U.S. patent application number 12/614505 was filed with the patent office on 2010-03-18 for single nozzle injection of gasoline and anti-knock fuel.
This patent application is currently assigned to ETHANOL BOOSTING SYSTEMS LLC. Invention is credited to Paul N. Blumberg, Leslie Bromberg, Daniel R. Cohn, John Heywood.
Application Number | 20100070154 12/614505 |
Document ID | / |
Family ID | 39324968 |
Filed Date | 2010-03-18 |
United States Patent
Application |
20100070154 |
Kind Code |
A1 |
Blumberg; Paul N. ; et
al. |
March 18, 2010 |
Single Nozzle Injection of Gasoline and Anti-Knock Fuel
Abstract
Fuel management system of operation of a spark ignition engine.
The system includes a source of gasoline and a source of anti-knock
fuel. A proportioning valve receives the gasoline and the
anti-knock fuel to discharge a mixture having a controlled
gasoline/anti-knock fuel ratio. A single high pressure pump
receives the mixture and delivers the mixture to an injector. A
fuel management control system controls the proportioning valve and
the injector for injection of the mixture into a cylinder of the
engine to control knock. A preferred anti-knock fuel is
ethanol.
Inventors: |
Blumberg; Paul N.;
(Southfield, MI) ; Bromberg; Leslie; (Sharon,
MA) ; Heywood; John; (Newtonville, MA) ; Cohn;
Daniel R.; (Cambridge, MA) |
Correspondence
Address: |
Nields, Lemack & Frame, LLC
176 E. Main Street, Suite #5
Westborough
MA
01581
US
|
Assignee: |
ETHANOL BOOSTING SYSTEMS
LLC
Cambridge
MA
|
Family ID: |
39324968 |
Appl. No.: |
12/614505 |
Filed: |
November 9, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11682372 |
Mar 6, 2007 |
7640913 |
|
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12614505 |
|
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60780319 |
Mar 8, 2006 |
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Current U.S.
Class: |
701/103 ;
123/445; 123/575 |
Current CPC
Class: |
Y02T 10/121 20130101;
F02D 19/12 20130101; Y02T 10/12 20130101 |
Class at
Publication: |
701/103 ;
123/445; 123/575 |
International
Class: |
F02D 41/30 20060101
F02D041/30; F02M 69/04 20060101 F02M069/04; F02M 25/14 20060101
F02M025/14 |
Claims
1. Fuel management system for operation of a spark ignition
gasoline engine, comprising: a gasoline engine; a source of liquid
gasoline; a source of liquid anti-knock fuel; a proportioning valve
receiving the gasoline and anti-knock fuel to discharge a liquid
mixture through a first conduit having a controlled
gasoline/anti-knock fuel ratio; a high pressure pump receiving the
mixture through the first conduit and delivering the mixture
through a second conduit to an injector; and a fuel management
control system for controlling the proportioning valve and the
injector for injection of the mixture into a cylinder of the engine
to control knock.
2. The system of claim 1, wherein the proportioning valve is drive
by an actuator.
3. The system of claim 2, wherein the proportioning valve is
upstream of the high pressure pump.
4. The system of claim 2, wherein the proportioning valve employs
rotation or translation of elements to vary the gasoline/anti-knock
fuel composition.
5. The system of claim 4, wherein the proportioning valve allows an
arbitrarily selected ratio of gasoline to anti-knock fuel including
either all gasoline or all anti-knock fuel.
6. The system of claim 1, wherein the fuel downstream from the
proportioning valve is purged for rapid modification of the fuel
mixture when ethanol content demand increases because of transient
to high torque.
7. The system of claim 6, where the purged fuel is returned to the
main gasoline tank.
8. The system of claim 1, further including a first low pressure
pump for delivering the gasoline to the proportioning valve, and a
second low pressure pump for delivering the anti-knock fuel to the
proportioning valve.
9. The system of claim 1, wherein the mixture is injected into the
cylinder under pulse width modulation control.
10. The system of claim 1, wherein the anti-knock fuel is ethanol
or ethanol blends.
11. Fuel management system for operation of a spark ignition
engine, comprising: a gasoline engine; a source of gasoline; a
source of anti-knock fuel; a high pressure pump receiving the
gasoline and anti-knock fuel and including two vanes for separate
pressurization of the gasoline and anti-knock fuel; a high pressure
proportioning valve receiving the pressurized gasoline and
anti-knock fuel to discharge a mixture having a controlled
gasoline/anti-knock ratio; an injector for receiving the mixture
from the proportioning valve; and a fuel management control system
for controlling the proportioning valve and injector for injection
of the mixture into a cylinder of an engine.
