U.S. patent application number 11/650074 was filed with the patent office on 2007-05-24 for air-hybrid and utility engine.
Invention is credited to Walt Froloff, Kenneth C. Miller.
Application Number | 20070113803 11/650074 |
Document ID | / |
Family ID | 34838584 |
Filed Date | 2007-05-24 |
United States Patent
Application |
20070113803 |
Kind Code |
A1 |
Froloff; Walt ; et
al. |
May 24, 2007 |
Air-hybrid and utility engine
Abstract
A dynamically re-configurable multi-stroke internal combustion
engine, comprised of programmable computer processor controlled
engine components for decoupling the four classic strokes of an
internal combustion engine and electronically managing engine
cylinder components including such cylinder components as
electronically controllable valves, fuel injection and air fuel
mixture ignition, allowing additional engine cylinder unit
component states and thus cylinder strokes to be independently
altered or re-sequenced by computer control to provide alternate
engine modes of operation. Some alternate engine modes are
facilitated by addition of a compressed air storage reservoir to
receive cylinder generated compressed air or transfer compressed
air to cylinder units in other modes to increase engine power,
efficiency or utility. Sensor input and on-demand requirements
drive control logic to manage engine strokes through control of
individual cylinder component states. Dynamic reconfiguration of
individual component states provides re-generative engine energy
modes, boost power modes, and mixed modes which use compressed air
stored energy re-introduced for alternate cylinder state sequences
and alternate engine modes of operation which add utility and
efficiency to otherwise fixed sequence multi-stroke power
generation in internal combustion engines.
Inventors: |
Froloff; Walt; (Aptos,
CA) ; Miller; Kenneth C.; (Aptos, CA) |
Correspondence
Address: |
Walt FROLOFF
273D Searidige Rd
Aptos
CA
95003
US
|
Family ID: |
34838584 |
Appl. No.: |
11/650074 |
Filed: |
January 5, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10780410 |
Feb 17, 2004 |
7050900 |
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11650074 |
Jan 5, 2007 |
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11257800 |
Oct 25, 2005 |
7177751 |
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11650074 |
Jan 5, 2007 |
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Current U.S.
Class: |
123/90.11 ;
123/21; 123/316; 701/103 |
Current CPC
Class: |
F02B 2075/125 20130101;
F02D 13/04 20130101; F02B 75/02 20130101; F02B 2075/025 20130101;
F02D 41/0087 20130101; Y02T 10/40 20130101; F02B 2075/027 20130101;
F02B 21/00 20130101; F02B 69/06 20130101; F02D 37/02 20130101; F01L
1/46 20130101; F01L 9/20 20210101; Y02T 10/12 20130101 |
Class at
Publication: |
123/090.11 ;
701/103; 123/316; 123/021 |
International
Class: |
G05D 1/00 20060101
G05D001/00; F02B 69/06 20060101 F02B069/06; F01L 9/04 20060101
F01L009/04; F02B 75/02 20060101 F02B075/02; G06F 17/00 20060101
G06F017/00 |
Claims
1. A dynamically re-configurable internal combustion engine coupled
to operation of a vehicle comprising: one or more cylinder units
each with expanding and contracting cylinder volume and associated
stroke sequences; each cylinder unit having an intake port and an
electronically controllable intake valve component having multiple
states under computer control; each cylinder unit having an exhaust
port and an electronically controllable exhaust valve component
having multiple states under computer control; each cylinder unit
having an electronic fuel injector component having multiple states
under computer control; each cylinder unit having an air-fuel
mixture ignition means for igniting an air-fuel mixture in the
cylinder volume, said ignition means under computer control; each
cylinder unit having a switch for selecting a first stroke sequence
for combusting a compressed air-fuel mixture for a power stroke and
for selecting a second stroke sequence for expelling compressed air
for alternate use, said switching means under computer control; a
compressed air storage reservoir charged by one or more cylinder
units having an associated valve component for flowing compressed
air from a cylinder unit to the compressed air storage and
associated valve components having multiple states under computer
control for metering compressed air from the compressed air storage
into cylinder unit; a computer usable medium; and a computer
control system comprising computer readable program logic embodied
in the computer usable medium for controlling the steps of
selecting component states to provide alterable cylinder unit
stroke sequences.
2. A dynamically re-configurable internal combustion engine as in
claim 1 further comprising a compressed air port and corresponding
electronically controllable valve for compressed air flow
control.
3. A dynamically re-configurable internal combustion engine coupled
to operation of a vehicle comprising: one or more cylinder units
each with expanding and contracting cylinder volume and associated
stroke sequences; each cylinder unit having an intake port and an
electronically controllable intake valve component having multiple
states under computer control; each cylinder unit having an exhaust
port and an electronically controllable exhaust valve component
having multiple states under computer control; each cylinder unit
having an electronic fuel injector component having multiple states
under computer control; each cylinder unit having an air-fuel
mixture ignition means for igniting an air-fuel mixture in the
cylinder volume, said ignition means under computer control; each
cylinder unit having a switch for selecting a first stroke sequence
for drawing air into cylinder and for selecting a second stroke
sequence drawing a vacuum in cylinder, said switch under computer
control; a computer usable medium; and a computer control system
comprising computer readable program logic embodied in the computer
usable medium for controlling the steps of providing cylinder unit
stroke sequences for generating crankshaft power in the first
stroke sequence or vacuum for alternate use in the second stroke
sequence.
4. A method for controlling a dynamically re-configurable internal
combustion engine coupled to operation of a vehicle comprising:
determining if the vehicle engine is on, and if not, then selecting
Compression Start Mode if there is sufficient available source of
compressed air, and alternatively executing a battery engine start;
determining the vehicle power requirements from real-time vehicle
operating parameters and selecting engine Power Mode and
alternatively, Boost Power Mode if the magnitude of the vehicle
power requirement exceeds a given threshold and there is sufficient
available source of compressed air to provide the required engine
power; determining the vehicle braking requirements from real-time
vehicle operating parameters and selecting Re-Generative
Compression Braking Mode operation if there is available compressed
air storage capacity and alternatively, Compression Braking Mode,
to provide the required engine braking power; determining if the
vehicle is required to be in hot standby and selecting Compressed
Air Idle Mode if there is sufficient available source of compressed
air and alternatively, Power Mode, to provide engine hot standby;
and cycling through the above steps as there is need or until an
engine stop signal is received.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The field of the present invention relates in general to the
fields of internal combustion engines and alternate mechanical
utilities such as compressors, siphons, and air-engines. More
particularly, the field of the invention relates to a dynamically
reconfigurable multi-stroke computer programmable internal
combustion engine with selectable cylinder component states, stroke
sequences and changable cylinder firing order. The dynamically
reconfigurable nature of the engine facilitates additional modes of
operation that include compressed air production and storage,
compressed air boost power, air compression braking, compressed air
engine start, compressed air engine idle, suction and combinations
of these and other modes of operation.
[0003] 2. Background
[0004] The internal combustion engine has seen thousands of
improvements and developments. Some of the latest improvements
include fuel efficiency, pollution reduction, electronic ignition,
fuel mixture heating or cooling, fuel injection, variable
displacement, air-fuel mixing and digital controlling of
hydraulically actuated intake/exhaust valves. Camless hydraulically
driven intake and exhaust valves and electronically controlled
hydraulic fuel injectors are among the very latest innovations to
impact internal combustion engines.
[0005] A computer processor that provides commands to electronic
assemblies can finely control and vary valve actuation, fuel
injection and ignition. Electronic assemblies process commands and
feedback signals from these devices to manage engine operation.
Camless valve control allows engine control subsystems to vary
timing, lift, and compression ratio in response to engine load,
temperature, fuel/air mix, and other factors. The electronic
valve-control system improves performance while reducing
emissions.
[0006] There are several methods of camless valve control. Sturman,
U.S. Pat. No. 6,360,728 Control Module for controlling
hydraulically actuated intake/exhaust valves and fuel injection,
claim fast-acting electro-hydraulic actuators which provide
mechanical means for valve actuation under the control of an
electronic assembly. Solenoid actuated two-way spool valves can
also be actuated by digital pulses provided by an electronic
assembly. Camless technology brings the internal combustion engine
under even more electronic control potential and away from
inflexible mechanical controls.
[0007] There have been attempts to build engines that have variable
displacement, using maximum displacement for high load requirements
and switching to a lower displacement for lower power needs. These
methods for variable power requirements have been tried and so far
not met with great success.
[0008] Despite all the innovation, the internal combustion engine
mindset is still, in the vast majority, a basic four-stroke engine.
Thus, the past and current technologies are all focused on
operation efficiency and improvement of a basic four-stroke
internal combustion engine that operates strictly on the
intake-compression-power-exhaust cycle. The internal combustion
engine has four basic functions that correspond with each stroke;
suction, compression, power, and exhaust. Engines that can take
advantage of alternate stoke sequences and operation modes are
needed, which would produce higher economies of operation, lower
pollution emission, reduce add-on components and allow alternate
utility of applicable uses.
Camshaft Constraints
[0009] Engine camshafts are typically permanently synchronized with
the engine's crankshaft so that they operate the valves at a
specific point in each cycle. Efforts to work around camshaft
constraints have come in many forms, including variable-cam timing
mechanisms. Variable-cam timing allows the valves to be operated at
different points in the cycle, to provide performance that is
precisely tailored to the engine's specific speed and load at that
moment. If conditions require earlier valve opening and closing,
for example, to achieve more low speed torque, the control logic
commands solenoids to alter oil flow within the hydraulic cam
timing mechanism, which rotates the camshafts slightly. If the
valves should open later, to generate more high-speed power, the
mechanism retards the cams as needed. However, the cam timing is
moved forward or backward for all the cylinders on the cam-shaft,
solidifying the dependences and constraints between cylinders.
Furthermore, with limited exceptions, camshaft-using engines are
constrained to the classic four-stroke internal combustion engine
cycle.
[0010] Variable displacement engines are designed with cam-shafts
of slightly different forms to add the option to effectively reduce
or increase engine power by taking cylinders off and on power line
respectively to follow power requirements and minimize waste. What
are needed are ways to add more flexibility in internal combustion
engines such that independent control of valve states and stroke
sequences per cylinder unit can be achieved.
Turbochargers and Superchargers
[0011] Turbocharge and supercharge power boost systems for internal
combustion engines compress intake air by exhaust turbo boosters or
belt-driven blowers. They compress intake air to higher than
atmospheric air pressure to increase oxygen density in the fuel
mixture and thus increase fuel burn power. A turbocharger is an
engine add-on, which generally comprises a pair of turbines mounted
to a common shaft. One turbine is a drive turbine disposed in an
exhaust flow path, while the other turbine is a compressor turbine
disposed, conventionally into the intake flow path.
[0012] Turbochargers use engine exhaust gases discharged by the
combustion chambers moving across the exhaust turbine to rotate it
and the intake turbine thereby compressing gases in the fuel air
mixture. This compression permits an increase in the amount of air
introduced into each cylinder during the intake stroke of its
piston while maintaining a desired fuel/air ratio, to produce an
attendant increase in the engine's power output. Essentially, the
turbocharger converts exhaust mechanical energy into compressed
intake air with higher oxygen concentration.
[0013] Although these methods can increase an engine's power
output, turbochargers have many deficiencies. At some operating
points, turbochargers become unstable. A low RPM engine gives
little exhaust flow to drive the turbine and high vacuum manifold
conditions cause a reverse pressure differential in airflow through
the compressor side that applies rotational forces to the
compressor blade in opposition to the drive turbine. Thus, when
exhaust flow is relatively low, the airflow-produced forces may be
sufficient to cause reverse rotation of the compressor that renders
a turbocharger inoperative. Most turbochargers do not engage until
much higher than three thousand engine RPM for these reasons. In
addition, the turbocharger is load following in that power must
first be expended to produce exhaust that can advantageously turn
the compressor. Turbocharger power is low or non-existent at low
engine RPM and is ineffective in response to short stop-go engine
driving because of these deficiencies. Turbos are useful when extra
power is needed at high engine RPM. What is needed is a source of
compressed air, enriched in oxygen, for engine power requirements
that are not dependant on engine output but instead, independently
feed compressed air into engine cylinders on demand.
[0014] U.S. Pat. No. 6,141,965, Charge air systems for four-cycle
internal combustion engines, attempts to remedy some of the
turbocharger deficiencies by compressing air with a small electric
motor for engine RPM below 2500, a region where most turbochargers
are ineffective, then switching to essentially classical turbo
compression beyond 2500 RPM. This shows that there is a need for
compressed air at lower engine RPM but the cost currently is an
additional electric motor, complex conduit connections and an
additional complexity in the control system. What is needed is a
source of engine compressed air with settable engine speed
independent compressed air densities, with minimal high maintenance
add-on parts and unnecessary system complexity.
[0015] A supercharger develops high-density intake air by
separately compressing intake air with the use of a rapidly
spinning rotor that acts as a positive displacement air pump.
Although these provide large increases in power and torque, the
blowers drain energy from the engine crankshaft and generate high
crankshaft friction losses that result in poor fuel economy.
[0016] Turbo boosters and superchargers are separate engine
component add-ons that also add weight, unreliability and cost to
engines. What is needed are methods that do not add complex
components, maintenance costs or add disproportionately larger
costs to vehicle engines than the benefits that they provide. What
is needed are charged air sources which can provide extra boost
power on driver demand regardless of engine RPM.
Compression Braking
[0017] Vehicles typically use friction brakes that throw away
energy in the form of heat. Also, brake usage is not uniform. For a
fully loaded truck, a full stop from 60 mph might raise brake drum
temperatures to 600 degrees F. This is about the limit for safe
operation. If the brakes are not well maintained, or the load is
not distributed properly, then some brake drums might go to
800-1000 degrees F., which is dangerous. What is needed is a
braking system to augment a friction braking system to reduce risk
at peak brake use periods.
[0018] In order to compensate and reduce brake wear, drivers gear
down the vehicle transmission, increasing the engine RPM, thus
allowing the engine to perform work by suctioning air. Although
effective in deceleration, this method wastes valuable energy in
the form of suctioned air that cannot be used in power mode and
heating while spinning up lower gears. However, the currently
unchangeable four-stroke engine cycle prevents any further
practical use of this wasted energy.
