Apparatus for introducing combustion supporting particles to an internal combustion engine

A simple, inexpensive apparatus for introducing a mixture of vaporized fuel, air and combustion supporting particles to an internal combustion engine to improve combustion efficiency and to reduce emissions of incompletely combusted hydrocarbon fuels is provided. The apparatus includes a single chamber for containing a volume of liquid fuel and a volume of vaporized fuel, a supply of combustion supporting particles disposed within the chamber, a conduit for supplying liquid fuel to the chamber, a conduit for supplying air to the chamber, a liquid level controller for maintaining the volume of liquid fuel in the chamber within predetermined limits, and an outlet from the chamber for conveying a mixture of vaporized fuel, air and combustion supporting particles to a vacuum inlet of an internal combustion engine. The disclosed apparatus is utilized in a combination including an internal combustion engine and a fuel system therefor, to improve the fuel economy of motor driven vehicles.

FIELD OF THE INVENTION 
This invention relates to an apparatus for entraining combustion supporting 
particles in a mixture of vaporized fuel and air, and introducing the 
resulting mixture of vaporized fuel, air and entrained combustion 
supporting particles into a combustion chamber of an internal combustion 
engine. 
BACKGROUND OF THE INVENTION 
It is well known that internal combustion engines do not combust all of the 
fuel which is introduced to the combustion chambers thereof. Although 
pollution problems associated with the incomplete combustion of fuel in 
internal combustion engines has been successfully overcome by introducing 
the exhaust gases from the combustion chamber or chambers of the internal 
combustion engine to a catalytic convertor, there has only been relatively 
modest improvements in the combustion efficiency and hence fuel economy of 
internal combustion engines. Prior attempts to improve the combustion 
efficiency of internal combustion engines have generally either involved 
extensive modifications which were impractical because of the increased 
complexity and expense of manufacturing and maintaining the engine, or 
they have involved the use of simpler devices which have only provided a 
relatively modest improvement in fuel efficiency. 
In U.S. Pat. No. 5,002,033, issued on Mar. 26, 1991, I disclosed a 
relatively simple apparatus for improving combustion efficiency, reducing 
hydrocarbon emissions, and providing improved fuel economy. The apparatus 
is used for preparing and supplying a mixture of fuel, air and combustion 
supporting particles to an internal combustion engine, whereby fuel is 
more efficiently combusted. The apparatus includes a first chamber for 
preparing a mixture of vaporized fuel and air, and a second chamber for 
preparing a mixture of vaporized fuel, air and combustion supporting 
particles. The output from the two chambers are mixed and introduced to 
the combustion chamber or chambers of an internal combustion engine. The 
apparatus utilizes at least one ultrasonic transducer for applying energy 
to the fuel in the major chamber for causing a portion of the fuel to 
vaporize and mix with air in the major chamber. The use of ultrasonic 
transducers in the apparatus introduces a number of complications. For 
example, effective utilization of the ultrasonic transducers requires that 
the ultrasonic transducers be mounted in the bottom wall of the major 
chamber in immediate fluid contact with the fuel in the chamber, thus 
requiring the use of sealing materials to prevent gasoline from escaping 
from around the transducers. It has also been found that it is relatively 
difficult to provide an inexpensive chamber which is suitable for the 
environment in which the apparatus will be utilized, and which is capable 
of withstanding the vibrations of the ultrasonic transducer for a 
prolonged period of time. Further, the apparatus disclosed in U.S. Pat. 
No. 5,002,033 utilizes an auxiliary fuel pump for supplying fuel to the 
major chamber. Thus, while the disclosed apparatus achieves improved 
combustion efficiency, e.g. as much as 50% or more, it would be desirable 
to provide a simpler apparatus which achieves comparable results. 
SUMMARY OF THE INVENTION 
It is an object of this invention to provide a simple, inexpensive 
apparatus for introducing a mixture of vaporized fuel, air and combustion 
supporting particles to an internal combustion engine to improve 
combustion efficiency, reduce emissions of incompletely combusted 
hydrocarbon fuels, and thus provide improved fuel economy, while 
facilitating easy installation and maintenance of the apparatus. 
