U.S. patent application number 09/954195 was filed with the patent office on 2002-03-21 for plasma ignition for direct injected internal combustion engines.
Invention is credited to Jayne, Michael E..
Application Number | 20020033156 09/954195 |
Document ID | / |
Family ID | 23995022 |
Filed Date | 2002-03-21 |
United States Patent
Application |
20020033156 |
Kind Code |
A1 |
Jayne, Michael E. |
March 21, 2002 |
Plasma ignition for direct injected internal combustion engines
Abstract
An apparatus and method for the creation, placement and control
of an area of electrical ionization within an internal combustion
engine combustion chamber. This area of electrical ionization is
positioned so that all of the fuel being injected into the
combustion chamber must pass next to or through the area of
electrical ionization to ensure that combustion has been initiated
for all of the fuel as it is injected. This area of electrical
ionization can be kept on as long as it is necessary to insure that
the all of the fuel that is injected into the combustion chamber
can be completely combusted. An engine equipped with this
electrical ionization device has its fuel economy enhanced by
timely, controlled, and complete combustion of all of the fuel
injected into its combustion chamber. Furthermore, the pollutant
emissions of both oxides of nitrogen and unburned hydrocarbons are
reduced dramatically. Further, cold starting capability of this
engine is greatly enhanced by a major reduction in the time
necessary for the engine to warm up and a major reduction of
pollutants created by the engine during the warm-up period.
Additionally, this method of combustion also allows the engine to
operate at a higher speed (rpm) allowing an increase in peak power
output.
Inventors: |
Jayne, Michael E.; (Amherst,
MA) |
Correspondence
Address: |
SMITH PATENT OFFICE
1901 PENNSYLVANIA AVENUE N W
SUITE 200
WASHINGTON
DC
20006
|
Family ID: |
23995022 |
Appl. No.: |
09/954195 |
Filed: |
September 18, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09954195 |
Sep 18, 2001 |
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09501788 |
Feb 11, 2000 |
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6289868 |
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Current U.S.
Class: |
123/169EL ;
123/169MG; 313/123 |
Current CPC
Class: |
Y02T 10/12 20130101;
F02B 2075/125 20130101; Y02T 10/123 20130101; F02F 3/26 20130101;
F02P 3/12 20130101; H01T 13/50 20130101; F02M 57/00 20130101; F02M
27/042 20130101; F02B 23/101 20130101; F02M 57/06 20130101 |
Class at
Publication: |
123/169.0EL ;
123/169.0MG; 313/123 |
International
Class: |
H01T 013/46 |
Claims
What is claimed is:
1. A fuel combustion initiation device for an engine, comprising:
at least three electrodes having electrode tips, said electrode
tips being disposed in at least one of a combustion chamber and a
pre-combustion chamber, said electrode tips defining an area
disposed in close proximity to a location where fuel is injected;
and a source of electrical energy that supplies said electrodes
with power, said electrode tips being arranged so that electrical
power is capable of selectively flowing from each electrode to the
other electrodes to form a zone of ionization.
2. A fuel combustion initiation device as defined in claim 1,
wherein said electrode tips form a polygon.
3. A fuel combustion initiation device as defined in claim 1,
wherein said electrode tips include six electrode tips disposed
around the location where fuel is injected.
4. A fuel combustion initiation device as defined in claim 1,
further comprising an insulated sleeve, said electrodes being at
least partially disposed in said insulated sleeve.
5. A fuel combustion initiation device as defined in claim 4,
further comprising a fuel injector disposed inside said insulated
sleeve.
6. A fuel combustion initiation device as defined in claim 1,
wherein said electrode tips being arranged so that injected fuel
must pass through as an area defined by said electrode tips.
7. A fuel combustion initiation device as defined in claim 1,
further comprising at least three high voltage electrical sources,
each of said electrical sources supplying power to one of said
electrodes.
8. A fuel combustion initiation device as defined in claim 1,
further comprising a signal generation circuit that controls said
source of electrical power to create the zone of electrical
ionization.
9. A fuel combustion initiation device as defined in claim 1,
further comprising an engine timing signal source that controls the
zone of electrical ionization by selectively energizing said
electrodes to assist combustion.
10. A fuel combustion initiation device as defined in claim 1,
further comprising a ceramic sleeve that extends from said
combustion chamber through a cylinder head, said ceramic sleeve
including wires embedded therein forming said electrodes in the
cylinder head, one end of said wires being connected to a set of
terminals for connected to said source of electrical power.
11. A fuel combustion initiation device as defined in claim 1,
further comprising an engine management computer for controlling an
engine timing signal.
Description
[0001] This new application is a continuation application of U.S.
patent application Ser. No. 09/501,788 filed on Feb. 11, 2000,
currently pending.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method and apparatus for
assuring combustion of fuel injected in a combustion chamber of an
internal combustion engine.
[0004] 2. Description of the Related Art
[0005] Diesel engines of both the 2-cycle and 4-cycle types have
enormous acceptance throughout the world and they are also the
types of engines that would benefit the most from application of
the present invention. When engine longevity and fuel economy are
more important than the power-to-weight ratio or the ability to
operate through a wide range of engine speeds, diesel fueled
engines are ideal.
[0006] Both Sir Harry R. Ricardo in his book The High Speed
Internal Combustion Engine and Charles Fayette Taylor in his two
volume set The Internal Combustion Engine in Theory and Practice
states that once the piston in a diesel engine goes more than about
one third of the way down on its power stroke, the flame in the
combustion chamber goes out. Although diesel engines have much
better fuel economy than that of gasoline engines of the same power
output, the diesel engines fuel economy is still constrained by the
time needed for complete combustion.
