CA1220104A - Carburetion system - Google Patents

Abstract

Abstract of the Invention.

A pressurized fuel carburetion system for internal combustion engines wherein varying velocities and pressures are produced in the throat of the carburetor intermixing fuel with the air passing therethrough in such a manner to create a plurality of vortices containing air and fuel mixtures rotating about an axis substantially perpendicular to the carburetor air flow. The carburetor includes a rota-ting baffle and fuel distributor producing a restriction in the carburetor throat to cause high air flow velocities and low pressures and the air subsequently expands in such a manner as to produce low air flow velocities and higher pressures creating the desired vortices. The fuel distribu-tor is in the form of a rotating cup, and fuel supplied to the cup interior is projected transverse to the air flow im-mediately prior to the region of vortex generation. Fuel supply control means utilize a plurality of series related valves employing engine manifold pressure and throttle posi-tion to control the rate of fuel supply and idling and ac-celeration fuel requirements are controlled by appropriate valves.

Description

~22031~

CARBURETION SYSTEM

1~ Background of the Invention.

2. The basic carburetion of internal combustion engines

3. consists of intermixing air and fuel to produce a mixture

4. of such .ratio as to support combustion. Many proposals have

5. been made for improving air and fuel mixtures to increase

6. the efficiency of fuel utilizaticn, improve engine perfor-

7. mance and running ~haracteristics, and aid in reducing the

8. cost of engine operation. Many approaches have been pro-

9. posed to improve the various aspects of carburetion, and

10. many patents exist disclosing carburetors and air-fuel

11. mixing devices for engines.

12. For instance, U.S. patents illustrating vortex genera-

13. tion within carburetors are shown in 2,054,734; 2,887,309;

14. 3,286,997 and German Patent 314,428. Also it has been recog-

15. nized that rotating vanes within the carburetor may aid in

16. fuel-air mixing, and examples of such carburetion devices

17. are shown in U.S. Patents 2,003,180; 2,595,719; 2,750,170;

18. 2,823,906; 3,439,903; 3,286,997 and 3,955,545. Additional

19. U.S. patents have recognized that the use of electric motors

20. to rotate carburetor components to improve intermixing and

21. and atomization of the fuel is of advantage as disclosed in

22. 2,932,495; 3,701,513 and 3,991,143.

23. While the aforementioned patents, in many cases, have

24. improved the efficiency to a minor extent of the associated

25. engines with which they are used, such carburetion systems

26. have not produced substantial increases in engine efficiency,

27. and even with the high fuel prices that are now commonplace

28. the development of high efficiency carburetors significantly ~220~

advancing the art has been elusive, and nonconventional approaches to engine carburetion are required if major advances are to be made in the art.
The invention provides a fuel/air mixing assembly comprising: a body having a throat: defined therein having a longitudinal axis extending between an air inlet and a fuel/air mixture outlet, the throat being circular in transverse cross-sectional configuration, an inverted cup having a closed up-stream end and a cylindrical wall extending from the upstream end to an open downstream end, the throat and the cylindrical wall being in spaced/parallel relationship to one another in the direction of flow from the air inlet to the mixture outlet, drive means rotatably supporting the cup for rotation within the throat, and fuel supply means Eor supplying fuel to the interior of the cup.
From another aspect, the invention provides a method of intermixing air and fuel for combustion purposes within a circular throat extending between an air inlet and a fuel/air mixture outlet comprising the steps of disposing an inverted cup with its exterior walls in spaced and parallel relationship to the interior walls of the circular throat and its closed end facing upstream flow from the air inlet and its open end facing downstream flow exiting the mixture outlet, rotating the cup while in the spaced relationship to the throat, and supplying fuel to the interior of the cup for dispersal therefrom and mix-ture with the air passing the open end of the cup.

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The configuration of the carburetor air flow gener-ates a plurality of vortices of mixing air and fuel particles having axes transversely disposed to the path of air flow, such vortices maintaining this orien-tation to produce improved flow, cleaning and burning characteristics within the engine intake manifold and cylinders.
The inverted cup provides a baEfle within the carburetor throat that produces sequential high velocity-low pressure and low velocity-high pressure regions, and creates a low pressure transition zone intermediate such regions capable of generating vortices of air and fuel particles having axes of rotation transversely disposed to the direction of carburetor air flow.
Pressurized fuel fed to the interior of the cup will be thrown from the downstream edge of the cup transversely into the path of air producing vortices of air and fuel having an axis transverse to the air flow direction.
Sequential high velocity-low pressure and low veloci-ty-high pressure regions are formed within the carburetor throat with a transition zone intermediate such regions, and a reduced pressure is created at the transition zone, such pressure differ-entials producing vortices of fuel and air particles rapidly intermixing about axes -transverse to the air flow within the carburetor throat, the fuel being introduced into the air flcw immedia-tely prior to the transition zone and a-t substantially right angles to the air flow path.