Specifically, it an object of this invention to provide a simplified 
apparatus which utilizes only a single chamber for volatilizing a liquid 
hydrocarbon fuel, mixing the volatilized hydrocarbon fuel with air, and 
entraining combustion supporting particles in the mixture of volatilized 
fuel and air. It is a further object of the invention to achieve the 
foregoing results without employing ultrasonic transducers or other 
electrically powered means for vaporizing the liquid hydrocarbon fuel, and 
to eliminate the need for an auxiliary fuel pump. 
It has been found that the foregoing objects can be achieved by employing a 
simplified apparatus for introducing combustion supporting particles to an 
internal combustion engine, which comprises a single chamber for 
containing a volume of liquid fuel and a volume of vaporized fuel, a 
supply of combustion supporting particles disposed within the chamber, a 
conduit for supplying liquid fuel to the chamber, a conduit for supplying 
air to the chamber, a liquid level controller for maintaining the volume 
of liquid fuel in the chamber within predetermined limits, and an outlet 
from the chamber for conveying a mixture of vaporized fuel, air and 
combustion supporting particles to a vacuum inlet of an internal 
combustion engine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Shown in FIGS. 1 and 2 is an improved apparatus 10 for introducing 
combustion supporting particles to an internal combustion engine. The 
apparatus includes a single chamber 20 having a lower portion 22 for 
containing a volume of liquid fuel 24 and an upper portion 26 for 
containing a volume of vaporized fuel, air and entrained combustion 
supporting particles. Chamber 20 is generally defined by a housing 28 
having a removable lid 30. In the illustrated embodiment, housing 28 has a 
generally cylindrical shape with a lower section which, on the exterior 
side, has a truncated conical shape, and which is conically shaped on the 
interior. A supply of combustion supporting particles 32 is disposed 
within the lower portion 22 of chamber 20. A first conduit 34 supplies 
liquid fuel to the chamber 20. A second conduit 36 supplies atmospheric 
air to the chamber 20. The outlets for conduits 34 and 36 are disposed 
near the bottom of chamber 20 so that both liquid fuel and air are 
introduced into chamber 20 below a lower limit of the liquid level of the 
chamber. More specifically, the air conduit 36 introduces air into the 
chamber near the bottom of the chamber below a predetermined lower limit 
for the liquid fuel level. Likewise, the liquid fuel conduit introduces 
liquid fuel into the chamber near the bottom of the chamber below the 
predetermined lower limit for the liquid fuel level. A liquid level 
detector/controller 38 is positioned near the lower portion 22 of chamber 
20 to detect the level of liquid fuel in the chamber and to operate a 
valve which diverts a small portion of the liquid fuel being supplied to 
an engine to chamber 20 when the liquid level in chamber 20 drops below a 
predetermined lower limit. Detector/controller also operates to close the 
valve when the liquid level in the chamber rises above a predetermined 
upper limit to prevent additional liquid fuel from entering the chamber. 
In the illustrated embodiment, the liquid level detector/controller 38 is 
a relatively simple commercially available float device which includes a 
vertical guide rod 40, a generally cylindrical shaped float 42 having a 
vertical through-bore through which guide rod 40 extends, and internal 
magnetically sensitive switching means which respond to magnetic material 
located near the upper and lower sides of float 42. Generally, any of 
various suitable liquid level detector/controller devices may be employed 
for detecting and controlling the liquid fuel level in chamber 20. Such 
devices are well known and will not be described in detail herein. 
Apparatus 10 also includes an outlet 44 from chamber 20 for conveying a 
mixture of vaporized fuel, air and combustion supporting particles to a 
vacuum inlet of an internal combustion engine. 
A suitable chamber volume is from about 0.5 liters to about 5 liters, and 
more preferably from about 1 liter to about 2 liters. Housing 28 can be 
made of any suitable material, such as steel, copper, aluminum or plastic. 