[0007] In an engine that is dependent upon the heat of compression
to initiate and maintain combustion, the relatively slow process of
fuel injection, mixing of the fuel with the air, and the combustion
itself must take place before the flame goes out as the piston
travels past the first third of its power stroke.
[0008] The primary cause of diesel engine pollution is its
dependence upon the heat of compression inside the combustion
chamber for initiation and maintenance of the combustion process.
Regardless of engine rpm, the actual time (not degrees of crank
rotation) that it takes for the fuel and air to mix and burn is
relatively long because diesel fuel is notoriously hard to ignite
and keep burning.
[0009] This difficulty of ignition can be demonstrated from putting
out a match by dipping it in a cup of diesel fuel. This can also be
demonstrated by placing a conventional spark plug in the fuel spray
pattern of a fuel injector. When diesel fuel is injected into a
spark plug's gap, the spark is extinguished there and the spark
then takes place outside of the combustion chamber by taking a path
outside of the spark plug ceramic insulator from its high voltage
terminal to its threaded base. The difficulty of igniting diesel
fuel with a spark plug is demonstrated further by the absence of
spark assisted diesel engines from the market.
[0010] For the heat of compression in a diesel engine to be
sufficient for the initiation of the combustion process, the
compression ratio must be relatively high. In some engines this
compression ratio is as high as 18 to 1. This results in a very
high combustion chamber pressure even before the fuel is injected
into the combustion chamber. Since combustion starts at an already
high pressure, the combustion chamber temperature and pressure
quickly increase to the point where the oxygen and nitrogen that
are naturally present in air combine to create oxides of nitrogen
(also referred to as NOx). Pollution from these oxides of nitrogen
is the primary cause of acid rain, photo-chemical smog and a host
of other very serious ecological and health problems.
[0011] The actual time needed for complete combustion to take place
in a diesel engine is the primary cause of the other main type of
pollutant emissions from diesel engine operation.
[0012] Any fuel that is not combusted or partially combusted as the
piston goes down past a third of the way down its power stroke
never gets burned. This problem becomes worse if the engine is
operating at full speed (as measured in revolutions per minute)
and/or at full power. Any partially or not combusted fuel left in
the combustion chamber when the piston travels past the first third
of the power stroke then exits through the exhaust port as unburned
hydrocarbons, partially combusted hydrocarbons, and particulate
matter, all of which together are more commonly referred to as
smoke. Making this pollution even worse is the fact that the NOx
created reacts with the water naturally present in engine exhaust
to make nitric acid. This nitric acid then in turn reacts with the
smoke to create a carcinogenic stew of truly unhealthy and
dangerous chemicals. These chemicals are so harmful that under
present Federal law, they could not be accepted by a landfill in
the form of solid or liquid waste.
[0013] Until very recently, the only "pollution control device"
that was installed on diesel engines in the United States was an
engine speed governor. The function of this governor was to make
sure that enough time was allowed during the power stroke so that
sufficient combustion took place prior to the piston traveling past
the first third of its power stroke in order to prevent the
creation of visible smoke by the engine. All too often truck
operators disable this governor so that they could squeeze a little
extra power out of their engine while going up hill or passing
other vehicles. Their ecological irresponsibility is evident from
the enormous black clouds belching out of their exhaust stacks and
left in their wake.
[0014] The Environmental Protection Agency (henceforth referred to
as the EPA) has allowed until recently for diesel engines to be
"grand-fathered" out of earlier pollution control regulations. This
was done for three reasons:
[0015] 1. Diesel engines get much better fuel economy than gasoline
engines of the same power output;
[0016] 2. The currently accepted theory of operation for diesel
engines did not allow for major changes in design that could be
applied in a cost-effective manner; and
[0017] 3. There was not any readily available alternative type of
engine design that could perform the jobs currently done by diesel
engines.
[0018] Over the last three decades this has resulted in a slower
pace of design advancement for diesel engines, especially for
pollution reduction, when compared to design advancements made on
gasoline engines. As a result diesel engine design has improved
only incrementally over the last thirty years without major
reductions in pollutant emission levels.
[0019] During the same period of time, an outstanding job of
cleaning up gasoline engines and other industrial sources of air
pollution took place. However, air pollution created by diesel
engines has remained about the same for a given amount of power
produced. This caused the relative percentage of air pollution
produced by diesel engines to become the primary cause of air
pollution in the US.
[0020] In response to this, the EPA started looking into ways to
reduce diesel engine pollutant emissions. They mentioned several
possible means to achieve this in a fact sheet issued in October
1995 (EPA 420-F-95-009a) that included "after treatment" such as
catalytic converters, fuel delivery control systems, air intake
strategies, and changing diesel fuel formulations. This was
followed in August 1998 by a Regulatory Announcement--New Standards
for Nonroad Diesel Engines (EPA 420-F-98-034) that phase in
reduction of diesel engine emissions by 66% over a ten year
period.
[0021] Very specific procedures to verify regulatory compliance of
new engine designs were put forward by the EPA in March 1999 in
their document titled Certification Guidance for Engines Regulated
Under: 40 CFR Part 86 and 40 CFR Part 89. Going through these
procedures to get an engine certified are an enormous task in
themselves and actually meeting these standards for EPA
certification is a major accomplishment.
[0022] Over the years there has accumulated a large body of prior
art that discloses a variety of approaches for providing assistance
to the diesel engine combustion process. A variety of reasons have
motivated these efforts, primarily to improve fuel economy, enhance
engine power, and reduce pollutant emissions.
[0023] Rao et al. (U.S. Pat. No. 5,307,772) discloses a means to
assist the diesel combustion process through the use of a catalyst.
This catalyst is plated onto a structure that is placed between the
pre-combustion chamber and the main combustion chamber in the
cylinder head on a diesel engine. This catalyst-coated structure is
positioned so that combusting gasses under high pressure and at
high velocities must pass through it during each power stroke.
