycle. A second ancillary compressor 1 is used,
selectively, to boost the air pressure to compressor 2. Valves 3,
4, 5 and 6 and intercoolers 10, 11 and 12 are used, in the
preferred embodiments, to control air charge density, weight,
temperature and pressure. The intake valves 16a-16f are timed to
control the compression ratio of the engine 100.sup.2. The
combustion chambers are sized to establish the expansion ratio of
the engine.
[0080] The engine 100.sup.2 shown in FIG. 2 is characterized by a
more extensive expansion process, a low compression ratio and the
capability of producing a combustion charge varying in weight from
lighter-than-normal to heavier-than-normal, and capable of
selectively providing a mean effective cylinder pressure higher
than can the conventional arrangement of normal engines but having
similar or lower maximum cylinder pressure in comparison to
conventional engines. An engine control module (ECM) 27 and
variable valves 3, 4, 5 and 6 on conduits, as shown, provide a
system for controlling the charge density, pressure, temperature,
and the mean and peak pressure within the cylinder which allows
greater fuel economy, production of greater torque and power at low
RPM, with low polluting emissions for both spark and
compression-ignited engines. In alternate embodiments, a variable
valve timing system can be used and, with a control system such as
an engine control module (ECM) 27, can control the time of opening,
and the time of closing of the intake valves 16 to further provide
an improved management of conditions in the combustion chambers of
cylinders 7a-7f of the engine 100.sup.2 to allow for a flatter
torque curve and higher power, and with low levels of both fuel
consumption and polluting emissions.
Brief Description of Operation of the Engine 100.sup.2 of FIG.
2
[0081] The engine 100.sup.2 of this invention shown in FIG. 2 is a
high efficiency engine that attains both high power and torque with
low fuel consumption and low polluting emissions. The new working
cycle is an external compression type combustion cycle. In this
cycle, part of the intake air (all of which is compressed in the
power cylinders in conventional engines) is compressed,
selectively, by at least one ancillary compressor 1, 2. The
temperature rise during compression can be suppressed by use of air
coolers 10, 11, 12, which cool the intake air, and by a shorter
compression stroke.
[0082] One suggested, preferred method of operation of the
new-cycle engine 100.sup.2 is thus: [0083] 1. Depending upon the
power requirements of the engine (e.g., differing load
requirements), either intake air at atmospheric pressure or intake
air that has been compressed by at least one ancillary compressor
and has had its temperature and pressure adjusted by bypass systems
and charge-air coolers, is drawn into the power cylinder 7 by the
intake stroke of piston 22. [0084] 2. (a) After the intake stroke
is complete, the intake valve 16 (which can be single or multiple)
is left open for a period of time after the piston 22 has passed
bottom dead center which pumps part of the fresh air charge back
into the intake manifold 13,14. The intake valve 16 is then closed
at a point which action seals cylinder 7, thus establishing the
compression ratio of the engine. [0085] (b) Alternatively, the
intake valve 16 is closed early, during the intake stroke, before
the piston 22 has reached bottom dead center. The trapped air
charge is then expanded to the full volume of the cylinder 7 and
compression of the charge starts when the piston 22 reaches the
point in the compression stroke at which the intake valve 16
closed. [0086] 3. (a) During the compression stroke of piston 22,
at the point the intake valve 16 closed, either in 2(a) or 2(b)
operation, compression begins, producing a small compression ratio.
This makes it possible to lessen the temperature rise during the
compression stroke. [0087] (b) During light-load operation, such as
in vehicle cruising or light-load power generation, the shutter
valves 3 and 5 are closed and the air bypass valves (ABV) 4 and 6
to both compressors 1 and 2 are, preferably, opened so that the
intake air is returned to the intake conduits 110 and 103 of the
compressors 2 and 1 without being compressed. During this time, the
engine pistons 22a-22f are drawing in naturally aspirated air past
the compressor(s). This reduces compressor drive work and further
improves fuel economy. [0088] (c) When greater power is required,
the charge density and pressure can be increased by closing air
bypass valve (ABV) 4 causing compressor 2 to raise the charge-air
pressure and, in addition, by either cutting in the second stage of
compression by compressor 1 in the same manner, that of closing air
bypass valve ABV 6, or by increasing the speed of compressor 2 or
of both compressors. At the same time, shutter valves 3 and 5 would
be opened to direct some or all of the air charge through
intercoolers 10, 11 and 12 in order to increase charge-air density.
[0089] 4. Compression continues, fuel is added if not already
present, the charge is ignited and combustion produces a large
expansion of the gases against piston 22 producing great energy in
either mode 3(a), (b) or (c). This energy produces a high mean
effective cylinder pressure and is converted into high torque and
power, especially in mode (c). Detailed Description of Operation of
the engine 100.sup.2 of FIG. 2
[0090] During the intake (1st) stroke of the piston 22 air flows
through air conduits 15 from the manifold 13 or 14 of air which air
(depending on power requirements) is either at atmospheric pressure
or has been compressed to a higher pressure by compressor 2 and/or
compressor 1, through the intake valve 16 into the cylinder 7.
During the intake stroke of piston 22 the intake valve 16 closes at
point x sealing cylinder 7. From this point the air charge is
expanded to the maximum volume of the cylinder. Then during the
compression (2nd) stroke, no compression takes place until the
piston 22 has returned to the point x where the intake valve 16 was
closed during the intake stroke. (At point x, the remaining
displaced volume of the cylinder is divided by the volume of the
combustion chamber, to establish the compression ratio of the
engine.) Alternatively, during the intake (1st) stroke of piston
22, the intake valve 16 is held open through the intake stroke and
passed bottom dead center, and through part of the compression
(2nd) stroke for a significant distance, 10% or, to perhaps 50% or
more of the compression stroke, thus pumping some of the charge-air
back into intake manifold 13 or 14, and the intake valve 16 then
closes, sealing cylinder 7, to establish a low compression ratio in
the cylinders of the engine. At the time of closure of intake valve
16, the density, temperature and pressure of the cylinder 7
contents will be approximately the same as that of the air charge
in the intake manifolds 13 and 14.
[0091] During light-load operation, such as in vehicle cruising or
light-load power generation, the shutter valves 3 and 5 are closed
and the air bypass valves (ABV) 4 and 6 to both compressors 1 and 2
are, preferably opened so that the intake air is returned to the
intake conduits 110 and 103 of the compressors 2 and 1 without
being compressed. During this time the engine pistons 22a-22f are
drawing in naturally aspirated air past the compressor(s). This
reduces compressor drive work and further improves fuel
economy.
[0092] When medium torque and power is needed, such as highway
driving or medium electric power generation, preferably the shutter
valves 3 and 5 are closed and the air bypass valves (ABV) 4 and 6
are closed. This causes the atmospheric pressure intake air to
cease re-circulating through the compressor 2 and 1 and both
compressors begin to compress the charge-air to a
higher-than-atmospheric pressure, while the closed shutter valves 3
and 5 direct the charge-air through conduits 104, 110, 111, and
121/122 bypassing the air coolers 10, 11 and 12, in FIG. 2, with
the charge-air going directly to the manifold 13 and 14 and to
power cylinders 7a-7f where the denser, but hot, charge increases
the mean effective cylinder pressure of the engine to create
greater torque and power.
[0093] When more power is needed, such as when rapid acceleration
is needed or for heavy-load electric power generation, preferably
the air bypass valve (ABV) 4 is closed and the shutter valve 3 is
opened. This causes the compressor 2 to compress all of the air
charge and shutter valve 3 directs the air charge through conduits
112 and 113 and the compressed charge-air is supplied to the
manifolds 13 and 14 and to the cylinders 7a-7f via the charge
coolers 11 and 12. For even greater power the shutter valve 5 is
opened and the air bypass valve 6 is closed and compressor 1 begins
a second stage of compression, and all of the air charge is now
directed through intercoolers 10, 11 and 12 for high charge
density. The very dense cooled air charge when mixed with fuel and
ignited and expanded beyond the compression ratio of the engine
produces great torque and power.
[0094] The heavier the weight of the air charge and the denser the
charge, the earlier (or later) the intake valve can be closed to
establish a low compression ratio and retain power, and the less
heat and pressure is developed during compression in the cylinder.
In this 4-stroke engine the intake charge can be boosted in
pressure by as much as 4-5 atmospheres and if the engine's
compression ratio is low enough, say 4:1 to 8:1 (higher for diesel
fuel), even spark-ignited there would be no problem with
detonation. The expansion ratio would still be very large, 14:1
would be a preferable expansion ratio for spark ignition, perhaps
19:1 for diesel operation.
[0095] The compression ratio is established by the displaced volume
of the cylinder 7 remaining after point x has been reached in the
compression stroke (and intake valve 16 is closed) being divided by
the volume of the combustion chamber. The expansion ratio in all
cases is greater than the compression ratio. The expansion ratio is
established by dividing the total displaced volume of the cylinder
by the volume of the combustion chamber.
[0096] Fuel can be carbureted, or it can be injected in a
throttle-body 56 (seen in FIG. 16), or the fuel can be injected
into the inlet stream of air, injected into a pre-combustion
chamber as in FIG. 21 or, injected through the intake valve 16, or
it may be injected directly into the combustion chamber. If
injected, it should be at or after the piston 22 has reached point
x and the intake valve is closed. The fuel can also be injected
later and in the case of diesel operation can be injected at the
usual point for diesel oil injection, perhaps into a pre-combustion
chamber or directly into the combustion chamber or directly onto a
glow plug.
[0097] At an opportune time the air-fuel charge is ignited and the
gases expand against the piston for the power (3rd) stroke. Near
bottom dead center at the opportune time exhaust valve(s) 17 open
and piston 22 rises in the scavenging (4th) stroke, efficiently
scavenging the cylinder by positive displacement, after which the
exhaust valve(s) closes.
[0098] This completes one cycle of the 4-stroke engine.
The Engine 100.sup.3 of FIG. 3
[0099] Referring now to FIG. 3, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.3 in which all of
the cylinders 7a-7f (only one of which is shown in a sectional
view) and associated pistons 22a-22f operate in a 4-stroke cycle
and all power cylinders are used for producing power to a common
crankshaft 20 via connecting rods 19a-19f, respectively. An
ancillary reciprocating compressor 1 and an ancillary rotary
compressor 2 supply pressurized charge air which has been
compressed, or allow deliver of air therethrough at atmospheric
pressure, to manifolds 13, 14 and to cylinders 7a-7f, which
cylinders operate in a 4-stroke cycle. Valves 3, 4, 5 and 6 and
intercoolers 10, 11 and 12 are used, in the preferred embodiments,
to control air charge density, weight, temperature and pressure.
The intake valves 16 are timed to control the compression ratio of
the engine 100.sup.3. The combustion chambers are sized to
establish the expansion ratio of the engine.
[0100] The engine 100.sup.3 shown in FIG. 3 is characterized by a
more extensive expansion process, a low compression ratio and the
capability of producing a combustion charge varying in weight from
lighter-than-normal to heavier-than-normal, and capable of
selectively providing a mean effective cylinder pressure higher
than can the conventional arrangement of normal engines but having
similar or lower maximum cylinder pressure in comparison to
conventional engines. An engine control module (ECM) 27 and
variable valves 3, 4, 5 and 6 on conduits, as shown, provide a
system for controlling the charge density, pressure, temperature,
and the mean and peak pressure within the power cylinder 7 which
allows greater fuel economy, torque and power at low RPM, with low
polluting emissions for both spark and compression-ignited engines.
In alternate embodiments, a variable valve timing system can be
used and, with a control system such as an engine control module
(ECM) 27, can control the time of opening and the time of closing
of the intake valves 16 to further provide an improved management
of conditions in the combustion chambers of cylinders 7a-7f of the
engine 100.sup.3 to allow for a flatter torque curve and high power
and with low levels of both fuel consumption and polluting
emissions.
Brief Description of Operation of the Engine 100.sup.3 of FIG.
3
[0101] The engine 100.sup.3 of this invention shown in FIG. 3 is a
high efficiency 30 engine that attains both high power and torque
with low fuel consumption and low polluting emissions. The new
working cycle is an external compression type combustion cycle. In
this cycle part of the intake air (all of which is compressed in
the power cylinders in conventional engines) is selectively
compressed by at least one ancillary compressor 1, 2. The
temperature rise during compression can be suppressed by use of air
coolers 10, 11, 12, which cool the intake air, and by a shorter
compression stroke.
[0102] One suggested, preferred method of operation of the
new-cycle engine 100.sup.3 is thus: [0103] 1. Depending upon the
power requirements of the engine (e.g., differing load
requirements), either intake air at atmospheric pressure or intake
air that has been compressed by at least one ancillary compressor
and has had its temperature and pressure adjusted by bypass systems
and charge-air coolers, is drawn into the power cylinder 7 by the
intake stroke of piston 22. [0104] 2. (a) After the intake stroke
is complete the intake valve 16 (which can be single or multiple,
16, 16') is left open for a period of time after the piston 22 has
passed bottom dead center which pumps part of the fresh air charge
back into the intake manifolds 13, 14. The intake valve 16 is then
closed at a point which seals cylinder 7, thus establishing the
compression ratio of the engine. [0105] (b) Alternatively, the
intake valve 16 is closed early, during the intake stroke, before
the piston 22 has reached bottom dead center. The trapped air
charge is then expanded to the full volume of the cylinder 7 and
compression of the charge starts when the piston 22 reaches the
point in the compression stroke at which the intake valve 16
closed. [0106] 3. (a) During the compression stroke of piston 22,
at the point the intake valve 16 closed, either in 2(a) or 2(b)
operation, compression begins, producing a small compression ratio.
This makes it possible to lessen the temperature rise during the
compression stroke. [0107] (b) During light-load operation, such as
in vehicle cruising or light-load power generation, the shutter
valves 3 and 5 are closed and the air bypass valves (ABV) 4 and 6
on both compressors 1 and 2 are, preferably, opened so that the
intake air is returned to the intake conduits 110 and 8 of the
compressors 1 and 2 without being compressed. During this time the
engine pistons 22a-22f are drawing in naturally aspirated air past
the compressor(s). This reduces compressor drive work and further
improves fuel economy. [0108] (c) When greater power is required,
the charge density and pressure can be increased by closing air
bypass valve (ABV) 4 causing compressor 1 to raise the charge-air
pressure and, in addition, by either cutting in the second stage of
compression by compressor 2, if needed, in the same manner, that of
closing ABV valve 6, or by increasing the speed of compressors 1 or
2, or both. At the same time, shutter valves 3 and 5 would direct
some or all of the air charge through intercoolers 10, 11, and 12
in order to increase charge-air density. [0109] 4. Compression
continues, fuel is added if not already present, the charge is
ignited and combustion produces a large expansion of the gases
against piston 22 producing great energy in either mode 3(a), (b)
or (c). This energy produces a high mean effective cylinder
pressure and is converted into high torque and power, especially in
mode (c).
Detailed Description of Operation of the Engine 100.sup.3 of FIG.
3
[0110] During the intake (1st) stroke of the piston 22 air flows
through air conduits 15 from the manifold 13 or 14 of air which air
(depending on power requirements) is either at atmospheric pressure
or has been compressed to a higher pressure by compressor 1 or 2
through the intake valve 16 into the cylinder 7. During the intake
stroke of piston 22 the intake valve 16 closes (at point x). From
this point the cylinder contents are expanded to the maximum volume
of the cylinder. Then during the compression (2nd) stroke, no
compression takes place until the piston 22 has returned to the
point x where the intake valve 16 was closed, sealing the cylinder
7, during the intake stroke. (At point x, the remaining displaced
volume of the cylinder is divided by the volume of the combustion
chamber, to establish the compression ratio of the engine.)
Alternatively, during the intake (1st) stroke of piston 22, the
intake valve 16 can be held open through the intake stroke passed
bottom dead center, and through part of the compression (2nd)
stroke for a significant distance, 10% to perhaps 50% or more of
the compression stroke pumping some of the charge-air back into
intake manifold, and the intake valve 16, 16' then closes to
establish a low compression ratio in the cylinders of the
engine.
[0111] During light-load operation, such as in vehicle cruising or
light-load power generation, the shutter valves 3 and 5 are closed
and the air bypass valves (ABV) 4 and 6 on both compressors 1 and 2
are, preferably, opened so that the intake air is returned to the
intake conduits 110 and 8 of the compressors 1 and 2 without being
compressed. During this time the engine pistons 22a-22f are drawing
in naturally aspirated air past the compressor(s). This reduces
compressor drive work and further improves fuel economy.
[0112] When medium torque and power is needed, such as highway
driving or medium electric power generation, preferably the shutter
valve 3 to compressor 1 is opened, the air bypass valve (ABV) 4 is
closed and ABV 6 remains open. This causes the atmospheric pressure
intake air to cease re-circulating through the compressor 1; and
the compressor 1, alone, begins to compress the charge-air to a
higher-than-atmospheric pressure, while the closed shutter valves 3
and 5 directs the charge-air through conduits 104, 110, 111, and
121/122 bypassing the air coolers 10, 11 and 12, in FIG. 3, with
the charge-air going directly to the manifolds 13 and 14 and to
power cylinders 7a-7f where the denser heated charge increases the
mean effective cylinder pressure of the engine to create greater
torque and power.
[0113] When more power is needed, such as when rapid acceleration
is needed or for heavy-load electric power generation, preferably
the air bypass valves (ABV) 4 and 6 are closed and the shutter
valves 3 and 5 are opened on both compressors. This causes the
compressors 1 and 2 to compress all of the air charge and shutter
valves 3 and 5 direct the air charge away from conduit 8 and
through the compressors 1 and 2, and the compressed charge-air is
then supplied through conduits 105, 106, 110, 112, 113, 114 and 115
to the manifolds 13 and 14 and to the cylinders 7a-7f via the
charge coolers 10, 11 and 12. The very dense cooled air charge when
mixed with fuel and ignited and expanded beyond the compression
ratio of the engine produces great torque and power.
[0114] The heavier the weight of the air charge and the denser the
charge, the earlier in the intake stroke (or the later in the
compression stroke) the intake valve can be closed to establish a
low compression ratio and retain power, and the less heat and
pressure is developed during compression in the cylinder. In this
4-stroke engine the intake charge can be boosted in pressure by as
much as 4-5 atmospheres and if the compression ratio is low enough,
say 4:1 to 8:1 (higher for diesel fuel), even spark-ignited there
would be no problem with detonation. The expansion ratio would
still be very large, 14:1 would be a preferred expansion ratio for
spark ignition, perhaps 19:1 for diesel operation.
[0115] The compression ratio is established by the displaced volume
of the cylinder 7 remaining after point x has been reached in the
compression stroke (and intake valve 16 is closed) being divided by
the volume of the combustion chamber. The expansion in all cases is
greater than the compression ratio. The expansion ratio is
established by dividing the total displaced volume of the cylinder
by the volume of the combustion chamber.
[0116] Fuel can be carbureted, or it can be injected in a
throttle-body, or the fuel can be injected into the inlet stream of
air, injected into a pre-combustion chamber, FIG. 21, or, injected
through the intake valve 16, or it may be injected directly into
the combustion chamber. If injected, it should be at or after the
piston 22 has reached point x and the intake valve is closed. The
fuel can also be injected later and in the case of diesel operation
can be injected at the usual point for diesel oil injection,
perhaps into a pre-combustion chamber or directly into the
combustion chamber or directly onto a glow plug.