Likewise, removable lid 30 can be made of any suitable material such as 
steel, copper, aluminum, brass or plastic. As shown in the illustrated 
embodiment, lid 30 is provided with a threaded port 85 which is closed by 
a threaded plug 87. Port 85 allows the supply of combustion supporting 
particles to be replenished as needed. Housing 28 is preferably provided 
with a flange 46 having a plurality of threaded apertures, and a plurality 
of corresponding apertures are provided near the periphery of lid 30 to 
allow securement of lid 30 to flange 46 with threaded fasteners 48. Liquid 
fuel conduit 34, air conduit 36 and outlet 44 can be made of any suitable 
material, such as stainless steel or copper tubing. Unlike conduits 34 and 
36, the inlet opening of outlet port 44 is located near lid 30, i.e. is 
disposed about as far as possible from the liquid fuel to minimize the 
possibility of introducing entrained liquid droplets into the outlet 44. 
By contrast, the outlets of conduits 34 and 36 are located below the 
predetermined lower limit for the liquid fuel level so that air and fuel 
are introduced to chamber 20 within the volume occupied by the liquid 
fuel. 
Air conduit 36 is preferably provided with a metering aperture having a 
diameter of from about 0.4 to abut 0.8 millimeters. It may also be 
desirable to provide an inlet filter on the air conduit 36 to prevent 
unwanted particulate matter from entering chamber 20. 
The illustrated embodiment includes a shroud 50 which generally surrounds 
float 42 to prevent the float from being influenced by rapid fluctuations 
in the pressure of a vacuum inlet of an internal combustion engine which 
is in communication with chamber 20 through outlet 44. Such rapid 
fluctuations could cause erroneous liquid level readings by the 
detector/controller, which could cause under- or over-filling of the 
chamber with liquid fuel. Shroud 50 includes a plurality of apertures 52 
which are disposed above the predetermined upper limit for the liquid fuel 
level to allow equalization of pressure on both sides of the shroud, and a 
plurality of rectangular openings or slots 54 disposed below the 
predetermined lower limit of the liquid fuel level to allow equalization 
of the liquid level on both sides of the shroud. 
The preferred particulate material for use in the fuel system of the 
present invention is powdered aluminum which is available from the 
Aldridge Chemical Company in Wisconsin. The aluminum powder is preferably 
of a size which is sufficiently small to avoid any deleterious effect on 
the operation of an internal combustion engine. Suitable particles sizes 
range from about 9 microns to about 20 microns. Although larger or smaller 
particle sizes may be employed, it is believed that appreciable benefits 
are not realized by utilizing particles smaller than about 9 microns and 
that particles significantly larger than 20 microns may have an 
undesirable effect on engine performance. Other metals have been tried in 
the fuel system with varying degrees of success. For example, powdered 
palladium metal has been found to produce slightly better results than 
powdered aluminum. However, powdered aluminum is substantially less 
expensive than powdered palladium, and is therefore preferred. The fuel 
system of this invention would also be expected to work with other 
powdered metals, such as copper, brass, bronze, and even with non-metallic 
materials which can heat rapidly in a combustion chamber of an internal 
combustion engine. The particulate material can also be a mixture of 
different particulate materials. The particular additive to be used in the 
fuel system can be determined through experimentation. As suggested above, 
aluminum powder having a particle size of from about 9 microns to about 20 
microns have been found to produce very good results and are preferred in 
view of their ready availability, lower expense and ease of handling. 
Experimental data indicate that approximately 6 ounces of aluminum powder 
will provide approximately 20,000 miles of improved engine performance. 
A fuel system for an internal combustion engine utilizing the above 
described apparatus for introducing combustion supporting particles to an 
internal combustion engine is shown schematically in FIG. 2. Fuel system 
60 includes a fuel tank 62 which can be of conventional design, a fuel 
pump 64, which may also be of conventional design, apparatus 10, and 
internal combustion engine 66. A portion of the fuel being supplied to 
engine 66 by pump 64 through fuel line 68 can, as needed, be diverted to 
apparatus 10 through fuel line 70 when valve 72 is open. Liquid fuel 
conduit 34 of apparatus 10 is in fluid communication with fuel line 70. 