[0024] Fukano et al. (U.S. Pat. No. 5,224,449) and Ariga (U.S. Pat.
Nos. 4,913,111 and 4,686,941) disclose improvements to
spark-assisted diesel engines that consist of inducing turbulence
to the combusting fuel-air mixture. In all three patents secondary
combustion chambers are used to create the desired turbulence to
enhance the mixing of the fuel and air. In addition to aiding the
mixing process, the turbulence also exposes the spark on the tip of
the spark plug to more of the fuel-air mixture. Although these
systems may enhance combustion to some extent, the spark plug
itself is only exposed to one specific point of the fuel-air
mixture at any given time.
[0025] McCowen et al. (U.S. Pat. No. 5,855,192) discloses
fuel-preheating elements, combustion chamber heating elements, and
a heat retention element within the combustion chamber. The
application of heat to the fuel and to the combustion chamber may
assist the combustion process, especially during cold starting, as
shown by the use of glow plugs and fuel pre-heaters in diesel
engines currently in production; but there is a drawback to the
introduction of additional heat into the combustion process in that
it will result in greater creation of oxides of nitrogen. Another
problem with this approach is the relative inefficiency of
electrical resistance heating elements in terms of the power that
they require, and their relatively short life in terms of total
hours of operation after which they need to be replaced.
[0026] Chan (U.S. Pat. No. 5,852,999) discloses another example of
creating and maintaining a spark that can be used in a spark
assisted diesel engine. A two-point electrode arrangement is
disclosed that is provided with a high frequency electrical current
to create an electrical arc inside the combustion chamber. The main
point in the disclosure by Chan is the concept of having the high
frequency arc initiated while the piston in the combustion chamber
is at bottom dead center of the compression stroke. This is done
for the purpose of reducing the voltage needed to initiate the
arc.
[0027] Casey (U.S. Pat. No. 4,111,178) and Kindermann et al. (U.S.
Pat. No. 4,096,841) both disclose reciprocating 4-cycle direct
injected spark ignited gasoline-fueled engines. The system
disclosed consists of a fuel injector and a spark plug placed in a
pre-combustion chamber with the spark timing controlled by a signal
that originates in the fuel injector.
[0028] None of these references disclose an apparatus that will
allow for the initiation of combustion for all of the fuel as it is
injected into the combustion chamber followed by the maintenance of
the combustion process to its completion in the manner described
herein.
SUMMARY OF THE INVENTION
[0029] It is accordingly an object of the invention to provide an
apparatus and method for assuring the combustion of the fuel
injected into the combustion chamber of direct injected internal
combustion engines such as diesel and gasoline engines of the
reciprocating "piston in cylinder" type as well as gas
turbines.
[0030] It is a further object of the invention to eliminate the
dependence of diesel engines upon the heat of compression to
initiate and maintain its combustion process.
[0031] It is a further object of the invention to improve the fuel
economy of direct injected engines.
[0032] According to these objects of the present invention, an area
of ionizing electrical energy (for purposes of illustration it is
referred to as a "Ring-of-Fire") is created inside the combustion
chamber directly in front of or adjacent to the fuel injector
nozzle which the fuel must pass through or next to as it enters the
combustion chamber. Additionally this Ring-of-Fire will be kept on
as long as needed so that the present invention will provide a
means for the immediate, controlled, and complete combustion of all
of the fuel injected into an engine combustion chamber.
[0033] When used in a reciprocating internal combustion engine, the
engine can completely combust its fuel earlier in the power stroke,
resulting in an improvement of fuel economy. There are at least
four reasons for this improvement in fuel economy (the first two
are discussed in greater detail later):
[0034] 1. Assuring the complete combustion of the fuel inside the
combustion chamber, when and where it does the work rather than
wasting it by allowing un-combusted and partially combusted fuel to
escape out through the exhaust port;
[0035] 2. Avoiding the endothermic chemical reaction that creates
oxides of nitrogen (NOx);
[0036] 3. Reducing pumping losses when an engine equipped with the
present invention is operating at less than full power. This is
especially important for automotive diesels since they spend much
more of their operating time cruising at partial power or idling
than they do at full power. The only time that an automotive diesel
engine is run at full power is when the vehicle is either going up
hill or being accelerated. Since the present invention assures
combustion regardless of pressure, pumping losses can be reduced by
throttling the air entering the intake manifold;
[0037] 4. Improving the effective ratio of expansion during the
engine power stroke. An engine equipped with the present invention
has the fuel burn completed earlier in its power stroke, thus
improving the effective ratio of expansion which improves thermal
efficiency.
[0038] It is also an object of the present invention to improve the
power output available from direct injected internal combustion
engines such as diesel engines. Accordingly, engines so equipped
can be run at full power while still completely combusting all of
the injected fuel much more rapidly within the combustion chamber
allowing for higher engine speed without creating unacceptable
exhaust emissions. This higher peak engine speed, as measured in
revolutions per minute (rpm), translates directly into a higher
peak horsepower.
[0039] An additional object of the present invention is to reduce
the pollutant emissions created by the operation of direct injected
internal combustion engines. Although most of the direct injected
engines in the world today are diesels, the present invention will
provide these same benefits to gasoline and alternative fueled
engines as well.
[0040] Hydrocarbon pollutant emissions are greatly reduced by the
complete and timely combustion of the fuel and air within the
engine's combustion chamber. By keeping the Ring-of-Fire on as long
as needed, complete combustion inside the combustion chamber is
assured which will improve fuel economy in addition to reducing
hydrocarbon emissions.
