US3685808A - Means of preparing a fuel-air mixture - Google Patents

Abstract

A means and method wherein a portion of an air supply is diverted, subject to intense turbulence, then injected into a fuel supply to create a turbulent fuel-air premixture which is immediately introduced into the air supply. Further included in some embodiments is a means of producing mechanical vibration in parts located in the region wherein premixing occurs, and in the region wherein introduction of the premixture into the main air supply occurs.

Description

United States Patent 1151 3,685,808 Bodai 14 1 Aug. 22,1972

[ MEANS OF PREPARING A FUELeAlR 2,014,907 9/1935 Myers ..261/79 R MIXTURE 2,273,979 2/1942 Mock ..261/1 3,539,157 11/1970 Fort .;....26l/DlG. 69 [72] Invent 3,519,407 7/1970 Hilbom .,..261/D1G. 39 [73] Assignee: Technoscience Systems, Inc., La

p m C l ii FOREIGN PATENTS OR APPLICATIONS 22 i July 23 1970 389,785 6/1921 Germany ..261/79 R [21] Appl 57,524 Primary ExaminerTim R. Miles Attorney-Lyon & Lyon [52] US. Cl. ..261/1, 261/79 R, 261/121 A,

261/D1G. 39, 259/D1G. 43 ABSTRACT lnt. A means and wherein a v v port1on of an an [58] held of Search D 6 2; supply is diverted, subject to intense turbulence, then I injected into a fuelsupply .to create a turbulent fuelair premixture which is immediately introduced, into [56] References Cited the air supply. Further included in some embodiments UNITED STATES PATENTS is a means of producing mechanical vibration in parts 3 located 1n the region wherem premixlng occurs, and in 1,729,382 9/1929 Harel "26I/DIG- 39 the region wherein introduction of the premixture into 3,332,231 7/1967 Walsh ..261/79 R the main air Supply Occm 7 2,453,595 ll/1948 Rosenthal ..261/1 1,752,506 4/1930 Portail ..261/79 R 7 Claims, 13 Drawing Figures PA'Ti'mimuszz m2 SHEET 1 OF 2 INVENTOR. [EA B40 )4. 500m MEANS OF PREPARING A FUEL-AIR MIXTURE BACKGROUND OF THE INVENTION It is well established that the efficiency with which a fuel-air mixture may react and, hence, the amount of contaminants in the residue is related to the degree and character of the intermixture of fuel and air prior to reaction. More specifically, in the operation of internal combustion engines, it has long been recognized that improved performance'and reduction of pollutants can be attained if the fuel and air or either component is subjected to sonic or ultrasonic vibrations or turbulence.

Attempts have been made to accomplish this by utilizing piezoelectric crystals exposed to either or both combustion components; however, the cost is high and the efficiency is low due to the problem of effective transfer of energy from the crystal to the component.

Also, attempts have been made to. utilize acoustical means to produce the desired vibrations or turbulence in one or both components. An example of this ap proach is shown in U.S. Pat. No. 2,532,554, in which a version of the I-Iartmann supersonic generator is used. This has required the use of air under pressure, and hence, the use of a compressor; even then, the effect seems to have been minimal, for although this approach to the problem has been available for many years, it has never come into use.

Also, for many years, an acoustical device known as a vortex whistle has been known. An example is a paper presented by Vonnegut in the Journal of Acoustical Society of America, Volume 26, No. l, in January of 1954. Again, although this approach has been known for many years, it has not come into general use, and in the few cases where the vortex whistle has been adopted, the resulting structure seems to have been too expensive and complicated for incorporation in the fuel supply systems of internal combustion engines.

SUMMARY OF THE INVENTION The present invention is directed to a means of preparing a fuel-air mixture which overcomes the problems heretofore encountered and is summarized in the following objects:

First, to provide a means of preparing a fuel-air mixture wherein a portion of an air stream is diverted, subjected to intense turbulence, then injected into a fuel supply to create a turbulent fuel-air premixture which is immediately introduced into the air supply.

Second, to provide a means, as indicated in the preceding object, in which an adaption of a vortex whistle is utilized to generate turbulent vibrations which are not merely effective to break up liquid fuel into smaller droplets, but apparently produces an unstable foam comprising air particles surrounded by a film of fuel which rapidly disintegrates when exposed to the main air supply to form an intimate extremely finely divided fuel mixture therewith.

Third, to provide a means, as indicated in the other objects, which is particularly adapted to supply combustion components to internal combustion engines and wherein the vortex whistle is operated by a pressure differential established within the main air passage or barrel of a carburetor.

Fourth, to provide a means, as indicated in the other objects, which may utilize a conventional carburetor modified to incorporate a novelly arranged vortex whistle, or a plurality of vortex whistles if the carburetor is provided with more than one barrel, with the result that improved engine performance may be accomplished at minimum expense.