[0019] Many large diesel trucks and some larger RVs are equipped
with "Jake Brakes," also known as compression release engine
braking systems. The basic idea behind a Jake Brake is to use the
engine to provide additional braking power. A Jake Brake turns the
engine into an air compressor to provide a great deal more braking
power. Compressing the air in the cylinder takes power when the
engine goes through a compression stroke.
[0020] A Jake Brake modifies the timing on the exhaust valves so
that, when braking is desired, the exhaust valves open as the
piston reaches the top of the compression stroke. The energy
gathered in the compressed air is released, so the compression
stroke actually provides engine braking power. The main advantage
of a Jake Brake is that it saves wear on the normal brakes. This is
especially important on long downhill stretches where brake shoes
and linings can heat up in excess of 800 degrees F. The lasting
disadvantage is that all of the compressed air that was used to
brake is thrown away. What is needed are ways to store and reuse
the compressed air thrown away in compression braking mode.
Intake Stroke
[0021] Much vehicle engine power is wasted in stop and go driving,
an unwanted consequence of road and traffic conditions. During some
of this time, drivers downshift transmissions to slow vehicles. If
downshifted to provide braking, engine drawing in of intake air is
used to slow the vehicle. Thus the intake stroke of the four-stroke
engine has a braking feature while producing vacuum. However, the
suction work produced by the engine is promptly thrown away. What
is needed are ways to harness that wasted suction power.
Re-Generative Braking
[0022] Some statistics indicate that 40% of engine power generated
is eventually lost through braking. What is needed are regenerative
braking systems which act to effectively brake a vehicle while
incorporating methods to store and recover braking energy. What is
needed are modes of engine operation that could produce, store and
accumulate energy for later use.
[0023] Typically, brakes expend much more energy and more quickly
than today's four-stroke engines can produce in terms of real-time
engine braking. Re-generative flywheel approaches include such
concepts as 4,171,029--Vehicle propulsion system with inertial
storage, but the applications are generally not economically
practical from added large costs and complexity above their utility
values. What is needed are engines that can substantially slow a
vehicle down without applying irreversible energy loss during
frictional braking. What is needed are practical and economic
methods of slowing a vehicle down by converting a vehicle's kinetic
energy reversibly into potential energy. This would result in the
capability of slowing a vehicle down, storing energy instead of
losing energy through irreversible processes, and re-using the
energy.
Vehicle Dependence on Battery
[0024] Most vehicles make heavy use of stored energy from a battery
to start the engine. Other stored energy methods can be used to
start an engine. Taking vehicle momentum, usually from an incline
advantage, and turning the engine over without a starter motor can
start most standard transmission vehicles. Along this fashion,
compressed air can function as an alternate source of stored
energy, which can, with the correct engine cycle configuration, be
used to turn the engine crankshaft to start the engine. An engine
with this capability would be more efficient due to the smaller
energy conversion losses currently encountered from converting
mechanical energy of the engine to electrical energy and back to
mechanical starter motor energy. Further more, at engine start, the
starting motor draws the largest single demand on the car battery
without which a smaller battery may suffice. An alternative method
of starting an internal combustion engine also adds reliability,
and therefore value.
Hybrid Vehicles
[0025] Due to demands for more efficient engines, today's vehicle
market is experiencing bifurcation from the typical four-stroke
internal combustion engine to hybrid engines. Hybrids use electric
motors and battery banks to improve fuel efficiency, adding power
during acceleration and reclaiming energy when braking and
coasting. Hybrid engines do not come without a price as the
electric motors and battery banks add weight and cost to the
vehicle, and generally reduce the size and therefore available
power the of engine. In fact, most hybrid auto manufactures are
still selling hybrids at a loss. What is needed are hybrid type
engines that do not add weight and the cost of large, heavy battery
banks, electrical generators and motors. Moreover, what is needed
are hybrids that do not force engines to be smaller and lower power
in order to be more efficient. Furthermore, what is also needed are
hybrids that do not have conversion losses from engine power to
electrical power and back from electrical power to mechanical
power. What is needed are hybrids that transfer mechanical engine
energy or vehicle momentum to recoverable energy forms which can be
quickly re-introduced for engine or external uses, thus further
extending the energy produced from combustion. While hybrids are a
good future option to increase energy efficiency, what is needed
are alternatives to the current single option, the
electric-combustion hybrid engine.
Hydrogen Powered Vehicles
[0026] Some auto industry experts proclaim hydrogen will be the
next fuel used to power vehicles and some car manufactures have
built model hydrogen fueled cars. These have come in two very
different technologies. One way is a hydrogen fuel cell electric
vehicle. The other method is to use hydrogen to fuel an internal
combustion engine. Here the hydrogen is combusted with oxygen to
generate power, hence turbo and super charging increases engine
power and idle engine strokes wastes fuel. Innovations to the
internal combustion engine will be directly applicable to hydrogen
fueled internal combustion engines of the future. A new Ford model
hydrogen fueled internal combustion engine is optimized to burn
hydrogen through the use of high-compression pistons, fuel
injectors designed specifically for hydrogen gas, a coil-on-plug
ignition system, an electronic throttle, and new engine management
software. This engine requires supercharging, which provides nearly
15 psi of boost on demand, but the engine is claimed to be up to 25
percent more fuel-efficient than a typical gasoline engine. Much
work is ongoing in this area and there is a continuing need to
improve internal combustion engine performance, increase engine
utility and efficiency while reducing engine waste and
pollution.
Air Powered Engines and Idle
[0027] Vehicle numbers and traffic increases have substantially
increased the time of even short distance travel. Furthermore,
internal combustion engines typically remain in idle mode while the
vehicle is waiting for stoplights, coasting, stalled in traffic,
etc. The idle mode is fuel wasteful as any power is only used for
keeping the engine crankshaft rotating so that flywheel rotation
energy is preserved. An incline, or available compressed air source
can serve the same function without use of more fuel. What is
needed are ways to keep the engine crankshaft rotating during idle
periods without additional fuel costs.
[0028] Currently, most engines use fixed mechanical cams to open
and close valves. Fixed mechanical cams enforce a rigid valve
opening and closing timing sequence regardless of external
conditions and circumstance. For this reason, when power is not
needed such as in low speed or halted traffic conditions, engine
power is wasted by cylinder strokes working to draw in, compress,
combust fuel and vent exhaust. This power is thrown out as a small
waste that is not cost effective to harvest. Based on the current
engine design, this is probably a good approach. What is needed are
methods to use those small individual quantities of engine-produced
compressed air that is otherwise discarded.
[0029] However impractical for most engine uses, U.S. Pat. No.
5,515,675 Apparatus to convert a four-stroke internal combustion
engine to a two-stroke pneumatically powered engine demonstrates an
attempt to use compressed air to power an engine. '675 is not an
internal combustion engine but a pneumatic engine which consumes
compressed air to push engine pistons in its single operating mode
to turn a crankshaft. First, the compressing air source is an
external artifice or contrivance outside of its engine cylinders.
Second, the timing of valve opening and closing is done by a
camshaft, substantially constraining the control of the valve
states solely for application of compressed air to crankshaft
power. And third, it employs a pneumatic distributor with a rotor
which opens gate valves to supply compressed air to the cylinders,
further precluding operation of any other engine modes save engine
crankshaft power from compressed air.
[0030] In another invention using compressed air to power an
engine, U.S. Pat. No. 3,980,152 Air powered vehicle claims an
engine powered by compressed air from a suspension type air
compressor, where the air compressor is operatively connected
between a vehicle's wheel and chassis harnessing the vertical
movement of the wheel due to unevenness of the road. While powering
engines with compressed air has been an environmentally laudable
idea, no air-powered engines have reached a practical standalone
design or seen adoption to internal combustion engines as hybrids.
What is needed are air-powered engines that can be powered with
compressed air or by burning an air-fuel mixture, thus saving fuel
and reducing environmentally harming gases produced from internal
combustion engines. What is also needed are ways to take currently
engine-discarded compressed air and re-direct that to compressed
air energy useful applications.
Other Vehicle Applications Using Compressed Air
[0031] Motor vehicle systems themselves need a source of compressed
air to operate their air brakes, air suspensions, automatic
maintained air pressure tires, conformable air seats, re-usable
airbags, etc. Automatically maintained air pressure tire systems
require a source of compressed air to keep tires inflated. Ways are
needed to produce a compressed air source for the myriad
applications driven by compressed air. Furthermore, vehicles and
vehicle power plants have many potential pneumatic applications
currently using electrical power such as starting motors, window
opening-closing mechanisms, etc., pneumatic applications which can
benefit from a readily available compressed air source.
Air Compressors
[0032] Air compressors use gas or electric motors to compress air.
Commercial uses of compressed air from mobile sources for building,
and street contractors are well known and extensively used by a
growing building and construction industry. Usually, this requires
an expensive and separate gas or electric powered mechanical unit
be brought to the work site. These vary in power and air volume
needs depending on the application.
[0033] Almost all tools today for private or commercial use are
powered by either electrical or pneumatic power. The pneumatic
tools require a compressed air source. Hundreds of vendors supply
thousands of various designs and capacities of air compressors,
pneumatic tools requiring various capacities of compressed air,
pneumatic tool components and other portable pneumatic equipment.
There is a growing market for pneumatic tools, which is predicated
on some source of compressed air, mobile or stationary.
[0034] A market that continues to grow, as pneumatic applications
grow, offers the need for air compressors of various power, size,
and capacity. Air compressors are continually advancing in the
reliability and utility that they provide. However, they do need to
be leased or purchased as separate units. These compressed air
sources are based on the size of the job and length of time needed.
There are thousands of pneumatic tools for home, commercial and
recreational uses. From small 5 CFM capacity hand paint sprayers to
110 CFM capacity air hammers, capacity for tools and needs differs,
determining the size of the air compressor source required. Because
their use and need is variable and job dependant, planning and
investment must be made in order to make economical use of air
compressors.
[0035] Private uses for pneumatic tools and applications have
increased over the years. Today, home repairs and maintenance can
require rental or purchase of air compressors for such applications
as sand blasting or spray painting the family home. Garage and home
tools are also prime candidates for pneumatic applications.
[0036] Currently, these pneumatic applications require an
independent air compressor and air storage tank, which typically
includes an electric motor-driven reciprocating piston that
compresses air and stores the compressed air in a tank. Since the
basic four-stroke internal combustion engine produces vacuum,
compressed air, power and exhaust, what is needed is an engine that
can be reconfigured dynamically such that engine cylinders can
produce power, compressed air and vacuum in a re-usable form and on
demand. What is needed are engines which produce and store
compressed air for later engine re-use and or use in external
applications where a ready source of compressed air is available
without the extra effort, ad-on equipment and expense of an
external compressed air source.
Suction Pumps
[0037] Suction pumps and siphon applications generally require
specialized equipment be brought in to siphon or collect debris.
Work places need to be cleaned and vacuum is a good mechanism to
collect debris and work by-product. Suction pumps serve many useful
purposes in cleaning up spills or siphoning flooded volumes. These
require some independent device such as a motor to be obtained to
collect or gather scattered matter or fluid from one place to
another. Since one of the strokes of a four-stroke engine (commonly
called intake stroke) acts to suction, what is needed are ways to
convert a four-stroke engine into a suction device when needed.
Engine Utility
[0038] Much has been done to improve internal combustion engines
but there is still untapped utility in an internal combustion
engine. What is needed is a utility engine analogous to a utility
vehicle. An internal combustion engine which can go off regular
power mode and provide utility needed for more than just power,
such as compressed air or vacuum for external applications is
needed. Since the current internal combustion engine has four
strokes, what is needed are ways to fully utilize all of those
strokes in alternate ways to increase the internal combustion
engines usefulness.
SUMMARY OF THE INVENTION
[0039] Internal combustion engines with electronically controlled
engine components are programmed to operate individual engine
cylinders with component states and stoke sequences that provide
alternate modes of engine operation. In doing so, a dynamically
re-configurable engine provides functions which are currently done
with external devices, add-ons or energy wasteful engine functions
in pursuit of engine power generation. By dynamically reconfiguring
a multi-stroke internal combustion engine, it is possible to
generate compressed air that can be used to increase the engine
power and efficiency, used for various vehicle pneumatic
applications, and used for external applications requiring
compressed air.
[0040] The present invention discloses a dynamically
re-configurable multi-stroke internal combustion engine, comprised
of electronically programmable computer control system for
decoupling the four classic strokes of an internal combustion
engine and independently managing engine cylinder components
including such engine components as electronically controllable
valves, fuel injection and air fuel mixture ignition, allowing
engine cylinder unit component states to be independently altered
to change stoke sequences by electronic means to provide alternate
engine operation modes. Some alternate engine modes are implemented
by addition of a compressed air storage reservoir to receive
cylinder unit compressed air or to transfer compressed air to
cylinder units. Cylinder unit isolation from the compressed air
storage reservoir is maintained through electronically controllable
valves which meter compressed air into cylinders and compressed air
out of cylinders. Sensor input and on-demand requirements drive
control logic to manage engine strokes through control of
individual cylinder component states. Dynamic reconfiguration of
individual component states provides alternate engine modes of
operation such as re-generative engine energy modes, boost power
mode, and mixed modes, which add utility and efficiency to
otherwise constrained four-stroke power generation internal
combustion engines.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] These and other features and advantages of the present
invention will become more apparent to those skilled in the art
from the following detailed description in conjunction with the
appended drawings in which:
[0042] FIG. 1 is an engine cutout view illustrating a dynamically
re-configurable internal combustion (DRIC) engine cylinder unit in
accordance with an embodiment of the present invention.
[0043] FIG. 2 is a high-level engine system diagram of a DRIC
engine in accordance with an embodiment of the present
invention.
[0044] FIG. 3 shows a high level DRIC engine controller block
diagram in accordance with an embodiment of the present
invention.
[0045] FIG. 4 is a timing diagram illustrating a Power Mode
according to an embodiment of the present invention.
[0046] FIG. 5 is a timing diagram illustrating Compression Braking
Mode according to an embodiment of the present invention.
[0047] FIG. 6 is a timing diagram illustrating Boost Power Mode
according to an embodiment of the present invention.
[0048] FIG. 7 is a timing diagram illustrating Compression Start
Mode and Compression Idle Mode according to an embodiment of the
present invention.
[0049] FIG. 8 is a timing diagram illustrating Re-generative
Compression Braking Mode according to an embodiment of the present
invention.
[0050] FIG. 9 is an engine block cutout view illustrating a DRIC
engine cylinder unit according to a vacuum generation embodiment of
the present invention.