[0041] Due to this ability of the present invention to assure
complete combustion of all of the fuel inside the combustion
chamber, engines so equipped will produce much fewer hydrocarbon
emissions during a cold start before the engine has run long enough
to warm up. This will avoid the creation of what the EPA refers to
as the "hydrocarbon bubble" during warm-up of the engine, which is
an area of pollution control that they are especially interested
in.
[0042] The creation of oxides of nitrogen (NOx) will also be
reduced significantly, especially in diesel engines, by the use of
the present invention. Engines so equipped are freed from their
dependence upon the heat of compression to initiate and maintain
the combustion process. As a result of this, diesel engines
equipped with the present invention will dramatically reduce the
creation of NOx in three ways:
[0043] 1. The mechanically defined compression ratio can be reduced
without unacceptably degrading performance;
[0044] 2. The timing of the initiation of fuel injection can be
retarded in terms of degrees of crankshaft rotation without
unacceptably degrading performance;
[0045] 3. The rate of injection can be controlled by a closed-loop
feedback system such as an engine management computer responding in
real-time to combustion chamber pressure and temperature. Since the
present invention assures combustion of the fuel upon injection, it
becomes possible to regulate the rate of injection so that the
temperature and pressure inside the combustion chamber will be kept
below the threshold above which NOx is formed.
[0046] How this is achieved can be visualized by a graph of the
relationship between piston position during its power stroke and
the pressure inside the combustion chamber of an un-modified diesel
engine versus the graph made by the same engine after it has been
equipped with the present invention. The curve produced by the
un-modified engine would show the pressure rise inside as the
piston approached top dead center followed by a sharp rise
occurring as the fuel is being injected into the combustion
chamber. Shortly after all of the fuel has been injected, the
pressure will reach its peak after which it will start dropping
off. It is during this period of high pressure that oxides of
nitrogen (NOx) are formed. An even more precipitous drop in
combustion chamber pressure will follow this once the flame goes
out as the piston travels past the first third of its travel down
during the power stroke. Any fuel that has not been fully combusted
by this time will go out the exhaust as smoke.
[0047] In contrast, the same engine equipped with the present
invention will have all of the fuel injected into the combustion
chamber ignited as it is being injected regardless of the injection
timing and rate or the combustion chamber temperature and pressure.
Because of this, during the power stroke, the pressure and
temperature inside the combustion chamber can be controlled so that
it is maintained at a level that is just below the threshold at
which NOx is formed for as long as necessary to deliver the power
needed. This will create a flat pressure "curve" for much of the
power stroke of an engine equipped with an engine management
computer that is controlling the timing and rate of fuel injection
in conjunction with the present invention assuring the timely and
complete combustion of the fuel.
[0048] When the two piston position to pressure curves are
compared, the engine equipped with the present invention will have
a lower peak pressure while maintaining an equal or greater area
under the curve. This area under the pressure curve, not the peak
pressure, relates directly to the power produced. Any engine tuning
arrangement is a compromise between power, fuel economy, and
pollutant emissions control with the present invention offering the
engine designer unprecedented flexibility for achieving
improvements in all areas of performance.
[0049] Ruman et al. (U.S. Pat. No. 5,924,404) discloses an engine
management system for use in 2-cycle direct injected spark ignited
gasoline fueled engines. An arrangement of a fuel injector and a
conventional spark plug inside the combustion chamber which enables
a 2-cycle engine to reduce its emissions and improve its fuel
economy dramatically is disclosed. This control system could be
adapted into the present invention by incorporating the appropriate
software. It is also possible to adapt this control system for use
in a 4-cycle reciprocating internal combustion engine.
[0050] Another object of the present invention is to enhance engine
life for reciprocating internal combustion engines. Greater engine
durability is the result of lower NOx emissions and lower peak
pressures inside the combustion chamber. When NOx is created during
the combustion process, this NOx reacts with the water naturally
created by the combustion to create nitric acid. This nitric acid
accelerates engine wear, but if nitric acid production during the
combustion process is greatly reduced, engine durability is
enhanced. Reducing the peak pressure within the combustion chamber
during the power stroke has the effect of lowering the peak loads
upon the engine bearings, further enhancing durability of the
engine.
[0051] It is a further object of the present invention to make it
possible to retrofit existing reciprocating direct injected
internal combustion engines with the present invention at a minimum
of expense and time. The present invention can be installed on most
diesel engines in current use by removal of the cylinder head,
installing injector/igniter assemblies on that cylinder head,
reinstalling the modified original cylinder head, and then
installing the electronics that go with it. In most cases it will
not be necessary to either remove the entire engine from where it
has been installed or completely replace the existing cylinder
head. The importance of this retrofit application of the present
invention to reciprocating 2-cycle and 4-cycle diesel engines
cannot be overstated. The environmental and economic benefits made
possible by the present invention are expanded dramatically as a
result of it being possible to retrofit existing engines.
Reciprocating internal combustion engines retrofitted with the
present invention should benefit from all of the advantages that
are possible, with the exception of engine weight reduction.
[0052] It is also another object of present invention to make it
possible to design diesel fueled reciprocating internal combustion
engines that weigh less for a given power output. Engine weight in
new diesel engines designed and produced with the present invention
incorporated into them can be designed to weigh much less for a
given power output.
[0053] This is possible as a result of the lower peak combustion
chamber pressures that occur in a reciprocating direct injected
internal combustion engine, such as a diesel engine, that has the
present invention incorporated into it. Diesel engines currently
being manufactured have to be designed to deal with very high peak
pressures inside of the combustion chamber that are necessary for
heat-of-compression ignition to work. These very high peak
pressures are also responsible for the creation of NOx. Because
lower peak pressures inside the combustion chamber will occur in a
diesel engine equipped with the present invention, the engine block
will be subjected to lower peak stresses making it possible to
design the engine to weigh less for a given engine displacement and
power output.