Fifth, to provide a means, as indicated in the other objects, wherein the vortex whistle discharges across a fuel passage and impinges against a reflecting and focusing surface to intensify the turbulence in the region of initial mixture with the fuel.

Sixth, to provide a means, as indicated in the other objects, which utilizes the diverted air stream to produce mechanical vibration of parts exposed to the fuel in the region wherein premixture occurs and in the region wherein introduction of the premixture into the main air supply occurs.

Seventh, to provide a means, as indicated in the preceding object, wherein the mechanical vibration of the parts is produced by rotation of a solid mass in the vortex whistle chamber.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged fragmentary section view of a conventional carburetor which has'been modified to incorporate, the means for preparing the fuel-air mixture.

FIG. 2 is a fragmentary plan view, taken from 22 of FIG. 1.

FIG. 3 is an enlarged fragmentary sectional view, taken through 3-3 of FIG. 2.

FIG. 4 is a partial plan, partial sectional view, taken through 4-4 of FIG. 3.

FIG. 5 is a fragmentary sectional view, similar to FIG. 3, illustrating a modified construction.

F IG. 6 is an enlarged transverse sectional view, similar to FIG. 4, taken through 6-6 of FIG.-7, showing a modified construction.

FIG. 7 is a longitudinal sectional view, taken through 7-7 of FIG. 6.

FIG. 8 is a transverse sectional view, corresponding to FIG. 6, showing a further modification.

FIG. 9 is a further enlarged fragmentary sectional view, showing a modified wall of the vortex chamber.

FIG. 10 is a transverse sectional view of a further modification, taken through 10l0 of FIG. 1 1.

FIG. 11 is a longitudinal sectional view, taken through 11-11 of FIG. 10.

FIG. 12 is a fragmentary sectional view of a carburetor, corresponding to FIG. 1, showing a modified construction. g

FIG. 13 is a fragmentary plan view, corresponding to FIG. 2, but taken from 1313 of FIG. 12.

The present invention may be incorporated in an otherwise conventional carburetor, if the resulting fuel mixture is intended for an internal combustion engine. The carburetor, designated 1, is provided with one or more barrels or main air passages 2. In each passage is centered a venturi tube 3, supported in place by a radially extending fuel supply tube 4. The supply tube intersects an annular distributing passage 5, located within the venturi tube 3, and having ports 6 which intersect the venturi passage 7 in its region of smallest diameter, this being the zone'or region having the minimum pressure; that is, a pressure lower than the normal pressure of the air flowing in the passage 2.

1 boss 8, on which is mounted a vortex whistle unit 9. The vortex whistle unit includes a body 10, of circular configuration, having a stem 1 1 press fitted in or otherwise secured in the boss 8. The stem 11 forms an outlet passage 12 from the vortex whistle unit which intersects the passage formed within the fuel supply tube 4.

The body 10 forms a cylindrical vortex chamber 13 at the upper end of the passage 12, the vortex chamber being substantially larger than the outlet passage. The upper end of the vortex chamber is closed by a cap 14.

The upper portion of the vortex chamber ,is surrounded by a wall 15 of reduced thickness, and immediately below the cap 14 thewall 15 is provided with one or more tangential inlet ports 16. In the construction illustrated, two inlet ports are provided, but an additional number may be used if desired. The body 10 receives a deflector ring 17, which projects upwardly in spaced relation to the reduced wall 15, and its inner surface converges upwardly.

The method of preparing a fuel-air mixture utilizing the carburetor and the vortex whistle is as follows:

A conventional throttle valve, not shown, is located below the venturi tube 3. Variation in position of the 1 throttle valve determines the amount of air which flows downwardly through the passage 2. A portion of the air determined by the size of the deflector ring I 17 is diverted to the inlet ports 16 and on entering the ports is caused to form a vortex within the chamber 13.The vortex is intensified by its reduction in diameter as it flows outwardly through the passage 12. The air discharging from the outlet passage 12 impinges upon liquid fuel flowing through the supply tube 4, and the resulting premixture flows into the annular distributing passage for discharge through the ports 6 into the venturi passage 7. t

The force which produces this movement of the air diverted from the main .body of air flowing in the passage 2 is derived from two.complementarysources.