[0051] FIG. 10 is a timing diagram illustrating a Vacuum Mode
according to an embodiment of the present invention.
[0052] FIG. 11 is an engine block cutout view illustrating a DRIC
engine cylinder unit in accordance with a three valve embodiment of
the present invention.
[0053] FIG. 12 is a timing diagram illustrating Compressed Air
Production Mode according to a three-valve embodiment of the
present invention.
[0054] FIG. 13 is a schematic of a vehicle having a DRIC engine and
an engine control system for controlling the DRIC engine according
to an embodiment of the present invention;
[0055] FIG. 14 is a high level flow chart of a method for
controlling a DRIC engine coupled to the operation to a vehicle in
accordance with an embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0056] Through decoupling and altering of cylinder component states
and and stroke sequences, a multi-stroke internal combustion engine
is created to perform any number of useful functions in addition to
applying power to a crankshaft. With the combined advent of
computer processors, electronic fuel injection, electronic
ignition, and electronic intake and exhaust valve actuation in
internal combustion engines, it is possible to electronically and
independently control an internal combustion engine's fuel in,
ignition timing, air in, exhaust out, and air-fuel mixture,
independently and changeably in real-time to individual cylinders.
Thus, by computer programmed control of these components, an aspect
of the invention dynamically reconfigures an internal combustion
engine's cycles for the purposes of creating alternate modes such
as regenerative braking, power boost, compressed air engine start,
engine fuel-less idle and general air compression or suction for
internal or external use applications. These various engine modes
are facilitated with the use of a compressed air storage reservoir
operatively connected to the internal combustion engine to provide
storage of engine produced compressed air. This compressed air can
be re-introduced to the engine for modes such as engine power
boost, engine idle, engine start or used for external compressed
air applications currently requiring a separate and mobile air
compressor.
[0057] An aspect of the present invention provides vehicle engine
regenerative braking through programmed logic which determines the
number of engine cylinder units, informed by various signals such
as speed, rate of braking, descent incline angle, weight of
vehicle, etc. to operate in air compression mode to decelerate the
vehicle while storing up compressed air for alternate use.
Compressed air from compression braking may be later re-introduced
into engine cylinders for increased power demands such as for
incline loads or for generally faster acceleration. This is
accomplished by reconfiguring an internal combustion engine from a
power cycle to a compression cycle at microprocessor speed,
virtually in real-time. This allows an engine's power requirements
and load functions to be altered dynamically to take full advantage
of vehicle circumstantial momentum, inertial energy conditions and
engine load requirements by re-configuring the operation of an
engine.
[0058] Essentially, an aspect of the invention provides a
programmable computer means for starting, transitioning and
controlling individual cylinder units for selected modes of
operation, wherein a mode is comprised of settable cylinder unit
component states, sequences of strokes and computer programmed duty
cycles. These modes of operation are selected from a set of modes
further discussed below labeled power mode, compression start mode,
re-generative compression brake mode, boost power mode, vacuum
mode, compression idle mode, compressed air production mode,
compression braking mode and combinations of these modes.
Dynamically Re-Configurable Internal Combustion (DRIC) Engine
Basics
[0059] FIG. 1 is a partial engine block cutout view illustrating a
dynamically re-configurable internal combustion engine cylinder
unit in accordance with an embodiment of the present invention. The
cylinder 106, cylinder ring 108, piston 104, cylinder expandable
volume 105, exhaust valve 117 and air inlet valves 111 and 109,
fuel injector 115, fuel mixture igniter 113, compressed air inflow
electronically controlled valve 103 and actuator 101, cylinder
compressed air outflow check valve 107, air intake 191, exhaust
manifold 193, compressed air reservoir 102, electronic actuation
devices 110 119 comprise a Cylinder-Piston Compression-Power Unit
(CPCPU) in a preferred embodiment. These components are
independently operated under a computer control system.
Specifically, a CPCPU is controlled by electronic fuel injection,
electronic means for igniting a fuel air mixture, electronic means
of controlling outlet and inlet valves, and fluid communication
channels for compressed air from cylinder to compressed air
reservoir and vice versa. Not shown if FIG. 1 but FIG. 2 and FIG.
3, are internal and external sensors under electronic control which
take and deliver signals to cylinder components operating under
programmable logic and processor control.
[0060] Other embodiments of the invention use piston-cylinder
configurations such as in a rotary engine, where the cylinder is
exchanged for a conformable volume which functions in similar
fashion to rotate a crankshaft upon gas expansion. The present
invention can be adapted to CPCPUs working in-line, opposed, vee,
or radial configurations. Also not precluded from the present
invention are non-spark ignition engine configurations such as
diesel engines, which can be adapted as well even though compressed
air with fuel mixture does not require electronic ignition for fuel
mixture ignition.
Camless Electronically Controlled Inlet and Exhaust Valves
[0061] An aspect of the invention uses camless intake and exhaust
valves under an electronic control system. Camless valves have only
recently been commercially available. Valve motion can be
effectuated electronically in two ways, solenoid actuation or
fast-acting electro hydraulic. In one preferred embodiment of the
DRIC engine, the inlet 111 and exhaust 117 valves use solenoid
actuation 110 119 respectively. In another embodiment, a
fast-acting electro hydraulic actuator under the control of an
electronically controlled digital valve is used to provide the
mechanical power for valve actuation. Engine inlet and outlet
valves and associated electronic actuators are CPCPU specific
components whose open-close states are controlled by a computer
control system.
Fuel-Air Mixture Ignition
[0062] In an aspect of the invention, the fuel-air mixture ignition
means depends on the type of four-stroke internal combustion
engine. In a gas engine embodiment CPCPU, the fuel mixture igniter
113 receives a signal to ignite the fuel-air mixture in power mode
generally near top dead center (TDC) of the power stroke. In this
embodiment of the invention, a solid-state electronic ignition
system is used in conjunction with electronic sensor signals and
feedback signals to a central ignition module to produce a spark of
a precise duration and time to a particular CPCPU in accordance
with the engine mode and associated timing required. These are
known to one skilled in the art and provide the means to introduce
spark to ignite the air fuel mixture by computer control.
[0063] A diesel DRIC engine embodiment would, as in a diesel
engine, produce a much higher compression and therefore a hotter
compressed air for fuel mixing. Injecting fuel into a diesel CPCPU
would, because of the high pressure, ignite the air-fuel mixture
spontaneously. Therefore spark is not required to ignite the
fuel-air mixture and reliance on fuel injection time to initiate
power stroke would be used instead for a diesel DRIC embodiment.
Since a diesel DRIC embodiment in boost mode introduces compressed
air from CAS 102 via a valve into the combustion chamber of the
CPCPU through the inlet valve 111, a compression stroke will
increase the heat and pressure of the air mixture even more than in
a typical diesel cycle, and therefore a denser air, which will burn
additional fuel for additional power. A diesel engine embodiment
can be programmed in boost power mode similar to the gas engine
embodiment boost power mode but without the necessity of electronic
ignition, but with reliance on fuel injection timing for air-fuel
ignition from compressed air spontaneous combustion. This mechanism
provides the ignition means component in a diesel DRIC engine
embodiment.
Electronically Controllable Compressed Air Inlet Valves
(ECCAIV)
[0064] The ECCAIV 103 is a solenoid valve under electronic
processor control which commands the amount and density of air
which will enter the cylinder volume 105 through the inlet valve
111 in accordance with selected duty cycles and modes. The ECCAIV
103 provides metered compressed air in power boost mode for a
larger but stoichiometic burn, but also serves in other engine
modes as required for compressed air needs. In other embodiments,
the delivery of the required amount of air at a known density would
be calculated based on processor input signals such as engine RPM
and current power requirements and also such computer storage
factors as mean effective pressure for the particular engine,
compression ratio, mechanical efficiency, thermal efficiency,
torque requirements, mode of engine operation, etc. Essentially,
each CPCPU is isolated from stored compressed air reservoir by an
electronically controllable valve capable of metering compressed
air from CAS reservoir into cylinders. The ECCAIVs are also CPCPU
specific components whose on-off states are programmably controlled
by the computer control system.
Electronic Fuel Injection
[0065] Processor controlled fuel injection systems are currently
designed and used by those skilled in the art for directing
calculated fuel quantities to be injected into engine cylinders. In
an aspect of the invention, based on input sensor information,
engine mode, selected CPCPU, stroke and duty cycle logic
information, the computer control system directs the fuel injector
115 to inject the calculated quantity of fuel at the time and for
duration in accordance with a mode duty cycle based in part on fuel
injector characteristic parameters, crankshaft position and engine
speed. Although there are engine-operating conditions where
air-fuel ratio requirements have priority over emission control,
stoichiometric air-fuel ratios are thought to be the best for
achieving both optimum fuel efficiency and optimum emission control
under ideal conditions and are programmed into the fuel injection
control logic. In an embodiment of the invention, processor control
of the inlet air volume from ambient and compressed air sources and
the fuel quantity entering the cylinder is maintained based on
power demands without the dependence on ambient air density alone
for fuel-air mixture. An aspect of the invention provides optimum
air-fuel ratios that are not constrained by the air density from
ambient air or from turbos because compressed air can be introduced
in known quantities and pressures. Metered compressed air quantity
from electronic control compressed air inlet valve ECCAIV 103 can
be combined with metered fuel from the fuel injector 115 for
selected CPCPU power at exact stoichiometric ratios. Since the
source compressed air pressure is known from sensor data and the
ECCAIV 103 characteristics are known, the compressed air and hence
oxygen density can be calculated to meter precise quantities of air
into the cylinder. Essentially, programmed computer logic controls
fuel injector 115 component states in concert with ECCAIV 103
component states allow known pressure compressed air to flow
through the ECCAIV 103 and calculated electronic fuel injector 115
fuel quantity based on injector characteristics, engine
characteristics and digitized stoiciometry tables for a
stoiciometric or other air-fuel mixture combustion. These are known
to those of ordinary skill in the art.
Inlet Check Valve
[0066] The inlet check valve 109 provides a means of switching
between a CPCPU receiving ambient air or compressed air. In another
DRIC engine embodiment this means can take the form of an
additional electronically actuated cylinder valve. In the FIG. 1
embodiment illustration, check valve 109 provides the means to
prevent back-flow of compressed air. It also allows air from intake
manifold 191 to flow to the cylinder volume 105 in normal power
mode. In this embodiment of the invention, inlet airflow is
controlled by local pressure conditions allowing one-way cylinder
bound flow of ambient air from inlet manifold to the CPCPU. In
other embodiments, the inlet check valve 109 can be controlled by
electronic actuation for more optimal flow characteristics or
alternate engine designs.
Compressed Air Storage Check Valve (CASCV)
[0067] In an embodiment of the invention, following a piston 104
compression stroke, in selected modes of operation, the CASCV 107
serves to allow compressed air to flow through the inlet valve 111
port to CAS plenum 102 for compressed air storage. In another
embodiment, the compressed air to cylinder communication could take
a more direct approach, routing directly to the cylinder through an
additional electronically actuated cylinder valve. In yet another
embodiment, the ECCAIV 103 and the CASCV 107 could be merged into a
multi-way valve. Essentially, the compressed air storage reservoir
is charged by one or more cylinder units via inlet valve 111 and
CAS check valve 107 component open states. The CASCV allows
compressed air to flow uni-directionally from cylinders into
compressed air storage reservoir in accordance with a computer
programmed mode of a particular CPCPU operation. The CASCV are
CPCPU specific components whose operating states are, in this
embodiment, controlled by local pressure conditions allowing
one-way flow of compressed air from a CPCPU to the CAS.
[0068] This embodiment depicts a dynamically re-configurable multi
stroke internal combustion engine coupled to the operation of a
vehicle, comprising one or more cylinder units each with piston
expanding and contracting cylinder volume. Each cylinder unit
having an intake port and associated electronically controllable
intake valve component, said intake valve component states under
computer processor control. Each cylinder unit having an exhaust
port and associated electronically controllable exhaust valve
component, with the exhaust valve component states under computer
processor control. Each cylinder unit having an electronic fuel
injector component with the fuel injector component states under
computer processor control. Each cylinder unit having an air-fuel
mixture ignition means, with the ignition means under computer
processor control. Each cylinder unit having a switching means for
either expelling contracting cylinder volume compressed air for
alternate use or for combusting compressed air-fuel mixture for
power stroke with the switching means under computer processor
control. A computer control system comprising one or more computer
processors executing programming logic in accordance with mode
defining cylinder unit component states, executing programming
scenario logic responsive to sensor signals for changing cylinder
unit component states in accordance with programmable select modes
of operation such that the internal combustion engine cylinder unit
component states are controlled to provide engine changeable
cylinder unit stroke sequences generating crankshaft power or
compressed air for alternate use.
[0069] Compressed air is a potential energy source where the
compressed air provides a pressure differential to ambient air
pressure that can be used for doing useful work. Compressed air
alternate use is defined here as those compressed air applications
not currently used in motor vehicles such as for compressed air
production, regenerative compressed air braking, compressed air
engine starts, compressed air engine idle, compressed air power
boost and for external compressed air applications.
4-CPCPU DRIC Engine Embodiment
[0070] FIG. 2 is high-level diagram of a 4 CPCPU DRIC engine in
accordance with an embodiment of the present invention. A
four-stroke, intake-compression-power-exhaust, internal combustion
engine functioning in four fundamental strokes when normally
configured will deliver at least 4 effects; suction, compression,
power and exhaust. By de-coupling the four stroke power cycle of
some CPCPUs and re-configuring the cylinder valve component states
of other CPCPUs, including such things as cessation of fuel
injection and spark, an internal combustion engine can generate
compressed air or vacuum for other applications. Compressed air
storage 201 provides a reservoir for engine-produced compressed
air. The CAS has a control valve 290 to regulate outside engine
compressed air utility and also communicates with the engine
through a charge air plenum 202.
[0071] In the invention embodiment shown in FIG. 2, cylinders
receive intake air from ambient air manifold 291. In power mode,
cylinders work under a firing sequence that is controlled by
programmable control logic. This is notably distinguished from a
preset unchangeable firing sequence constrained by mechanical
design.