[0054] These objects of the present invention are accomplished by
creating an area of electrical ionization in front of or in close
proximity to the nozzles of the fuel injectors. When fuel is
injected into the combustion chamber, it must pass through or next
to this area of electrical ionization. By having this take place,
combustion is initiated for all of the injected fuel as it enters
the combustion chamber of any kind of internal combustion engine.
This area of electrical ionization will be maintained as long as
necessary to sustain the combustion process. In the case of gas
turbines, the Ring-of-Fire will be kept on continuously until the
engine has warmed up to the point that the engine has reached an
operating temperature at which combustion will be maintained on its
own. When used in the combustion chamber of reciprocating type
engines, the Ring-of-Fire will be kept going during the power
stroke until the combustion process has been completed.
[0055] To do this, there are a number of electrodes placed so that
their tips define a polygon inside the combustion chamber that is
in front of the nozzle of the fuel injector. When this polygon
defined by the electrode tips is energized electrically, it creates
an area of electrical ionization also called the Ring-of-Fire. This
Ring-of-Fire will ionize anything inside of it or in close
proximity to it. For a pintle type fuel injector, the spray pattern
of the fuel being injected into the combustion chamber will for the
most part, pass through the area of electrical ionization defined
by the polygon between the electrode tips. For a hole type fuel
injector, the spray pattern of the fuel being injected is in such
close proximity to the Ring-of-Fire that the fuel entering the
combustion chamber will be ignited by this Ring-of-Fire.
[0056] These electrodes are held in position by a ceramic sleeve
that surrounds the barrel of the fuel injector and extends from the
combustion chamber through the cylinder head with the electrode
wires embedded inside it. The other end of the wires that are
embedded in the ceramic sleeve are connected to a set of spark plug
type high voltage wires that are in turn connected to a high
voltage electrical discharge source. There are a wide variety of
high voltage electrical discharge sources that could be used by
having them integrated into the circuitry that creates the
Ring-of-Fire.
[0057] R. S. Warner developed a system that could be easily
integrated into the Ring-of-Fire high voltage electrical discharge
circuitry. This system was known as the Pulse-Tronic 1000 ignition
unit and R. S. Warner presented a research paper about it to the
Diesel & Gas Engine Power Division of the American Society of
Mechanical Engineers during the ASME Diesel & Gas Engine Power
Conference and Exhibit held in Dallas, Tex. in April, 1970.
[0058] An interesting feature of this system is its output of a
train of pulses used to initiate and maintain the combustion
process inside the combustion chamber. The Pulse-Tronic 1000
ignition unit was shown to be capable of successfully burning fuel
air mixtures that were much leaner than what could be ignited by
conventional ignition systems. Lean fuel air mixtures are
notoriously hard to ignite and keep burning and the fact that this
unit could successfully do so indicates the general superiority of
this ignition system.
[0059] Although applied only to gasoline engines, this system may
be used as the high voltage electrical discharge source for the
Ring-of-Fire circuit in the present invention. The Pulse-Tronic
1000 ignition unit is self-contained and powered by mechanical
energy from the motor via a fan belt or rotating shaft without the
need of a connection to a battery or other electrical power
source.
[0060] Rich (U.S. Pat. No. 5,429,103) also discloses a means of
producing a high voltage output with a waveform almost the same as
the Pulse-Tronic 1000 ignition unit developed by R. S. Warner. The
Rich patent high performance ignition system is able to initiate
and maintain combustion of lean fuel air mixtures that are
difficult to burn in engines that were equipped with it.
[0061] The high voltage electrical discharge circuitry that is used
in the preferred embodiment as realized in the operational
prototype creates a ball of plasma located directly in front of the
nozzle of the fuel injector. This ball of plasma is remarkably
effective at insuring complete combustion of all of the fuel
injected through it.
[0062] None of the examples disclosed in the prior art propose a
means of creating an area of thorough electrical ionization in the
combustion chamber and locating it so that all of the fuel being
injected into the combustion chamber must pass in close proximity
or through the area of electrical ionization.
[0063] In the case of the present invention being applied to diesel
engines, eliminating the dependency of the engine upon the heat of
compression for the initiation and maintenance of the combustion
process makes it is possible to achieve real-time control of the
complete combustion process. This gives the engine designer
unprecedented flexibility in tuning the engine to achieve what is
needed for any given application, be it fuel economy, power, or low
pollutant emissions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] The above and other objects and features of the present
invention will be clearly understood from the following description
with respect to the preferred embodiment thereof when considered in
conjunction with the accompanying drawings and diagrams, in
which:
[0065] FIG. 1 is a cross sectional side view of the
injector/igniter apparatus of the present invention installed in an
engine cylinder head.
[0066] FIG. 2 is a cross sectional side view of the
injector/igniter apparatus of the present invention installed in an
engine cylinder head with fuel being injected into the combustion
chamber.
[0067] FIG. 3A is an enlarged side view of the lower end of the
injector/igniter apparatus that extends through the cylinder
head.
[0068] FIG. 3B is an enlarged bottom view of the injector/igniter
apparatus.
[0069] FIG. 3C is an enlarged side view of the injector/igniter
apparatus rotated by 90 degrees from the view presented in FIG.
3A.
[0070] FIG. 3D is an enlarged perspective view of the
injector/igniter apparatus.
[0071] FIG. 4A is an enlarged side view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation.
[0072] FIG. 4B is an enlarged bottom view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation.
[0073] FIG. 4C is an enlarged side view of the injector/igniter
apparatus rotated by 90 degrees from the view presented in FIG.
4A.
[0074] FIG. 4D is an enlarged perspective view of the
injector/igniter apparatus with the Ring-of-Fire shown in
operation.