First, the air on impinging against the upper end of the body and the surrounding deflector ring 17 increases in pressure with respect to the normal pressure of the air flowing in the passage2. Second, the venturi passage produces a pressure which is' lower than the pressure of the main body of air. As a result, the-pressure differential is sufficient to create a turbulent vortex within the chamber 13. This vortex is intensified and rendered more turbulent as it enters the outlet passage 12. This is due to the fact that as the radius of rotation is reduced, .the speed of rotation increases. The air which discharges from the passage 12 is highly turbulent and undergoes intensive vibration with the result that it immediately reacts with the liquid fuel 18 in the supply tube 4. to produce an unstable and intimate intermixture of air and fuel. It is believed that the resulting mixture is in the form of an unstable froth or foam, comprising air particles surrounded by extremely thin membranes of fuel in a liquid state. in any case, the highly agitated mixture passes rapidly fromthe point of initial mixture to the points of discharge through the ports 6 into the venturi passage 7. Whether or not there is actually transient stage in which an actual froth exists, the particles of liquid which enter the venturi tube are materially smaller than the particles normally received in the venturi tube of a conventional carburetor.

Tests have established the fact that when the construction hereinbefore described is substituted for a fully conventional carburetor, a material reduction in carbon monoxide output is attained. Byway of example, an automobile having a carbon monoxide output in the order of 5 per cent under conventional conditions shows a carbon monoxide output too small to obtain a reading on a carbon monoxide meter.

One series of tests involved the use of a new carburetor installed in a late model automobile. Performance tests were first made of the carburetor without modification, as follows:

1. Under idling condition, the carbon monoxide output (CO) was nominal, approximately 0.2 percent.

2. Under steady state conditions, with the vehicle in motion and stationary, and with partially openthrottle representing speeds in the range between 25 and 35 miles-per-hour, the exhaust discharge *a'veraged approximately 2.5 percent CO. Y

3. Under steady state high speed conditions,

representing freeway travel in the range between 60 and miles-per-hour, the exhaust discharge averaged V approximately 1.0 percent CO. e

4. Under conditions of rapid throttle acceleration and deceleration, with the vehicle in motion or stationary, the CO content increased substantially, to the range between 5 and 7 percent.

Performance tests were then made with the same vehicle and carburetor modified by addition of the present invention; that is, a'device as shown in- FIGS. 1 through 4 was installed in each barrel of the two barrel carburetor and tested as follows;

1. Under idling conditions, as expected, no significant change in CO contentoccurred; that is, the CO content was 0.2 percent. I

'2. Under steady state conditions, in the 25 to 35 miles-per-hourrange, the CO content dropped approximately one-half to about 1.25 1.5 percent.

3. Under high speed steady state conditions in the 60 to 70 miles-per-hour range, a similar reduction -occurred, the CO content being in the order of 0.5 percent.

4. Under conditions of rapid throttle acceleration and deceleration, a greater effective reduction of CO ranged between 2 and occurred; that is, the CO content 3 percent.

It was also noted thatthe durations of the peak conditions resulting from acceleration and deceleration passage 12 is located perpendicular to the fuel supply I tube 4, or nearly so, and a concave reflecting surface 19 is located in the wall of thetube 4, diametrically opposite from the outlet passage 12. The reflecting surface has the effect of further intensifying the turbulence and increasing the intimacy of mixture between the air and fuel.

Reference is now directed to FIGS. 6-and 7. The vor-.. tex whistle or vibration generator 9 is essentially the same as in the first described structure, except that the inlet ports 16 are located midway between the top and bottom of the vortex chamber, and a pair of balls 20, having relatively high mass are free to rotate in the vortex chamber driven by the entering air. The balls are dimensioned so that each prevents the other from closing the outlet 12. While two balls are preferred, three or more could be used.

The balls, when rotated, produce a mechanical vibration which is transmitted by the walls of the vibration generator to the walls of the tube 4 and even to the walls of the venturi tube 3. This mechanical vibration supplements the sonic vibration occurring in the air and fuel. Cylinders 21 may be substituted for the balls 20 and are dimensioned to be positioned vertically or horizontally, the latter position being indicated in FIG. 8

Reference is made to FIG. 9 which illustrates a portion of the vortex chamber wall 15 having undulations 22 forming striking shoulders to increase the intensity of the mechanical vibrations.

Reference is now made to FIGS. and 11. The construction here illustrated includes a rotor 23 having an eccentric mass or blade 24 driven by the entering air and carried on a shaft 25 journaled in the cap 14. Rotation of the blade 24 causes intense mechanical vibration.

Reference is now made to FIGS. 12 and 13. While any of the constructions shown in FIGS. 6 through 11 may be substituted for the construction shown in FIGS. 1 through 5, mechanical vibration may be further increased by providing a boss 26 on the side of the venturi tube 3, opposite from the fuel supply tube 4, the boss having a hole therein to receive the stem 11. With this arrangement, the outlet 12 discharges directly into the main air stream, and the principal effect is to increase mechanical vibration of the venturi tube.

The effect of such mechanical vibration is to induce the vibrations into any liquid film on the surfaces of the venturi tube and its passages with attendant improvement in atomization.

While particular embodiments of this invention have been shown and described,'it is not intended to limit the same to the details of the constructions set forth, but instead, the invention embraces such changes, modifications and equivalents of the various parts and their relationships as come within the purview of the appended claims.