[0072] In a DRIC embodiment, CPCPUs are operated independently, but
substantially similarly individually during a given operational
mode. In a power mode utilizing all CPCPUs, intake air passes
through inlet check valves 209 229 249 and 269 to the inlet valves
211 231 251 and 271 which are independently processor controlled
through actuators 210 230 250 and 270 respectively. Inlet ambient
air is mixed with fuel from injectors 215 235 255 275 respectively
under processor control. The power stroke is initiated with the
compressed air-fuel mixture ignited by processor-controlled
ignition through spark initiators 213 233 253 and 273 respectively
in accordance with a computer controlled firing sequence. This
drives the pistons sequentially to impart rotational energy to the
crankshaft for power. Exhaust valves 217 237 257 277 are
independently processor controlled through actuators 219 239 259
and 279 respectively and are opened to vent exhaust gas to exhaust
manifold 293.
[0073] In power boost modes, CPCPUs are independently isolated to
accept manifold ambient air 291 through inlet check valves 209 229
249 and 269. CPCPUs independently processor controlled actuators
205 225 245 and 265 open and close ECCAIVs 203 223 243 and 263
respectively to supply compressed air from CAS 201 via the
compressed air plenum 202 to the cylinders 217, 234, 254 and
274.
[0074] In engine modes which generate compressed air for storage,
selected CPCPUs are independently controlled to generate compressed
air. A CPCPU selected for air compression has fuel injector and
spark ignition component states set to off and exhaust valves are
closed for the duty cycle duration. The inlet valve is opened and
inlet ambient air is drawn into cylinder on intake stroke. The
CPCPU inlet valve is then closed for compression stroke after which
the compressed air is expelled through the CAS check valves and
through compressed air plenum 202 for cooling 295.
Compressed Air Storage (CAS)
[0075] The CAS 201 provides a means to store energy in the form of
compressed air, which also serves as an accumulator for external
applications of compressed air. The Compressed Air Plenum (CAP) 202
communicates compressed air from the CAS 201 through the ECCAIV
203, 223, 243, and 263, through the inlet valves 211, 231, 251, 271
respectively into the cylinders 217, 234, 254 and 274. The ECCAIV
203, 223, 242, and 263 and all inlet valve actuators 210, 230, 250,
270 are under computer processor control.
[0076] The CAS 201 can be a traditional high-pressure tank or
non-traditional high-pressure container. Traditional high-pressure
tanks have become lighter without sacrificing strength by using
composite materials. Non-traditional CAS for vehicles can be in
such volumes ordinarily not considered for high-pressure air
containment such as hollow frames, high pressure tires, wall
volumes, vehicle seats, etc. A series of containers connected with
each other for a larger volume but isolated by valves, can
effectively offer accumulation of maximum pressure more quickly
without sacrificing available total storage volume. Vehicle tires
can be manufactured of strength and thickness to be used as CAS
reservoirs. Compressed air vehicle compartments and vehicle
structural components used for CAS may also benefit from internal
compressed air by adding strength and stiffness to members.
[0077] In another embodiment, the compressed air can have a
transient storage life in a CPCPU compressed air distribution
manifold, whereby compressed air produced in one CPCPU can be
communicated to another CPCPU, thereby "turbocharging" other
cylinders with enriched air without the use of a turbocharger. The
compressed air distribution and manifold can be a connecting
labyrinth with valves or a distributor directly channeling
transient compressed air communicating between source and sink
CPCPU's at appropriate times.
Compressed Air Plenum (CAP) Inter-Cooling Loop
[0078] In accordance with the laws of physics, compressing air will
also increase its' temperature. In an embodiment of the invention,
the heated compressed air may be useful at certain engine
temperatures but not in other embodiments. The embodiment shown in
FIG. 2 applies a cooling fluid loop 295 on the compressed air
plenum to keep CAS temperature within pre-set parameters.
Compressing, and subsequently cooling air, depending on
air-humidity, yields water vapor condensate. The excess water
condensate is channeled to a sump 296 and drain valve 297 for
draining 299.
Compressed Air Storage Check Valves (CASCV)
[0079] CASCV 207, 227, 247 and 267 in an embodiment of the
invention are typical check valves which insure uni-directional
flow of compressed air along a path from the CPCPU cylinders 214
234 254 174 to CAS 201.
Engine Controller
[0080] Current model automobiles and trucks use multiple processors
and some vehicles have thousands of lines of software code. There
are many engine computer programming environments which those
skilled in the art use to program aspects of the invention: the
engine control system, stoiciometry tables in digitized logic, mode
duty cycles program logic and various other program logic. The
engine control system is comprised of input sensors, electronic
control modules to process those input signals, and stored logic
and which then signals mechanical actuators to convert output
signals into physical action. A control module, referred to herein
as computer or controller, can be comprised of such components as
CPUs, controllers, micro controllers, processors, microprocessors,
memory and/or other electronic hardware.
[0081] FIG. 3 shows engine control module 399 for an embodiment of
the present invention for a DRIC engine on a vehicle and associated
inputs and outputs from devices and sensors. As shown in FIG. 3,
the engine control module 399 includes a computer or central
processing unit (CPU) 395 in communication with computer readable
storage devices 389, 391, and 393 via memory management unit (MMU)
396. The MMU 396 communicates data (including executable code
instructions) to and from the CPU 395 and among the computer
readable storage devices, which for example may include read-only
memory (ROM) 391, random-access memory (RAM) 393, keep-alive memory
(KAM) 389 and other memory devices required for volatile or
non-volatile data storage, and data buses 387 386 of any suitable
configuration. The computer readable storage devices may be
implemented using any known memory devices such as programmable
read-only memory (PROM's), electrically programmable read-only
memory (EPROM's), electrically erasable PROM (EEPROM's), flash
memory, or any other electrical, magnetic, optical or combination
of memory devices capable of storing data, including executable
code, used by the CPU 395 for controlling the internal combustion
engine and/or motor vehicle containing the internal combustion
engine.
[0082] Input/output (I/O) interface 397 is provided for
communicating with various sensors, actuators and control circuits,
including, but not limited to, the inputs shown in FIG. 3. These
inputs include device and sensor signals such as CAS Tank Pressure
301, Cylinder Knock 302, Engine Coolant Temperature 303, Crankshaft
Position 304, Ignition System 315, Transmission Gear 306, Vehicle
Speed 307, Vehicle Inclination 308, Inlet Air temperature sensor
309, Engine Speed sensor 313, Power Pedal Position 311, Brake Pedal
Position 312, and Air Compression Standalone 300. Input signals are
used as real-time variables in conjunction with the programmed duty
cycle and mode logic to control the CPCPU components in concert
with cylinder unit piston position for creating variable stroke
sequences.
[0083] The engine controller module 399 receives signals from a
variety of sensors, such as the sensors discussed above, and
controls operation of CPCPU components through outputs which
control the states of the fuel injectors 315 335 355 375, Inlet
Valves 310 330 350 370, Exhaust Valves 319 339 359 379, spark plugs
313 333 353 373, ECCA inlet valves 305 324 345 365 analogous to a
FIG. 2 embodiment CPCPU components. These outputs include Spark_4
373, Fuel_4 375, Spark_3 353, Fuel_3 355, Spark_2 333, Fuel_2 335,
Spark_1 313, Fuel_1 315, EV4 379, IV4 370, EV3 359, IV3 350, EV2
339, IV2 330, EV1 319, IV1 310, ECCAIV 305, ECCAIV2 324, ECCAIV3
345, ECCAIV4 365.
[0084] Where Spark_n represents the control line to the sub-module
ignition for cylinder n, Fuel_n represents the control line to
actuator assembly fuel injector in cylinder n, EVn represents the
control line to actuator assembly camless exhaust valve in cylinder
n, IVn represents the control line to actuator assembly camless
inlet valve for cylinder n, and ECCAIVn represents the control line
to electronic control compressed air inlet valve serving cylinder n
compressed air.
[0085] The control and operation of CPCPU component states varies
in accordance with the mode requirements, sensor input and engine
parameters. Although CPCPU embodiments of the invention are
described with components as having Boolean states of open/closed
or on/off, this is done for illustration of simple cycle of
operation purposes. In practical fact, this would be an
approximation and the physical reality of moving engine components,
even though electronically controlled and actuated, is that
components have state transition characteristics, properties and
response profiles which impact the duty cycle timing. Optimum
operational results may require initiating component state
transitions before top dead center (TDC) or after TDC and in
accordance with engine parameters. This would apply to bottom dead
center (BDC) stroke starts as well. Valves and other mechanical
components have characteristic open and close profiles. Latencies
from command execution to completed mechanical state transition
must be addressed in any real application of the invention.
Therefore, the component open/close duty cycles and timing curves
may appear substantially different from those illustrating the
simple fundamental modes of operation which when implemented may
appear different.
[0086] Sensors and devices provide information about vehicle
operating parameters that affect the operation of the vehicle, the
engine and engine mode of operation. The term "vehicle operating
parameters" herein refers broadly to any vehicle operating
parameter, including but not limited to engine operating
parameters, which are sensed, computed, derived, inferred or
otherwise provided.
[0087] The engine controller 399 is a portion of the computer
control system which comprises computer readable program code
embodied in a computer usable medium. The readable program is
executable code and programmable logic embedded in various modules
and sub-module component hardware. The programming and firmware
embedment process is well known to those of ordinary skill in the
art. The programmable portion will store engine mode information
and control transition of the engine from one mode to another mode,
or command that the engine operate in a mixed mode. Simple example
computer program logic in the form of psudo code is shown below for
engine mode transitions for typical vehicle operation.
[0088] In a present embodiment scenario; where the engine is in
power mode operation, there is vehicle speed 307 in excess of 30
mph, engine speed 313 in excess of 1K RPM and the rate of brake
demand from brake pedal position 312 exceeds X
brake_pedal_position. This combination of variables and vehicle
parameters would signal a desire to stop or slow the vehicle. This
typical driving scenario encountered by most drivers daily provides
an opportunity to convert vehicle kinetic energy into potential
energy in the form of compressed air, without wasting fuel while
slowing the vehicle. In this scenario, the engine would be
reconfigured to compress air by changing the states of the engine
components, in compliance with a change in mode, to achieve the
deceleration desired. Using sensor input variables in FIG. 3, and
engine parameters in the logic, an engine control system psudo code
snippet may be: TABLE-US-00001 IF ((Power_Mode) AND (Vehicle_Speed
> S1) AND (Engine_Speed > E1) AND (Power-Pedal_Position
>B1)) THEN { IF (CAS_Tank_Pressure > P1) AND (Brake Pedal
Position > B2) Transition_to(Compression_Brake_Mode) ELSE {
Transition_to(Re-Generative_Compression_Brake_Mode); } }
[0089] Where S1, E1, B1, P1 and B2 are settable vehicle operating
parameter constants for vehicle speed, engine speed, braking
demand, CAS tank pressure and brake threshold values respectively.
Transition_to(MODE) is a function which changes a CPCPU from a
current mode to the mode designated by the input parameter. The
transition would ensure that the piston stroke acts in concert with
the component state changes such that the changes do not work at
cross purpose with each other, but are synchronous to cylinder
unit's piston position as sensed from crankshaft position. Thus
once cylinder unit piston position at TDC is determined to occur,
the cylinder unit component states are set in accordance with the
target mode defined stroke sequence. In this scenario, the target
modes would be Compression _Brake_Mode( ) and Re-generative
_Compression_Brake_Mode( ),mode operations described in further
discussion below.
[0090] Achieving a low enough engine speed 313 coupled with
effectively zero power pedal position 311 allow the controller
logic to determine the new power requirements in a simple model. In
more complex embodiments power requirements would have more signal
inputs such as incline angle, vehicle speed and or rate of power
pedal position change. The output logic would signal the engine to
reconfigure to compressed air idle mode and hence the individual
cylinder units would set their component states in concert with
their respective piston positions in accordance with the idle mode
stroke sequence. The engine control system logic psudo code for
this simple embodiment may appear as: TABLE-US-00002 IF
((Engine_Speed < E2 ) AND (Power Pedal Position < D2)) THEN {
Transition_to (Compressed_Air_Idle_Mode)( ) ) }
[0091] Where E2 and D2 are settable engine_speed and
Power_Pedal_Position threshold logic parameter constants.
[0092] Standalone Air Compression 300 mode signal will place the
engine in a mixed power and air compression mode (if compressed air
storage (CAS) Tank Pressure 301 is below a preset air storage
pressure) to pump up the CAS pressure for alternate application
use. In this scenario, CPCPU 1 and 2 and associated components will
receive commands to maintain engine crankshaft rotation and CPCPU 3
and 4 will receive commands from the controller module 399 to run
in air compression mode to re-pressurize the CAS. A sufficiently
high CAS tank pressure 301 would signal cessation of the
compression mode until such time as the CAS tank pressure 301 falls
below a selected preset value, followed with a resumption of air
compression mode. A psudo code snippet of this scenario is:
TABLE-US-00003 WHILE((Standalone_Air_Compression) AND (P3 <
CAS_Tank_Pressure < P4)){ Transition_to(Compression_Brake_Mode)
}
[0093] Where P3 and P4 are settable pressure parameters,
Standalone_Comp_Air 300 and CAS_Tank_Pressure 301 are sensor inputs
in FIG. 3.
[0094] Thus the above scenarios illustrate an aspect of the
invention which provides means to program external events or
circumstances by way of vehicle operation parameters into engine
controller response logic alternatives by adaptive means of
altering engine operation modes changing engine configuration
dynamically to manage external circumstances with reconfigured
engine component state and stroke sequences.
[0095] In another embodiment, several input signals processed by
the computer processor would be used to optimally control delay of
spark to a cylinder relative to piston TDC. Aspects of the present
invention would add such input signal information as CPCPU number,
mode, stroke cycle, piston position, etc to the process. An aspect
of the invention provides means for computer program alterable
engine cylinder unit firing sequence where the spark initiator acts
as a component of a specific CPCPU whose on-off states are computer
controlled.
[0096] Engine component states necessary to establish the
programmable means of controlling the modes and their associated
component states and timing in concert with piston strokes are
shown below under each individual engine mode.
Reconfigurable Operating Modes
[0097] In an aspect of the invention, an internal combustion engine
with particular engine components under electronic control is
re-configured to operate in modes and combinations of modes other
than solely for producing power to turn the crankshaft. In addition
to the power operation mode, a dynamically re-configurable internal
combustion (DRIC) engine can be designed to operate in compressed
air production mode, boost power mode, compression brake mode,
compression start mode, Compression idle mode, and combinations
thereof. This not only increases the versatility of an internal
combustion engine, it also allows for higher efficiencies, lower
emissions and other benefits.