[0117] At an opportune time the air-fuel charge is ignited and the
gases expand the piston 22 for the power (3rd) stroke. Near bottom
dead center at the opportune time exhaust valve(s) 17 open and
piston 22 rises in the scavenging (4th) stroke, efficiently
scavenging the cylinder by positive displacement, after which
exhaust valve(s) 17 closes.
[0118] This completes one cycle of the 4-stroke engine.
The Engine 100.sup.4 of FIG. 4
[0119] Referring now to FIG. 4, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.4 having two
atmospheric air intakes 8 and 9 and corresponding intake conduits
15-A, 15-B, in which all of the cylinders (only one (7) of which is
shown in a sectional view) 7a-7f and associated pistons 22a-22f
operate in a 4-stroke cycle and all power cylinders are used for
producing power to a common crankshaft 20 via connecting rods
19a-19f, respectively. A compressor 2, in this figure a Lysholm
type rotary compressor, is shown which, with air conduits as shown,
supplies pressurized air to one or more cylinder intake valves
16-A. An air inlet 8 and an ancillary air inlet 9 and inlet
conduits 15-A, 15-B selectably supply air charge at atmospheric
pressure or air which has been compressed to a higher pressure to
separate intake valves 16-A and 16-B opening to the same cylinder
7a-7f (for example, shown here opening to cylinder 7f).
Intercoolers 10, 11 and 12 and control valves 3, 5 and 6 are used,
in the preferred embodiments, to control the air charge density,
weight, temperature and pressure. The intake valves 16a-B-16f-B
which receive air through manifold 14-B and intake conduits 15a-B
to 15f-B, are timed to control the compression ratio of the engine
100.sup.4. The combustion chambers are sized to establish the
expansion ratio of the engine. Because of noticeable similarities
between the engine 100.sup.4 of FIG. 4 and that of FIG. 7 (where
the auxiliary air inlet 9 system has been shown in phantom, for
informational value), reference will be made as deemed helpful to
FIG. 7 for certain common components.
[0120] The engine 100.sup.4 shown in FIG. 4 is characterized by a
more extensive expansion process, a low compression ratio and
capable of producing a combustion charge varying in weight from
lighter-than-normal to heavier-than-normal and capable of
selectively providing a mean effective cylinder pressure higher
than can the conventional arrangement in normal engines with
similar or lower maximum cylinder pressure in comparison to
conventional engines. Engine control module (ECM) 27 (refer, for
example to FIG. 7) and variable valves 3, 5, and 6 on conduits, as
shown, provide a system for controlling the charge pressure,
density, temperature, and mean and peak pressure within the
cylinder which allows greater fuel economy, production of greater
power and torque at all RPM, with low polluting emissions for both
spark and compression ignited engines. In alternate embodiments, a
variable valve timing system with the ECM 27 can also control the
time of opening and closing of the intake valves 16-A and/or 16-B,
to further provide an improved management of conditions in the
combustion chambers to allow for a flatter torque curve, and higher
power, with low levels of both fuel consumption and polluting
emissions.
Brief Description of Operation of the Engine 100.sup.4 Shown in
FIG. 4
[0121] The new cycle engine 100.sup.4 of FIG. 4 is a high
efficiency engine that attains both high power and torque, with low
fuel consumption and low polluting emissions. The new cycle is an
external compression type combustion cycle. In this cycle, part of
the intake air (all of which is compressed in the power cylinders
in conventional engines) is selectively compressed by an ancillary
compressor 2. The temperature rise at the end of compression can be
suppressed by use of air coolers 10, 11, 12, which cool the intake
air, by the late injection of temperature-adjusted-air, and by a
shorter compression stroke.
[0122] During operation, a primary air charge is supplied to the
cylinder 7 through intake valve 16-B at atmospheric pressure or air
which has been increased by perhaps one-half to one atmosphere
through an ancillary air inlet 9 which can be carbureted. This
charge can be compressed, fuel added if not present, ignited at the
appropriate point near top dead center for the power
stroke--providing high fuel economy and low polluting
emissions.
[0123] When more power is desired, a secondary air charge
originating from air inlet 8 is, preferably, introduced into the
power cylinder 7 during the compression stroke by a second intake
valve 16-A which introduces a higher pressure air charge after the
first intake valve 16-B has closed in order to increase the charge
density when needed. After the secondary air charge has been
injected, intake valve 16-A quickly closes. The primary air charge
may be boosted to a higher pressure by cutting in a second
ancillary compressor, in series with compressor 2, (see for
example, compressor 1 in FIG. 7, where the primary compressor to be
used in the engine of FIG. 4 is the compressor 2--shown in FIG. 4
and FIG. 7, for example, as a Lysholm rotary type) between air
inlet 8 and manifold 13, 14, and can be intercooled. The
temperature, pressure, amount and point of injection of the
secondary charge, if added, is adjusted to produce the desired
results. An intake valve disabler (there are several on the market,
for example, Eaton Corp. and Cadillac), in preferred embodiments,
may be used to disable intake valve 16-A when light-load operation
does not require a high mean effective cylinder pressure.
Alternatively, the air bypass valve (ABV) 6 is opened to
re-circulate the charge-air back through the compressor 2 in order
to relieve the compressor of compression work during light-load
operation.
[0124] Alternatively, a one-way valve, one type of which is shown
as 26 in FIG. 6 can be utilized to provide a constant or a variable
"pressure ratio" in the cylinder 7, while improving swirl
turbulence. In this alternate method of operation the intake valve
16-A would close very late and valve 26 would close only when the
pressure in the cylinder 7 nearly equates or exceeds the pressure
in conduit 15-A. Thus, the pressure in conduit 15-A, controlled by
compressor speed, along with valves 3, 5 and 6 (and valve 4 in FIG.
7) would regulate the pressure, density, temperature and turbulence
of the combustion process. A spring-retracted disc type, metal or
ceramic, or any other type of automatic valve could replace valve
26.
[0125] Another alternate method of providing a low compression
ratio, with a large expansion ratio and reduced polluting emissions
is thus:
[0126] The air pressure supplied to intake runner-conduit 15-A is
produced at an extremely high level, and intake valve 16-A is, in
alternate embodiments, replaced by a fast-acting, more controllable
valve such as but not limited to a high speed solenoid valve (not
shown), which valve is, preferably, either mechanically,
electrically or vacuum operated under the control of an engine
control module (ECM). In such an embodiment, a smaller, denser,
temperature-adjusted, high-pressure charge, with or without
accompanying fuel, can, selectively, be injected, tangentially
oriented, much later in the compression stroke, or even during the
combustion process, in order to increase charge density, to reduce
peak and overall combustion temperatures, and to create the desired
charge swirl turbulence in the combustion chamber(s).
[0127] One suggested, preferred method of operation of the
new-cycle engine 100.sup.4 is thus: [0128] 1. Depending upon the
power requirements of the engine (e.g., differing load
requirements), either intake air at atmospheric pressure or intake
air that has been compressed by one compressor (not shown) and has
had its temperature adjusted by bypass systems and charge-air
coolers (not shown) is drawn into the cylinder 7 (intake stroke)
through air inlet 9, manifold 14-B, intake conduits 15-B, and
intake valves 16a-B-16f-B by intake stroke of piston 22. [0129] 2.
(a) After the intake stroke is complete the intake valve 16-B
(which can be single or multiple), is left open for a period of
time after the piston 22 has passed bottom dead center, which pumps
part of the fresh air charge back into the intake manifold 14-B.
[0130] (b) Alternatively, the intake valve 16-B is closed early,
during the intake stroke before the piston reaches bottom dead
center. The trapped air charge is then expanded to the full volume
of the cylinder 7. [0131] 3. (a) The compression (2nd) stroke now
begins and, at the point the intake valve 16-B is closed to seal
cylinder 7 in either 2(a) or 2(b) operation, compression begins
(for a small compression ratio). This makes it possible to lessen
the temperature rise during the compression stroke. [0132] (b) When
greater power is required a secondary compressed,
temperature-adjusted air charge is injected into the cylinder 7 by
intake valve 16-A which opens and closes quickly during the
compression stroke at the point at which the intake valve 16-B
which introduced the primary air charge closes, or later in the
stroke, to produce a more dense, temperature controlled charge in
order to provide the torque and power desired of the engine. [0133]
(c) Alternatively, when greater power is required, the secondary
air charge can be increased in density and weight by causing
shutter valves 5 and 3 to direct all or part of the air charge
through one or more of intercoolers 10, 11 and 12 to increase the
charge density and/or by increasing compressor speed or by cutting
in a second stage of auxiliary compression, the latter two actions
thereby pumping in more air on the backside. Alternatively, the
timing of the closing of intake valve 16-B on either the inlet or
compression stroke can be altered temporarily to retain a larger
charge, and at the same time the timing of intake valve 16-A can be
temporarily altered to open and close earlier during the
compression stroke to provide a larger dense, temperature-adjusted
air charge. [0134] 4. Compression continues, fuel is added if not
present, the charge is ignited and combustion produces a large
expansion of the combusted gases against the piston 22 producing
great energy in either mode 3(a), (b), or (c). This energy is
absorbed and turned into high torque and power, especially in mode
(c). [0135] 5. Near bottom dead center of the piston, exhaust
valves 17a-17f, 17a'-17f' open and the cylinder 7 is efficiently
scavenged by the (4th) stroke of piston 22, after which valve(s) 17
close.
Detailed Description of the Operation of the Engine 100.sup.4 of
FIG. 4
[0136] During the intake (1st) stroke of the piston 22 low pressure
air flows through air conduit 15-B from the atmospheric air inlet 9
through manifold 14-B of air at atmospheric pressure or which has
been boosted in pressure (or, alternatively, the low pressure air
can be supplied by a pressure regulator valve 25 and conduit 15-B
from compressed air line 15-A as shown in FIG. 5), through an
intake valve 16-B into the cylinder 7. During the intake stroke of
piston 22, the intake valve 16-B closes (point x). From this point
the air charge in the cylinder is expanded to the maximum volume of
the cylinder. Then, during the compression (2nd) stroke, no
compression of the charge takes place until the piston 22 returns
to point x where the inlet valve was closed. (At point x, the
remaining displaced volume of the cylinder is divided by the volume
of the combustion chamber, establishing the compression ratio of
the engine.) At any point in the compression stroke of piston 22 at
the time or after the piston 22 reaches point x a second inlet
valve 16-A is, selectively, opened in order to inject a secondary
pressurized air charge at a temperature, density and pressure
deemed advantageous to the engine load, torque demand, fuel economy
and emissions characteristics desired. Alternatively, during the
intake of charge-air by intake valve 16-B, the intake valve 16-B is
held open past bottom dead center for a significant distance, 10%
to perhaps 50% or more of the compression stroke, thus pumping some
of the charge back into the intake manifold 14-B, and then closed
to establish a low compression ratio in the cylinder. During the
compression stroke, at or after the time intake valve 16-B is
closed, a secondary charge of high pressure, temperature-adjusted
air which has been compressed by compressor 2 is, selectively,
injected by a second intake valve 16-A, which opens and closes
quickly, into the same cylinder 7. Alternatively, when greater
torque and power are needed, the density of the secondary
charge-air is greatly increased by increasing the speed of the
primary compressor 2 or by cutting in another stage of compression,
as in item 1, FIG. 7, and/or by routing the air charge through
intercoolers.
[0137] For light-load operation a shut-off valve, or a valve
disabler 31 (such as shown in FIG. 7) on the high pressure intake
valve 16-A, preferably, temporarily restrains the intake air, or
holds the valve closed. This would add to the fuel economy of the
engine. Alternatively, during light-load operation the shutter
valve 5 is closed and the air bypass valve ABV 6 is opened so that
part or all of the air pumped by compressor 2 would be returned to
the inlet conduit of the compressor 2 for a low, or no pressure
boost. Therefore, when secondary intake valve 16-A opens, the
pressure of the air in conduit 15-A is approximately the same as,
or not much greater than that from the initial charge. In an
alternate embodiment, an ancillary automatic valve 26, FIG. 6, is
arranged, as shown in FIG. 6, to prevent any back-flow of
charge-air into conduit 15-A if the cylinder pressure should exceed
the pressure in conduit 15-A before intake valve 16-A closed during
the compression stroke of piston 22.
[0138] If an ancillary one-way valve (see valve 26 of FIG. 6) is
present, the pressure ratio in cylinder 7 can be fully controlled
by adjusting the pressure of the charge air passing through intake
valve 16-A. The pressure ratio can then be controlled by valves 3,
5, 6 and by compressor speed and any throttle valve that may be
present. In the use of valve 26, intake valve 16-A must be kept
open until very late in the compression stroke, perhaps until
piston 22 nears or reaches top dead center.
[0139] Fuel can be carbureted in FIG. 4, FIG. 4-B, FIG. 5, FIG. 7
and FIG. 33, injected in a throttle body 56 (seen in FIG. 16), or
the fuel can be injected into the inlet stream of air, injected
into a pre-combustion chamber or, injected through intake valves
16-A, 16-B, (16-B only if 16-B does not remain open past bottom
dead center), or it may be injected directly into the combustion
chamber at point x during the intake stroke, (during the intake
stroke only if intake valve 16-B closes before bottom dead center),
or at the time or after the piston 22 has reached point x in the
compression stroke. The fuel can be injected with or without
accompanying air. In the case of diesel operation, fuel can be
injected at the usual point for diesel oil injection, perhaps into
a pre-combustion chamber or directly into the combustion chamber or
directly onto a glow plug.
[0140] After the temperature-and-density-adjusting-air charge has
been injected, if used, compression of the charge continues and
with fuel present, is ignited at the opportune time for the
expansion (3rd and power) stroke. (The compression ratio is
established by the displaced volume of the cylinder remaining after
point x has been reached on the compression stroke, being divided
by the volume of the combustion chamber. The expansion ratio is
determined by dividing the cylinders total clearance volume by the
volume of the combustion chamber.) Now the fuel-air charge is
ignited and the power, (3rd) stroke of piston 22 takes place as the
combusted gases expand. Near bottom dead center of the power stroke
the exhaust valve(s) 17, 17' opens and the cylinder 7 is
efficiently scavenged on the fourth piston stroke by positive
displacement, after which exhaust valve(s) 17 closes.
[0141] This completes one cycle of the 4-stroke engine.
[0142] It can be seen that the later the point in the compression
stroke that point x is reached (the earlier or later the inlet
valve is closed), the lower is the compression ratio of the engine
and the less the charge is heated during compression. It can also
be seen that the later the temperature-density-adjusting charge is
introduced, the less work will be required of the engine to
compress the charge, the later part of which has received some
compression already by an ancillary compressor 2.
The Engine 100.sup.4-B of FIG. 4-B
[0143] Referring now to FIG. 4-B there is shown a six cylinder
4-stroke internal combustion engine similar in construction to the
engine of FIG. 4 with the exception that the engine of FIG. 4-B is
so constructed and arranged that compressor 2 receives charge-air
from manifold 14-B through opening 8-B (shown in FIG. 7) and
conduit 8 which air enters through common air intake duct 9. Intake
runners 15a-C to 15f-C distributes the atmospheric pressure air to
the intake valves 16-B of each power cylinder. This arrangement
allows the provision of air to intake valves 16-A and 16-B at
different pressure levels since the charge-air from conduits 15-A
is selectively pressurized by compressor 2. The operation of the
engine of FIG. 4-B is the same as that of the engine of FIG. 4.
The Engine 100.sup.5 of FIG. 5
[0144] Referring now to FIG. 5, there is shown a six cylinder
4-stroke internal combustion engine 100.sup.5 similar to the
engines 100.sup.4 of FIG. 4 and engine 100.sup.4-B of FIG. 4-B with
the exception that there are shown alternative ways that the dual
atmospheric air inlets can be eliminated, preferably by providing
the low pressure charge-air to intake valves 16-B by way of
conduits 15a-D to 15f-D all leading from the common air inlet
conduit 8, or from an optional air manifold 35-M, situated between
inlet conduit 8 and the inlet of conduits 15a-D to 15f-D, which
manifold would also supply air to compressor 2 through conduit 8-A.
Providing the low pressure charge-air to intake valve 16-B by way
of conduit 15-D, or by conduit 15-B (shown in phantom) would
eliminate a second air filter and air induction system and would
work well with either the first system described which involves
closing the primary intake valve 16-B during the intake stroke of
the piston 22 or alternatively closing the primary intake valve
16-B during the 2nd or compression stroke. Alternatively, as shown,
the low pressure charge-air can be supplied by placing a
pressure-dropping valve 25 in conduit 15-B routed for leading from
the pressurized air conduit 15 (15-A) to the low pressure cylinder
inlet valve 16-B in order to drop the inducted air pressure down to
the level that could be controlled by the system of compression
ratio adjustment described herein, preferably down to 1.5 to 2.0
atmospheres (absolute pressure which is a boost of 0.5 to 1.0
atmosphere) and perhaps down to atmospheric pressure.
[0145] The operation of the engine 100.sup.5 of FIG. 5 would be the
same as the operation of the engine 100.sup.4 of FIG. 4 although
the low pressure primary air supply is supplied differently.
Because of noticeable similarities between the engine 100.sup.5 of
FIG. 5 and that of FIG. 7, reference will be made as deemed helpful
to FIG. 7 for certain common components.
[0146] During light-load operation of this 4-stroke cycle engine
(FIG. 4, FIG. 4-B and FIG. 5) such as vehicle cruising or
light-load power generation, the secondary air charge is,
alternatively, eliminated by disabling high pressure intake valve
16-A temporarily (there are several valve disabling systems
available, e.g., Eton, Cadillac, etc.) or air can be shut off to
intake valve 16-A and the engine still produce greater fuel economy
and power than do conventional engines.
[0147] Alternatively and preferably, during light load operation
such as vehicle cruising, the compressor 2 can be relieved of any
compression work by closing the shutter valve 5 and opening the air
bypass valve 6 which circulates the air pumped back into the
compressor 2 and then the air in intake conduits 15-A and 15-B or
15-D are approximately equal. Therefore, no supercharging takes
place during this time. In one embodiment, automatic valve 26, FIG.
6, prevents back-flow of air during the compression stroke if
compression pressure in the cylinder approximates or exceeds the
pressure in conduit 15-A before the intake valve 16-A closes.
[0148] For increased power the secondary air charge may be
increased by shutter valves 3 and 5 being preferably opened to
direct the air charge to intercoolers 10, 11 and 12, which makes
the charge denser and/or by increasing the speed of compressor 2 or
by adding a second stage of pre-compression by compressor 1 in FIG.
7, the latter two actions thereby pumping in more air on the
backside. There is shown in FIG. 7 that the primary compressor 2 is
a Lysholm rotary type and a secondary compressor 1 is a rotary
compressor of the turbo type, although any type of compressors can
be used in the engines of this invention.