12. Fuel management system for operation of a spark ignition
gasoline engine, comprising: a gasoline engine; a source of liquid
gasoline; a source of liquid anti-knock fluid; a proportioning
valve receiving the gasoline and anti-knock fluid to discharge a
liquid mixture through a first conduit having a controlled
gasoline/anti-knock fluid ratio; a high pressure pump receiving the
mixture through the first conduit and delivering the mixture
through a second conduit to an injector; and a fuel management
control system for controlling the proportioning valve and the
injector for injection of the mixture into a cylinder of the engine
to control knock wherein the volume within the first conduit, the
high pressure pump and the second conduit is minimized to improve
the transient response of the fuel management system.
13. The system of claim 12, wherein the proportioning valve is
drive by an actuator.
14. The system of claim 13, wherein the proportioning valve is
upstream of the high pressure pump.
15. The system of claim 13, wherein the proportioning valve employs
rotation or translation of elements to vary the gasoline/anti-knock
fluid composition.
16. The system of claim 15, wherein the proportioning valve allows
an arbitrarily selected ratio of gasoline to anti-knock fluid
including either all gasoline or all anti-knock fluid.
17. The system of claim 12, wherein the fuel downstream from the
proportioning valve is purged for rapid modification of the fuel
mixture when anti-knock fluid content demand increases because of
transient to high torque.
18. The system of claim 17, where the purged fuel is returned to
the main gasoline tank.
19. The system of claim 12, further including a first low pressure
pump for delivering the gasoline to the proportioning valve, and a
second low pressure pump for delivering the anti-knock fluid to the
proportioning valve.
20. The system of claim 12, wherein the mixture is injected into
the cylinder under pulse width modulation control.
21. The system of claim 12, wherein the anti-knock fluid is ethanol
or ethanol blends.
22. Fuel management system for operation of a spark ignition
engine, comprising: a gasoline engine; a source of gasoline; a
source of anti-knock fluid; a high pressure pump receiving the
gasoline and anti-knock fluid and including two vanes for separate
pressurization of the gasoline and anti-knock fluid; a high
pressure proportioning valve receiving the pressurized gasoline and
anti-knock fluid to discharge a mixture having a controlled
gasoline/anti-knock ratio; an injector for receiving the mixture
from the proportioning valve; and a fuel management control system
for controlling the proportioning valve and injector for injection
of the mixture into a cylinder of an engine wherein the volume of
the mixture between the high pressure pump and the injector is
minimized to improve transient response of the fuel management
system.
Description
[0001] This application claims priority to provisional application
Ser. No. 60/780,319 filed Mar. 8, 2006, the contents of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to gasoline engines and more
particularly to a single nozzle injection system for cost
minimization and knock control.
[0003] The addition of an anti-knock fuel such as ethanol is very
attractive for producing highly efficient gasoline engines.
Anti-knock systems are known that utilize multiple sets of
injectors resulting in a complex and thus expensive system. It is
also known to inject gasoline and an anti-knock fuel such as
ethanol through the same nozzle using a single plenum and one
valve. Such an arrangement is disclosed in U.S. patent application
Ser. No. 10/991,774 filed Nov. 18, 2004. The contents of this
application are incorporated herein by reference in their entirety.
This pending patent application does not, however, disclose how to
mix the gasoline and ethanol before reaching the injector and in
particular does not disclose any means for mixing the ethanol and
gasoline so as to minimize the cost of the system through the use
of a single high pressure pump.
SUMMARY OF THE INVENTION
[0004] In one aspect, the fuel management system of the invention
for operation of a spark ignition engine includes a gasoline
engine, a source of gasoline and a source of anti-knock fuel such
as ethanol. A proportioning valve receives the gasoline and
anti-knock fuel to discharge a mixture having a controlled
gasoline/anti-knock fuel ratio. A high pressure pump receives the
mixture, pressurizes it, and delivers the mixture to an injector. A
fuel management control system controls the proportioning valve and
the injector for injection of the mixture into a cylinder of the
engine to control knock. A preferred anti-knock fuel is ethanol or
ethanol blends. In a preferred embodiment, the proportioning valve
is driven by an actuator employing rotation or translation of
elements to vary the gasoline/anti-knock fuel ratio. In one
embodiment, the proportioning valve is located upstream of the high
pressure pump. The proportioning valve preferably allows an
arbitrarily selected ratio of gasoline to anti-knock fuel including
either all gasoline or all ethanol.
[0005] In a preferred embodiment, the volume of the mixture between
the high pressure pump and the injector is minimized to improve
transient performance of the fuel management system. A preferred
embodiment also includes a first low pressure pump for delivering
the gasoline to the proportioning valve and a second low pressure
pump for delivering the anti-knock fuel to the proportioning valve.