[0098] In addition to providing compressed air or vacuum for
external applications, a re-configuration of engine mode results in
energy gains under conditions that result in higher fuel
efficiencies. A more precise air fuel mixture control capable of
formulating any air-fuel ratio can be achieved with a more complete
stoichiometric combustion because the numerator, air density, as
well as the denominator, fuel quantity, are both controllable under
programmed processor control. And thus a more responsive engine
load following regime can be attained. Furthermore, precise fuel
air mixture through introduction of engine produced compressed air
at controlled air densities rather than by imprecise ambient or
unregulated mechanically generated turbocharger compressed air
densities can be achieved through programmable logic in an aspect
of the invention. Powering an engine without consumption of fuel by
re-introducing engine produced compressed air at the appropriate
piston positions as in an air driven piston motor can maintain
engine RPM as required for vehicle idle.
Alternate Engine Modes
[0099] As briefly discussed above, aspects of the invention provide
alternate engine modes. The alternate engine modes are discussed in
conjunction with component duty cycle timing diagrams. The timing
diagrams FIG. 4 through FIG. 8 show graphical depictions that only
simply express the open-closed, on-off positions, pulse durations
and duty cycles of each of the relevant engine components. These
pulse durations and duty cycles can vary substantially within a
mode's cycle to reach optimums or to comply with constraints. In
idle mode, the engine idle RPM will differ for every vehicle in
different environmental conditions and rates of obtaining and
preserving a steady pre-set idle will be controlled by the
processor by adjusting the CPCPU component states to apply the
necessary component positions to achieve the preset idle RPM. Also,
computer operation and control of the Inlet_Check_Valve 109 and
CAS_Check_Valve 107 are unnecessary in an embodiment which employs
a flapper or check valves which change state as a function of local
pressure conditions automatically, as in this embodiment and
associated modes of operation.
[0100] An embodiment of this invention includes sensors and inputs
that provide information to processors, which are programmed to
determine optimum open, close, on and off states for the components
that comprise an engine. All optimizing calculations, variables and
factors are not accounted for here because they are engine design
specific, and we only present a simple fundamental mode of
operation of an embodiment. Therefore, the component states,
durations and profiles will vary for each engine according to its
physical characteristics and that the instant invention is not
limited by the modes and states presented here.
Power Mode
[0101] FIG. 4 is a timing diagram illustrating a Power Mode
according to an embodiment of the present invention. FIG. 4 shows
the state positions 400 and duty cycles corresponding to a CPCPU
piston 404 stroke number 401, exhaust valve 417, spark 413, inlet
valve 411, inlet check valve 409, fuel injector 415, ECCA inlet
valve 403, CAS check valve 407 as a function of time during a 4
stroke cycle engine in accordance with one mode of the
invention.
[0102] In internal combustion engines, the thermal gas expansion
energy that is released when the fuel is burned is converted into
mechanical energy. A combustible mixture of fuel and air are
ignited in the cylinder that expands the gas and pushes the piston
that imparts a torque to the crankshaft. The energy needed to
effect the change of contents in the cylinder is provided by the
flywheel, which stores up some of the mechanical energy imparted by
the piston. The additional energy developed by the engine is used
at the end of the crankshaft to provide power as required by CPCPU
modes or engine load.
[0103] In an invention embodiment of a multi-stroke engine, the
first stroke 401 1-2, intake stroke, the piston 404 travels from
its effective smallest cylinder volume position, Top Dead Center
(TDC), to it's effective largest cylinder volume position, Bottom
Dead Center (BDC), by means of rotational power from the
crankshaft. During this stroke the exhaust valve 417 components is
in the closed state as the cylinder is temporarily isolated from
the exhaust manifold. The inlet valve 411 and the inlet check valve
409 components are in the open state so that ambient air can be
drawn into the cylinder. The fuel injector 415 injects fuel 400
which mixes with the introduced air from the inlet valve 411. The
ECCA inlet valve 403 and the compressed air storage (CAS) check
valve 407 are both in the closed state.
[0104] The second stroke 401 2, is the compression stroke. While
all the cylinder valves 417 411 409 403 407 are closed, the piston
404 compresses the fuel-air mixture by moving from BTC to TDC.
[0105] The third stroke 401 3 is the power stroke. While all the
cylinder valves 411 417 409 403 407 are closed, spark 413 ignites
the compressed air-fuel mixture and the pressure of the gases of
combustion forces the piston 404 to expand the cylinder volume and
in doing so imparts rotational energy to the crankshaft.
[0106] The fourth stroke 401 4 is the exhaust stroke. The exhaust
valve 417 is opened while all the other valves 411 409 403 407
remain closed and the piston 404 pushes the spent gas through the
exhaust valve 417 clearing the cylinder and completing the
cycle.
[0107] As above, each CPCPU has associated components which are
identified by CPCPU and identifying number n of CPCPU as CPCPU_n.
In the psudo code snippet below, the CPCPU_n is associated with
ECCAIVn, IVn, EVn, Spark_n, Fuel_n, CASCVn, ICVn, corresponding to
the electronic control compressed air inlet valve, inlet valve,
exhaust valve, spark, fuel, CAS check valve, inlet check valve
respectively for the nth CPCPU. The function Schedule_at( ) is
program logic executed in real-time and relies on real-time sensor
data as well as preset variables, constants and programmable logic
to determine which CPCPU component states to adjust in accordance
with applicable mode duty cycles and at the prescribed time. In the
most basic fundamental mode, PISTON_TOP_OF_STROKE.sub.--1.sup.st
will be the time at TDC for the CPCPU_N piston, which is based on a
known crankshaft position to determine an individual CPCPU piston
position as it will reach it's TDC. Component state durations will
be based on engine speed (RPM), a real-time input parameter from
sensor signals, and component specific characteristics, which
determine constants and duty cycle durations. For example the inlet
valve 411 duty cycles are depicted as relatively vertical step up
and down with flat duration during the full stroke period. This is
a simple ideal depiction made for demonstrative purposes, as
current valve characteristics generally require that the valve be
opened BTC and closing overlaping with other valve openings.
Furthermore, the stroke time or cycle duration are based on engine
speed and with other factors, used in calculating component state
durations. An simple ideal psudo code snippet for power mode would
be: TABLE-US-00004 Power_Mode( CPCPU_N ) { Schedule_at(
PISTON_TOP_OF_STROKE_1st, CPCPU_N) {
Dispatch_Exhaust_Valve_Close(CPCPU_N);
Dispatch_Inlet_Valve_Open(CPCPU_N, DT2);
Dispatch_Fuel_Injection_On(CPCPU_N, DT3);
Dispatch_ECCAIV_Close(CPCPU_N); } Schedule_at(
PISTON_BOTTOM_OF_STROKE_2nd, CPCPU_N) {
Dispatch_Inlet_Valve_Close(CPCPU_N);
Dispatch_Fuel_Injection_OFF(CPCPU_N); } Schedule_at(
PISTON_TOP_OF_STROKE_3rd, CPCPU_N) {
Dispatch_Spark_Ingnition(CPCPU_N); } Schedule_at(
PISTON_BOTTOM_OF_STROKE_4th, CPCPU_N) {
Dispatch_Exhaust_Valve_Open(CPCPU_N, DT1); } }
[0108] Where DTx are the pulse width times roughly calculated
DT1=(Stoke/Rev).times.(Fraction of EV stroke duty
cycle).times.(60)/(Engine_Speed) DT2=(Stoke/Rev).times.(Fraction of
IV stroke duty cycle).times.(60)/(Engine_Speed)
DT3=(Stoke/Rev).times.(Const1).times.(function(CAS_Pressure))/Engine_Spee-
d)
[0109] Const1=ECCAIV property constant
[0110] Stroke/Rev=stroke period per crankshaft revolution
[0111] Engine_Speed=engine RPM input
[0112] In power mode, an aspect of the invention provides
programmed computer control actuation of cylinder unit component
states in conformity with programmed power mode duty cycles
responsive to engine power demand requirements, engine RPM and
cylinder unit piston position progress through intake, compression,
power and exhaust strokes to provide the required power to the
crankshaft. Component state duration times DT1, DT2, DT3 are
determined by controller calculations in real-time from
formulations based on vehicle operating parameters such as engine
speed and CAS pressure, and also in accordance to duty cycle
characteristics. Injector duration in open state, DT3, has a
additional term which models the flow characteristics of the
particular injector device and in this embodiment is only roughly
based on pressure but will generally have many engineering
characteristic parameters to be taken into account in calculations
of optimal duration time. Here, the DT3 calculation is more
representative of an ECCAIV open state duration calculation and is
used here to illustrate the breath of calculation types
contemplated in aspects of the invention. Further more, generally,
these types of simple formulations and calculation methods are thus
applied to other modes of operation in calculating component open
or close state durations and are related in time to associated
piston stroke sequences.
[0113] In power-generating modes, the engine firing order is
changed by programming logic scheduling cylinder unit stroke
sequences by setting select cylinder unit component states such
that cylinder unit strokes sequence through
intake-compression-power-exhaust independently of other cylinder
units while maintaining cylinder unit volume expansion in concert
with compatible crankshaft positions. Firing order may be changed
to achieve various means and purposes such as mixed mode operation,
transitioning CPCPUs between modes, failure mitigation, engine
vibration and other purposes.
Compression Braking Mode with Compressed Air Storage Tank Full
[0114] FIG. 5 is a timing diagram illustrating Compression Braking
Mode with Compressed Air Storage Tank Full according to an
embodiment of the present invention. FIG. 5 shows the state
positions 500 and duty cycles of a CPCPU piston 504, exhaust valve
517, spark 513, inlet valve 511, inlet check valve 509, fuel
injector 515, ECCA inlet valve 503, CAS check valve 507 as a
function of time during a two stroke cycle 501 in accordance with
an aspect of the invention.
[0115] In brake mode, there is an immediate need for the engine to
reverse the direction of power transmission from pistons to the
crankshaft to from the crankshaft to pistons. ie. the engine
consumes vehicle or engine flywheel momentum to provide engine work
or alternatively, power is taken from the crankshaft when the
pistons do work compressing air. Since power and exhaust stroke are
not used in this mode, the compression and intake strokes are all
that are required to in this mode. Furthermore, if the CAS tank is
full, the compressed air is vented through the exhaust
manifold.
[0116] Beginning with an intake stroke when the piston 504 is at
TDC of its stroke 501-1 heading towards cylinder volume expansion
501-2, exhaust valve 517 state is closed, no spark 513 is given,
the inlet valve 511 and inlet check valve 509 are fully opened for
ambient air which is drawn into the cylinder. During intake stroke
501-1, fuel injector 515 is turned off, ECCA inlet valve 503 and
the CAS check valve 507 are closed. In compression stroke 501-2,
spark 513, fuel injector 515 remain off, ECCA inlet valve 503 and
CAS Check Valve 507 remain closed, Inlet valve (IV)511 and inlet
check valve 509 are closed although inlet check valve 509 can
remain open throughout this mode as well. Towards the tail end of
the compression stroke 501-2 the exhaust valve (EV) 517 is opened
for a short fraction of the duty cycle to vent compressed air to
exhaust manifold. In another embodiment of the invention, regulated
communication between CPCPUs intake manifolds can direct compressed
air from a compression stroke of one CPCPU to the compression
stroke of another CPCPU to multiply the compressed air pressure
simultaneously, resulting in greater engine stopping power.
[0117] A simple exemplar psudo code snippet for programmable logic
control of engine components establishing a compression mode for an
individual CPCPU N is as follows: TABLE-US-00005
Compression_Brake_Mode ( CPCPU_N ) { Schedule_at(
PISTON_TOP_OF_STROKE_1st, CPCPU_N) {
Dispatch_Exhaust_Valve_Close(CPCPU_N);
Dispatch_Inlet_Valve_Open(CPCPU_N, DT2);
Dispatch_Fuel_Injection_OFF(CPCPU_N);
Dispatch_ECCAIV_Close(CPCPU_N); } Schedule_at(
PISTON_BOTTOM_OF_STROKE_2nd, CPCPU_N) {
Dispatch_Inlet_Valve_Close(CPCPU_N);
Dispatch_Exhaust_Valve_Open_Period(CPCPU_N,DT3,DT4); } }
DT2=(Stoke/Rev).times.(Fraction of IV stroke duty
cycle).times.(60)/(Engine_Speed) DT3=(Stoke/Rev).times.(Fraction of
compression stroke duty cycle closed).times.(60)/(Engine_Speed)
DT4=(Stoke/Rev).times.(Fraction of compression stroke duty cycle
opened).times.(60)/(Engine_Speed)
[0118] Stroke/Rev=stroke period per crankshaft revolution
[0119] Engine_Speed=instantaneous engine speed FIG. 3, 310
Boost Power Mode
[0120] In Boost Power Mode, not unlike with turbocharged air, the
engine is supplied oxygen rich compressed air instead of ambient
air so that more fuel can be burned for a higher effective mean
piston pressure and hence stronger power stroke. FIG. 6 is a timing
diagram illustrating boost power mode according to an embodiment of
the present invention. FIG. 6 shows the state positions 600 and
duty cycles of a CPCPU piston 604, exhaust valve 617, spark 613,
inlet valve 611, inlet check valve 609, fuel injector 615, ECCA
inlet valve 603, CAS check valve 607 as a function of time 602
during a 4 stroke cycle engine in accordance with an aspect of the
invention.
[0121] Beginning a cycle when the piston 604 is at TDC 601-1
heading towards cylinder volume expansion 601-2, exhaust valve 617
is closed, no spark 613 is given, the inlet valve 611 is open and
inlet check valve 609 is open to ambient air. ECCA inlet valve 603
is opened, for duration based on CAS pressure and oxygen required
in conjunction with fuel quantity to burn, at the end of intake
stroke 601-1 and the beginning of compression stroke 601-2. Fuel
injector 615 is metered on in proportion to the combined ambient
and compressed air. The CAS check valve 607 is closed throughout
this mode as compressed air from the CAS is flowing from the CAS
into the cylinder. The compression stroke 601-2 has the piston 604
rising, exhaust valve 617 remaining closed, inlet valve 611 closed
and ECCA inlet valve 603 remains open part way into the compression
stroke 601-2. The end of the compression stroke 601-2 and beginning
of power stroke 601-3 signals a spark 613 that initiates a power
stroke which transfers power to the crankshaft. The following
exhaust stroke 601-4 has an opened exhaust valve 617 which vents
exhaust gas to the exhaust manifold.