[0075] FIG. 5A is an enlarged side view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation and with fuel
being injected by a pintle type of fuel injector.
[0076] FIG. 5B is an enlarged bottom view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation and with fuel
being injected by a pintle type of fuel injector.
[0077] FIG. 5C is an enlarged side view of the injector/igniter
apparatus rotated by 90 degrees from the view presented in FIG. 5A
with the Ring-of-Fire shown in operation and with fuel being
injected by a pintle type of fuel injector.
[0078] FIG. 5D is an enlarged perspective view of the
injector/igniter apparatus with the Ring-of-Fire shown in operation
and with fuel being injected by a pintle type of fuel injector.
[0079] FIG. 6A is an enlarged side view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation and with fuel
being injected by a hole type of fuel injector.
[0080] FIG. 6B is an enlarged bottom view of the injector/igniter
apparatus with the Ring-of-Fire shown in operation and with fuel
being injected by a hole type of fuel injector.
[0081] FIG. 6C is an enlarged side view of the injector/igniter
apparatus rotated by 90 degrees from the view presented in FIG. 6A
with the Ring-of-Fire shown in operation and with fuel being
injected by a hole type of fuel injector.
[0082] FIG. 6D is an enlarged perspective view of the
injector/igniter apparatus with the Ring-of-Fire shown in operation
and with fuel being injected by a hole type of fuel injector.
[0083] FIG. 7A is a cross sectional side view of the
injector/igniter apparatus of the present invention.
[0084] FIG. 7B is a top view of the injector/igniter apparatus of
the present invention.
[0085] FIG. 7C is a bottom view of the injector/igniter apparatus
of the present invention.
[0086] FIG. 8A is a cross sectional side view of the ceramic sleeve
portion of the injector/igniter apparatus of the present
invention.
[0087] FIG. 8B is a top view of the ceramic sleeve portion of the
injector/igniter apparatus of the present invention.
[0088] FIG. 8C is a bottom view drawing of the ceramic sleeve
portion of the injector/igniter apparatus of the present
invention.
[0089] FIG. 9 is a block diagram of the signal generation circuit
portion of the present invention.
[0090] FIG. 10A is a timing signal diagram of the square-wave
signal created by the square-wave generator in the signal
generation circuit of the present invention.
[0091] FIG. 10B is a timing signal diagram of the six sequential
signals created by the signal divider circuit in the signal
generation circuit of the present invention.
[0092] FIG. 10C is a timing signal diagram of the six overlapped
sequential signals created by the signal overlap circuit in the
signal generation circuit of the present invention.
[0093] FIG. 11 is a schematic of one of the high voltage discharge
circuits of the present invention.
[0094] FIG. 12 is a diagram depicting all six high voltage
discharge circuits attached to the ceramic sleeve portion of the
injector/igniter apparatus of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0095] The invention will now be described in further detail in
connection with illustrative preferred embodiments for improving
combustion in a direct injected internal combustion engine enabling
the engine to achieve better fuel economy, reduced pollutant
emissions, and more power. Within the scope of the present
invention, this system could be applied to gas turbines and to
reciprocating internal combustion engines that are direct injected
of either the 2-stroke or the 4-stroke type that have been designed
for use with any type of combustible fuel including gasoline,
diesel or jet fuel.
[0096] Referring to FIG. 1, the present invention is shown mounted
in a cylinder head 15 of a diesel engine. An engine block 11 has
placed inside it a piston 13 and mounted on top of the engine block
11 is the cylinder head 15. A combustion chamber 17 is located
inside the area surrounded by the engine block 11, the piston 13,
and the cylinder head 15. Passing through the cylinder head 15 is a
fuel injector 21 that has its lower body surrounded by a ceramic
sleeve 23. A fuel inlet 25 attached to the upper portion of the
fuel injector 21 has a fuel passageway 19 that allows fuel to
travel to a fuel injection nozzle 27. This fuel injection nozzle 27
protrudes into the inside of the combustion chamber 17.
[0097] A plurality of embedded wires 29 travel from high voltage
terminals 31 mounted on the ceramic sleeve 23 outside and above the
cylinder head 15 through the length of the ceramic sleeve 23
including substantially parallel to the lower portion of the fuel
injector 21. These embedded wires 29 extend into the combustion
chamber 17 as electrodes 33. In this embodiment, there are six
electrodes 33 arrayed around and below the fuel injector nozzle 27
inside the combustion chamber 17. All six electrodes 33 are
individually connected to high voltage terminals 31 by their own
embedded wire 29.
[0098] Referring to FIG. 2, pressurized fuel is shown entering the
fuel injector 21 through the fuel inlet 25, down fuel passageway
19, and then out of the fuel injector nozzle 27 into the combustion
chamber 17 producing a fuel injection spray pattern 37. While this
is happening, a high voltage discharge 35 occurs between all of the
tips of the six electrodes 33 inside the combustion chamber 17,
with the fuel injection spray pattern 37 passing right next to, or
through the high voltage discharge 35. The power for the high
voltage discharge 35 that occurs between the six electrodes 33 is
produced by a set of six high voltage discharge circuits 51, 53,
55, 57, 59 and 61 (discussed in detail with reference to FIGS. 11
and 12).
[0099] A set of six spark plug type high voltage wires 39, 41, 43,
45, 47 and 49 connects on one end to the set of six high voltage
discharge circuits 51, 53, 55, 57, 59 and 61. The other end of the
set of six spark plug type high voltage wires 39, 41, 43, 45, 47
and 49 have an externally insulated connector 32 that secures and
protects the connection to the six high voltage terminals 31
mounted on the upper portion of the ceramic sleeve 23. This set of
six high voltage discharge circuits 51, 53, 55, 57, 59 and 61 is
controlled by a signal generation circuit 63 which has its position
in the system discussed in connection with FIG. 12 and has its
operation discussed in detail in connection with FIG. 9.