It is preferred that the mixture be injected into a cylinder in the
engine under pulse width modulation control.
[0006] In yet another aspect, the invention is a fuel management
system for operation of a spark ignition engine including a
gasoline engine, a source of gasoline and a source of anti-knock
fuel. A high pressure pump receives the gasoline and anti-knock
fuel and includes two vanes for separate pressurization of the
gasoline and anti-knock fuel. A proportioning valve receives the
pressurized gasoline and anti-knock fuel to discharge a mixture
having a controlled gasoline/anti-knock fuel ratio. An injector
receives the mixture from the proportioning valve and a fuel
management control system controls the proportioning valve and
injector for injection of the mixture into a cylinder of an
engine.
[0007] In order to achieve fast time response, required during
transients from low torque to high torque, for example, there is a
delay due to the fuel that fills the fuel line and/or fuel rail.
One possible means of achieving fast response is to allow, by
opening of a valve, to return the fuel in the fuel rail or fuel
system back to one of the tanks Relatively small amounts of fuel
need to be flushed, allowing the fuel line and/or fuel rail to fill
with fuel with the appropriate composition. In order not to change
the composition of the anti-knock fuel, the purged fuel can be
returned to the larger gasoline tank.
BRIEF DESCRIPTION OF THE DRAWING
[0008] FIG. 1 is a schematic diagram of a first embodiment of the
invention disclosed herein.
[0009] FIG. 2 is a cross-sectional view of an illustrative
proportioning valve for use in embodiments of the invention.
[0010] FIG. 3 is a schematic illustration of another embodiment of
the invention.
[0011] FIG. 4 is a schematic illustration of a fueling management
and injection system that shows a return path from the fuel rail to
the main gasoline tank.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] With reference first to FIG. 1, gasoline from a gasoline
tank 10 is pumped by means of a low pressure pump 12 to a
proportioning valve 14 through fuel line 13. Similarly, an
anti-knock fuel such as ethanol from an ethanol tank 16 is pumped
by a low pressure pump 18 to the proportioning valve 14 through
fuel-line 19. FIG. 2 is a schematic illustration of a suitable
proportioning valve 14 in which an actuator (not shown) actuates by
rotation an inner drum 22 that decreases one stream and increases
the other. In the illustrative design, when the inner drum 22
rotates clockwise the overlapping region between gasoline fuel line
13 and the gasoline tube 22b in inner drum 22 decreases while the
overlapping region between ethanol fuel line 19 and the ethanol
tube 22a in inner drum 22 remains constant. Thus the gasoline
content of the fuel flowing into the proportional valve 14 can be
decreased after a clockwise rotation of the inner drum 22.
Conversely, when the inner drum rotates counter clockwise the
overlapping region between gasoline fuel line 13 and the gasoline
tube 22b in inner drum 22 remains constant while the overlapping
region between ethanol fuel line 19 and the ethanol tube 22a in
inner drum 22 decreases. Thus the gasoline/ethanol content of the
fuel flowing into the proportional valve 14 can be controlled by
rotating the inner drum 22. The output pipe 22c of proportional
valve 14 feeds output plenum 21 throughout all possible positions
of inner drum 22.
[0013] In the illustrative case in FIG. 2, mixing of the gasoline
and antiknock fuel takes place in the body of the inner drum 22. It
is possible to keep the two fuels separate through output plenum
21.
[0014] In this way, the ratio of gasoline to ethanol may be
controlled precisely.
[0015] Although a proportional valve through rotation is
illustrated in FIG. 2, the embodiment includes any proportional
valve that achieves control of flow ratio between ethanol and
gasoline. In particular, linear proportional valves that operate on
the same principle can also be envisioned.
[0016] One advantage of the valve shown in FIG. 2 is that in the
case that one of the two fluids is exhausted, it is possible to
close the appropriate valve to prevent liquid from one tank from
being introduced into the second tank. Thus the ethanol tank can be
isolated by counter-clockwise rotation of the inner drum 22.
[0017] Returning to FIG. 1, the output of the proportioning valve
14 which is a mixture of gasoline and anti-knock fuel is introduced
into a single high pressure pump 24. The high pressure pump 24
delivers the gasoline/anti-knock fuel mixture into a fuel rail 26
and then into injectors 28. It is preferred that injection of the
gasoline/anti-knock fuel mixture be controlled by using pulse width
modulation control of the injectors 28. In operation, the
proportioning valve 14 controls the gasoline/anti-knock fuel ratio
and pulse width modulation of the injectors is used to control the
total amount of mixture introduced into the engine.