[0122] Essentially, boost power mode provides programmed computer
control actuation of cylinder unit component states in conformity
with programmed boost power mode duty cycles responsive to engine
power demand requirements, engine speed and cylinder unit piston
position progress through compressed air intake, compression, power
and exhaust strokes whereby a cylinder unit receives metered
compressed air from a compressed air storage reservoir and
proportionately larger fuel quantity is metered in accordance with
a computer programmed fuel-mixture ratio function resulting in
higher cylinder energy combustion for increased power.
[0123] Metering compressed air from CAS reservoir to cylinder units
would require determining the ECCAIV upstream pressure, CAS,
calculating ECCAIV open state duration time, and opening ECCAIV
component at the required time and for the calculated duration. The
timing requirements are based at least in part on the instant
crankshaft position, starting from a known cylinder unit piston
position relative to TDC, and in accordance with the assigned mode
stroke sequence. The ECCAIV component open state duration would be
determined based partly on the device flow characteristic
parameters, device response profile, upstream CAS pressure and
other factors. These factors are device specific and will generally
have many engineering characteristic parameters to be taken into
account in calculations of optimal metering duration time. A simple
model would include the engine speed, mode stroke duty fraction and
flow characteristics based on upstream compressed air pressure,
CAS, roughly calculated as DT3 above in the Power Mode for the
injector component, but with ECCAIV device parameters. The flow
characteristics of a particular ECCAIV component are known to those
skilled in the art.
[0124] In another embodiment, stoiciometric fuel quantity is
metered in accordance with a computer programmed stoiciometric
fuel-mixture data resulting in higher cylinder energy combustion
and providing incrementally larger effective piston pressures in
cylinder unit for boosted power stroke with optimal pollution
emissions.
Compression Start Mode and Compression Idle Mode
[0125] FIG. 7 is a timing diagram illustrating Compression Start
Mode and Compression Idle Mode according to an embodiment of the
present invention. FIG. 7 shows the component states 700 and duty
cycles of a CPCPU piston 704, exhaust valve 717, spark 713, inlet
valve 711, inlet check valve 709, fuel injector 715, ECCA inlet
valve 703, CAS check valve 707 as a function of time 702 during
engine start and engine idle in accordance with an aspect of the
invention.
[0126] In engine start mode, the engine crankshaft is rotated from
an initial static position. This requires that the pistons,
crankshaft and flywheel need to overcome their static inertia to
achieve dynamic rotation. The engine crankshaft positions are known
from sensors, the individual positions of each piston in each
cylinder-piston compressor-power unit (CPCPU) are also known. In
compression start mode, the control logic will determine which
CPCPUs are in the appropriate piston positions from crankshaft
angle and will apply the duty cycle in FIG. 7 based on where piston
pistons are in their logical duty cycle positions. As CPCPU pistons
reach TDC, CPCPU components will be engaged to apply compressed air
to the pistons forcing them to apply torque to the crankshaft.
CPCPUs not engaged in application of air pressure to their
respective pistons would be rendered in minimum resistance
component states. CPCPUs with pistons in these unhelpful positions
would have their exhaust valves 717 open and inlet valves 711
closed or vice versa so that no CAS energy is lost at those times
and the piston does no compression work on compression stroke.
[0127] Beginning with a CPCPU in compression start cycle from
piston 704 up 700 at minimum cylinder volume 701-1. No spark 713 is
initiated through-out this mode. The inlet valve 711 and the ECCA
inlet valve 703 are opened to provide compressed air to push on the
piston 704 for crankshaft rotation. The exhaust valve 717 is closed
700 so that compressed air would work against the piston without
venting. The inlet check valve 709 and CAS check valve 707 are both
closed through-out the duration of this mode. There is no fuel
injection 715 as the purpose is to rotate the crankshaft to
sufficient RPM to switch the engine to power mode without the use
of battery power to turn a starter motor. On the second stroke
701-2 from a BDC, the exhaust valve 717 would be opened to vent the
cylinder-uncompressed air without working against the piston.
[0128] Compression Start Mode starts the engine by initiating
engine crankshaft rotation with application of compressed air
pressure on cylinder unit pistons disposed in positive power to
crankshaft positions through admittance of compressed air into
volume expanding cylinder units in accordance with start mode logic
defining cylinder unit component states and computer processor
program logic execution responsive to engine start signal,
crankshaft RPM and crankshaft position.
[0129] In Compression Idle Mode, the requirement is that the engine
crankshaft continues to rotate to preserve a steady engine
operating inertia on "hot" standby so that when power from the
engine is required, it will not have to overcome the large inertial
forces of the engine to start, only the frictional forces to
accelerate. Currently, idle is ordinarily accomplished by burning
fuel at low engine RPM rates. An aspect of the current invention is
to use stored compressed air for pushing pistons in idle mode to
save from using fuel in power strokes during idle. Therefore, in
idle mode, an engine controller maintains the speed of the
crankshaft in accordance with the inertial demands that provide
continued rotation by withholding fuel injection and spark but
operatively introducing compressed air into the CPCPUs which have
pistons positioned to cooperatively turn the crankshaft. Thus in
any crankshaft position, some of the CPCPUs will be in those
cooperative piston dispositions and some of the CPCPUs will be in
air-compression dispositions. Since the crankshaft position is
known and related to each CPCU disposition, exact individual CPCU
disposition is known and the controller can operatively push
compressed air into cylinders which will turn the crankshaft at a
preset speed. A preset speed can be maintained by feedback from the
rate of rotation sensor to control the amount of compressed air
introduced into individual cooperating CPCPUs.
[0130] A simple exemplar snippet of programmable logic in the form
of psudo code for processor control of engine components
establishing an Compressed Air Idle Mode where direct compressed
air is used to turn the crankshaft without fuel for an individual
CPCPU n follows directly. TABLE-US-00006 Compressed_Air_Idle_Mode(
CPCPU_N ) { Schedule_at( PISTON_TOP_OF_STROKE_1st, CPCPU_N) {
Dispatch_Exhaust_Valve_Close(CPCPU_N);
Dispatch_Inlet_Valve_Open(CPCPU_N, DT2);
Dispatch_Fuel_Injection_OFF(CPCPU_N);
Dispatch_ECCAIV_Open(CPCPU_N); } Schedule_at(
PISTON_BOTTOM_OF_STROKE_2nd, CPCPU_N) {
Dispatch_Exhaust_Valve_Open(CPCPU_N);
Dispatch_Inlet_Valve_Close(CPCPU_N, DT2);
Dispatch_ECCAIV_Close(CPCPU_N); } }
DT2=(Stoke/Rev).times.(Fraction of IV stroke duty
cycle).times.(60)/(Engine_Speed) [0131] IV=Inlet Valve [0132]
Stroke/Rev=stroke period per crankshaft revolution [0133] Engine
Speed=instantaneous engine RPM [0134] Fraction of IV duty
cycle=optimized portion of stroke needed for state change to
accomplish transfer of compressed air
[0135] Compressed Air Idle Mode maintains engine crankshaft
rotation by application of storage compressed air pressure on
cylinder unit pistons disposed in positive power to crankshaft
positions with said compressed air application responsive to
crankshaft rotation timing at said pre-set engine speed through
programmed computer control of cylinder unit component states in
concert with the mode sequence strokes.
Re-Generative Compression Brake Mode
[0136] FIG. 8 is a timing diagram illustrating Re-Generative
Compression Braking Mode, compression braking with Compressed Air
Storage Tank Not full according to an embodiment of the present
invention. FIG. 8 shows the component state positions 800 and duty
cycles of a CPCPU piston 804, exhaust valve 817, spark 813, inlet
valve 811, inlet check valve 809, fuel injector 815, ECCA inlet
valve 803, CAS check valve 807 as a function of time 802 in a
multi-stroke engine in accordance with an aspect of the
invention.
[0137] As in compression braking w/CAS Tank Full, sensors signal an
immediate need for the engine to reverse the direction of power
transmission from power to the crankshaft to power from the
crankshaft. Power is taken from the crankshaft when the pistons do
work compressing air. The difference here is that the compressed
air is stored in the CAS for later use. Since power and exhaust
stroke are not needed in this mode, compression and intake strokes
are all that are required. Therefore, exhaust valve 817 is closed
for to majority of this embodiment duty cycle except as discussed
below, no spark 813 is given for the entire mode and fuel injection
815 is also turned off for the entire mode. In an embodiment where
the compressed air in the channel to compressed air storage impedes
the inlet check valve 809 from opening, the exhaust valve 817 is
cycled in very short pulses to vent any entrained compressed air
that may cause residual backpressure at the intake check valve 809
resisting the intake check valve 809 state transition.
[0138] In this embodiment of Re-generative Compression Brake Mode
the cylinder unit stroke-state switching means for either expelling
contracting cylinder volume compressed air for alternate use is
accomplished by setting CPCPU component states for compressed air
expulsion 801-3 or for combusting compressed air-fuel mixture for
power stroke CPCPU component states set as per 401-3 shown above in
power operation and boost power 601-3 modes. In Re-generative
Compression Brake Mode, the switching means is implemented with the
cylinder unit components working in concert under computer
processor control to expell compressed air to the CAS for alternate
use.
[0139] For transferring the compressed air to CAS, the ECCA inlet
valve 803 also stays closed during the entire mode as compressed
air is being stored. The inlet valve 811 remains open for the
entire cycle. Since the CAS tank is not full in this mode, the
compressed air is flowed to the CAS via the CAS check valve 807.
Beginning a cycle when the piston 804 is at TDC of its cycle
position 801-1 heading towards cylinder volume expansion, the Inlet
Valve 811 and Inlet Check Valve 809 are fully opened for ambient
air that is drawn into the cylinder. Also in intake stroke, the
ECVC Inlet Valve 803 and the CAS Check valve 807 are closed because
ambient air pressure is less than CAS pressure. Directly following
the compression stroke 801-2, CAS Check Valve 807 remains closed,
Inlet valve 811 and inlet check valve 809 also remain closed. In
some embodiments of the invention, regulated air flow communication
between CPCPUs can conduct compressed air from a compression stroke
of one CPCPU to the end of the intake stroke and the beginning of a
the compression stroke of another CPCPU to further compress the
compressed air, simultaneously providing even greater engine
stopping power with pistons working against higher pressure
air.
[0140] Although the alternate use in this embodiment of
Re-generative Compression Brake Mode is for compressed air
production transferred to the CAS, in another embodiment,
distribution of the compressed air is made to other cylinder units
through direct channels, bypassing the CAS or to external
application direct use, also bypassing the CAS.
[0141] A simple exemplar snippet of programmable logic in the form
of psudo code for processor control of engine components
establishing a Compression Brake Mode with CAS Not Full where
compressed air is stored for an individual CPCPU N follows
directly. TABLE-US-00007 Re-generative Compression_Brake_Mode (
CPCPU_N ) { Schedule_at( PISTON_TOP_OF_STROKE_1st, CPCPU_N) {
Dispatch_Exhaust_Valve_Close(CPCPU_N);
Dispatch_Inlet_Valve_Open(CPCPU_N, DT2);
Dispatch_Fuel_Injection_OFF(CPCPU_N);
Dispatch_ECCAIV_Close(CPCPU_N); } Schedule_at(
PISTON_BOTTOM_OF_STROKE_2nd, CPCPU_N) {
Dispatch_Inlet_Valve_Open(CPCPU_N, DT2);
Dispatch_Exhaust_Valve_Period(CPCPU_N, T1); } }
DT2=(Stoke/Rev).times.(Fraction of IV duty
cycle).times.(60)/(Engine_Speed) T1=(Stoke/Rev).times.(1-(Fraction
of IV duty cycle)).times.(60)/(Engine_Speed)
[0142] Computer operation and control of the Inlet_Check_Valve and
CAS_Check_Valve are not necessary in a design which employs a
flapper or check valve which change state as a function of local
pressure conditions automatically as in this embodiment. Thus the
ECCAIV is maintained closed and the CAS_Check_Valve allows cylinder
compressed air to flow to the CAS. [0143] Stroke/Rev=stroke period
per crankshaft revolution [0144] Engine_Speed=instantaneous engine
RPM 310, FIG. 3 [0145] Fraction of IV duty cycle=optimized portion
of stroke duration, needed for state change to accomplish transfer
of compressed air
[0146] Essentially, re-generative brake compression mode operation
provides programmed computer control actuation of cylinder unit
component states in conformity with programmed re-generation brake
compression mode duty cycles responsive to brake demand
requirements, engine speed and cylinder unit piston position,
extracting work from the crankshaft by receiving, compressing and
storing air in compressed air reservoir for subsequent engine or
alternate compressed air use.
Vacuum Mode
[0147] Instead of intake stroke drawing in air for compression and
power, an embodiment of the invention re-configures the engine into
a vacuum pump, which draws a vacuum that can supply less then
ambient air pressure on demand, for suction or siphon
applications.
[0148] Vacuum can be an energy storage mechanism where a pressure
differential can do useful work. Applications requiring vacuum for
such things as an external suction pump, for a pressure
differential to draw flow or for creation of vacuum for engine
braking all provide alternate uses for a vacuum.
[0149] FIG. 9 is a partial engine block cutout view illustrating an
aspect of a dynamically re-configurable internal combustion engine
cylinder unit in accordance with another embodiment of the present
invention. The cylinder 906 with cylinder head 908 and expandable
cylinder volume 907, piston 904, camless electronically controlled
exhaust valve 917 and actuator 919, camless electronically
controlled inlet valve 911 and actuator 910, inlet check valve 909,
electronically controlled fuel injector 915, camless electronically
controlled vacuum valve 921 and actuator 920, vacuum check valve
923 directing vacuum to suction manifold 922, electronically
controlled fuel mixture igniter 913, compressed air inflow
electronically controlled valve 903, compressed air cylinder
compressed air outflow check valve 907, connectivity to fluid
cavities and passages to air intake 991 exhaust manifold 993 or
compressed air reservoir 902, comprise a Cylinder-Piston
Compression-Power Unit (CPCPU) for this embodiment. The third
cylinder valve, vacuum valve 921, is used to facilitate another
CPCPU function, creation of a vacuum for alternate uses. As in the
above embodiments, although these CPCPUs operate in concert, they
are independently controlled under a computer control system.