[0100] FIG. 3A is a side view of the lower portion of the ceramic
sleeve 23 that extends through the cylinder head 15 into the
combustion chamber 17. The fuel injection nozzle 27 at the end of
the fuel injector 21 and electrodes 33 are on the end of the
ceramic sleeve 23 that faces into the combustion chamber 17.
[0101] FIG. 3B shows the only part of the present invention that is
actually exposed to the inside of the combustion chamber 17. The
six electrodes 33 are arranged in a circular manner around the fuel
injection nozzle 27.
[0102] FIG. 3C shows the same piece of the present invention that
is illustrated by FIG. 3A with the difference being that the image
was rotated by 90 degrees in order to clarify the shape and
position of the electrodes 33 on the end of the ceramic sleeve
23.
[0103] An oblique perspective of the lower portion of the ceramic
sleeve 23 further illustrates the placement relationship of the
fuel injector nozzle 27 to the electrodes 33 in FIG. 3D.
[0104] FIGS. 4A, 4B and 4C provide the same set of views as FIGS.
3A, 3B and 3C the inclusion of the operation of the high voltage
discharge 35. This gives further clarification of the placement of
the high voltage discharge 35 upon the electrodes 33 that are
arrayed around the fuel injector nozzle 27 on the end of the
ceramic sleeve 23 that faces the combustion chamber 17. This
combustion chamber 17 could, within the scope of the present
invention, be installed in any of a variety of engine types to
include gas turbines as well as reciprocating 2-cycle and 4-cycle
diesel or gasoline direct injected internal combustion engines.
[0105] FIG. 4D also shows the same oblique perspective view of the
lower portion of the ceramic sleeve 23 as shown in FIG. 3D with the
inclusion of the high voltage discharge 35 occurring between the
six electrodes 33. Other numbers of electrodes to create the
Ring-of-Fire are possible. Also, the Ring-of-Fire is schematically
illustrated in these figures since it is difficult to illustrate
completely.
[0106] FIGS. 5A, 5B, 5C and 5D show the lower portion of the
ceramic sleeve 23 as shown in FIGS. 4A, 4B, 4C and 4D with the
inclusion of fuel being injected by a fuel injector 21. The fuel
injection spray pattern 37 of a pintle type of the fuel injector
nozzle 27 places a cone of injected fuel centered to the high
voltage discharge 35 that occurs between the electrodes 33 inside
the combustion chamber 17. This insures complete combustion
initiation of all of the fuel as it is injected.
[0107] FIGS. 6A, 6B, 6C and 6D show the lower portion of the
ceramic sleeve 23 as shown in FIGS. 5A, 5B, 5C and 5D. The
difference is that this time the fuel injector 21 has a fuel
injector nozzle 27 of the hole type. The hole type fuel injector
nozzle 27 produces a fuel injection spray pattern 37 that has a set
of lobes. Each lobe sprays directly next to or through the high
voltage discharge 35 thus insuring complete combustion initiation
of all of the fuel as it is injected into the combustion chamber
17.
[0108] Referring to FIG. 7A, the fuel injector 21 is installed
inside the ceramic sleeve 23. When fuel injection is taking place,
a fuel injector pump (not shown) sends pressurized fuel to the fuel
inlet 25 of the fuel injector 21 in a manner known in the art. The
pressurized fuel travels through fuel passageway 19 to the fuel
injector nozzle 27 that injects the fuel into the combustion
chamber 17. The ceramic sleeve 23 surrounds the lower portion of
the fuel injector 21.
[0109] The upper end of the ceramic sleeve 23 that is above the
cylinder head 15 has six high voltage terminals 31 that are
connected to six embedded wires 29 that extend from the top to the
bottom of the ceramic sleeve 23. The lower ends of the six embedded
wires 29 extend from the bottom of the ceramic sleeve 23 into the
combustion chamber 17 as six electrodes 33. These six electrodes 33
are positioned such that their tips are arranged so that they
define a hexagon inside the combustion chamber 17 around and below
the fuel injector nozzle 27. This placement is important to insure
that the fuel injection spray pattern 37 from the fuel injector
nozzle 27 must pass in close proximity to or through the high
voltage discharge 35 that occurs between the tips of the electrodes
33.
[0110] FIG. 7B shows a top view of the fuel injector 21 mounted
through the ceramic sleeve 23 with the placement of the six high
voltage terminals 31 clearly shown.
[0111] FIG. 7C is a view from the combustion chamber 17 looking up
at the face of the ceramic sleeve 23 and at the tip of the fuel
injector 21 with the fuel injection nozzle 27 in the center of the
six electrodes 33.
[0112] FIGS. 8A, 8B and 8C are similar views as FIGS. 7A, 7B and 7C
without the fuel injector 21 being shown to further clarify the
positions of the high voltage terminals 31, the embedded wires 29
and the electrodes 33.
[0113] FIG. 9 shows the signal generation circuit 63 in detail. The
signal generation circuit 63 controls the high voltage generation
circuits 51, 52, 53, 55, 57, 59 and 61. The signals mentioned in
this discussion are shown in detail by FIGS. 10A, 10B and 10C.
[0114] The signal generation circuit 63 has its overall output
controlled by an engine timing signal source 65 that turns it on
and off through an engine timing signal transmission line 67. The
engine timing signal source 65 controls the signal generation
circuit 63 so that at the appropriate time, at or before fuel
injection is to take place, the high voltage discharge 35 is
initiated. The engine timing signal source 65 keeps the high
voltage discharge 35 going for as long as necessary to ensure
complete combustion of all of the fuel and air mixture inside the
combustion chamber 17.