[0149] Referring now to FIG. 6 there is shown the same 4-stroke
engine and a similar operating system as described for the engines
of FIG. 4, FIG. 4-B, FIG. 5, FIG. 7 and FIG. 33, except that the
engine of FIG. 6 has an added feature in that the secondary intake
valve 16-A has an auxiliary valve 26 which is automatic to prevent
charge-air back-flow from cylinder 7. This feature will prevent any
back-flow from occurring during the compression stroke of the
engine of this invention. This feature can also be used to
establish the pressure ratio of the engine, either variable or
constant. If secondary charge air is being received through intake
valve 16-A, the intake valve 16-A can be kept open during the
compression stroke to near top dead center of piston 22, since
automatic valve 26 closes at such time the pressure in cylinder 7
approximates the pressure in intake runner conduit 15-A. Therefore,
the pressure differential between cylinder 7 and intake runner 15-A
will allow closure of automatic valve 26, even though intake valve
16-A may still be open, allowing the pressure ratio of cylinder 7
to be controlled by the pressure of any charge air coming through
intake runner 15-A, which in turn is controlled by valves 3, 5, and
6 and compressor speed and perhaps a throttle valve, if present,
for engines having a single stage of pre-compression. Valves 3, 4,
5 and 6 and compressor speed and any throttle valve present would
control the pressure ratios for engines having two stages of
pre-compression. If no charge is passing from intake valve 16-A,
automatic valve 26 will be already closed and the pressure ratio is
set by the compression ratio of the engine and the density and
temperature of the charge received by cylinder 7 through intake
valve 16-B. The compression ratio is still set by the point in
cylinder 7 that the primary intake valve 16-B is closed. The
pressure ratio is set by the density and temperature of the air
present in cylinder 7 whether it enters through valve 16-B, 16-A or
both, and by the compression ratio.
[0150] Any type of automatic valve can be used for item 26, perhaps
a spring-retracted disc type which can be made of metal or
ceramics.
The Engine 100.sup.7 of FIG. 7
[0151] Referring now to FIG. 7, there is shown a schematic drawing
of a six cylinder engine 100.sup.7 operating in a 4-stroke cycle.
The engine is similar in structure and operation to the 4-stroke
engine of FIG. 4, FIG. 4-B and FIG. 5 and shows alternative air
induction systems utilizing air intake 9 (in phantom) or air intake
8', or both. FIG. 7 also shows three intercoolers 10, 11 and 12 and
dual manifolds 13 and 14 plus alternative intake manifold 14-B. The
need for dual atmospheric air intake (8' and 9 in FIG. 7) can be
eliminated by providing air from port 8-B of manifold 14-B directly
to air intake conduit 8' shown schematically, in FIG. 7.
[0152] One alternate air induction system shown in FIG. 7 supplies
unpressurized charge-air to intake valve 16-B of the engine of FIG.
4-B and of FIG. 7 by providing atmospheric pressure air to the
intake runners 15a-C to 15f-C leading from manifold 14-B in FIG.
4-B and FIG. 7 which receives atmospheric air through induction
port 9, and then distributes the unpressurized air to intake valves
16-B of each power cylinder. Then, high pressure air enters through
intake valve 16-A after piston 22 has reached point x during the
compression stroke (the point in which intake valve 16-B closes and
compression begins). Intake valve 16-A then closes, compression
continues, fuel is added if not present and the charge is ignited
near top dead center (TDC) and the power (3rd) stroke occurs.
[0153] A second alternate air induction system shown in FIG. 7
supplies low pressure intake air as also shown in FIG. 5 of
alternatively receiving air from high pressure conduit 15-A through
conduit 15-B with the optional pressure reducing valve 25, (shown
in phantom in FIG. 5 and FIG. 7). The secondary high pressure air
charge is injected by intake valve 16-A at the same time or later
that the piston 22 reaches the point at which the intake valve 16-B
closes and compression begins. Intake valve 16-A then quickly
closes, compression continues, fuel is added if not present and the
charge is ignited at the appropriate place for the power (3rd)
stroke.
[0154] A third alternate and preferred air induction system shown
in FIG. 7 supplies the primary air charge to intake valve 16-B as
follows: Charge-air which has been pressurized to a low pressure by
compressor 1, perhaps from 0.3 Bar to as much as 2 Bar or more, can
selectively (and intermittently or continuously) be supplied to low
pressure intake valves 16-B of the engine of FIG. 7 by way of
conduit 32 leading from conduit 110 to the intake valves (16a-B
through 16f-B) which conduit receives charge-air at atmospheric
pressure or which has been pressurized and in any case has had its
temperature optimized, all controlled by compressor 1 and
intercooler 10 with the charge-air paths being controlled by valves
5 and 6 with the corresponding conduits. In this case the valve 33
is optional. After cylinder 7 has been charged and the compression
ratio established by the closing of intake valve 16-B during the
first or second stroke of piston 22, the high pressure intake valve
16-A opens on the compression stroke at the point which valve 16-B
closes, to inject the dense, temperature adjusted air charge and
then it closes, as compression continues and near top dead center,
fuel being present, the charge is ignited and the power (3rd)
stroke occurs. The use of this system also eliminates the need for
dual atmosphere air intakes.
[0155] A fourth alternate air induction system shown in FIG. 7
supplies the primary charge-air to the low pressure intake valves
16-B by having charge-air coming selectively from intake system 9,
manifold 14-B and intake runners 15-C (shown in phantom) or from
conduit 32 which would direct air to power cylinder 7 at whatever
level of pressure and temperature was needed at any particular
time. With this arrangement, opening valve 33 at such a time that
compressor 1 was compressing the charge passing through it would
have the effect of increasing the density of the primary charge-air
which in this case could also have its temperature as well as it
pressure adjusted by compressor 1 and control valves 5 and 6. A
one-way valve 34 would prevent the higher pressure air escaping
through conduit 15-C. When less power was needed compressor 1 could
be "waste gated" by opening, partially or completely control valve
6 and closing shutter valve 5. Alternatively, valve 33 could be
closed by the engine control module (ECM) and the primary
charge-air would be drawn into cylinder 7 at atmospheric pressure
through intake duct 9 (shown in phantom). The piston 22 now begins
its second stroke, the intake valve 16-B now closes, if not closed
on the intake stroke, to establish the compression ratio and in all
cases the heavy secondary charge enters through valve 16-A which
opens at the time, or after, piston 22 has reached the point where
intake valve 16-B had closed, valve 16-A then quickly closes,
compression continues and the charge is ignited near top dead
center and the power (3rd) stroke occurs.
[0156] With this fourth alternate air induction system the low
pressure intake valve 16-B can (a) receive charge-air at
atmospheric pressure or (b) can receive charge-air which has been
compressed and cooled through conduit 32 or conduit 15-B. The high
pressure intake valve 16-A (which opens at the time, or later, at
which compression begins) can receive charge-air which (a) has been
compressed and cooled in a single stage by compressor 1 or
compressor 2, (b) has been compressed and cooled in two stages or
more to a very high density or (c) which has had its temperature
and pressure adjusted by control valves 5 and 6, all in order to
provide better management of combustion characteristics in regard
to power, torque and fuel economy requirements and in regard to
emissions control. By incorporating an optional one-way valve (see
valve 26 shown in FIG. 6), the engines of FIG. 4, FIG. 4-B, FIG. 5
and FIG. 7 could have either a constant or a variable pressure
ratio, the charge density, pressure, temperature and turbulence and
the time of closing of valve 26 being controlled by valves 3, 5 and
6 and by compressor speed and by any throttle valve present in
engines having one stage of pre-compression, and by the addition of
valve 4, in engines having two stages of pre-compression. In either
case the intake valve 16-A should be held open very late in the
compression stroke, perhaps to near top dead center of piston
22.
[0157] One advantage to compressing the charge-air going to the low
pressure intake valve 16-B in addition to highly compressing the
secondary air charge is that during much of the duty cycle of such
engines the charge density could be dramatically increased while
keeping peak pressures and temperatures low, for high mean
effective cylinder pressure. This system could provide all power
necessary for vehicular travel in hilly country with perhaps the
high pressure intake valves 16-A being deactivated by a valve
deactivator indicated by 31 in FIG. 7, or by compressor 2 and/or
compressor 1 being partially or wholly bypassed by control valves 3
and 4 and/or control valves 5 and 6 to vary the pressure and
temperature going into manifolds 13 and 14 and then to intake
valves 16-A. For utmost power, the valve deactivators could be
turned off or eliminated.
[0158] Also shown in FIG. 7 is a suggested engine control system
consisting of an engine control module (ECM) 27, two shutter valves
3 and 5, two air bypass valves 4 and 6, the optional pressure
reducing valves 25 (25a-25f) on air conduits 15-B (15a-B-15f-B),
and a scheme of controlling the pressure, temperature and density
by controlling air bypass valves 4 and 6 and shutter valves 3 and
5. As illustrated, air bypass valve 4 is closed to allow compressor
2 to fully compress the charge and shutter valve 3 is slightly open
allowing part of the air to flow uncooled (hollow arrows) and some
of the air cooled (solid arrows) to the manifolds 13 and 14, all of
which could be controlled by the ECM 27 in order to provide an air
charge at optimum density, temperature and pressure. The hollow
arrow 4-A in conduit 120 shows how ABV 4 can be partially opened to
allow some of the air to bypass and return to compressor 2 in order
to finely adjust the pressure of the secondary air charge that is
injected to adjust the charge density and temperature.
Alternatively, all of the air charge can be directed through the
intercoolers 10, 11 and 12 or through bypass conduits 121 and 122,
to the manifolds 13 and 14.
[0159] For high power with a low compression ratio and low
polluting emissions, the air bypass valves (ABV) 4 and 6 are closed
and the shutter valves 3 and 5 would be opened so that the
compressors 2 and 1 raise the pressure of the air charge which is
directed by shutter valves 3 and 5 through the intercoolers for
maximum density. During the intake stroke the low pressure intake
valve 16-B opens, piston 22 sucks in low pressure air, the intake
valve 16-B closes before bottom dead center or after bottom dead
center during the compression stroke. During the compression
stroke, at the point the intake valve 16-B closed or later, intake
valve 16-A opens to inject the secondary, dense, cooled air charge
and then closes. Compression continues for a low compression ratio.
Fuel is added, if not present, and the charge is ignited at the
appropriate point near top dead center, (ignition can be before,
at, or after top dead center) for the power (3rd) stroke with a
large expansion ratio with high torque, then exhaust valve(s) 17
open and the scavenging (4th) stroke occurs, after which exhaust
valve(s) 17 closes.
[0160] In these designs, fuel can be carbureted, throttle body
injected, port injected, injected into the cylinder and can be
introduced at any point between the air intake and the piston
crown. The fuel air mixture can be stratified, or from a
stoichiometric to a very lean mixture for spark ignition, to a very
rich mixture for diesel operation. The engine power can be
controlled by fuel metering alone or the air supply can be properly
adjusted to the proper fuel-air ratio by a throttle valve or can be
"metered" by control valves 4 and 6 when using two stages of
pre-compression and by control valve 4 when using a single stage of
pre-compression.
[0161] In any of the engines of this invention, the problem common
to normal engines of incomplete mixing of fuel, air and residual
gas, with consequent variation in conditions at the ignition point
is minimized and in some cases eliminated by the late air charge
injection at high velocity. This problem, hereby addressed by the
present invention, is extreme in current engines when gaseous fuel
is injected directly into the cylinder where the spark may occur in
mixtures of varying fuel-air ratios, hence with various rates of
flame development.
[0162] (Concerning the importance of finding a solution to this
particular problem, engine researchers at Massachusetts Institute
of Technology state "The elimination of cycle-to-cycle variation in
the combustion process would be an important contribution to
improved [engine] performance. If all cycles were alike and equal
to the average cycle, maximum cylinder pressures would be lower,
efficiency would be greater, and most of all, the detonation limit
would be higher, thus allowing appreciable increase in efficiency
and/or mean effective cylinder pressure with a given fuel.")
[0163] The cyclic variation spoken of is minimized and,
potentially, eliminated in the engine of each of the embodiments
(including two-stroke embodiments and four-stroke embodiments) of
the current invention by the significant swirl turbulence produced
by the injection of high-pressure air. In addition, in any of the
engines of this invention the swirl turbulence can be oriented
tangentially to the cylinder wall by shrouding the inlet valve 16,
and especially valve 16-A, or by the use of a one-way valve (such
as valve 26 in FIG. 6 and FIG. 10). Even engines that receive an
air charge during the intake stroke of the piston using a shrouded
intake valve have a tendency to reduce unwanted cyclic variation
and have a decrease in octane requirement and an increase in
knock-limited indicated mean effective (cylinder) pressure
(klimep). The engine of the present invention, by injecting the
charge-air, especially through a shrouded valve during the
compression stroke, creates a much greater swirl turbulence to
further eliminate unwanted cycle-to-cycle variation for cleaner,
more complete combustion of the fuel.
[0164] The intake valve can rotate during operation and still have
a flow tangential to the cylinder wall by using a conventional
poppet valve and having the side of the valve head which is
opposite the desired direction of the air flow being shrouded as it
opens by a thickened section of the face of the engine's head
forming a crescent shaped collar or projection to direct the air
flow in the desired direction while the valve is open.
[0165] In the diesel combustion system, the better mixing process
of the present invention allows much richer fuel-air ratios for
greater smoke-limited power, and smoke and particulates are
virtually eliminated to an extremely rich fuel-air ratio.
[0166] The swirl turbulence produced by high pressure charge
injection during the compression stroke is not dampened by the
compression stroke and the later the charge is injected, the
smaller the volume of charge required to produce the desired swirl
turbulence. In any reciprocating internal combustion engine
operating in accordance with the method of the present invention, a
very high pressure, temperature-controlled air charge can,
selectively, be injected tangentially oriented, very late in the
compression stroke, for example, just prior to, during or with fuel
injection and, with extremely high pressures, even during the
combustion process.
[0167] Since the secondary air charge in the engine of FIG. 4
through FIG. 7, FIG. 9, FIG. 9-B and FIG. 15 through FIG. 20 is
compressible to an extremely high level of pressure, the intake
valve 16-A is, in alternate embodiments, replaced by a more
controllable and fast-acting valve, such as, but not limited to, a
high-speed solenoid valve (not shown). This valve is, preferably,
operated either mechanically, electrically or by vacuum and is,
preferably, controlled by an engine control module (ECM) as
illustrated in FIG. 7, FIG. 9-B, FIG. 15 through FIG. 20 and FIG.
33. In this system the secondary air charge can, selectively, be
injected very late in the compression stroke of piston 22 in order
to increase charge density, and swirl turbulence, and to reduce
peak and overall combustion temperatures and to lessen the
production of polluting emissions. The injection could be performed
in a tangentially oriented fashion. This would greatly increase
swirl turbulence and prevent undesirable cyclic variations which
are common in normal engines and most troubling in gaseous or
diesel fueled engines.
[0168] The use of this system should result in lower maximum
cylinder pressures and temperatures. Efficiency should be greater
and the detonation limit higher, thus allowing an appreciable
increase in efficiency and mean effective cylinder pressure with a
given fuel. All of the engines of this invention operate with a
more complete expansion process as compared to the typical prior
art engines, thereby providing further improvements in efficiency
and emissions characteristics.
[0169] In accordance with the present invention, the 4-stroke
engines of the present invention (for example, FIG. 1, FIG. 2, FIG.
3, FIG. 4, FIG. 4-B, FIG. 5, FIG. 7 and FIG. 33) are designed, as
are the 2-stroke engines of the present invention (for example,
FIGS. 8-11, 25 and 33), to use an expansion ratio larger than the
compression ratio. In order to accomplish this result, the
expansion ratio is set by selecting the appropriate
combustion-chamber volume and the compression ratio is reduced
below this value by very early or very late closing of the inlet
valve.
The Engine 100.sup.8 of FIG. 8
[0170] Referring now to FIG. 8, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.1 for gasoline,
diesel, alcohol, natural gas, hydrogen or hybrid dual-fuel
operation and having six cylinders 7a-7f (only one, 7f, is shown in
a sectional view) in which the pistons 22a-22f are arranged to
reciprocate. Another cylinder is indicated only by the presence of
the lower end of the cylinder liner 7a. A cut-a-way view shows a
double-acting compressor cylinder 1. Pistons 22a-22f are connected
to a common crankshaft 20 in a conventional manner by means of
connecting rods 19a-19f, respectively. The engine 100.sup.8 of FIG.
8 is adapted to operate in a 2-stroke cycle so as to produce six
power strokes per revolution of the crankshaft 20. To this end
compressor 1 takes in an air charge at atmospheric pressure, (or
alternatively an air charge which previously had been subjected to
compression to a higher pressure via an admission control valve 6
through an intake conduit 102, leading from compressor 2 by way of
bypass control valve 6 and shutter valve 5 and bypass conduit 104
or through the intercooler 10). During operation of the engine of
FIG. 8, the air charge is compressed within the compressor 1 by its
associated piston 131, and the compressed charge is forced through
an outlet into a high-pressure transfer conduit 109 which leads to
bypass valve 3 which is constructed and arranged to channel the
compressed charge through intercoolers 11 and 12 or through bypass
conduit 111 in response to signals from the engine control module
(ECM) 27. This module directs the degree of compression, the amount
and the direction of the flow of the compressed charge through the
intercooler and/or the bypass conduit into manifolds 13 and 14.
Manifolds 13 and 14 are constructed and arranged to distribute the
compressed charge by means of branch intake conduits 15a-15f and to
inlet valves 16 and 16', and to the remaining five power cylinders.
Alternatively, an ancillary compressor 2 receives atmospheric air
through inlet opening 8, pre-compresses the air charge into conduit
101 leading to control valve 5 which in response to signals from
ECM 27 will direct the compressed charge through intercooler 10 or
bypass conduit 104 to compressor 1. The ECM 27 can also control
valves 4 and 6 to direct part or all of the charge passing through
compressors 1 and 2 back through conduits 120 and 103 in order to
adjust the amount of compression of compressors 1 and 2 ranging in
either or both compressors from full compression to no compression,
thus during light-load operation either compressor 1 or compressor
2 could supply the needed compressed air to the cylinders.
[0171] The Engine 100.sup.8 of FIG. 8 has camshafts 21 which are
arranged to be driven at the same speed as the crankshaft in order
to supply one working stroke per revolution for the power pistons.
The reciprocating compressor can have one or more double-acting
cylinders one is pictured 1 and can have more than one stage of
compression, and the crankshaft 20 would supply two working strokes
per revolution, for one or more compressors, as described
hereinafter. The reciprocating compressor could alternatively be
driven by a short crankshaft which would be rotated by a step-up
gear on the main crankshaft driving a smaller gear on the ancillary
crankshaft. The ancillary rotary compressor 2 could be driven by
V-pulley operated by a ribbed V-belt and could have a step-up gear
between the V-pulley and the compressor drive shaft. The rotary
compressor 2 could also have a variable speed drive as in some
aircraft engines.
Description of the Operation of the Engine 100.sup.8 of FIG. 8.
[0172] Charge-air is induced into the inlet opening 8 of compressor
2, from there it passes through the compressor 2 where the charge
is then inducted into conduit 101 to shutter valve 5 where the
charge is directed either through intercooler 10 or through air
bypass valve 6 where a portion or all of the charge can be directed
back through the compressor 2 where the charge is re-circulated
without compression, or valve 6 can direct the air charge into the
inlet of compressor 1 where the air charge is pumped out the outlet
duct of compressor 1 which leads to shutter valve 3 where the
charge is directed either through intercoolers 11 and 12 or through
air bypass valve 4 or a portion through both, leading to manifolds
13 and 14 which distribute the charge-air to the intake valves 16
and to the intake valve of each power cylinder 7 of the engine 100.