[0018] Since the embodiment shown in FIG. 1 uses an injector for
injecting a mixture of the gasoline and anti-knock fuel, the
injector is always being used when the engine is running That is,
if ethanol has been used up and is unavailable, nonetheless the
injectors 28 continue to operate with gasoline. Therefore, the
injectors 28 are less likely to become fouled. In this embodiment,
when ethanol is exhausted the proportioning valve injects only
gasoline. Similarly, if gasoline is exhausted, the proportional
valve 14 injects only ethanol.
[0019] The embodiment shown in FIG. 1 requires injectors with
greater capacity and larger dynamic range since the flow through
them varies more than in a conventional GDI engine (ethanol flow is
substantially larger than that of gasoline for comparable power).
Variable fuel-rail 26 pressure can be used to partially address the
requirements of large dynamic loads.
[0020] Those skilled in the art will appreciate that the
configuration in FIG. 1 may result in decreased time response of
the ethanol/gasoline mixture because the mixture residing in the
region after the proportioning valve 14 (that is, in the high
pressure pump 24 and in fuel rail 26) has to be consumed before
there can be a change in the gasoline/ethanol ratio of the fuel
into the cylinders. It is therefore important to minimize the
volume between the proportioning valve 14, the high pressure fuel
pump 24 and the fuel rail 26. In conventional direct injection
systems, the time lag is about one second determined by the ratio
of the volume of the fluid between the injectors and the fuel pump
and the volumetric flow rate of the fuel. Reduced times are
possible through careful design of the injector system having
decreased volumes.
[0021] Those of ordinary skill in the art will recognize that the
proportioning valve 14 may be incorporated into the high pressure
pump 24 if desired. It is also apparent that fuel may be
recirculated for pump cooling with either the gasoline/ethanol or
both prior to mixing.
[0022] Alternatively as shown in FIG. 4, a return path for the fuel
downstream from the proportional valve 24 but upstream from the
injectors 28 can be purged by opening a valve 40 connected to the
fuel rail. The valve can return fuel to either ethanol tank 16 or
preferably to gasoline tank 10 through a return fuel line 42.
Although the composition of the gasoline in tank 10 could be
varying because of the introduction of gasoline/ethanol mixtures,
the fuel volume that needs to be purged from the injectors is
small. In order to minimize the effect, the purging occurs only
when the demand for ethanol increases, such as during transients to
higher torque, in order to prevent engine knock. The opposite
occurrence, when the engine torque decreases, does not require
purging of the fuel between the proportional valve and the
injectors.
[0023] Another embodiment of the invention will now be described in
conjunction with FIG. 3. In this embodiment, the gasoline and
ethanol are introduced into the single high pressure pump 30. In
this embodiment, the single high pressure pump 30 includes two
vanes for separately pressurizing the gasoline and ethanol. The
pressurized gasoline/ethanol then enters high-pressure
proportioning valve 32 under the control of the actuator 34 and
then proceeds into the fuel rail 26. From there, the mixture is
injected through the injectors 28 as in the case of the embodiment
of FIG. 1. A significant aspect from the present invention is that
both the embodiments shown in FIGS. 1 and 3 utilize a single high
pressure pump 24 (in FIG. 1) or 30 (in FIG. 3) resulting in a cost
effective system. Those of ordinary skill in the art will also
recognize that the injectors may have two valves with a single
nozzle (with mixing in a plenum upstream from the nozzle), or two
valves and two nozzles that would require two fuel rails.
[0024] It is also possible in this embodiment to purge the fuel
downstream from the proportional valve under conditions where a
rapid increase in the ethanol content of the fuel is required, such
as during transients to high torque. A smaller volume of fuel needs
to be purged compared with the embodiment in FIG. 1, as the
proportional valve 32 in FIG. 3 is closer to the injectors than the
corresponding valve 14 in FIG. 1.
[0025] The tendency of an engine to knock while in transition from
low to high torque is typically delayed. In part, this delay is due
to the fact that initially after the transition begins, the
cylinder walls are colder (from the lower torque operation),
minimizing knock in the early cycles of the transition to a high
torque regime. Therefore, any delay in adjustment of the fuel mix
ratio into the cylinder is partially offset by the delay of onset
of knocking conditions in the engine.
[0026] An active means to avoid knock during transients when the
system is loaded with lower fractions of ethanol than required for
avoiding knock, is to operate for short periods of time under fuel
rich conditions. Spark timing can also be retarded during the fuel
transient in the injection system. A combination of fuel rich
operation as well as spark retard can be used under some conditions
during the transient.
[0027] It is recognized that modifications and variations of the
invention disclosed herein will be apparent to those of ordinary
skill in the art and it is intended that all such modifications and
variations be included with the scope of the appended claims.
* * * * *