[0150] In vacuum mode, the control system outputs commands to
electronically controlled CPCPU components for the vacuum mode
generally as follows. The state of the vacuum valve 921 at a
cylinder-piston expandable volume 907 appropriate to the vacuum
requirements is executed via electronic control of vacuum valve
actuator 920. Inlet valve 911 remains closed throughout this
programmed duty cycle. With inlet valve 911 and exhaust valve 917
closed, the piston 904 travels to expand the volume creating a
vacuum, which upon opening of the vacuum valve 921 will communicate
the vacuum through the vacuum check valve 923 to suction manifold
922. Thus, power is taken from the crankshaft as it performs work
on expanding the CPCPU volume to create a vacuum. Moreover, the
vacuum mode can be useful in engine braking as well, if compressed
air storage is full and additional engine brake power is required,
wherein vehicle inertia turns the crankshaft providing vacuum work
to slow a vehicle.
[0151] FIG. 10 is a timing diagram illustrating a Vacuum Mode for
the embodiment of the present invention described immediately above
in FIG. 9. FIG. 10 shows the component state positions 1000 and
stoke cycles 1001 of a CPCPU beginning with piston 1004, exhaust
valve 1017, spark 1013, inlet valve 1011, Inlet Check Valve 1009,
fuel injector 1015, ECCA Inlet Valve 103, CAS Check Valve 1007 and
vacuum valve 1021 as a function of time 1002 during a two-stroke
cycle in accordance with an aspect of the invention.
[0152] Non changing CPCPU component states for the vacuum mode are
Spark 1013 off and fuel injector 1015 off. Inlet valve 1011, inlet
check valve 1009, ECCAIV 1003 and CASCV 1007 respective component
states are closed throughout this mode. During the first stroke
1001-1, the piston starts from TDC, valves 1017 1011 1021 to the
cylinder are closed and the piston 1004 is pulled by the crankshaft
to expand the cylinder-piston work volume to create a vacuum. The
second stroke 1001-2 begining at BDC and proceeding to reduce the
cylinder volume of the vacuum created does so with the vacuum valve
1021 state open by actuator 922. The vacuum is communicated to the
vacuum manifold and at TDC the cycle is complete. CPCPUs operating
in vacuum mode under programmed computer control actuation of
cylinder unit component states in conformity with programmed Vacuum
Mode duty cycles are responsive to engine suction head
requirements, engine RPM and cylinder unit piston position.
[0153] Yet another embodiment of the invention with a vacuum mode
is configurable with two cylinder electronic valve components,
inlet and exhaust valve with their associated actuators, and
additional valves upstream of the inlet check valve essentially
taking on the function of communicating vacuum between the cylinder
and vacuum manifold analogous to cylinder compressed air with the
CAS, separately and at operable times.
Three-Valve Embodiment
[0154] An aspect of the invention provides each cylinder unit with
a stroke state switching means for either expelling contracting
cylinder volume compressed air for alternate use or for combusting
retained compressed air-fuel mixture for a power stroke. An
embodiment of the invention depicted in FIG. 11 employs three
electronically controllable cylinder valves, and associated
cylinder unit components under electronic control to provide the
means to perform this switching. This third electronically
controllable cylinder valve, facilitation valve, in concert with
the inlet and exhaust valves regulates compressed air to and from
the cylinder volume. The facilitator valve takes over the function
of the CAS Check Valve and ECCA Inlet Valve of the FIG. 1
embodiment, providing the means for electronic control of cylinder
unit component state settings to build sequences of strokes to
create alternate engine modes of operation.
[0155] FIG. 11 is an engine cutout view illustrating an embodiment
of a dynamically re-configurable engine cylinder unit in accordance
with a three valve embodiment of the present invention. The
components shown in FIG. 11 are: processor controlled electronic
ignition 1113, electronically controlled fuel injector 1115 which
is shown inside the cylinder unit for inclusion and not design
since most gas engines use a port injector and diesel engines use
direct in the cylinder or pre-chamber injectors. Other CPCPU
components include camless electronically controlled air inlet
valve 1111 and associated actuator 1110, ambient air inlet 1191,
cylinder 1106 with changeable cylinder volume 1105, cylinder head
1107, camless electronically controlled exhaust valve 1117 and
attached actuator 1119 acting to regulate expulsion of exhaust
between cylinder 1106 and exhaust outlet 1193, piston 1104 and
piston rings 1108. These all in addition to a camless
electronically controlled facilitator valve 1121 and attached
actuator 1120 controlling compressed air flow to and from
compressed air source 1123 comprise a Cylinder-Piston
Compression-Power Unit (CPCPU) embodiment and are as in previous
embodiments independently operated under a computer control
system.
[0156] While the FIG. 1 two-valve cylinder embodiment employs an
associated CAS check valve for outgoing compressed air and an
electronically controllable compressed air inlet valve (ECCAIV) for
metering incoming cylinder air, the FIG. 11 embodiment creates a
substantially similar functionality with the electronically
controlled facilitator valve component having multiple states under
computer processor control. The facilitator valve open state timing
and duration allows metering of compressed air to and from
compressed air source and cylinder, which facilitates the engine
alternate uses. The time and period that the facilitator valve 1121
remains open is depends which way the compressed air will flow. It
can be a function of the pressure of the compressed air source, and
is determined by computer logic and allows metering at programmed
time the amount of compressed air introduced to the cylinder volume
from compressed air source through compressed air channel 1123. The
cylinder component states are under computer control and programmed
with a defined mode of operation to provide the means to switch
from one stroke to a subsequent programmed stroke. As with the
facilitator valve 1121, control program logic accepts external
signals such as crankshaft positions, engine RPM and real-time
demand inputs in determining time and duration of each component
state and for state transitions.
[0157] FIG. 12 is a simple timing diagram illustrating Compressed
Air Production Mode according to a three valve in cylinder unit
embodiment of the present invention. FIG. 12 lists the component
state positions 1200 and stroke positions 1201, piston 1204,
exhaust valve 1217, spark 1213, inlet valve 1211, fuel injector
1215, and facilitator valve 1207 of a CPCPU as a function of time
1202 during a two-stroke cycle in accordance with an aspect of the
invention.
[0158] The computer contol system outputs commands to the
electronically controlled components in Compressed Air Production
Mode component states generally as follows: spark 1213 and fuel
injector 1215 states are off and the exhaust valve 1217 is closed.
During the first stroke 1201-1, the piston 1204 starting from TDC,
inlet valve 1211 is open and the piston 1204 is pulled by the
crankshaft to expand the cylinder volume to draw in ambient air.
The second stroke 1201-2 starts at BDC, the inlet valve 1211 is
closed and the piston 1204 proceeds to contract the cylinder volume
and hence compress the air. During this compression stroke, the
faciliator valve is opened and closed towards the end of the stroke
to expel the compressed air into the compressed air channel 1123
for alternate compressed air uses.
[0159] As in previous embodiments, in this embodiment the CPCPU
component states are set through sensor inputs and programmed logic
based on required engine modes and mode duty cycles to meet vehicle
signal requirements such as compressed air demand or compressed air
braking. Sensor inputs such as crankshaft position inform the
control system when each cylinder unit is at piston TDC, a natural
time to begin many stroke sequences. However, the stroke start time
not constrained to TDC and can begin before or after TDC. The
changes in engine RPM sensor signals the control system whether
mode changes in some cylinder units were sufficient to meet demand
changes for power or braking. For example, vehicle incline or
engine detonation signals inform the engine control logic when
conditions trigger demand for compressed air production or smart
mode initiation respectively. The computer control system includes
timing or duty cycle logic which programmably defines what cylinder
component states must exist and when in time they must be set to
establish the required stroke sequence for compressed air
production.
[0160] Although the alternate use in this embodiment for compressed
air production can be triggered from vehicle braking signal,
compressed air can be produced for alternate external uses even
with the vehicle at stop, from Air Compression Standalone Mode
signal. The crankshaft provides the power to compress the air and
that power can come from other CPCPUs in power mode or boost power
mode. In an embodiment without the CAS, distribution of the
compressed air is made directly to external applications.
[0161] FIG. 13 is a schematic of a vehicle having a DRIC engine and
an engine control system for controlling the DRIC engine in
accordance with the present invention. As will be appreciated by
those of ordinary skill in the art, the present invention is
independent of the particular underlying engine configuration and
as such can be used with a variety of different internal combustion
engines having different engine configurations and other vehicle
parameters. The engine for example can be constructed and arranged
with one or multiple cylinders as a diesel or gasoline engine used
for generating power, or as a DRIC engine operating to store or
re-generate vehicle inertia. Similarly, the present invention is
not limited to any particular type of apparatus or method required
for changing the operating stroke sequences of internal combustion
engines or altering the cylinder firing order of internal
combustion engines.
[0162] Referring again to FIG. 13, the engine includes a plurality
of cylinders (only one shown), each cylinder 1306 having a
combustion chamber 1307, a reciprocating piston 1304, electronic
compressed air valve actuator 1303, electronic intake valve
actuator 1311, electronic facilitator valve actuator 1320 and
electronic exhaust valve actuator 1319, compressed air plenum 1373,
ambient air inlet 1371, vacuum plenum 1375 and cylinder discharge
1377 respectively. The piston 1304 is coupled to a connecting rod
1352 which itself is coupled to a crankpin 1354 of a crankshaft
1350. Fuel is injected to the combustion chamber 1307 via a fuel
injector 1315 and is delivered in quantities metered by an
electronic driver circuit 1316 under commands from the engine
controller 1399 (or equivalent). Ambient air 1371 is nominally
drawn via a controlled intake check valve 1309 disposed within the
intake manifold. Ignition spark is provided to ignite fuel-air
mixture via spark plug 1313 and ignition system 1314 in accordance
with a spark advance (or retard) signal from the electronic
controller 1399 in response to but not limited to engine detonation
signal 1302. Fuel mixture ignition can also be obtained by
spontaneous combustion of injected fuel where the vehicle engine is
of the diesel type and combustion time is predictable from fuel
injection time.
[0163] As shown in FIG. 13, the engine controller 1399 nominally
includes a microprocessor or central processing unit (CPU) 1395 in
communication with computer readable storage devices 1393 1391 and
1389 via memory management unit (MMU) 1396. The MMU 1396
communicates data (including executable code instructions) to and
from the CPU 1395 and among the computer readable storage devices,
which for example may include read-only memory (ROM) 1391,
random-access memory (RAM) 1393, keep-alive memory (KAM) 1389 and
other memory devices required for volatile or non-volatile data
storage. The computer readable storage devices may be implemented
using any known memory devices such as programmable read-only
memory (PROM's), electrically programmable read-only memory
(EPROM's), electrically erasable PROM (EEPROM's), flash memory, or
any other electrical, magnetic, optical, wireless or combination
memory devices capable of storing data, including executable code,
used by the CPU 1395 for controlling the DRIC engine and to some
extent the vehicle hosting the DRIC engine. Input/output (I/O)
interface 1387 is provided for communicating with various sensors,
actuators and control circuits, including but not limited to the
devices shown in FIG. 13. Input devices include an engine speed
sensor 1310, crankshaft position 1318, cylinder detonation sensor
1302, engine coolant temperature 1303, power pedal position sensor
1311, brake pedal position sensor 1312, and CAS pressure.
[0164] Output command and control includes electronic fuel control
driver 1316, ignition system 1314, electronic compressed air valve
actuator 1303, electronic intake valve actuator 1311, electronic
facilitator valve actuator 1320 and electronic exhaust valve
actuator 1319. These outputs are shown for one cylinder unit but
would apply for each cylinder unit in the engine and are used to
control the states for the cylinder components in concert with
associated piston to generate stoke sequences from programmed modes
of operation.
[0165] The sensors shown provide information about events,
conditions and vehicle operating parameters 1379 that affect the
scheduling of engine mode invocation from a plurality of engine
modes. The term "vehicle operating parameters" herein refers
broadly to any vehicle operating parameters, including
engine-operating parameters, which are sensed, computed, derived,
inferred or otherwise provided. Other vehicle sensors not listed in
the present embodiment are not precluded from application by this
invention. Modes of operation are comprised of engine component
state configurations that define strokes and in concert, stroke
sequences. The controller 1399 receives signals from vehicle
operating parameters, processes stored logic which uses the
parameters to schedule engine modes of operation in time and across
engine cylinder units in real-time.
[0166] FIG. 14 is a high level flow chart of a method for
controlling a DRIC engine coupled to the operation to a vehicle in
accordance with the present invention, a simple real-time
continuous engine control program logic. Execution begins at Start
1401 wherein upon receiving a vehicle parameter Ignition System
signal the controller logic proceeds in this embodiment to
Determine CAS & Battery Status 1403. Determining status
includes sensing and reading CAS_Tank_Pressure sensor data to
ascertain if there is sufficient pressure in the CAS for a
Compression Start Mode 1407 start. If insufficient pressure, the
controller signals the battery start the engine. If the Engine On
logical 1405 is false, control execution branches to Compression
Start Mode 1407 where upon the engine is started on compressed air
from CAS in accordance with the Compressed Air Start Mode. The
program logic will then query whether a vehicle parameter such as
Compressed Air Standalone Mode signal was received which in the
affirmative will branch to a Compressed Air Production Mode 1411,
placing the engine in a mode which will supply compressed air to
CAS reservoir for external applications requiring compressed air
without the vehicle otherwise operating. A CAS tank low-pressure
signal will initiate Compressed Air Production Mode 1411 to
recharge the CAS. Standalone Compressed Air Production Mode would
require engine power mode in some cylinder units sufficient to
compress air in other cylinder units as defined by those modes.
[0167] If the Engine On 1405 is true, as sensed from positive
vehicle parameter Ignition signal and Engine Speed sensor, the flow
of execution proceeds to Determine Vehicle Power Requirements 1413.
In a simple fundamental model, power requirements are determined
from the receipt of Pedal Position signal. In more complex
embodiments, parameters such as Engine Speed, Crankshaft Position,
available compressed air CAS tank pressure or engine and other
vehicle parameters can also serve to establish how many engine
cylinder units will need to initiate Power Mode 1419 unless greater
power from a Boost Power Mode 1417 is required. Greater and higher
rates of pedal power position, larger vehicle include angles, low
engine speed and other factors will generally dictate more cylinder
units in power or boost power mode in accordance with programmed
logic.