(Bypass valve 4 can direct part or all of the air charge to
manifolds 13 and 14, or can recirculate part or all of the air
charge through conduit 120 back to conduit 106 and into the inlet
of compressor 1.) The engine control module (ECM) 27 controls
valves 3, 4, 5, and 6, in order to adjust the pressure, temperature
and density of the charge that is inducted into the engine's
combustion chambers 130. The same ECM 27 can control a
variable-valve-happening control system to adjust the time of
opening and closing of the inlet valves 16 and exhaust valves 17 of
the power cylinders in relationship to the angle of rotation of
crankshaft 20, in order to adjust the compression ratio and charge
density of the engine for optimum performance in regard to power,
torque, fuel economy and characteristics of fuel being
supplied.
The Operation of the Power Cylinder 7 is in this Manner:
Alternate Method 1:
[0173] Near the end of the power stroke in cylinder 7, the exhaust
valve(s) 17, 17' open and, with the exhaust valve still open, the
piston 22 begins the second or exhaust stroke. During the exhaust
stroke, perhaps as early as 70.degree. to 60.degree. before top
dead center the exhaust valves 17, 17' close. At the point the
exhaust valves are closed the compression ratio is established, the
intake valves 16, 16' are opened at that point or later in the
compression stroke, the compressed air and/or air-fuel charge is
injected into the combustion chamber 130 of the power cylinder 7,
intake valve 16, 16' closes at perhaps 60.degree. before top dead
center, with the swirl and squish turbulence accompanying the
high-pressure air injection, the piston 22 continues towards the
end of its stroke thus compressing the charge producing a very low
compression ratio, which can be as low as 2:1. If fuel is not
already present as a mixture, fuel is injected into the incoming
air stream or it is injected into a pre-combustion chamber or
directly into the combustion chamber after closure of the intake
valve. The fuel can be injected into the midst of the charge swirl
for a stratified charge combustion process, or it can be injected
onto a glow plug if diesel fuel is to be ignited. The fuel-air mix
is ignited by compression or spark, the latter at the opportune
time for greatest efficiency and/or power. Generally, the fuel
would be injected and ignited before top dead center of the piston.
The fuel can be injected later and perhaps continuously during the
early part of the expansion stroke for a mostly constant-pressure
combustion process and especially for diesel fuel. The fuel air
mixture is ignited preferably before the piston reaches top dead
center and the combusted charge expands against the piston as it
moves toward bottom dead center. At near bottom dead center of the
piston stroke, the exhaust valve(s) is opened and the exhausted
mixture is scavenged by positive displacement by the piston 22
during the scavenging stroke. If the intake valve 16, 16' is opened
earlier some valve overlap with the exhaust valve may be required
for scavenging. If the intake valves 16, 16' are opened late no
valve overlap would be needed, exhaust valve(s) 17, 17' closing at
approximately the same time that intake valve(s) 16, 16' open. The
expansion ratio of the engine could be about 19:1, for diesel fuel,
14:1 for gaseous fuel or gasoline, which expansion ratio is
established by dividing the cylinder displacement volume by the
volume of the combustion chamber.
Alternate Operation Method 2:
[0174] Near the end of the power stroke in cylinder 7 the exhaust
valve(s) 17, 17' open, and with exhaust valve 17, 17' still open,
begins its second or scavenging-charging stroke. At a point near
mid-stroke, (e.g., about 90.degree. before top dead center,) the
exhaust valve 17, 17' still being open, the intake valve opens with
a small valve overlap to admit high pressure scavenging and
charging air. One or more intake valves 16 can be recessed, as in
item 30 in FIG. 11, in order to direct the first inlet air down and
along the cylinder 7 wall in order to loop-scavenge the cylinder
during the very small overlap of valves 16, 16' and 17, 17'. The
exhaust valve 17, 17' remains open to the point at which
compression should begin and then receives the air charge as it
closes, intake valve(s) 16, 16' closing soon after, with the
cylinder adequately scavenged and charged with temperature-adjusted
fresh air now at high pressure. The piston 22 continues its stroke
to compress the charge producing a low compression ratio, ideally
13:1 to 4:1, depending on the type of fuel used. The compression
ratio is established by the point in the stroke of piston 22 in
which the exhaust valve(s) 17, 17' closes, and is calculated when
the remaining displaced volume of the cylinder is divided by the
volume of the combustion chamber.
[0175] As piston 22 continues to rise from point x, where the
exhaust valve closes establishing the compression ratio, and where
compression of the charge started, the pressure starts to rise at
the same point. The dense cooled air charge with the short
compression stroke will produce a low compression ratio with a very
heavy charge, with low maximum cylinder pressure but with high
effective mean cylinder pressure for great torque and power.
[0176] The pressure ratio will be established by the density,
pressure and temperature of the incoming charge, the length of time
inlet valve(s) 16, 16' are open and the point the exhaust valve(s)
17, 17' closes. The later the exhaust valves 17, 17' close, the
less the charge-air expands after injection, the less work is
required to compress the charge and the less overlap of inlet and
exhaust valve is required and the lower is the compression
ratio.
[0177] At some point, perhaps as early as 150-120 degrees before
piston top dead center position, cylinder 7 would be adequately
scavenged and the exhaust valve 17, 17' could be closed before, or
no later than, the time the intake valves 16, 16' are opened to
admit, in this case, the entire air charge, most of the exhausted
gases having been displaced by scavenging. (In some cases some
residual exhaust gases are beneficial and experiments will show at
what point both intake and exhaust valves can be closed without any
overlap.) In this instance the "effective" compression ratio could
be as low as 3:1 or even 2:1, again producing low maximum cylinder
pressure and temperature but with high mean effective pressure.
Fuel can be injected as early as at the point the exhaust valve
closes and can be as early as about 150.degree.-120.degree. before
the end of the compression stroke. The fuel-air mixture is ignited
before, at, or after, top dead center and the expansion (2nd)
stroke takes place. The expansion ratio is established by dividing
the cylinder's displaced volume by the combustion chamber volume
and could be about 19:1 for diesel applications, and 14:1 for
gasoline or gaseous fuels.
[0178] An engine control module (ECM) 27 can manage temperatures
and densities of the charge being introduced into the cylinder 7 or
combustion chamber 130 and the timing of the inlet into the
combustion chamber and can thus adjust charge densities,
turbulence, temperatures and pressures providing a means of
restraining peak temperatures and pressures yet with a mean
effective cylinder pressure higher than in a normal engine, when
needed, and further providing for lower levels of unwanted
polluting emissions.
[0179] A suggested light-load, fuel efficient operation system as
indicated on line B(bp) in FIG. 13, would be thus: A nominal
compression ratio of 13:1 could be chosen, with an expansion ratio
of 19:1. The latter would establish the volume of the combustion
chamber, the former would establish the maximum charge pressure
(not maximum cylinder pressure), about 530 psi when compressed
adiabatically. The ECM 27 would signal shutter valves 5 and air
bypass control valve 6 to re-circulate the air being pumped through
compressor 2, back through the compressor 2 without being
compressed or for any type compressor, open a waste-gate valve to
bypass the compressor. Shutter valve 5 bypasses the intercooler 10
and directs the charge into the inlet of compressor 1. Compressor 1
would compress the charge adiabatically to say, 7:1 compression
ratio. ECM 27 controls would bypass intercoolers 11 and 12 and
introduce the charge into manifolds 13 and 14 with the
heat-of-compression retained. If the exhaust valves 17, 17' are
closed and the inlet valve 16, 16' of cylinder 7 are opened near
the end of the compression stroke of piston 22 the effective
compression ratio can be as low as 2:1, producing a "nominal"
compression ratio of 14:1. (If the exhaust valves 17, 17' are
closed and the inlet valve 16, 16' are opened earlier in the
exhaust stroke, the injected charge-air should be of lower pressure
and the "effective" compression ratio, that in-cylinder compression
producing heat, would be greater. If the intake valves 16, 16'
opened at mid-stroke, after exhaust valves 17, 17' close, and a
nominal compression ratio of 13:1 were desired with an effective
compression ratio of 4:1, then the charge introduced into the
cylinder at mid-stroke should be compressed 4:1.) The uncooled
charge is then compressed in the cylinder with an effective
compression ratio of 4:1, and in either case, with a pressure of
about 530 psi and a temperature above 900.degree. F. The fuel/air
charge is then ignited and expanded against the piston to the full
volume of the power cylinder with an expansion ratio of 19:1.
[0180] At such a time that great power was required, the ECM 27
could signal the air bypass valve 4 and 6 to close. Compressor 2
then begins to compress the air charge to a higher pressure, at the
same time ECM 27 would open shutter valves 3 and 5 to send the
charge-air through the intercoolers 10, 11 and 12. Therefore, as
the charge-air is cooled, and could be to as low as 150-200.degree.
F., more air is now pumped into the engine on the back side by the
additional compression stage 2, to prevent a substantial pressure
drop in the charge-air due to the cooling of the charge before
combustion. The air charge in the combustion chamber is now
compressed 2:1 (line B(ic), FIG. 13) and is maintained near the
design pressure, in this case about 500-530 psi, although cooled,
to significantly increase the density of the charge and the torque
and power of the engine. The cooler air charge provides lower peak
temperature and pressure and coupled with the high turbulence
causes production of less unburned hydrocarbons, NO.sub.x and other
polluting emissions and with smoke and particulates being virtually
eliminated to a very rich fuel-air mixture. The air-fuel charge is
now ignited and expanded to the full volume of the cylinder with an
expansion ratio of 19:1 although the effective compression ratio is
only 2:1 (see line B (ic) in FIG. 13).
[0181] With either operation scheme the engine can be supercharged
to a higher state than can conventional engines because in most
cases the inlet valve is closed at the time of combustion chamber
charging and a cooler air charge prevents detonation and reduces
polluting emissions. Also in most cases residence time of the fuel
is less than that required for pre-knock conditions to occur.
[0182] When less power is needed, as during vehicle cruising or
light-load power generation, the engine operation could revert to
light-load operation, e.g., one stage of compression could be cut
out and the first cooler 10 bypassed by the air charge being
re-circulated by shutter valve 5 and by bypass valve 6. Shutter
valve 3 and air bypass valve 4 could direct all of the charge from
compressor 1 passed intercoolers 11 and 12 with the
heat-of-compression retained, into manifolds 13 and 14 and to the
cylinder for the less dense, more fuel efficient operation
mode.
[0183] Still referring to FIG. 8, there is shown a view of a
cylinder head of the engine of FIG. 8 through FIG. 11 and FIG. 25,
showing optional pressure balanced intake valves with cooling being
provided by conduits with intake conduit 29 and outlet conduit 29',
one-way valves (not shown) which allow expansions 28 on the valve
stems, as they reciprocate with intake valves 16 to pump a cooling
and lubricating oil or oil-air mixture through the spaces above the
valve stem expansions.
[0184] Pressure-balanced intake valves 16, 16' in FIGS. 8, 11, and
25, and 16-A in FIGS. 9 and 10 provide for rapid intake valve
closure and allows large non-restricting intake valves and smaller
than normal valve return springs. (When the intake valve is opened,
pressure equilibrium almost immediately takes place below the valve
head within the combustion chamber and above the valve head within
the intake runner, then the pressure in the intake runner acting on
the piston-like arrangement on the valve stem tends to cause the
valve stem to follow the down-slope of the cam profile for rapid
valve closure. Also, a new "Magnavox" pressure operated, "square
wave" intake valve could be used in the engines of this
invention.)
[0185] The operation of the pressure balanced intake valves is in
this manner:
[0186] The pressure balanced intake valves have expansions 28 on
the valve stems, the lower surface of which are exposed to gases in
conduit 15A. When the valve stem is depressed by a cam 21 and
intake valve(s) 16 opens in FIG. 8 through FIG. 11, or FIG. 25 any
pressure in conduit 15A is equilibrated with pressure in the
combustion chamber and at that time the only reactive force is by
any pressure in conduit 15A which is against the underside of valve
stems expansions 28, causing a rapid closure of the valve. One-way
valves (not shown) on inlet and outlet channels 29 and 29' are
preferably provided for oil or oil-air mixture induction through
spaces above expansions 28, and alternatively through the valve
stem expansions 28. The oil inlet could be at a low point in the
cylinder head where oil would collect to supply the cooling system.
Alternatively, oil inlet line 29 could be connected to an oil or
oil-air mix supply line. The inlet conduit 29 and the exit conduit
29' from the cooling system would be fitted with one-way valves and
the exit conduit 29' could be higher than the inlet conduit 29 or
could be connected to an oil discharge line leading to the engine
oil reservoir. The valve stem expansions 28 could also have a
channel through them with a one-way valve on each side. Since
historically exhaust valves have been difficult to cool, this same
system would provide adequate cooling for the exhaust valves even
though there is not great pressure in the exhaust conduit. This
system would then be applied to exhaust valves 17 from which
exhaust ports 18 originate, or to the exhaust valves of any engine
to provide long life for the exhaust valves and the valve
seats.
[0187] On large engines the lines from the pumps described here can
converged into larger lines and the oil pumping provided by them
could replace the conventional oil pump on said engine.
The Engine 100.sup.9 of FIG. 9
[0188] Referring now to FIG. 9, there is shown a six cylinder
reciprocating internal combustion engine having one atmospheric air
intake, in which all of the cylinders 7a-7f (only one (7f) is shown
in a sectional view) and associated pistons 22a-22f operate in a
2-stroke cycle and all power cylinders are used so as to produce
six power strokes per revolution of crankshaft 20 for producing
power to a common crankshaft 20 via connecting rods 19a-19f,
respectively. A primary compressor 1, in this figure a
double-acting reciprocating type, is shown which, with air conduits
as shown, supplies pressurized air to one or more cylinder intake
valves 16-A and 16-B (the latter only if a primary charge to valve
16-B comes from conduit 15). A secondary compressor 2 of the
Lysholm type is shown in series with compressor 1. An air inlet 8
and associated compressors 1 and/or 2 with inlet conduits and
manifolds 13 and 14 supply charge-air, which has been compressed to
a higher than atmospheric pressure, to the air intake runner 15-A
and intake valve 16-A to cylinder 7. A second conduit 32 directs an
air charge from conduit 110 through optional shut-off valve 33 to
intake valve 16-B to supply lower pressure air to the same
cylinder. Alternatively a second conduit 15-B from conduit 15-A can
be fitted with a pressure control valve 25 (both in phantom) and
can direct the lower pressure air charge to the intake valve 16-B.
Intercoolers 10, 11 and 12 and control valves 3, 4 5 and 6 are used
to help control the density, weight, temperature and pressure of
the charge air. The intake valves are timed to control the
compression ratio of the engine. The combustion chambers are sized
to establish the expansion ratio of the engine.
[0189] The engine of FIG. 9, FIG. 11 and FIG. 25 have cam shafts 21
fitted with cams and are arranged to rotate at engine crankshaft
speed in order to supply one power stroke for each power piston for
each crankshaft rotation.
[0190] The engine 100.sup.9 shown in FIG. 9 is characterized by a
more complete expansion process and a lower compression ratio than
typical engines, and is capable of producing a combustion charge
varying in weight from lighter-than-normal to heavier-than-normal
and capable of selectively providing a mean effective cylinder
pressure higher than can the conventional arrangement in normal
engines with similar or lower maximum cylinder pressure. Engine
control module (ECM) 27 and variable valves 3, 4, 5 and 6 on
conduits as shown provide a system for controlling the charge
pressure, density, temperature, and mean and peak pressure within
the cylinder which allows greater fuel economy, production of
greater power and torque at all RPM, with low polluting emissions
for both spark and compression ignited engines. In alternate
embodiments, a variable valve timing system with the ECM 27 can
also control the time of opening and closing of the intake valves
16-A or 16-B or both, to further provide an improved management of
conditions in the combustion chamber to allow for a flatter torque
curve, higher power and with low levels of both fuel consumption
and polluting emissions.
[0191] Brief Description of Operation of Engine 100.sup.9 Shown in
FIG. 9
[0192] The new cycle engine 100.sup.9 of FIG. 9 is a high
efficiency engine that attains both high power and torque, with low
fuel consumption and low polluting emissions.
[0193] The new cycle is an external compression type combustion
cycle. In this cycle part of the intake air (all of which is
compressed in the power cylinders in conventional engines) is
compressed by at least one ancillary compressor. The temperature
rise at the end of compression can be suppressed by use of air
coolers, which cools the compressed air, and by a shorter
compression stroke.
[0194] During operation air is supplied to an intake valve 16-B of
the power cylinder 7 which has been increased in pressure by
perhaps one-third to one atmosphere or more through an air intake
conduit 32 leading from ancillary compressor 2, or the air enters
by conduit 15-B and a pressure control valve 25. A second air
conduit 15A selectively supplies charge-air at a higher pressure to
a second intake valve 16-A leading to the same power cylinder 7.
(In this design the intake valve 16-B admits the low pressure air
after exhaust valves 17 open near bottom dead center in the power
stroke, and exhaust blowdown has occurred.) Exhaust blowdown occurs
after exhaust valve(s) 17 open and now intake valve 16-B opens and
closes quickly to inject low pressure scavenging air. The cylinder
7 is further scavenged by loop scavenging as piston 22 begins its
compression stroke. Intake valve 16-B is now closed and piston 22
rises in the compression stroke to the point where compression
should begin at which point exhaust valve 17 closes sealing
cylinder 7 and establishing the compression ratio. Compression
continues and at near top dead center, at a point deemed
appropriate, fuel being present, the charge is ignited by spark or
compression and the power stroke takes place.
[0195] When more power is desired, a secondary air charge from
conduit 15-A can be introduced into the power cylinder at the time
of, or after closure of exhaust valve(s) 17a during the compression
stroke, by intake valve 16-A which introduces a higher pressure air
charge, and quickly closes, in order to increase the charge
density. Alternatively, the primary air charge may be boosted to a
higher pressure by adjusting air bypass valve 6 to send more air
through compressor 2, by increasing the speed of compressor 2 or by
changing the setting on the control valve 25 on the conduit 15-B
which alternatively supplies the low pressure primary air charge to
intake valve 16-B. The temperature, pressure, amount and point of
injection of a secondary charge, if added, is adjusted to produce
the desired results.
[0196] For light-load operation an intake valve disabler 31 (there
are several on the market, for example, Eaton Corp. and Cadillac)
can disable intake valve 16-A when light-load operation does not
require a high mean effective cylinder pressure. Alternatively,
during the time the low pressure air to intake valve 16-B is
supplied by conduit 15-B the air bypass valve (ABV) 6 can be opened
to re-circulate some of the charge-air back through the compressor
2 in order to relieve the compressor of compression work during
light-load operation. Additionally, and preferably, air bypass
valve 4 can re-circulate part or all of the air pumped by
compressor 1 back to the inlet of compressor 1 on demand in order
to reduce pressure and density of the secondary charge going
through intake valve 16-A.
[0197] One suggested, preferred method of operation of the
new-cycle engine 100.sup.9 is thus: [0198] 1. Intake air at greater
than atmospheric pressure that has been compressed by at least one
compressor 2 and has had its temperature adjusted by bypass systems
or charge-air cooler 10, is introduced into the cylinder 7 through
intake valve 16-B, which is opened by a small lobe on cam 21-B at
near bottom dead center, at the end of the power stroke (perhaps at
bottom dead center) after exhaust valve(s) 17, 17' have opened
earlier say, at 40.degree. before bottom dead center, for exhaust
blowdown. The exhaust valves remain open after bottom dead center
for further scavenging of the cylinder 7. The intake valve 16-B
closes at near bottom dead center. [0199] 2. After the power stroke
is complete and cylinder 7 is filled with fresh charge, the exhaust
valve(s) 17 is left open for a period of time after the piston has
passed bottom dead center (with intake valve 16-B now closed) in
order to further scavenge the power cylinder with the fresh air
charge present and further, in order to establish a low compression
ratio of the engine, the compression ratio being established by the
displaced cylinder volume remaining at the point of the exhaust
valve 17 closure, being divided by the volume of the combustion
chamber. [0200] 3. With the cylinder 7 now filled with fresh air,
the compression (2nd) stroke continues and, at some point the
exhaust valve 17 is closed and compression begins for a small
compression ratio. This makes it possible to lessen the temperature
rise during the compression stroke. Compression continues, fuel is
added if not present, and the charge is fired a the appropriate
point near top dead center and the power stroke occurs. [0201] 4.