The mixture of vaporized fuel, air and combustion supporting particles 
generated in apparatus 10 leaves chamber 20 through outlet 44 and is 
conveyed to internal combustion engine 66 through conduit 74. Conduit 74 
is preferably provided with a check valve 75 having approximately a 5 
pound pressure which protects the fuel system from the high vacuum that 
exists at idle or under throttled down conditions. The mixture of 
vaporized fuel, air and entrained combustion supporting particles 
generated by apparatus 10 are introduced into internal combustion engine 
66 at an appropriate point, such as down stream of the fuel injectors of a 
fuel injected engine or to the PCV input below the fuel jets and butterfly 
valve of a carburetor of a carbureted internal combustion engine. 
Apparatus 10 can be utilized with generally any type of internal 
combustion engine and is generally compatible with any type of fuel 
system. 
In operation, the liquid level in chamber 20 is monitored and controlled by 
liquid level detector/controller 38. Specifically, the liquid level is 
maintained such that the combustion supporting particles 32 at the bottom 
of chamber 20, and the outlets of conduits 34 and 36 are always submerged 
in liquid fuel. More specifically, detector/controller 38 operates control 
valve 72 to allow liquid fuel to enter chamber 20 through conduit 34 when 
the liquid level in chamber 20 reaches a predetermined lower limit, and 
closes valve 72 when the liquid fuel reaches a predetermined upper limit. 
As previously stated, the major criterion for selecting the predetermined 
lower limit for the liquid fuel level is maintenance of a liquid level 
which ensures that air and fuel are introduced into the volume of chamber 
20 occupied by the liquid fuel. The predetermined upper limit for the 
liquid fuel level is not critical. However, various factors, such as the 
frequency at which valve 72 is opened and closed, the total volume of the 
chamber 20, and the relative proportion of liquid volume and vapor volume, 
should be taken into consideration. With the illustrated embodiment, a 
suitable lower limit for the liquid level can be about 2 inches, and a 
suitable upper limit for the liquid level can be about 3 inches. The 
outlets of air conduit 36 and liquid fuel conduit 34 are preferably 
located at least about 0.5 inches below the predetermined lower limit for 
the liquid fuel level. 
It has been found that by bubbling atmospheric air through the liquid fuel 
and combustion supporting particles 32 in a chamber having a relatively 
small proportion of its volume containing liquid fuel and combustion 
supporting particles, and a major portion of its volume containing 
vaporized fuel, it is possible to generate a suitable mixture of vaporized 
fuel, air and combustion supporting particles which can be introduced into 
an internal combustion engine to improve the combustion efficiency 
thereof. As with my previous invention disclosed in U.S. Pat. No. 
5,002,033, the mixture of vaporized fuel, air and combustion supporting 
particles generated by apparatus 10 comprises only a small portion of the 
total amount of fuel and air which is introduced into the combustion 
chambers of an internal combustion engine. The relatively small volume of 
fuel which is diverted from fuel line 68 to apparatus 10 does not require 
any modification of the fuel pump 64 or any significant modification of 
engine 66. Additionally, the apparatus 10 is relatively small, e.g. 
generally occupying from about 1 to 2 liters of volume, such that it is 
generally possible to easily add apparatus 10 to an existing fuel system 
for an internal combustion engine. For example, the apparatus can be 
easily retrofitted into existing motor vehicles, such as automobiles, 
trucks, boats, etc. As with my previous invention (U.S. Pat. No. 
5,002,033) the mixture of fuel, air and combustion supporting particles 
can be passed through conduit 74 to heat exchanger 76 to maintain the fuel 
in a vaporized state. Heat exchanger 76 can be heated with fluid from the 
engine block, or with exhaust gases. It is anticipated that the apparatus 
10 can improve fuel economy by as much as 50% or more. 
Though the invention has been described with respect to a specific 
preferred embodiment thereof, many variations and modifications will 
become apparent to those skilled in the art. It is therefore the intention 
that the appendant claims be interpreted as broadly as possible in view of 
the prior art to include all such variations and modifications.