[0168] The program logic will proceed to determine vehicle-braking
requirements 1423. Determine Vehicle Braking Requirements 1423 can
diverge along two general paths, to use engine compression braking
and friction braking in series or in parallel. While engine
compression braking first and friction braking second in sequence
would be a more energy re-generative approach and less wearing on
the friction brake components, this is not the simplest approach
because vehicle friction brakes have become more sophisticated,
some using computer controls with sensors which add complexity to a
sequential application. Therefore a fundamental mode of operation
for the present invention would be to apply engine compression
braking in parallel with friction braking. The trigger for braking
can come from a variety of signals and devices. Such signals from
sensors or devices providing information available for determining
vehicle-braking requirements can be from but are not limited to;
brake pedal position change per time, brake line fluid pressure
change per time, deceleration rate from accelerometer, wheel
rotation sensor signal, brake temperature change per time, vehicle
inclination sensor signal, brake temperature sensor, and historical
brake data stored in KAM, RAM, ROM, etc. Reception of a brake
signal will execute the inquiry as to CAS Tank pressure 1425. If
the CAS is not full the program will configure the engine to
Re-Generative Compression Brake Mode 1429, otherwise to Compression
Brake Mode 1427 subsequently branching back to the main loop.
[0169] The program logic will continue to determine if the vehicle
should be in hot standby 1433. In a simple fundamental model, this
is established by absence of Pedal Position signal. More complex
logic can factor in such vehicle parameters as Engine Coolant
Temperature, Vehicle Speed, Engine Speed, etc. If hot standby is
called for and there is available CAS_Tank_Pressure, then the
Engine Idle 1435 query is affirmed and the program will execute an
Compressed Air Idle Mode 1437. This will allow the engine to run by
compressed air, conserving fuel and cooling the engine. If
sufficient compressed air is unavailable, CAS_Tank_Pressure is less
than the requisite level, a low RPM Power Mode 1439 will be
invoked. Execution will then branch back to query if an engine stop
1441 signal has been received. Reception of an engine kill signal
will branch the program logic to stop 1443 the engine, absent that
to continue systematically executing for further triggering changes
at 1405.
Mixed Mode Operation, CPCPU Mode Transitions and Load Balancing
[0170] Since power is developed during only one stroke in the power
mode, a single CPCPU multi-stroke engine has a low degree of
uniformity and the rotation of the crankshaft is subject to
considerable accelerations and decelerations during a complete mode
cycle. For this reason multiple cylinder engines are useful because
they produce smoother running engines.
[0171] In an aspect of the invention, the CPCPU firing order is
designed to reduce vibration and engine rocking thus improving
engine wear, balance and smoothness of operation. However, the
firing order is changeable in accordance to the CPCPU modes of
operation in fulfilling requisite programmed scenario requirements.
Therefore in an embodiment of the present invention, power strokes
would be scheduled to be evenly staggered along the crankshaft
among the individual CPCPUs, so that power strokes are developed
not necessarily successively but uniformly in consideration of mode
of operation, engine vibration and other vehicle paramters.
Therefore, in an embodiment of the invention operating in more than
one mode, Power Mode in some CPCPUs and Compression Mode in other
CPCPUs, Compression Mode CPCPUs are selectively interspersed
between the Power Mode CPCPUs whereby power strokes are optimally
located along a succession path with other strokes and modes of
engine operation which are more likely to damp crankshaft vibration
and or the shift crankshaft vibration frequency content to less
engine wearing frequencies. The balancing mode sequence and CPCPU
firing order are engine parameter specific and are mentioned here
as additional optimizing benefits from operations in
mixed-mode.
[0172] Within the mechanical continuity of the basic
crankshaft-piston rod-piston-cylinder position constraints, the
present invention embodiment computer control system can transition
individual CPCPUs between operating modes in virtually real-time.
Since the DRIC is under processor control, electronic sensor,
processor response time and electronically controlled CPCPU
components under computer control are orders of magnitude
(nanoseconds) shorter than can be accomplished with mechanical
control components (milliseconds) where even practicable. The
electronic switching latency times controlling mechanical component
states shorten the difference but electronic switching retains
sufficient margin over mechanical switching to allow flexibility
and speed required for the dynamic re-configuration to occur.
Switching modes for a particular CPCPU would occur instantaneously
relative to the engine RPM. Although switching modes for a
particular CPCPU can likely be implemented most efficiently when
the piston position is nearing the TDC of a stroke, a CPCPU mode
change can be initiated at any part of the engine crankshaft angle
or position. Initiation of mode is also dependant upon computer
system latencies and mechanical component response delays. These
know characteristics and engine parameters can be anticipated and
programably factored into control logic to correct and predict
component state timing for optimal results. A CPCPU could continue
to run or cease to function in the previous mode in anticipation of
a new program commanded mode of operation in accordance to
programmable logic based on these aforementioned factors. A simple
CPCPU transition sequence may include stopping fuel injection,
stopping spark, opening the exhaust valve and waiting for the
piston to reach top of a stroke before initiating a new mode
sequence. Alternatively, a from mode can be completed within a
crankshaft cycle and the to mode can be programmed to begin at
CPCPU TDC or some appropriate crankshaft angle where the CPCPU
piston is proximate to the top of its stroke, but optimally at the
best time to begin the mode before or after TDC.
[0173] Treating engine CPCPUs as power, vacuum or air compressor
units, engine CPCPUs can operate at different modes simultaneously
and in concert with other CPCPUs. Vehicle operating conditions
where engine timing is known, power requirements or air compression
requirements are received, sensor information is factored in, the
processor is programmed to determine how many and what modes each
CPCPU would operate in optimally, in real-time based on programmed
mode duty cycles, input mode determination logic and engine
parameters. In an embodiment where the compressed air storage
reservoir is full and power requirements are low, the control
system will program some CPCPUs to power mode and other CPCPUs
idle, thus saving fuel. However, real-time conditions and therefore
vehicle circumstances would be changed the instant another mode is
required in accordance to sensor data from vehicle operation
parameters and programmed logic responding to those inputs. For
example, if the engine is substantially in a power mode
configuration and a large braking rate demand signal is raised, the
engine controller will determine the compression braking power
required, generally in a fundamental mode of operation this
requirement would be in proportion to the brake pedal position rate
of depression. Then a mode with selected CPCPUs incorporating
compression braking would be executed to engage some or all CPCPUs
for more vehicle stopping power. In more complex embodiments,
braking requirements response logic can include CPCPU mode
transitions programmed to engage CPCPUs with delays to make vehicle
ride characteristics as even as possible.
[0174] A simple way to synchronize timing among the engine CPCPUs
would be done by using a known crankshaft position from the
crankshaft position sensor, using the relationship of individual
CPCPU piston positions to the crankshaft rotation angle. Crankshaft
position sensors are currently used to determine such things as
firing order, degrees before top dead center, when cylinders are at
TDC, spark timing, fuel injection timing and other various computer
input requirements. Crankshaft position sensors are readily
available as are electronic methods of maintaining exact crankshaft
angle for CPCPU timing, transition and mode cycle basis which are
known by one skilled in the art.
[0175] In an embodiment of the invention, engine CPCPUs can work at
different modes in an optimal programmable fashion based on input
sensor data, programmed mode operating scenarios and programmed
duty cycles for particular modes. Moreover, in transition of a
CPCPU from one mode to another, a previous mode piston stroke can
be completed as signaled by the crankshaft angle before the new
mode engages. For example, in a four CPCPU engine it may be optimal
to operate CPCPUs 1 and 3 in power mode and Cylinders 2 and 4 in
Air Compressor mode rather than to operate Cylinders 1 and 2 in
power mode and Cylinders 3 and 4 in Air Compression. However, this
may be altered if one mode contains larger crankshaft vibration
than another mode. Many factors such as engine thermal
characteristics, material stress distribution, engine vibration,
uniform component wear, engine power requirements, mode switching
requirements and other engine parameters can be considered in
operating the different CPCPUs in an optimal mixed mode
configuration.
[0176] In mixed mode operation, one or more selected engine
cylinder units are computer program controlled and operated in a
mode different from, but in concert with one or more alternate
engine cylinder units while maintaining crankshaft timing adherence
to cylinder piston position stroke continuity by electronically
setting cylinder unit component states in accordance with
programmed computer logic responsive to sensor input signals and
programmed duty cycle modes and crankshaft angle for selected
concurrent operation.
[0177] Although Re-generative Compression Brake Mode will produce
compressed air from vehicle braking with distribution to the CAS
for alternate use, compressed air can be produced for alternate
external uses from a stationary vehicle. The DRIC engine crankshaft
provides the power to compress the air and that power can also be
generated from CPCPUs in mixed modes with power mode or boost power
mode. In an embodiment of the invention, upon
Air_Compression_Standalone_Mode to the engine control system, the
DRIC engine will operate in mixed mode to provide power from some
CPCPUs to compress air in other CPCPUs for alternate external uses
as required using the CAS. In an embodiment without the CAS,
distribution of the compressed air is made directly to an external
application.
[0178] Moreover, a thee valve cylinder embodiment is expandable to
incorporate more cylinder valves such as a vacuum valve from the
vacuum embodiment directly above to facilitate the vacuum switch
means in the same cylinder unit. These functions can also be
implemented with cylinder external valves, which under computer
control of cylinder associated components would direct compressed
air or vacuum along paths necessary for the completion of their
associated modes.
Smart Internal Combustion Engines
[0179] Aspects of the invention provides for "smarter" engines as
they are not limited by fixed stroke cycle design and hence allow
for programmable mechanical options dynamically implementable. Thus
embodiments of DRIC invention engine control system provide methods
by which an internal combustion engine can more intelligently
function in more capacities than were possible through an
unchangable stroke sequence. Scenarios for smart engine response
are programmable and are coupled with alternate engine operation
modes, executed by a computer control of individual CPCPU component
states and stroke sequences which also allows for operation
circumventing certain component failures.
[0180] In addition to the modes and scenarios illustrated above,
several scenarios involving automatic loss of performance
mitigation, critical component mode failure and loss of coolant
event are addressed below.
Automatic Performance Mitigation and Control
[0181] In the event a particular cylinder ceases to function for
reasons such as malfunctioning fuel injection, faulty wiring,
electrical component failure, fouled spark plug, etc, a current
engine's power output suffers to the point that individual
component malfunction results in sluggish engine performance or
worse, triggers a common mode failure whichprecludes any meaningful
use of the engine until the malfunctioning component is repaired.
The DRIC engine provides power, exhaust, compression and vacuum
functionality on demand in virtually real-time engine
reconfiguration. Since the DRIC engine provides the capability of
independent cylinder operating modes, the malfunctioning cylinder
can be reconfigured to reroute functionality to cylinder(s) that
are not affected by the malfunctioning component and thereby
mitigating the malfunctioning components by allowing the affected
cylinder unit to continue to function in other modes which are not
affected by the malfunctioning component(s).
[0182] For example, malfunctioning fuel injector or spark plug in
CPCPU 3 would send a CPCPU lack of fuel detonation signal that
would trigger engine control system to mark CPCPU 3 for air
compression or vacuum modes only. The compressed air generated from
the "bad" CPCPU can still be used to maintain or increase overall
engine performance. Thus, while an error message can be relayed to
the operator as to the malfunction(s), the DRIC engine by virtue of
its adaptable control system can bypass the damage by
re-configuring the engine modes. Cylinder power depends on several
factors, a major factor being the mean effective pressure produced
by the air-fuel mixture burn. Since engine dimensional parameters
and variables can be stored in the engine control system memory and
the processor programmed to calculate the necessary effective
pressure and additional fuel necessary to increase power from the
"lost" unit, a processor can be programmed to calculate a new
theoretical power output for a CPCPU based on signals received from
the engine indicating that such a scenario currently exists. In
this scenario, postulating the engine an 8 cylinder engine and
currently only capable of power from 7 cylinders and clogged
cylinder injector, a gross engine power loss of 13% would be
expected. The engine sensor signals and programmed logic would
execute to trigger the DRIC control system to mark CPCPU 3 for
compressed air mode only, compressed air which would then be
distributed to incrementally enrich the air fuel mixture to the
remaining power mode CPCPUs to increase their respective power by
2.7% (13%/7) each. Thus, a lack of knock signal or other sensor
signals from the malfunctioning CPCPU would trigger the control
system to increase fuel to the remaining CPCPUs by approximately
2.7% (or the stoiciometric proportion) automatically mitigating for
the malfunction reducing engine power. The control system would
direct additional compressed air to be metered through the power
mode cylinder associated ECCAIVs to increase air to stoiciometric
proportions and hence the component failure in a CPCPU does not
increase pollutant emissions while maintaining same power levels.
Alternatively, the malfunctioning cylinder unit could still
function in compressed air power mode or other non fuel power
modes. Of course, some components are totally CPCPU debilitating,
and perhaps a designed reliability in critical path component
reliability would lead to even more reliabble internal combustion
engines.
Smart Engine Control in Common Mode Failure Mitigation
[0183] A fair percentage of vehicles, from a variety of causes,
undergo loss of engine coolant at a time and place where they
cannot quickly cool down the engine with external coolant.
Depending on the severity of the leak and coolant rate of loss,
residual engine heat and added engine heat from fuel burn heat, the
engine temperatures can increase to levels sufficient to crack
engine cylinder heads, block or worse. In scenarios such as these,
a DRIC engine, with a reservoir of cool compressed air directed
under a smart engine control system to shift into Compressed Air
Idle Mode would cool down the cylinders and cylinder heads with
compressed air, absorbing the residual engine heat to further
expand the compressed air for additional effective piston pressure,
in a compressed air mode providing continuing vehicle locamotion
while allowing engine cooling directly at the source of peak engine
temperature, the cylinders. In an embodiment of the invention, this
would be accomplished by ceasesion of fuel and spark to CPCPUs,
disengagement of power mode and engagement of Compressed Air Idle
Mode, and operatively opening and closing inlet valve and exaust
valves to take in compressed air for vehicle propulsion towards
repair location and coolant while simulaneously reducing peak
engine temperatures. Depending on engine temperature rise,
alternate Power Mode and Compression Mode in mixed mode may also be
executed.
[0184] Although gasoline and diesel fuels are mentioned in some
invention embodiments, the invention is equally applicable to
hydrogen and other combustable fuel engines. While this invention
has been described and illustrated with reference to particular
embodiments, it will be readily apparent to those skilled in the
art that the scope of the present invention is not limited to the
disclosed embodiments but, on the contrary, is intended to cover
numerous other modifications, alterations, adaptions and equivalent
arrangements may be made by those skilled in the art without
departing from the spirit and scope of the invention.
* * * * *