(a) Alternatively, when greater power is required, a secondary
compressed, temperature-adjusted air charge is injected into the
cylinder 7 by intake valve 16-A opening and quickly closing during
the compression stroke at the point at which the exhaust valve
closes, or later in the stroke, to produce a more dense charge in
order to provide the torque and power desired of the engine. [0202]
(b) When even greater power is required, the secondary air charge
can be increased in density and weight by being passed through one
or more intercoolers 10, 11 and 12 and by increasing compressor
speed or by cutting in another stage of auxiliary compression or by
passing more of the charge air through the operational compressors.
[0203] 5. Near bottom dead center of the piston position, exhaust
valves 17, 17' open and the cylinder is efficiently scavenged by
blowdown and by the air injected by primary intake valve 16-B.
Detailed Description of the Operation of the Engine 100.sup.9 of
FIG. 9
[0204] Near the end of the power (1st) stroke of the piston 22,
perhaps at about 40.degree. before bottom dead center position of
piston 22, the exhaust valves 17 open for exhaust blowdown, shortly
after low pressure air flows through air conduit 32 from conduit
106 and optional shut-off valve 33 and compressor 2 or
alternatively through air conduit 15-B supplied by a pressure
regulator valve 25 from compressed air line 15-A (as shown in FIG.
9, and FIG. 10), through an intake valve 16-B into the cylinder 7.
Intake valve 16-B closes shortly after bottom dead center or,
perhaps at bottom dead center. Exhaust valves 17 remain open during
the first part of the compression (2nd) stroke of piston 22. The
cylinder 7 is now efficiently scavenged by blowdown and by loop
scavenging and at any point during the compression stroke, the
cylinder 7, now filled with fresh air, the exhaust valves 17, 17'
can close. But since a low compression ratio is desired, the
exhaust valves 17, 17' can be held open until the piston has
reached the point that is desired to establish the compression
ratio. At, or after the time exhaust valves 17a and 17a' are
closed, a secondary charge of high pressure, temperature adjusted
air which has been compressed by a compressor(s) can be injected by
intake valve 16-A into the same cylinder, after which intake valve
16-A closes. In addition, when very high torque and power is
needed, the density of the secondary charge-air can be greatly
increased by cutting-in compressor 2 or by increasing the speed of
compressor 2, if already compressing, as in FIG. 9, directing more
air through compressors 1 and/or 2 by valves 4 and/or 6, and by
routing the charge wholly or in part through intercoolers 10, 11
and 12.
[0205] In this system, regardless of the point the exhaust valve is
closed to establish the compression ratio, the primary fresh air
charge trapped in the cylinder 7 will be lighter than normal and
the compression ratio will be lower than normal, therefore, if
needed, a highly compressed, temperature adjusted air charge can be
injected at exhaust valve closure or later in the stroke, to
provide a heavier than normal charge but with the temperature rise
being restrained by the cooled charge and the short compression
stroke. This produces a greater than normal mean effective cylinder
pressure when combusted for great torque and power but still with
an expansion ratio greater than the compression ratio.
[0206] For light-load operation a shut-off valve, or a valve
disabler 31 (in phantom) on the high pressure intake valve could
temporarily restrain the intake air, or hold the valve 16-A closed.
This would add to the fuel economy of the engine. Alternatively, if
compressor 2 is not supplying air to conduit 32 and intake valve
16-B, during light-load operation the shutter valve 5 could be
closed and the air bypass valve 6 can be opened so that air pumped
by compressor 2 would be returned in part or wholly to the inlet
conduit of the compressor 2 with little or no compression taking
place there.
[0207] An ancillary automatic intake valve 26, FIG. 10, can be
arranged, as shown in FIG. 10, to prevent any back-flow of
charge-air into conduit 15-A if the cylinder 7 pressure should
approximate or exceed the pressure in conduit 15-A during the
compression stroke of piston 22 before the closure of intake valve
16-A.
[0208] Alternatively, the ancillary automatic valve 26 of FIG. 10
could be used to provide a constant or a variable pressure ratio in
cylinder 7. In this case valve 16-A would be kept open to near top
dead center and the closure time of valve 26 would be adjusted by
the pressure differential in cylinder 7, controlled by valves 3, 4,
5 and 6 by compressor(s) output and by any throttle valve present.
The automatic valve 26 could be of the spring-retracted disc type
and could be fabricated of metal or ceramics.
[0209] Fuel can be carbureted, injected in a throttle body 56,
shown in FIG. 15 through FIG. 17 and item 56 in FIG. 19 and FIG.
20, or the fuel can be injected into the inlet stream of air,
injected into a pre-combustion chamber (similar to that seen in
FIG. 21) or, injected through intake valves 16-A, or it may be
injected directly into the combustion chamber at point x during the
exhaust-compression stroke, at the time or after the piston 22 has
passed point x in the compression stroke. The fuel can also be
injected later and in the case of diesel operation can be injected
at the usual point for diesel oil injection, perhaps into a
pre-combustion chamber or directly into the combustion chamber,
perhaps as FIG. 21, or directly onto a glow plug. After the
temperature-and-density-adjusting-air charge has been injected, if
used, compression of the charge continues and with fuel present, is
ignited at the opportune time for the expansion stroke. (The
compression ratio is established by the displaced volume of the
cylinder remaining after point x has been reached, being divided by
the volume of the combustion chamber. The expansion ratio is
determined by dividing the cylinders total clearance volume by the
volume of the combustion chamber.)
[0210] Now the fuel-air charge is ignited and the power (2nd)
stroke of piston 22 takes place as the combusted gases expand. Near
bottom dead center of the power stroke the exhaust valve(s) 17, 17'
open and the cylinder 7 is efficiently scavenged by blowdown and by
loop scavenging at the end of the power stroke and largely during
the piston 22 turnaround time.
[0211] It can be seen that the later the point in the compression
stroke that point x is reached (the later the exhaust valve is
closed), the lower is the compression ratio of the engine and the
less the charge is heated during compression.
[0212] It can also be seen that the later the
temperature-density-adjusting charge is introduced, the less work
will be required of the engine to compress the charge, the later
part of which has received some compression already by compressor 1
and/or by an ancillary compressor 2. In some cases where the load
is light and fuel economy important the ancillary compressor could
be bypassed with the secondary air charge perhaps eliminated
temporarily and the total charge weight could be less than that of
a conventional engine and with the extended expansion ratio produce
even better fuel economy.
[0213] During light-load operation of this 2-stroke cycle engine
(FIG. 9 and FIG. 9-B) such as vehicle cruising or light-load power
generation, the secondary air charge can be eliminated by disabling
high pressure intake valve 16-A temporarily (several valve
disabling systems Eton, Cadillac, etc.) or air can be shut off to
intake valve 16-A and the engine still produce greater fuel economy
and power with the air charge being supplied by compressor 2 or 1
through conduits 15-A, 110, 32 and intake valve 16-B.
The Engine 100.sup.9-B of FIG. 9-B
[0214] FIG. 9-B is a schematic representation of a six-cylinder
reciprocating internal combustion engine 100.sup.9-B which is for
the most part identical to the engine 100.sup.9 of FIG. 9. The
characteristics and operation and structure of the engine
100.sup.9-B of FIG. 9-B are substantially similar to the engine
100.sup.9 of FIG. 9 and, except as necessary to point out specific
points of distinction, such characteristics, operation and
structure are not repeated here. Reference should be made to the
sections on characteristics, structure and operations (both brief
and detailed) previously presented with respect to the engine
100.sup.9 of FIG. 9.
[0215] The major point of distinction between engine 100.sup.9 and
engine 100.sup.9-B is that engine 100.sup.9-B represents an
embodiment of the engine 100.sup.9 wherein the compressors 1,2 are
of alternate types. That is, in 100.sup.9-B, the primary compressor
1 is shown as a Lysholm rotary compressor (as opposed to the
reciprocating-type compressor of engine 100.sup.9) and the
secondary compressor 2 is of the turbo-type (as opposed to the
Lysholm-type of 100.sup.9). Although conduit 32 from conduit 110
(designated as 106 in FIG. 9) and optional shut-off valve 33 is
shown supplying intake valves 16-B of only two cylinders of the
engine, it is understood that other intake runners (not shown)
distribute air from conduit 110 to the remainder of the intake
valves 16-B of the engine, or that conduit 32 supplies an "air box"
or manifolds which distribute the air to all of the intake valves
16-B.
[0216] Referring now to FIG. 10 there is shown the same engine and
the same operating system as described for the engines of FIG. 9
and FIG. 9-B, but has an optional added feature in that the
secondary intake valve 16-A has an ancillary valve 26 which is
automatic to prevent charge-air back-flow from cylinder 7. This
feature will prevent any back-flow from occurring during the
compression stroke of the engine of this invention, should the
cylinder pressure approximate or exceed the pressure in conduit
15-A before the intake valve 16-A was fully closed. (This optional
automatic valve 26 could be of the spring-retracted disc type, or
could be any type of one-way valve.) An automatic valve at this
place could be used to regulate the pressure ratio in cylinder 7
during the compression of the charge. In this case intake valve
16-A could be kept open to near top dead center, valve 26
automatically closing the intake below valve 16-A during
compression, ignition and power stroke of the charge. Furthermore,
the use of automatic valve 26 would allow the pressure ratio of the
engine to be adjusted by simply adjusting the pressure in conduit
15-A, with intake valve 16-A being kept open to near top dead
center of piston 22. The ancillary valve 26, if present, would also
impart a tangentially oriented swirl turbulence to the combustion
charge as would also, shrouding of intake valve 16-A.
The Engine 100.sup.11 of FIG. 11
[0217] Referring now to FIG. 11, there is shown a six cylinder
reciprocating internal combustion engine 100.sup.11 with one
atmospheric air intake, in which all of the cylinders 7a-7f (only
one (7f) of which is shown in a sectional view) and associated
pistons 22a-22f operate in a 2-stroke cycle and all power cylinders
are used for producing power to a common crankshaft 20 via
connecting rods 19a-19f respectively. A primary compressor 1, in
this figure a double-acting reciprocating type, is shown which,
with an air conduits, as shown, supplies pressurized air to one or
more cylinder intake valves 16a and 16b. A secondary compressor 2
of the Lysholm type is shown in series with compressor 1. An air
inlet 8 and associated inlet conduit and manifolds 13 and 14 supply
air charge which has been compressed to a higher than atmospheric
pressure, to a cylinder intake conduit 15 which supplies charge-air
to two intake valves, which intake valves 16a and 16b operate
independently of each other but open into the same cylinder.
Intercoolers 10, 11 and 12 and control valves 3, 4, 5 and 6 are
used to help control the air charge density, weight, temperature
and pressure. The intake valves are timed to control the
compression ratio of the engine. The combustion chambers are sized
to establish the expansion ratio of the engine.
[0218] The engine 100 of FIG. 8, FIG. 9, FIG. 10 and FIG. 11 have
cam shafts 21 fitted with cams and are arranged to rotate at engine
crankshaft speed in order to supply one power stroke for each power
piston for each crankshaft rotation.
[0219] The engine 100.sup.11 shown in FIG. 11 is characterized by a
more extensive expansion process, a low compression ratio and
capable of producing a combustion charge varying in weight from
lighter-than-normal to heavier-than-normal and capable of
selectively providing a mean effective cylinder pressure higher
than can the conventional arrangement in normal engines, but having
similar or lower maximum cylinder pressure. Engine control module
(ECM) 27 and variable valves 3, 4, 5 and 6 on conduits, as shown,
provide a system for controlling the charge pressure, density,
temperature, and mean and peak pressure within the cylinder which
allows greater fuel economy, production of greater power and torque
at all RPM, with low polluting emissions for both spark and
compression ignited engines. In alternate embodiments, a variable
valve timing system with the ECM 27 can also control the time of
opening and closing of the intake valves 16a or 16b or both, to
further provide an improved management of conditions in the
combustion chamber to allow for a flatter torque curve, and higher
power, with low levels of both fuel consumption and polluting
emissions.
Brief Description of Operation of Engine 100.sup.11 shown in FIG.
11
[0220] The new cycle engine 100.sup.11 of FIG. 11 is a high
efficiency engine that attains both high power and torque, with low
fuel consumption and low polluting emissions.
[0221] The new cycle is an external compression type combustion
cycle. In this cycle part of the intake air (all of which is
compressed in the power cylinders in conventional engines) is
compressed by an ancillary compressor. The temperature rise at the
end of compression can be suppressed by use of air coolers, which
cools the intake air, and by a shorter compression stroke.
[0222] During operation air is supplied to the power cylinder 7 at
a pressure which has been increased by perhaps from one-third to
several atmospheres, or greater through an air intake conduit 15.
Valve 16b opens by pressure on the top of the valve stem from a
very small lobe on cam 21-A for a short period of time near bottom
dead center position of piston 22 in order to scavenge the cylinder
and provide fresh charge-air. Exhaust valves 17, 17' open for
exhaust blowdown slightly before intake valve 16b opens to admit
scavenging air. The cylinder 7 is efficiently scavenged mostly
during the turnaround time of piston 22. During the first part of
the compression stroke, perhaps as early as 10-20.degree. after
bottom dead center of piston 22 position, the first intake valve
16b closes, at a later time the exhaust valve 17, 17' closes, at
which point compression of the fresh air charge starts, which
establishes the compression ratio of the engine. At the point the
exhaust valves 17, 17' closes or any point later, the second intake
valve 16a and perhaps 16b, by a second lobe 21-C is, preferably,
opened to introduce more of the temperature and density adjusted
charge, if needed.
[0223] An intake valve disabler 31 in FIG. 10 (there are several on
the market, for example, Eaton Corp. and Cadillac) can disable
intake valve 16a when light-load operation does not require a high
mean effective cylinder pressure. Alternatively, the air bypass
valve (ABV) 6 is opened wholly or partially to re-circulate some or
all of the charge-air back through the compressor 2 in order to
relieve the compressor of compression work during light-load
operation. Additionally, air bypass valve 4 can re-circulate part
or all of the air pumped by compressor 1 on demand in order to
reduce charge pressure and density.
[0224] One suggested, preferred method of operation of the new
cycle engine 100.sup.11 is thus: [0225] 1. Intake air at greater
than atmospheric pressure that has been compressed by at least one
compressor and has had its temperature adjusted by bypass systems
and charge-air coolers are introduced into the cylinder 7 through
intake valve 16b which is opened by a very small lobe 21-D on cam
21-A at or near bottom dead center of piston 22 at the end of the
power-stroke, as exhaust valve(s) 17a, 17a' have opened a little
earlier (perhaps 40' before bottom dead center) for exhaust
blowdown. The exhaust valve 17 remains open through bottom dead
center for efficient scavenging of the cylinder 7 by blowdown and
loop scavenging. Intake valve 16b closes as the fresh high-pressure
charge very quickly scavenges the cylinder 7. [0226] 2. After the
power stroke is complete the exhaust valves 17 are left open for a
period of time after the piston has passed bottom dead center (with
intake valve 16b now closed) in order to continue to scavenge the
power cylinder 25 with the fresh air charge and further, in order
to establish a low compression ratio of the engine, the compression
ratio being established by the displaced cylinder volume remaining
at the point of the exhaust valve 17 closure being divided by the
volume of the combustion chamber. [0227] 3. With the cylinder 7 now
filled with fresh air which is near atmospheric pressure, the
compression (2nd) stroke continues and, at the point the exhaust
valve is closed, compression begins for a small compression ratio.
This makes it possible to lessen the temperature rise during the
compression stroke. Compression continues, fuel is added, if not
present, and the charge is fired at the appropriate point near top
dead center and the power-stroke occurs. [0228] 4. (a)
Alternatively, at any point deemed appropriate at the time or after
the exhaust valve has closed and compression of the charge has
begun, a secondary density and temperature-adjusted air charge can
be injected through intake valve 16a and perhaps by a second lobe
21-C on cam 21-A, through intake valve 16b. Compression continues
with the secondary air charge injection, fuel is added, if not
present, the charge is ignited and combustion produces a large
expansion of the combusted gases producing great energy. This
energy is turned into high torque and power by the engine. [0229]
(b) When even greater power is required, the air charge can be
increased in density and weight by being passed through one or more
intercoolers and by increasing compressor speed or by cutting in a
second stage 2 of auxiliary compression, FIG. 11. Alternatively,
the timing of closing exhaust valve 17 and of the opening of intake
valve 16a could be altered temporarily to close earlier and to open
earlier, respectively, for a larger charge. [0230] 5. Near bottom
dead center of the piston, exhaust valves 17, 17' open and the
cylinder is scavenged by blowdown and by the air injected by
primary intake valve 16b.
Detailed Description of the Operation of the Engine 100.sup.11 of
FIG. 11
[0231] Near the end of the power (1st) stroke of the piston 22,
perhaps at about 40.degree. before bottom dead center position of
piston 22, the exhaust valves 17 open for exhaust blowdown, shortly
after, high pressure air flows through air conduit from manifold 13
and 14, as shown in FIG. 11, through an intake valve 16b into the
cylinder 7, the cylinder 7 is scavenged, intake valve 16b closes.
(Intake valve head 30 can be recessed as shown in FIG. 11 in order
to form a pipe-like opening into cylinder 7 so that when the
charge-air is highly compressed, and as much as 500-530 psi is
feasible, the small lobe 21-D on cam 21-A of intake valve 16b lets
in a small blast of the high pressure air which is directed
downward for loop scavenging, during or just after piston 22
turnaround at bottom dead center piston position.) Exhaust valves
17 remain open during the first part of the compression (2nd)
stroke of piston 22. The cylinder 7 is now efficiently scavenged by
blowdown and by loop scavenging and at any point during the
compression stroke, the cylinder 7, now being filled with fresh
air, the exhaust valves 17, 17' can close. But since a low
compression ratio is desired, the exhaust valves 17, 17' can be
held open until the piston has reached the point that is desired to
establish the compression ratio. At, or after the time exhaust
valve 17 closed, a secondary charge of high pressure temperature
adjusted air which has been compressed by compressor 1 and/or 2 can
be injected by the second intake valve 16a and, if desired, by
another lobe 21-C (in phantom) on the first valve 16b into the same
cylinder. (When high torque and power is needed, the density of the
charge-air can be greatly increased by increasing the speed of the
primary compressor 1 or by cutting in another stage of compression,
as in compressor 2, FIG. 11, and routing the charge through
aftercoolers 10, 11 and 12. Also the speed of compressor 2 can be
increased to shove in more charge on the back end.) Compression
would continue, for a small compression ratio, fuel would be added,
if not present, the charge would be ignited and the gases expanded
against piston 22 for the power stroke.