I claim:

1. The combination with a carburetor having an air passage; means in the air passage, operable during flow of air through the air passage, to produce a zone in the air passage lower than the normal pressure of air flowing in the air passage, and means defining a passageway for supplying fuel to said zone for entrainment in the air flowing in the air passage, of a sonic generator, comprising:

a. means defining a vortex chamber;

b. at least one inlet exposed to the air flowing in the air passage and directed tangentially into the vortex chamber to cause a turbulent air vortex in the cludes:

chamber;

c. and an outlet of reduced diameter directed axially from the vortex chamber into the fuel passageway adjacent said reduced pressure zone thereby to intensify the vortex turbulence of the air as it passes .through the outlet into the fuel passageway and to cause an intimate and turbulent premixing of air and fuel ior to dischar e int said educed pr ssure zon or entramme trn e arr owing m t e air passageway.

2. The combination of a carburetor and a sonic generator, as defined in claim 1, which further ina. means defining a channel exposed to the air receiving end of the inlet and directed upstream to convert a portion of the air velocity to increased pressure at the inlet thereby to increase flow of air into the vortex chamber.

3. The combination of a carburetor and a sonic generator, as defined in claim 1, wherein:

a. the discharge from the vortex whistle is transverse to the fuel passageway and a reflecting surface is located at the far side of the passageway to intensify the turbulent reaction between the air and the fuel.

4. A sonic generator, as defined in claim 1, wherein:

a. a rotatable mass is located in the vortex chamber to transmit mechanical vibration to the walls thereof.

5. A means of preparing a fuel-air mixture, comprisa. a tubular structure forming an air passage;

b. a venturi disposed in the air passage and creating a zone of reduced pressure;

c. a fuel passage connected to the venturi and subject to the reduced pressure zone to. deliver fuel thereto;

. a vortex whistle including a vortex chamber having an inlet exposed to air in the inlet passage and an outlet directed into the fuel passage adjacent its connection with the venturi;

e. said vortex whistle being responsive to the pressure differential between its inlet and outlet to' divert a portion of the air from the air passage to the fuel passage and generate turbulent vibrations in the diverted air, thereby to produce, with the fuel flowing in the fuel passage, a turbulent fuel-air

Claims (7)

1. The combination with a carburetor having an air passage; means in the air passage, operable during flow of air through the air passage, to produce a zone in the air passage lower than the normal pressure of air flowing in the air passage, and means defining a passageway for supplying fuel to said zone for entrainment in the air flowing in the air passage, of a sonic generator, comprising: a. means defining a vortex chamber; b. at least one inlet exposed to the air flowing in the air passage and directed tangentially into the vortex chamber to cause a turbulent air vortex in the chamber; c. and an outlet of reduced diameter directed axially from the vortex chamber into the fuel passageway adjacent said reduced pressure zone thereby to intensify the vortex turbulence of the air as it passes through the outlet into the fuel passageway and to cause an intimate and turbulent premixing of air and fuel prior to discharge into said reduced pressure zone for entrainment in the air flowing in the air passageway.

2. The combination of a carburetor and a sonic generator, as defined in claim 1, which further includes: a. means defining a channel exposed to the air receiving end of the inlet and directed upstream to convert a portion of the air velocity to increased pressure at the inlet thereby to increase flow of air into the vortex chamber.

3. The combination of a carburetor and a sonic generator, as defined in claim 1, wherein: a. the discharge from the vortex whistle is transverse to the fuel passageway and a reflecting surface is located at the far side of the passageway to intensify the turbulent reaction between the air and the fuel.

4. A sonic generator, as defined in claim 1, wherein: a. a rotatable mass is located in the vortex chamber to transmit mechanical vibration to the walls thereof.

5. A means of preparing a fuel-air mixture, comprising: a. a tubular structure forming an air passage; b. a venturi disposed in the air passage and creating a zone of reduced pressure; c. a fuel passage connected to the venturi and subject to the reduced pressure zone to deliver fuel thereto; d. a vortex whistle including a vortex chamber having an inlet exposed to air in the inlet passage and an outlet directed into the fuel passage adjacent its connection with the venturi; e. said vortex whistle being responsive to the pressure differential between its inlet and outlet to divert a portion of the air from the air passage to the fuel passage and generate turbulent vibrations in the diverted air, thereby to produce, with the fuel flowing in the fuel passage, a turbulent fuel-air premixture for delivery to the remaining air in the air passage through the zone of reduced pressure created by the venturi.

6. A means, as defined in claim 5, wherein: a. a rotatable mass is located in the vortex chamber to transmit mechanical vibration to the walls thereof.

7. A means, as defined in claim 6, wherein: a. a second sonic generator is mounted on the venturi to cause mechanical vibration of the walls thereof.

Images