[0115] The signal generation circuit 63 has within it a square-wave
generator circuit 69 that sends through a square-wave signal
transmission line 71, a square-wave signal 73 to a signal divider
circuit 75. The square-wave generator circuit 63 is based on a 555
timer integrated circuit set up to operate as an astable
multi-vibrator circuit producing a square-wave signal between 0 and
5 volts at a frequency between 5 and 30 kilohertz.
[0116] The signal divider circuit 75 divides the square-wave signal
73 into a set of six sequential signals 89, 91, 93, 95, 97 and 99,
as shown in FIG. 10B, that are sent through a set of six sequential
signal transmission lines 77, 79, 81, 83, 85 and 87 to a signal
overlap circuit 101. The signal divider circuit 75 that divides the
square-wave signal 73 into a set of six sequential signals 89, 91,
93, 95, 97 and 99 is based on the 4017 decade counter integrated
circuit.
[0117] The signal overlap circuit 101 in turn generates a set of
six overlapped sequential signals 115, 117, 119, 121, 123 and 125,
as shown in FIG. 10C, and then sends these signals through a set of
six overlapped sequential signal lines 103, 105, 107, 109, 111 and
113 to a signal line driver circuit 127. The signal overlap circuit
101 uses a bank of twelve 1N4004 diodes to generate the set of six
overlapped sequential signals 115, 117, 119, 121, 123 and 125 shown
in FIG. 10C.
[0118] The signal line driver circuit 127 is activated only when
the enable signal from the engine timing signal source 65, brought
in by the engine timing signal transmission line 67 and it allows
the set of six overlapped sequential signals 115, 117, 119, 121,
123 and 125 to go through the signal line driver circuit 127. The
signal line driver circuit 127 uses a 74HCT541 integrated circuit
to act as a "gate" to the set of six overlapped sequential signals
115, 117, 119, 121, 123 and 125.
[0119] It is within the scope of the present invention to have this
engine timing signal source 65 be as simple as a cam-shaft position
sensor, such as a Hall-effect sensor, or as complicated as a highly
sophisticated engine management computer responding in real time to
a number of factors to include actual conditions inside of the
combustion chamber 17 as they happen in real time as is known in
the art. When enabled by the engine timing signal source 65, the
signal line driver circuit 127 then "cleans up" and strengthens the
set of six overlapped sequential signals 115, 117, 119, 121, 123
and 125 without otherwise changing them before they are sent out
through a set of six control signal output lines 129, 131, 133,
135, 137 and 139 to each of the six high voltage discharge circuits
51, 53, 55, 57, 59 and 61.
[0120] FIG. 11 is an electrical schematic for each high voltage
discharge circuit 51, 53, 55, 57, 59 and 61. Each of the six high
voltage discharge circuits 51, 53, 55, 57, 59 and 61 is connected
to a 24 volt power source 143 and to one of the six control signal
output lines 129, 131, 133, 135, 137 and 139. When a signal is
received by its intended high voltage discharge circuit 51, 53, 55,
57, 59 and 61 it turns on a power MOSFET 145 labeled Q-1. In one
embodiment of the present invention, the power MOSFET (Metal Oxide
Surface Effect Transistor) 145 labeled Q-1 is a MTY55N20E made by
Motorola and it is rated for 55 amps at 200 volts.
[0121] When the power MOSFET 145 labeled Q-1 is turned on, a high
voltage transformer 147 labeled T-1 then has current flow from the
24 volt power source 143 through a primary winding power lead 149.
The current passes through a primary winding 151 of the high
voltage transformer 147 labeled T-1, through a primary winding
ground lead 153, through the power MOSFET 145 labeled Q-1, through
a resistor 155 labeled R-1 that is rated at 0.2 ohms and 10 watts,
and then finally to a low voltage ground connection 157. This low
voltage ground connection 157 is shared by all of the six high
voltage discharge circuits 51, 53, 55, 57, 59 and 61 and it is also
used by all of the components of the signal generation circuit 63.
There is a large value capacitor 159 labeled C-1 which is rated at
1 microfarad and a small value capacitor 161 labeled C-2 which is
rated at 0.01 microfarads. Both are attached in parallel across the
primary winding power lead 149 and the primary winding ground lead
153.
[0122] An electrically isolated secondary winding 163 of the high
voltage transformer 147 labeled T-1 has an electrically isolated
secondary winding ground lead 165 connected to an electrically
isolated "floating" high voltage ground 167 that is shared in the
same position of each circuit in all of the six high voltage
discharge circuits 51, 53, 55, 57, 59 and 61. The electrically
isolated secondary winding 163 of the high voltage transformer 147
labeled T-1 is connected to an electrically isolated secondary
winding high voltage output lead 169. The electrically isolated
secondary winding high voltage output lead 169 is in turn connected
to the appropriate one of the set of six spark plug type high
voltage wires 39, 41, 43, 45, 47 and 49 which in turn are connected
to one of the set of six high voltage terminals 31 on the ceramic
sleeve 23.
[0123] FIG. 12 shows the overall combination of elements of the
electrical system according to the present invention. This includes
a 5 volt power source 171 used by all of the circuitry inside the
signal generation circuit 63. Further a low voltage ground
connection 157 is shown as being shared by all of the high voltage
discharge circuits 51, 53, 55, 57, 59 and 61 and with the signal
generation circuit 63.
[0124] It should be appreciated that the other ways of creating and
controlling the Ring-of-Fire high voltage discharge 35. Although
any means of creating and controlling the Ring-of-Fire must place
it so that the injected fuel spray pattern 37 go next to or through
it as fuel enters the combustion chamber 17.
* * * * *