[0232] For light-load operation, a shut-off valve (or a valve
disabler 31 shown in FIG. 10 on the intake valve 16-A) could
temporarily restrain the intake air, or hold the intake valve 16a
closed. This would add to the fuel economy of the engine.
Alternatively, during light-load operation the shutter valve 5
could be closed and the air bypass valve 6 opened so that air
pumped by compressor 2 would be returned to the inlet conduit of
the compressor 2 without any compression taking place. In the same
manner valves 3 and 4 could return part of the air being pumped
through back to the intake 106 of compressor 1.
[0233] The ancillary automatic intake valve 26, FIG. 10, which can
be of the spring-returned disc type, can be arranged, as shown in
FIG. 10, to prevent any back-flow of charge-air into conduit 15 if
the cylinder pressure should equal or exceed the pressure in
conduit 15 during the compression stroke of piston 22 before intake
valve 16a had closed completely. (As in other engine designs herein
presented, the optional automatic valve 26 shown in FIG. 10 can be
utilized to control the pressure ratio of this engine. If the
intake valve 16a is kept open to near top dead center, the closure
of valve 26 and the pressure ratio of cylinder 7 would be
controlled by control valves 3, 4, 5 and 6 and by compressor speed
and by any throttle valve present.) Automatic valve 26 would seal
the intake from conduit 15 during the last part of the compression
stroke, ignition of the charge and during the power stroke.
[0234] Fuel can be carbureted, injected in a throttle body 56 in
FIG. 15 through FIGS. 17, and 56 in FIGS. 19 and 20, or the fuel
can be injected into the inlet stream of air, or injected into a
pre-combustion chamber or, injected through intake valves 16a, 16b,
(the latter during its second opening by lobe 21-C on cam 21-A), or
it may be injected directly into the combustion chamber at or past
point x in the exhaust-compression stroke. The fuel can also be
injected later and in the case of diesel operation can be injected
at the usual point for diesel oil injection, perhaps into a
pre-combustion chamber or directly into the combustion chamber or
directly onto a glow plug. After the
temperature-and-density-adjusting-air charge has been injected, if
used, compression of the charge continues and with fuel present, is
ignited at the opportune time for the expansion stroke. (The
compression ratio is established by the displaced volume of the
cylinder remaining after point x (at exhaust valve closure) has
been reached, being divided by the volume of the combustion
chamber. The expansion ratio is determined by dividing the
cylinders total clearance volume by the volume of the combustion
chamber.) Now the fuel-air charge has been ignited and the power
stroke of piston 22 takes place as the combusted gases expand. Near
bottom dead center of the power stroke, the exhaust valve(s) 17
opens and the cylinder 7 is efficiently scavenged, first by
blowdown, then by loop scavenging by air from intake valve 16b at
the end of the power stroke or shortly after.
[0235] It can be seen that the later the point in the compression
stroke that point x (the later the exhaust valve is closed) is
reached, the lower is the compression ratio of the engine and the
less the charge is heated during compression.
[0236] It can also be seen that the later the
temperature-density-adjusting charge is introduced, the less work
will be required of the engine to compress the charge, the later
part of which has received some compression already by compressor 1
and/or by an ancillary compressor 2. In some cases where the load
is light and fuel economy important the ancillary compressor could
be bypassed with the secondary air charge perhaps eliminated
temporarily and the total charge weight could be less than that of
a conventional engine.
[0237] Referring now to FIG. 12 there is shown a pressure-volume
diagram for a high-speed Diesel engine compared to the engines of
this invention, showing three stages of intercooled compression and
a fourth stage of uncooled compression indicating a compression
ratio of approximately 2:1, which arrangement is suggested for
optimum power, with efficiency for the engine of this invention.
(The charts of FIG. 13 and FIG. 14 show some of the improvements of
the engine of this invention over current heavy-duty 2-stroke and
4-stroke engines.)
[0238] There are several features that improve the thermal
efficiency of the engine of this invention. Greater power to weight
ratios will provide a smaller engine with less frictional losses.
The extended expansion ratio results in higher thermodynamic cycle
efficiency, which is shown in theoretical considerations. There are
also definite efficiency gains in a "staged" compression process
even with external compressors with associated piping, intercoolers
and aftercoolers, etc. There is a very significant energy savings
when air is compressed in intercooled stages. Less energy is used
in compressing a charge to 500 psi in 2, 3 or 4 intercooled stages
than is used to compress the hot charge to the same 500 psi in a
conventional engine. A normal engine uses approximately 20% of its
own energy produced to compress its own air charge. Calculations
show a significant energy savings in an engine if the air is
compressed in aftercooled stages. Compressing a charge in only two
stages to 531 psi (a 13:1 compression ratio) reduces the energy
used by 15.8% over compressing to the same 531 psi level in a
single stage as does the Otto and the Diesel Cycle engines. Three
stages of intercooled compression raises the savings to 18%. This
is the ideal. Degradation from the ideal should not exceed 25%
which leaves a 13.5% energy savings. This 13.5% energy savings
times the 20% of a normal engine's power used for compressing its
own charge, is a 2.7% efficiency improvement by the compression
process alone. This is one of the advantages of this engine which
adds to the other thermal efficiency improvements. The low
compression ratio, along with the large expansion ratio provides
improvements in efficiency, torque, power and durability while
lowering polluting emissions. [0239] Note 1--In FIG. 12 the travel
distance of the line for engine B on the horizontal coordinate
indicates the theoretical volume at the greater density. The
density is kept at that level at the actual combustion chamber
volume (as shown by dashed line V) regardless of the density, by
pimping in more charge at the back-side.
[0240] Referring now to FIG. 13, there is shown a chart which
compares various operating parameters of the engine of this
invention (B) with the operation parameters of a popular
heavy-duty, 2-stroke diesel cycle engine (A).
[0241] The parameters shown for engine A are the normal operating
parameters for that engine, e.g., compression ratio, combustion
temperatures, charge density, etc. The parameters chosen to
illustrate for engine (B) are given at two different lower
"nominal" compression ratios with corresponding "effective"
compression ratios, intercooled and uncooled, for two different
levels of power output. The columns showing charge densities and
expansion ratios indicate the improvements in steady state power
density improvements for engine B even at a substantially lower
nominal compression ratio and an effective compression ratio as low
as 2:1 as shown in FIG. 10. The columns showing low temperatures at
the end of combustion, and the column showing extended expansion
ratios indicate much lower polluting emissions. Indicated power
improvements of engine (B) over engine (A) even at the lower
nominal compression ratio are no less than 50%.
[0242] Referring now to FIG. 14 there is shown a chart which
compares the various operating parameters of the engine of this
invention (B) with the operating parameters of a popular heavy-duty
4-stroke diesel engine (A).
[0243] When comparisons similar to those of FIG. 13 are made,
steady state power and density improvements are much higher since
engine (B) fires the denser charge twice as often as engine A for
an indicated steady-state power density improvement of 180% over
engine (A).
[0244] Referring now to FIG. 15, there is shown a schematic drawing
of an engine representing the engines of FIGS. 5-7, and FIGS. 9-10
with a separate air cooler 10 for ancillary compressor 2, with the
primary compressor 1 supplying two manifolds 13 and 14 and having
separate air coolers 11 and 12 and charge-air conduits 114 and 115,
and having each manifold having three cylinder air intake runners
15a-15c, 15d-15f, respectively. The engine of FIG. 15 operates the
same as the engines of FIGS. 5-7 and FIGS. 9-10 and here shows
suggested valving positions for shutter valve and air bypass valves
for supplying the manifolds 13 and 14 with an air charge optimum
for light-load operation of the engine of FIGS. 5-7 and FIGS. 9-10.
For light-load operation, the shutter valve 5 can be closed and the
air bypass valve 6 of compressor 2 (if compressor 2 is not
supplying primary air charge directly to conduit 32 and intake
valve 15-B) can be opened fully or partially so that part or all of
the intake air of compressor 2 can be returned to the intake of
compressor 2 with little or no compression occurring there. Also,
the shutter valve 3 of compressor 1 can be closed, passing the air
charge away from the coolers 11 and 12, the air bypass valve 4
would be closed to prevent re-circulation of the now compressed and
heated air back through compressor 1 and whose shutter valve 3 and
air bypass valves are both directing the air charge uncooled into
manifold 13 and 14 for a low density heated charge for light-load
operation. Preferably compressor 2 would be kept operative in order
to supply the primary air charge through conduits 110, 32 and
intake valve 16-B for a more economical scavenging-charging
system.
[0245] Referring now to FIG. 16, there is shown suggested valve
positions for supplying manifolds 13 and 14 with an air charge
optimum for medium-load operation for engines of FIG. 16 or for the
engines of FIGS. 5-7 and FIGS. 9-10. For medium-load operation the
shutter valve 5 of compressor 2 is closed and the air bypass valve
6 would be opened to pass the air charge uncooled and without
compression to the intake of compressor 1 where closed shutter
valve 3 and closed air bypass valve 4 directs the air charge now
compressed by compressor 1 past the intercoolers to manifolds 13
and 14 with the air compressed and heated by compressor 1, for
medium-load operation.
[0246] Referring now to FIG. 17, there is shown a suggested
scenario for providing the engine of FIG. 17 or for the engines of
FIGS. 5-7 and FIGS. 9-10 with a high density air charge for heavy
duty, high power output operation. FIG. 17 shows both shutter
valves 3 and 5 open and both air bypass valves 4 and 6 closed
completely so that the primary stage of compression is operative
and a second stage of compression has been made operative for
maximum compression of the charge and the entire air charge is
being passed through the intercoolers 10, 11 and 12 to produce a
cooled, very high density air charge to manifolds 13 and 14 and to
the engines power cylinders for heavy-load operation. This produces
a very high mean effective cylinder pressure for high torque and
power with maximum cylinder pressure being the same as, or lower
than that of normal engines.
[0247] Referring now to FIG. 18, there is shown a schematic drawing
of an alternative type of auxiliary compressor 2' for the engines
of FIGS. 5-7 and FIGS. 9-10 and for any other engine of this
invention and a system of providing a system for cutting out the
auxiliary compressor when high charge pressure and density is not
needed. For relieving compressor 2' of work, (if the air compressed
by compressor 2 does not go directly to conduit 32 and valve 16-B
to supply the primary air charge) shutter valve 5 is closed and air
bypass valve 6 is opened so that air pumped through compressor 2'
can re-circulate through compressor 2, thus relieving the
compressor of compression work.
[0248] Referring now to FIG. 19, there is shown a schematic drawing
of the engines of FIGS. 5-7 and FIGS. 9-10, illustrating means of
controlling charge-air density, temperature and pressure by varying
directions of air flow through various electronic or vacuum
operated valves and their conduits.
[0249] FIG. 19 also shows the various charge-air paths possible by
using hollow arrows to indicate heated air paths and solid arrows
to indicate the more dense intercooled air paths thereby indicating
how charge-air temperatures can be thermostatically or
electronically controlled by dividing the air charge into two
different paths. Alternatively, all of the air charge can be
directed past the air coolers or all can be directed through the
air coolers, as shown in FIG. 19. Also, FIG. 19 shows how the
pressure output of compressor 1 and compressor 2 can be varied by
partially or fully opening air bypass valves 4 and 6 or by
completely closing one or both of these control valves. An engine
control module (ECM) 27 is suggested for controlling the various
operating parameters of the engines of this invention.
[0250] Referring now to FIG. 20, there is shown is a schematic
drawing depicting an alternate arrangement in which an electric
motor 34 preferably drives the compressor(s) of any of the engines
of the present invention.
Charge-Air Cooler Bypass (ACB) "Shutter Valve" Control
[0251] In this section are described aspects of preferred control
components which find application in connection with any of the
engines (4-stroke and 2-stroke) of the present invention.
Outline: Valves 3 and 5 are charge-air-cooler bypass solenoid (ACB)
valves. In charge-air cooler bypass control, the intake air is
switched between two routes by valves 3 and 5, independently of
each other: either (a) valve 5 directs the flow from compressor 2
directly to the intake conduit of compressor 1 or (b) through the
charge-air cooler 10 before flowing to the intake conduit of
compressor 1. Valve 3 directs the flow from compressor 1 either (a)
to the conduit 111/121/122 leading directly to the intake manifolds
13 and 14 or (b) it passes the air charge through charge-air
coolers 11 and 12 before it flows to manifolds 13 and 14.
[0252] An engine control module (ECM) 27 can control the air cooler
bypass valves 3 and 5. The bypass valves may be a shutter type
valve to pass all or none of the air charge in either direction or
valves 3 and 5 may be of a helical solenoid or other type of valve
which can pass part of the air charge through bypass conduits 121
and 122 and part through air coolers 10, 11 and 12 for fine control
of the temperature and density of the air charge. The ECM could
receive signals from sensors such as an engine coolant sensor, a
crankshaft position sensor, throttle position sensor, camshaft
position sensor, a manifold absolute pressure sensor and a heated
oxygen sensor.
Air Bypass Valve (ABV) Control
[0253] Outline: To provide optimum air charging pressure for
differing engine operations conditions, the ECM 27 can send signals
to control air bypass valves 4 and 6. These valves could be on-off
solenoid valves, possibly vacuum operated, or they could be helical
solenoids or other type of valve which could open part way or all
way in order to re-circulate part or all of the air charge back
through the inlets 110 and 8 of compressors 1 and 2 in order to
reduce or eliminate entirely the pumping pressure of either
compressor 1 or compressor 2, or both. Similar arrangements of air
pressure control could be used for additional stages of air
compression if additional stages are used.
[0254] The operation could be thus: The ABV valves 4 and 6 can be
controlled by signals from the ECM 27 to control the opening angle
of valves 4 and 6 to provide the optimum air charging pressures for
various engine loads and duty cycles. When ABV 6 is opened
partially some of the air pumped through compressor 2 is passed
back into the intake 8 of compressor 2 to reduce compression
pressure. When ABV 6 is opened fully all of the charge of
compressor 2 is passed back through compressor 2, thus compressor 2
only pumps the charge through with no pressure increase. The system
can work the same for valve 4 which could bypass some of the air
charge pumped by compressor 1 back into the intake conduit 110 of
compressor 1 in order to reduce air charge density.
[0255] With this arrangement, combined with the arrangement of ECM
27 control of charge-air cooler bypass system for variable valves 3
and 5, the temperature, density, pressure and turbulence of the
charge-air can be managed to produce the desired power and torque
levels and emissions characteristics in the power cylinder of the
engine.
[0256] Engine conditions that could be monitored by ECM 27 in order
to effect proper engine conditions in regard to control of ABV
valves 4 and 6 could include a throttle position sensor (or fuel
injection activity sensor), intake air temperature sensor at
various points, manifold absolute pressure sensor, camshaft
position sensor, crankshaft position sensor, exhaust temperature
sensor, a heated oxygen sensor and/or other sensory inputs known to
be used in internal combustion engines.
[0257] The ECM 27 can control both the shutter valves 3 and 5 and
the air bypass valves 4 and 6 in order to maintain the optimum air
charging density pressure and temperature at all engine operating
duty cycles.
Alternate Combustion Systems
[0258] Referring now to FIG. 21, there is shown a schematic
transverse view of a pre-combustion chamber 38', a combustion
chamber 38, a piston crown 22 and associated fuel inlet 36, a
sparking plug 37, an air or air/fuel mixture inlet 8' duct, intake
valve 16, an exhaust duct 18' an exhaust valve 17 suggested for
liquid or gaseous fuel operation for the engines of this invention
or for any other internal combustion engine.
[0259] There are many choices of systems for compression or spark
ignition combustion for the engine of this invention, as shown in
FIG. 1 through FIG. 33. Every fuel from avgas to heavy diesel
fuels, including the alcohols and gaseous fuels can be spark
ignited (SI) in this engine. One good SI system would be similar to
the system shown in FIG. 21 for compressed natural gas, propane,
hydrogen, gasoline, alcohols or diesel fuel. In this system, an
extremely fuel rich mixture constituting the entire fuel charge is,
preferably, injected into the pre-combustion chamber 38'. The fuel
could be injected through fuel duct 36 with or without air blast
injection, the air charge, some of which can accompany the fuel
charge would be compressed into the pre-combustion chamber 38' by
piston 22 during the compression stroke. Additional air with or
without additional fuel, could be introduced into the cylinder
proper either on the intake stroke or on the compression stroke
through intake conduit 8'. In either case the second combustion
stage in the cylinder proper would be with a lean mixture.
The Two-Stage Combustion System Shown in FIG. 21 Will Operate in
this Manner:
1. Pre-Combustion (First Stage)
[0260] Pre-combustion occurs in the pre-combustion chamber 38' when
fuel-in an amount much in excess of the amount of oxygen present is
injected and ignited (injector not shown). This oxygen deficiency
along with the cooler, turbulent charge and lower peak temperatures
and pressures greatly reduces the formation of oxides of nitrogen.
The combination of the hot pre-combustion chamber wall and intense
turbulence promotes more complete combustion.
2. Post-Combustion (Second Stage)
[0260] [0261] Post-combustion takes place at lower pressure and
relatively low temperature conditions in the space above the piston
in the cylinder as the gases expand from the first stage
pre-combustion chamber into the cylinder proper. If there is
additional fuel in the cylinder proper, the leaner mixture is
ignited by this plasma-like blast from the pre-combustion chamber.
The low temperature and the admixture of burned gases prevent any
further formation of oxides of nitrogen. Excess air, a strong
swirling action, and the extended expansion process assure more
complete combustion of carbon monoxide, hydrocarbons, and
carbon.
[0262] The results of the engine of this invention using the
pre-combustion chamber 38' of FIG. 21 are: higher thermal
efficiencies due to the greater expansion, along with a cooler
exhaust and a lower level of polluting emissions including oxides
of nitrogen, and in addition for diesel fuels, lower aromatics and
particulates.
[0263] Referring now to FIG. 22 there is shown a schematic
transverse sectional view of an optional cylinder of the engine of
this invention which will convert the 2-stroke engine of FIG. 8
through 33 to a one-stroke cycle engine and will convert the
4-stroke engines of FIG. 1 through FIG. 7 and FIG. 33 to operate in
a 2-stroke cycle.
[0264] By building any 2-stroke engine with all power cylinders
double acting, the power to weight ratio can be doubled over the
basic engine. One end of the cylinder fires and the other end is
scavenged on each stroke for a nominal one stroke cycle engine in
the engines of FIG. 8 through FIG. 33. Use of double-acting power
cylinders in the 4-stroke engine of FIG. 1 through FIG. 7 and FIG.
33 converts the engine to a 2-stroke engine because one end of the
cylinder is scavenged and one end is fired during each crankshaft
rotation.
[0265] In the design of FIG. 22 needed variation of beam 39 length
is accomplished by the beam end forming a scotch yoke 40 and
fitting over the wrist pin 41 of the piston.
[0266] The double ended piston 22'' can be linked to the end of a
vertical beam 39 that pivots at the lower end 42. A connecting rod
19' is joined between the midpoint of the beam and the crankshaft
20'.
[0267] Since the crankshaft 20' itself does no more than transmit
torque, its main bearings will be very lightly loaded. As a result
little noise will reach the supporting casing. Because of the lever
action, the crank (not shown) has half the throw of the piston
stroke and can be a stubby, cam-like unit with large, closely
spaced pins having substantial overlap for strength.
[0268] The compression ratio can be changed by slightly lengthening
or shortening the effective length of the beam 39. This can be done
by the lower pivot plate 42 being attached to a block 43 mounted
slidably in a fixed block 44 and in which block 43 can be moved
slidably by a servo motor 45. The gear 45a rotated by servo motor
45 is much longer than the gear 44a on the screw 43b which is
rotatably attached to block 43 and rotates against threads in block
44, causing gear 44a to slide back and forth on gear 45a as block
43 reciprocates in block 44. Thus as a diesel, it could be started
at 20:1 ratio and then shifted to a 13:1 ratio for less friction
and stress on parts. This could also be important to allow use of
alternate fuels.
[0269] Referring now to FIG. 23: These same advantages hold true
for the alternate design (FIG. 23) in which the pivot 47' is
between the connecting rod 19 and the piston 22''
[0270] The needed variation of the length of the beam 39 (shown in
phantom) connecting the piston 22'' to the connecting rod 19 can be
accomplished by forming a scotch yoke 40 on the beam end fitting
over the wrist-pin 41 of the piston 22'', or by placing a double
pivoting link 42' between the pivot 47' on the fulcrum of beam 39'
with the pivot 42'' being attached to a non-movable part 46 of the
engine and the terminal end of beam 39' being connected to
connecting rod 19 by a pin 47.
[0271] Alternately and preferably, for heavy duty engines (marine
propulsion, power production, etc.) the power take off of piston
22'' could be with a conventional piston rod 39' being arranged
between piston 22'' and a crosshead 20' with a connecting rod 19'
between the crosshead 20' and the crankshaft (not shown).
[0272] Double-acting power cylinders when used in the engine of
this invention will be especially of importance where great power
is desired and cooling water is readily available, e.g., for marine
use or for power generation.
[0273] These double-ended, double-acting cylinders can be used in
all of the designs of this invention.
[0274] Referring now to FIG. 24: There is shown a schematic
transverse sectional view of a crankshaft, two connecting rods 19'
and 19'' and a beam 39 showing a means of providing extra burn time
of a conventional 2-stroke or 4-stroke engine.
[0275] This layout for any engine provides for double the piston
22' turnaround time of a normal engine during the critical burn
period. This is because piston 22' top dead center (TDC) occurs at
bottom dead center (BDC) of the crank 48. At this point, crankpin
motion around piston 22' top dead center is subtracted from the
straightening movement of the connecting rod 19', instead of being
added to it as in conventional engines. Reversing the usual action
slows piston travel around this point, resulting in more complete
combustion and further reducing emissions.
[0276] The extra burn time provided by the design of FIG. 24 can be
important in the engines of this invention and to any Otto or
Diesel cycle engine.
[0277] Operation of the engine constructed and arranged with the
additional burning time would be the same as the other engines of
this invention providing high charge density, low
compression-ratios with a mean effective pressure higher than
conventional engines but with more combustion time than other
engines while producing even less polluting emissions.
[0278] Since the crankshaft 48 in FIG. 24 itself does no more than
transmit torque, its main bearings will be very lightly loaded. As
a result little noise will reach the supporting casing. Because of
the lever action, the crank can have as little as half the throw of
the piston stroke (depending on the point of the fulcrum), and can
be a stubby, cam-like unit with large, closely spaced pins having
substantial overlap for strength.
[0279] This layout also provides for nearly twice the combustion
time of a conventional engine during the critical burn period. This
is because piston top dead center occurs at bottom dead center
(BDC) of the crank.
The Engine 100.sup.25 of FIG. 25
[0280] Referring now to FIG. 25 of the drawings, there is shown a
six cylinder reciprocating internal combustion engine in which all
of the cylinders 7a-7f (only one (7f) of which is shown in a
sectional view) and associated pistons 22a-22f are adapted to
operate in a 2-stroke cycle and all cylinders are used for
producing power to a common crankshaft 20 via connecting rods
19a-19f, respectively. A compressor 2 supplies air to scavenging
ports 52 by way of optional shut-off valve 33-M and conduit 32 and
to cylinder charge inlet valve(s) 16 and 16' by way of conduits 15.
The engine of FIG. 25 is adapted to operate in a 2-stroke cycle so
as to produce six power strokes per revolution of the crankshaft
20. To this end, compressor 1 takes in an air charge which may have
been previously subjected to compressing to a higher pressure, via
an admission control valves 5 and 6 through an intake conduit 110,
leading from compressor 2 by way of intercooler 10 or bypass
conduit 104 and shutter valve 5. During operation of the engine of
FIG. 25, compressor 2 receives atmospheric air through inlet
opening 8, pre-compresses the air charge into conduit 101 leading
to control shutter valve 5 which in response to signals from the
ECM 27, to shutter valve 5 and air bypass valve 6, will direct the
compressed charge through intercooler 10 or through cooler bypass
conduits 104 to compressor 1. The air charge is compressed within
compressor 1 by its associated piston 131, and the compressed air
charge is forced through an outlet into a high pressure transfer
conduit 109 which leads to control shutter valve 3 which, if open,
directs the air through intercooler 11 and 12 to manifolds 13 and
14 or, if closed, through a conduit and air bypass valve 4 which
can direct part of the air charge back through inlet conduit 104 of
the compressor 1, or valve 4 if fully closed, directs all of the
charge from compressor 1, in response to signals from the engine
control module (ECM) 27, through the intercoolers 11 and 12 or
through the bypass conduit 111/121/122 into manifolds 13 and 14.
Manifolds 13 and 14 are constructed and arranged to distribute the
compressed air charge by means of branch conduits 15a-15f to inlet
valves 16 and 16' of the cylinder 7a, and to the remaining five
power cylinders 7b-7f. In an alternate embodiment, instead of
providing scavenging air through conduit 32', scavending air is
provided through shut-off valve 49 and conduit 50 and pressure
reducing valve 25 to air box 51, through conduits 125a-125f to
scavenging ports 52a-52f.
[0281] The engine 100.sup.25 shown in FIG. 25 has a camshaft which
is arranged to be driven at the same speed as the crankshaft in
order to supply one working stroke per revolution for the power
pistons. The compressor can be reciprocating, comprised of one or
more stages of compression with one or more double-acting
cylinders, one is shown, 1 in FIG. 25. The compressor can be driven
by associated connecting rods 19g to crankshaft 20 which can have
throws of different lengths for different length piston strokes for
the air compressor(s) than those of the power pistons. In addition,
compressor 1 can be driven by a second crankshaft (not shown) which
is driven by a gear meshing with a step-up gear mounted on the
common crankshaft. The ancillary rotary compressor, a Lysholm type
is shown 2, can be driven by a V-pulley being rotated by a ribbed
V-belt and has a step-up gear arranged between the V-pulley and the
compressor drive shaft. The rotary compressor 2 could also have a
variable speed, or two speed drive, as in some aircraft
engines.
[0282] The operation of engine 100.sup.25 shown in FIG. 25 is thus:
Charge-air is inducted into the inlet opening 8 of compressor 2.
From there it is pumped through the compressor 2 where it is
directed by shutter valve 5 through the intercooler 10 or through a
conduit to air bypass valve 6 where it is directed to the inlet of
compressor 1. The charge is then pumped by compressor 1 through the
outlet valve to shutter valve 3 which directs the air charge either
through intercoolers 11 and 12, to manifolds 13 and 14 or into a
conduit leading to air bypass valve 4 which can direct a part of
the charge back through the inlet of compressor 1 or valve 4
directs the charge wholly or partially to the shutter valve 3 which
directs the charge wholly or partially through intercoolers 13 and
14, or directly to manifolds 13 and 14 which distributes the
temperature-adjusted charge-air to cylinder 7 inlet valves 16 and
16' to each power cylinder of the engine. An off-and-on control
valve (not shown) and conduit 32' directs air to air box 51 and to
scavenging ports 52a-52f in the bottom of cylinders 7a-7f. In the
alternates embodiment (shown in phantom in FIG. 25), the scavenging
air is directed through pressure reduction valve 25, arranged on
conduit 50 to provide and adjust scavenging air pressure from
compression 1. Another option to reducing the manifold air pressure
for scavenging the cylinders 7a-7f is to use the manifold air
through conduit 50, air box 51 and intake ports 52a-52f without
reducing the pressure from manifolds 13 and 14. The air would be
used at full pressure for scavenging by the scavenging ports
52a-52f in FIG. 25 and through inlet port 52'' and exhaust port 52'
in FIG. 30, which ports 52a-52f, 52' and 52'' would be constructed
much smaller than normally done. In this instance, although the
scavenging ports were smaller-than-normal, the higher-than-normal
pressure scavenging air would be very efficient. Several means of
scavenging the cylinders are suggested herein. FIG. 26 illustrates
more clearly (although in phantom) the preferred system of
supplying low pressure scavenging air. Conduit 32' and valve 33
(shown in phantom in FIG. 26) channels air from conduit 110 from
compressor 2 to conduit 50 which supplies scavenging air to air box
51.
[0283] The engine control module (ECM) 27 (see, for example, FIG.
26) controls valves 3, 4, 5, and 6 in order to adjust the pressure,
temperature and density of the charge going to the combustion
chambers and valve 25, and can selectively direct a portion, a
portion at a reduced pressure of the air charge to scavenging ports
52 and can control valve 53 and valves 49' to open or close to
select the mode of scavenging desired. The ECM can also control a
variable-valve-happening control system to adjust the valve opening
time and duration of opening time of inlet valves 16 and exhaust
valves 17 in relationship to the degree or angle of rotation of
crankshaft 20, in order to adjust the compression ratio of the
engine for optimum performance in regard to power, torque, fuel
economy, fuel characteristics and to scavenging mode desired.
The Preferred Operation of the Power Cylinders Shown in FIG. 25 is
in this Manner:
[0284] After blowdown and scavenging of the cylinder 7 has taken
place the cylinder is now filled with fresh air, and piston 22 has
closed exhaust ports 52 and the piston 22 is in its
scavenging-charging stroke and is rising with the exhaust valve 17
still open, at any point, perhaps as early as 120 to 90 degrees
before top dead center, the exhaust valve 17 is closed to establish
the compression ratio and begin compression, intake valve 16, 16'
are opened at that time or later in order to produce the desired
charge density and weight desired, the compressed air charge or
fuel air mixture is injected through intake valve 16, 16', intake
valve 16, 16' is then closed. Compression of the charge which
started at point X, the point where exhaust valve 17 was closed,
continues with the compression ratio being established by the
cylinder clearance volume remaining at point x, divided by the
combustion chamber volume. Fuel can be injected into the secondary
compressed air stream being injected into the combustion chamber or
injected into a pre-combustion chamber (one is shown in FIG. 21) or
may be injected directly into the combustion chamber. After the
closure of intake valve 16, 16', the fuel or more fuel can be
injected into the midst of the charge swirl for a stratified charge
combustion process, or as in compression ignited engines fuel can
be injected directly into the combustion chamber, perhaps directly
onto a glow plug, if suggested pre-combustion chamber is used or
not, and can be injected continuously during part of the expansion
stroke for a mostly constant pressure combustion process.
[0285] The fuel-air mixture is ignited by spark plug, by
compression ignition, or by glow plug at the point deemed most
efficient, preferably before top dead center of the compression
stroke of piston 22. The expansion stroke of piston 22 takes place
as the expanding gases force the piston toward bottom dead center.
Near the end of the power stroke, perhaps about 40.degree. before
bottom dead center, scavenging ports 52 are uncovered, near the
same time exhaust valve(s) 17 in the engine head are opened and a
rapid blowdown and scavenging takes place in any of four ways as
shown in FIG. 27, FIG. 28, FIG. 29 and FIG. 30. In any case the
exhaust valves 17, 17' remain open past bottom dead center and for
a significant part of the scavenging-charge-adjusting stroke in
order to establish the engines compression ratio.
[0286] Referring now to FIG. 26, there is shown a schematic drawing
showing an engine similar in structure and operation to the engine
100.sup.25 of FIG. 25, having two compressors, but differing in
that compressor 1 is depicted as a Lysholm rotary compressor, and
compressor 2 is depicted as a turbo compressor, and having one air
cooler for the secondary compressor, two air coolers for the
primary compressor, dual manifolds, with shutter controls, air
bypass controls and conduits for different air paths. Also shown is
an engine control module (ECM) 27 which can control charge and
scavenging air pressures, density and temperatures in order to
effect the desired output and emissions characteristics of the
engine. Alternate sources of scavenging air are shown, the
preferred one being from conduit 110 by way of conduit 32'. Air
paths are shown by arrows, hollow arrows for uncooled compressed
air and solid arrows for cooled denser air. Also shown are air
bypass valves (in this case both closed) which, with the shutter
valves (one of which is closed and one of which is partly open, the
latter to allow cooling of part of the charge), can control the
charge temperature, weight and density as required for best engine
performance.
[0287] Referring now to FIG. 27, there is shown one system of
efficient scavenging of the exhausted products of the engine of
FIG. 25;
Scavenging System A (FIG. 27)
[0288] Blowdown of exhaust occurs at from about 40.degree. before
bottom dead center to perhaps 40-50.degree. after bottom dead
center, with exhaust valves 17 opening at approximately the same
time the ports 52 are opened and remaining open after bottom ports
are closed by piston 22, and closing later causing a low
compression ratio.
[0289] Scavenging air can be supplied from a manifold with perhaps
a pressure-reducing valve 25 on conduit 50 or, preferably
scavenging air can be supplied from conduit 32' from ancillary
compressor 2, (shown in phantom). In this case, bottom ports 52
open shortly before exhaust valves 17 open. Blowdown occurs through
bottom ports 52 out through bottom exhaust conduit and valve 53 to
main exhaust pipe 18, at same time or shortly after, exhaust valves
17 open and blowdown of the exhaust occurs both at the top of the
cylinder through exhaust valves 53 and 17, and through exhaust
manifold 18' and pipe 18 to the atmosphere. The exhaust valve 17
then stays open through a significant part of the 2nd or
exhaust-charge stroke for additional scavenging, this part by
positive displacement. During this scavenging-charging stroke the
exhaust valve 17 may be closed at any point after the first 20
percent of piston 22 travel. Now at any point with cylinder 7 being
now filled with fresh air, exhaust valve 17 can close and intake
valve 16' open to admit pressurized air which has its temperature
adjusted to what is deemed proper. The later in the
exhaust-charging stroke the exhaust valve 17 is closed, the lower
is the compression ratio of the engine established. If closed early
enough the effective compression ratio can be as much as 13 or 16
to 1, if closed later the effective compression ratio can be as low
as 2:1. At any point after exhaust valve 17 has closed, and the
compression ratio has been established, and before piston 22 has
reached top dead center, the air charge, with temperature density
and pressure adjusted may be introduced by opening and then closing
intake valve 16. All of the operating parameters suggested would
depend on the duty cycle of the engines, e.g., power requirements,
efficiency, emissions considerations and the fuel used.
[0290] An engine control module (ECM) 27 is shown with connections
to the critical control valves of the engine which can be adjusted
according the conditions signaled to the ECM 27 from various
sensors in the engine.
[0291] Referring now to FIG. 28, there is shown a second system of
efficiently scavenging the engine of FIG. 25;
Scavenging System B (FIG. 28)
[0292] Exhaust blowdown occurs through exhaust valves 17 only, with
scavenging air being supplied by compressor 2 by way of conduit
32', or alternatively from manifolds 13 and 14 through conduits 50
past control valve 49 and optional pressure control 25 into air box
51 and through scavenging ports 52 in the bottom of the cylinders
7, up through the cylinder 7, out exhaust valves 17 and through
exhaust pipe 18, with valve 53 being closed. In this system as
piston 22 approaches bottom dead center in the power expansion
stroke, ports 52 would be uncovered by piston 22 and as blowdown
occurs pressurized air would be injected through all bottom ports
52 and would sweep combusted products through exhaust valves 17
which open perhaps before ports 52 for the exhaust blowdown. The
bottom ports can be constructed to open at perhaps 40.degree.
before bottom dead center and could close at the same point after
piston begins its second stroke. The exhaust valves 17 could remain
open after bottom ports 52 are closed to aid in scavenging by
positive displacement by piston 22 and to establish the desired
compression ratio which is established by the point at which
exhaust valves 17 close.
[0293] During this scavenging-charging stroke of piston 22 the
cylinder 7 being now filled with fresh air, the exhaust valve 17
may be closed at any point after the first 20 percent or so of
piston 22 travel. Now at any point exhaust valve 17 can close and
intake valve 16 can open to admit highly pressurized air which has
its temperature and density adjusted to what is deemed proper. The
later in the exhaust-charging stroke the exhaust valve 17 is
closed, the lower is the effective compression ratio of the engine
established. If closed early enough the effective compression ratio
can be as much as 13 or 19 to 1, if closed later the effective
compression ratio can be as low as 2:1. All of the operating
parameters suggested would depend on the duty cycle of the engines,
e.g., power requirements, efficiency and emissions considerations
and the fuel used.
[0294] An engine control module 27 is suggested for use as shown
for controlling the various operating conditions desired and as
signaled from the engine's various sensors.
[0295] Referring now to FIG. 29, there is shown a third efficient
system of scavenging the engine of FIG. 25;
Scavenging System C (FIG. 29)
[0296] This scavenging system would be that shut off valves 49'
would be closed, (or valves 25 and 49 could be eliminated), with
bottom ports opened to the atmosphere by valve 53, one inlet valve
16 leading from manifolds 13 and 14 to cylinder 7 could be opened
for a very short period of time by a cam, perhaps by a small lobe
on a cam that has a large lobe to open the same valve (as 21-C in
FIG. 11) at a different crank angle, at the same time ports 52 were
uncovered by piston 22 and exhaust valves 17 were opened. The high
pressure air would quickly sweep combusted gases through ports 52
and exhaust valves 17, through their respective exhaust pipes 17
and 17' to the atmosphere. The intake valve 16 would close quickly,
no later than the time exhaust ports 52 closed. The exhaust valve
would remain open for further scavenging and for the reduction of
the compression ratio of the engine. Alternatively bottom exhaust
valves 53 would be closed and as bottom ports 52 were uncovered by
piston 22, exhaust valves 17 would also open earlier for blowdown,
air from the airbox 51 supplied by conduit 32 would blow into ports
52 and scavenge the cylinder 7 through exhaust valves 17.
[0297] During this scavenging-charging stroke the exhaust valve 17
is closed at a point after the first 20 percent or so of piston 22
travel. At any point after exhaust valve 17 has closed, the
cylinder 7 being now filled with fresh air, and the compression
ratio having been established, and before piston 22 has reached top
dead center, additional (secondary) air charge, with temperature
density and pressure adjusted is introduced when needed by opening
a second intake valve 16 and/or by another lobe 21-C on the same
cam (see 21-C, FIG. 11) opening the same intake valve again. All of
the operating parameters suggested would depend on the duty cycle
of the engines, e.g., power requirements, efficiency and emissions
considerations and the fuel used. The later in the exhaust-charging
stroke the exhaust valve 17 is closed, the lower is the compression
ratio of the engine established. If closed early enough the
effective compression ratio can be as much as 13:1 or 22:1, if
closed later the effective compression ratio can be as low as
2:1.
[0298] An engine control module could control all of the conditions
required of the engine.
[0299] Referring now to FIG. 30, there is shown a fourth system of
efficient scavenging the engine of FIG. 25.
Scavenging System D (FIG. 30)
[0300] In this system exhaust blowdown occurs through the top
exhaust valves 17 and through part of the bottom scavenging ports
52' which open just before bottom dead center, perhaps 40.degree.,
and simultaneously with or just after the top exhaust valves open.
At the time bottom ports 52' are opened, or shortly after, exhaust
valves 17 are also opened, or, valve 53 leading to bottom exhaust
line 18 is already open, and exhaust blowdown occurs over the next,
40.degree. or so after bottom dead center, with scavenging air
being injected through at least one of the bottom ports 52'' which
has been constructed to receive pressurized air from air box 55
supplied by conduit 32' or 50 at such a time the ports 52' are
opened by piston 22 and the pressure in cylinder 7 has dropped
below the pressure in air-box 55. After ports 52' are closed,
exhaust valves remain open through a significant part of the second
or exhaust-charge stroke of piston 22 for additional scavenging by
positive displacement and in order to establish a low compression
ratio.
[0301] During this scavenging-charging stroke the cylinder 7 being
now filled with fresh air, exhaust valve 17 may be closed at any
point after the first 20 percent or so of piston 22 travel. Now at
any point exhaust valve 17 can close to establish the compression
ratio and inlet valve 16 can open to admit a secondary pressurized
air charge which has its temperature and pressure adjusted to what
is deemed proper. The later in the exhaust-charging stroke the
exhaust valve 17 is closed, the lower is the compression ratio of
the engine established. If closed early enough the effective
compression ratio can be as much as 13:1 or 22:1, if closed later
the effective compression ratio can be as low as 2:1. All of the
operating parameters suggested would depend on the duty cycle of
the engines, e.g., power requirements, efficiency and emissions
considerations and the type of fuel used, and can be controlled by
an engine control module which receives signals relating conditions
in certain engine areas and which are relayed to the ECM 27.
[0302] Referring to FIG. 31, there is shown a schematic drawing
depicting an alternate arrangement in which an electric motor 34
preferably drives the air compressors of an engine similar to that
of FIG. 25.
[0303] Referring now to FIG. 32, there is shown a schematic drawing
showing the 2-stroke engine of FIG. 25 and FIG. 26 and having only
one compressor 1 for supplying both scavenging and charge-air. Also
shown are a shutter valve 3 and an air bypass valve 4, valves 16
and 17 controlling charge and scavenging air and valves 53 and 53'
for releasing exhaust blowdown out of the cylinder bottom ports 52
through exhaust conduit 18 to the atmosphere. Thus the engine of
FIG. 32 can perform all of the feats described for the engine of
FIG. 25 and described for the engine of FIG. 25, FIG. 26, FIG. 27,
FIG. 28, FIG. 29, FIG. 30 and FIG. 32. Also shown is an engine
control module (ECM) 27, and connections to various valves in order
to manage the charge and scavenging air temperature, density,
weight and pressure, and the pressure and path of the scavenging
air to achieve the desired results from the engine. Arrows show the
paths possible for the heated (hollow arrows) air and the cooled
(solid arrows), air, and for the charge-air to pass through the air
bypass valve 4, all in order to adjust air pressure, density,
weight and temperature for optimum engine performance.
The Engine 100.sup.33 System of FIG. 33
[0304] Referring now to FIG. 33, there is illustrated a six
cylinder internal combustion engine in which part of the cylinders
62 through 65 are used for producing power and two of the
cylinders, cylinders 66 and 67, are used for compressing the air
necessary to operate the engine. A supercharger 57, in this case
preferably a Lysholm type, is used to boost the atmospheric
pressure air received through air intake 8', before the air enters
compressor cylinders 66 and 67. A shutter valve 3' and air bypass
valve 4' re-circulate the charge-air back through compressor 57
when both are opens to lessen compressor work and reduce charge
densities for light-load operation. When air bypass valve 4' is
closed shutter valve 3' can open or close to send the air charge to
the cylinders cooled or uncooled, respectively, in order to manage
combustion temperatures and temperatures for optimum
performance.
[0305] The second stage of compression is transferred from
compression cylinders 66 and 67 through conduits 201, 202 to
shutter valve 4'' which, when closed, sends the compressed charge
through conduit 204 and intercooler 11 and conduit 205 to the
engine manifold 58' in a cooled condition. If opened, shutter valve
4'' directs the charge away from cooler 11 through conduit 203 and
205 to the power cylinders without cooling.
[0306] By having its camshaft arranged to rotate at one-half
crankshaft speed, the engine 100.sup.33 operates in a 4-stroke
cycle, with a low compression ratio, an extended expansion ratio
and high mean effective cylinder pressure when operated in a manner
just as described herein for the engine of FIG. 3.
[0307] Alternatively, the engine of FIG. 33, with one or more of
its cylinders acting as compressor cylinders and having its
camshaft arranged to rotate at crankshaft speed, operates in a
2-stroke cycle with the low compression ratio, high mean effective
cylinder pressure and an extended expansion ratio when operated in
the manner described herein for the engines of FIG. 8, FIG. 9 and
FIG. 11.
[0308] Still referring to FIG. 33 of the drawings, additional fuel
savings can be achieved in any of the engines of the present
invention described hereinbefore by use of an economizer
constructed as an air compressor retarder brake. For discussion of
the disclosed retarder brake, this six-cylinder engine 100.sup.33
represents any of the engines of this invention which use
externally compressed air (FIG. 1 through FIG. 33) to either fully
supply charge-air or which use it to enhance engine performance.
The air retarder brake illustrated has a compressor 57A operatively
connected to the drive shaft of the vehicle (not shown) or geared
to the engines crankshaft 20 and stores energy produced during
braking or downhill travel which is utilized to supply compressed
air to the engine power cylinders via the transfer manifold 58.
Such an economizer is coupled with an air reservoir 59 and during
the time in which the economizer reservoir air pressure was
sufficiently high for use in the power cylinders of the engine, the
engine compressor can be clutchably disengaged or air pumped by the
compressor(s) can be bypassed back to the inlet of the
compressor(s) so that no compression work would be required of the
compressor. A relief valve 60 prevents excess build up of pressure
in the air reservoir. A valve 61 (being in this arrangement, a
reversible one-way valve) allows air from the reservoir to be
transferred to the manifold when the pressure in the reservoir 59
is higher than in the transfer manifold 58, if the air is needed.
In the case of engine constructions having compression cylinders,
each compression cylinder of the engine can also be deactivated
during this reserve air operation time by shutting off the
admission valve so that no net work would be done by the
compressor(s) until the manifold-reservoir pressure dropped below
operating levels. Several systems of deactivating cylinder valves
are described in the art and/or have been mentioned previously.
[0309] In an alternate arrangement, the compressor 57A is
eliminated and the air storage tank 59 is used to store excess air
compressed by the compressor cylinders of the engine during braking
and downhill travel. In this case, the valve 61 is a two-way valve
and a blocking valve 70 is placed in the manifold 58 between the
compressor cylinder(s) 66, 67 and the working cylinders 62-65.
During downhill travel or during braking, the blocking valve 70
between compressor and working cylinders is, preferably, closed,
power cylinders 62-65 are deactivated, and the two-way valve at 61
is utilized in order to divert the air compressed by the compressor
cylinder(s) into storage tank 59.
[0310] When it is desired to operate the engine normally, the
blocking valve 70 between the compressor and the expander cylinders
is opened and the two-way valve 61 is closed. During reserve air
operation, both the blocking valve 70 and the two-way valve 61 are
opened. If desired, the compressor cylinder(s) 66, 67 are
deactivated while in the reserve air operation mode, as described
earlier. Also, a Jacob brake (a prior art retarder brake) could
supply compressed air to the air reservoir tank.
[0311] Operating the engine on reserve air supply would improve the
mean effective pressure (mep) of the engine for 20 percent
improvement in power and efficiency, while reducing polluting
emissions, during the time the engine was operating on the reserve
air.
[0312] This feature would produce additional savings in energy
especially in heavy traffic or in hilly country. For example, an
engine producing 100 horsepower uses 12.7 pounds of air per minute.
Therefore, if energy of braking were stored in the compressed air
in the economizer reservoir 59, a ten or fifteen minute supply of
compressed air can be accumulated and stored during stops and down
hill travel. When the reservoir pressure drops below the desired
level for efficient operation, a solenoid (not shown) is used to
reactivate the compression cylinder valves and they (with the
supercharger, when needed) will begin to compress the air charge
needed by the engine.
[0313] Using the air reservoir 59, the engine needs no compression
build-up for starting and as soon as the shaft was rotated far
enough to open the intake valve, the compressed air and fuel would
enter and be ignited for "instant" starting. Furthermore, the
compressed air could be used to rotate the engine for this means of
starting by opening intake valves earlier than usual to the
expander cylinders to begin rotation and firing as is common in
large diesel engines, thus eliminating the need for a starter
motor. Alternatively, the compressed air could be used to charge a
"hydrostarter" to crank the engine as is common on some heavy-duty
diesel engines.
[0314] In an alternate, and still preferred embodiment, the reserve
air in reservoir 59 is additionally used to "motor" the engine to
allow a vehicle such as a bus to pull away from a stop and operate
fuelless for 30-60 seconds or more, which is the time that greatest
pollution occurs in bus or stop-and-go delivery vehicle
operation.
Remotely Compressed Air Embodiments
[0315] Referring now to FIG. 34, there is seen a schematic
representation of an engine 100 in accordance with an alternate
embodiment of the present invention for externally providing
charge-air for marine, locomotive, stationary, or electric power
generating engines, or any engine applications of this invention,
constant or variable load and speed, which have adequate electric
power or waste or "bleed" air available. In FIG. 34, a remote
electric air compressor 35 preferably with one or more intercooled
compression stages, preferably supplies temperature conditioned
charge-air (both high and low pressure, if needed) for one or more
engines of this invention. The charge-air, conditioned in
temperature and pressure, is supplied directly to manifolds 13 and
14 by conduit 15AE from compressor 35. The engine intake conduit 9
of, for example, FIG. 4, or low-pressure conduits 32 of other
engines of this invention receive air from the atmosphere or
alternatively receives low pressure air from a low pressure conduit
15BE from compressor 35.
[0316] An alternate arrangement, also depicted in FIG. 34, for
providing combustion charge-air for any of the engines 100 of the
present invention is to provide charge-air from conduit 15AR which
supplies waste or "bleed" air produced in industrial processes. The
air is supplied either at 1 or 2 pressure levels. The lower
pressure, if needed, preferably is supplied by dropping the
pressure from the main incoming waste air conduit 15AR with a
pressure regulator valve (25a leading to low-pressure conduit
15BR). The arrangement is similar to the arrangement of conduits
15-A, 15-B and valve 25 in, for example, FIG. 5, with conduit 15-A
representing the supply conduit 15AR from the waste air supply, and
with conduit 15-B representing conduit 15BR in FIG. 34.
[0317] The use of remotely compressed air, either waste air or from
compressor 35, eliminates the engines compressors 1, 2 intercoolers
10, 11, 12, certain conduits and valves 3, 4, 5, 6 of the
charge-air supply equipment, providing the air has been conditioned
during or after the compression process (and prior to introduction
to the manifolds 13, 14). Thus, the equipment of the engine 100 of
the various embodiments shown throughout the various drawing
figures of the engine 100 embodiments of this invention, is
preferably eliminated up to those points designated by dashed lines
A, B and C throughout the various drawings. The charge-air from
either of the aforementioned remote sources is preferably
introduced into the engines near the manifolds 13 and 14 and, in
the appropriate embodiments, the low air pressure from the remote
sources is introduced at conduit 32, as shown in FIG. 34.
[0318] In the remotely charged engines, the fuel can be carbureted
prior to compression, can be throttle-body injected, port-injected,
or directly cylinder injected.
Regarding Pollution Control
[0319] Referring now to FIG. 2 and FIG. 4-C there is shown a method
of further reducing polluting emissions in any of the engine
embodiments of this invention which includes re-burning a portion
of the exhausted gases when and if required. In the 4-stroke
engines of FIG. 1-FIG. 3 and in the 2-stroke engines herein
depicted having a single air intake, the exhaust outlet conduit(s)
18 have a shunt conduit 202 (refer to FIG. 2) leading from a port
206 in the side of exhaust conduit 18 to a port 204 in the side of
intake conduit 8. A proportioning valve 201 is situated at the
intake port 204 and is arranged to selectively restrict the flow of
fresh air into conduit 8, while at the same time opening the port
204 to the exhaust conduit to selectively allow entry of exhaust
gases to the intake conduit 8. This valve is variable and
mechanically, electrically or vacuum solenoid operated and
preferably controlled by an engine control module (ECM) or control
144 in FIG. 35 and FIG. 36. This allows the re-burning of a portion
of the exhausted gases, the amount of percentages thereof being
adjusted by the engine control module in response to various
sensors, such as an oxygen sensor, placed in strategic positions in
the engine. Exhausted gases passing through conduit 202 can be
cooled by either optional cooling fins 202a or by passing through
an optional intercooler (not shown) before reaching the air intake
conduit 8.
[0320] With reference to FIG. 4C, in engines having only one
atmospheric intake conduit but having different air paths and
conduits, such as conduits 15-A and 15-C of FIG. 4B, a shunt
conduit 202' leading from the exhaust conduit 18 is divided into
two shunt conduit portions 203a, 203b, each with a proportioning
valve 209a, 209b operating so as to selectively admit exhausted
gases to either or both of intake valve 16-B (through conduit 9 and
eventually conduit 15-C) or to intake valve 16-A (by way of conduit
8 and conduit 15-A). Each proportioning valve 209a, 209b would
allow either a portion or none of the exhausted gases to enter its
respective port, meanwhile restricting entrance of fresh air if
necessary. The exhausted gases can be cooled by optionally
arranging fins 202a on conduit 202' and/or 203a, 203b and 203c or
by passing the exhaust through an optional intercooler (not shown)
before the gases are introduced into the air intake(s) of the
engine.
[0321] Alternatively, as shown in phantom on FIG. 4C, one shunt
portion 203a is diverted (shown as 203c) directly to conduit 15-C
and provided there with a proportioning valve 209c.
[0322] In the engines of FIG. 4 and FIG. 7 having dual atmospheric
air intakes 8, 9, an arrangement similar to that shown in FIG. 4C
is utilized, it being understood, however, that conduit 8 is open
to the atmosphere.
[0323] In any engines having dual air intake conduits or dual air
paths a portion of exhausted gases can be introduced in any amount
necessary, in from one to three points and controlled preferably by
an engine control module (ECM) for better management of combustion
and emissions characteristics.
[0324] This re-burn feature is of particular importance with diesel
fuel operation.
Constant Load and Speed Engines
[0325] Whereas the preponderance of the foregoing specification
describes embodiments and representative engines of the present
invention which are optimized for vehicular (marine, truck, bus,
automobile, tank, train and plane) duty cycles and describe systems
and methods for varying power, torque and speed, the present
invention finds useful application for obtaining high power and
torque while maintaining optimum fuel economy and low polluting
emissions in less complex engines, such as, for example, constant
load and speed engines. FIG. 35 and FIG. 36 depict alternate
embodiments of the present invention which embodiments are
representative of constant load and speed engines (e.g., for
electric power generation and in other stationary or industrial
engine applications, e.g., for pumps and compressors) outfitted in
accordance with the principles of the present invention.
[0326] The Engine of 100 System of FIG. 35
[0327] Referring now to FIG. 35 there is shown is a schematic
presentation of an engine which represents any of the 4-stroke or
2-stroke engines of the present invention outfitted for constant
load and speed operation. The basic components of the engine 100,
such as compressors 1, 2 and optional intercoolers 10, 11, 12
(shown in phantom) and their necessary associated conduits are,
preferably, designed for optimum operating parameters having only
the basic components. The various controls, shutter valves, air
bypass valves and their associated bypass conduits such as those in
previously described embodiments, are preferably eliminated in
order to reduce weight, cost and complexity of operation. In FIG.
35, the engine 100 is shown as outfitted with a first ancillary
compressor 1 and a second ancillary compressor 2, optional
intercoolers 10, 11, 12 (shown in phantom) and interconnecting
conduits, all operating as would be understood with reference to
the previous detailed descriptions and operating with two stages of
pre-compression of the charge-air, intercooled or adiabatically
compressed.
[0328] FIG. 35 shows a preferred setup for power generation with
any of the engines of this invention. The power output shaft 20 of
the engine 100 is coupled schematically by line 140 to power input
shaft 20'' of generator 141 which has electric power output lines
142. As the shaft 20 of the engine 100 rotates the shaft 20'' of
generator 141, the amount of electric power produced by generator
141 is detected by sensor 143 and relayed to control unit and
governor 144 which contains various relays and integrated circuits
to quantify the power output and to send messages by line 145 to
fuel/air control (not shown) on fuel line 148 and throttle 56,
and/or by line 149 to spark control to advance or retard the spark
in spark-ignited engines and/or to send messages through lines 146
and 146b for engines having fuel injection systems, e.g. for
natural gas, gasoline or diesel fuel, or to fuel/air controls, all
in order to control the fuel input, speed and output of engine 100
and hence the output of generator 141. Control unit 144 also sends
signals to control the proportioning valve 201, shown in FIG. 4 and
to proportioning valves 209a, 209b, 209c shown in FIG. 2 to control
the amount, if any, of exhaust recirculated by these valves for
re-burn in any engine of this invention utilizing this feature.
Further explanation of the components and operation with the engine
100 of the present invention is deemed unnecessary as it would be
understood by those skilled in the art having reference to the
present disclosure.
[0329] The optional intercoolers 10, 11, 12 (shown in phantom) are
preferably used for gaseous or gasoline fueled engines and are
preferably eliminated or reduced in number or cooling capacity in
the compression-ignited engine, this being made possible by low
peak pressures and temperatures in the engines of this
invention.
[0330] Referring now to FIG. 36 there is shown an engine
illustrated as a 2-stroke engine but representing any of the
engines of the present invention, 2-stroke or 4-stroke, which is
coupled schematically by line 140 with an electric generator 141.
The engine and arrangements are similar in structure and operation
as that shown and described for the engine of FIG. 35 with the
exception that engine of FIG. 36, operating as either 2-stroke or
4-stroke cycle engine 100, has only a single stage of
pre-compression, optionally intercooled by intercoolers 11, 12
(shown in phantom), of the charge air. As with the engine of FIG.
35, intercoolers 11, 12 are preferably eliminated or reduced in
cooling capacity in compression-ignited versions of the engine 100
of this invention. Also, as with the engine 100 of FIG. 35, the
governor, and other controls and the operation of the engine and
generator would be understood by those skilled in the art having
reference to the present disclosure.
[0331] It will be seen by the foregoing description of a plurality
of embodiments of the present invention, that the advantages sought
from the present invention are common to all embodiments.
[0332] While there have been herein described approved embodiments
of this invention, it will be understood that many and various
changes and modifications in form, arrangement of parts and details
of construction thereof may be made without departing from the
spirit of the invention and that all such changes and modifications
as fall within the scope of the appended claims are contemplated as
a part of this invention.
[0333] While the embodiments of the present invention which have
been disclosed herein are the preferred forms, other embodiments of
the present invention will suggest themselves to persons skilled in
the art in view of this disclosure. Therefore, it will be
understood that variations and modifications can be effected within
the spirit and scope of the invention and that the scope of the
present invention should only be limited by the claims below.
Furthermore, the equivalents of all means-or-step-plus-function
elements in the claims below are intended to include any structure,
material, or acts for performing the function as specifically
claimed and as would be understood by persons skilled in the art of
this disclosure, without suggesting that any of the structure,
material, or acts are more obvious by virtue of their association
with other elements.
* * * * *