~.2~
In the practice of the invention fuel is supplied to a carburetor having a -throat in which an inverted cup-shaped baffle is concentrically located. The cup is rotated by an electric motor, and the fuel is introduced into the central region of the cup and produces a film within the cup interior such that the fuel is thrown from the downstream cup edge into the carburetor air flow at right angles thereto. The cup is of such configuration that an annular restricted cross sectional throat portion is defined in radial alignment with the cup pro-ducing a high veloci-ty-low pressure throat region, and below the cup the carburetor throat increasesin volume producing a higher pressure-low velocity region. Immediately below the cup a transition zone exists, and due to the cup configuration reduced air and vapor pressures exist below and interiorly of the cup where a plurality vortices of fuel and air particles are gener-ated which produces vigorous mixing of the air and Euel par-ticles. Such vortices are drawn into the engine, and tend to "scrub" the engine intake manifold preventing the accumulation of raw fuel thereon, and upon entering the engine cylinders pro-duce uniform combustion.
In the practice of the invention the objects thereofas set forth above are met, and significant improvements in engine efficiencies have been experienced.

Brief Description of the Drawings.
~ he aforementioned objects and advantages of the invention will be apparent from the following descrip-tion and accompanying drawings wherein:
Figure 1 is an elevational view, partially in diametrical section, of an internal combustion engine carburetor in accord with the invention, Figure 2 is a plan, elevational, sectional view as taken along Section II-II of Figure 1, Figure 3 is a plan, elevational, sectional view taken through the transitional zone of the carburetor throat along Section III-III of Figure 1, Figure 4 is a schematic, elevational, sectional view of a carburetion system in accord with the invention, Figure 5 is a graph illustrating typical engine operating characteristics during the practice o.E the invention, Figure 6 is a schematic, sectional, elevational view of an alternate control unit for regulating fuel control, l. Fig. 7 is an elevational view, partially in dia-2. metrical section, illustrating an embodiment 3. of carburetor in accord with the invention 4. wherein the cup baffle is axially adjustable 5. within the carburetor throat, 6. Fig. 8 is an enlarged, elevational, sectional view 7. of the cam means employed with the embodiment 8. of Fi~. 7 as taken along Section VIII-VIII of 9. Fig. 7, lO. Fig. 9 is an elevational view, partially sectioned, ll. illustrating the bimetallic fast idle and hot 12. idle linkages, and 13. Fig. lO is a schematic, elevational, sectional view 14. of an alternate fuel supply system utilizing 15. an electric fuel pump as used with the fuel 16. control unit illustrated in Fig. 4.
17. Description of the Preferred Embodiment.
18. The entire system of the invention is best appreciated 19. from Fig. 4 wherein the basic components of an internal com-20. bustion engine carburetion system are disclosed. The fuel 21. tank is represented at lO, and fuel is drawn therefrom by 22. the conventional diaphragm fuel pump 12 mechanically driven 23. from the engine, not shown, in the usual manner. A fuel ac-24. cumulator 14 receives the output from the fuel pump elimina-25. ting surges, and the fuel is filtered at 16 prior to being 26. received by the pressure regulator 18. The pressure regulator 27. supplies fuel to the control unit 20 and the pressurized 28. fuel output from unit 20 passes to the carburetor 22 mounted

29. upon the engine intake manifold schematically represented at

30. 24.

6.

~32 ~

1. More specifically, the pump 12 is connected to the 2. fuel tank 10 by an inlet conduit 26, and the pump pressurized 3. output is connected to the fuel accumulator by conduit 28.
4. The fuel accumulator uses a spring biased cylinder to absorb 5. fuel surges, and conduit 30 thexeof communicates with conven-6. tional fuel filter 16 which supplies the fuel pressure regu-7. lator 18 through conduit 32. The fuel pressure regulator 18 8. includes a valve 34 supported upon diaphragm 36 extending across 9. chamber 38 separating the chamber into portions 40 and 42.
10. Compression spring 44 biases the valve 34 toward a seated con-11. dition to the right, while spring 46 biases the diaphragm and 12. valve toward the left. The effective pressure face area on 13. the left of the diaphragm 36, and valve 34, is less than that 14. on the right of diaphragm wherein the diaphragm comprises a 15. differential pressure piston capable of positioning the valve 16. relative to its seat, and thereby control the rate of fluid 17. flow into the chamher 40. The fuel pressure regulator output 18. conduit 48 communicates with the chamber 40, and the metered 19. fuel from the control unit communicates with the chamber 42 20. through conduit 50.
21. The control unit 20 includes a body 52 in which sub-22. stantially similar valves 54 and 56 are mounted as separated 23. by a chamber 58. The valve 54 includes an annular groove 60 24. and radial ports communicating with an internal chamber and 25. orifice 62, while the valve 56 includes a circumferential 26. groove 64, and ports, communicating with the internal chamber 27. and orifice 66. A control needle or rod 68 is slidably re-28. ceived within the valve 54 axially positionable within the 29. orifice 62, while the control rod 70 is axially translatable 30. within the valve orifice 66. Each of the control rods is ~2,~

1. provided with a flattened surface 72 formed upon the as-2. sociated cylindrical rod such that the transverse cross 3. section of the control rod varies along its axial length.
4. Thus, the size of the opening w.ithin the orifices through 5. which fuel may flow will vary depending upon the axial po-6. sition of the associated control rod, and in this manner 7. fluid flow through the associated orifice can be very ac-8. curately controlled.
9. The control rod 68 is connected to an evacuated hel-10. lows 74 located within the chamber 76, and the chamber 76 11. communicates with the associated engine intake manifold 12. through conduit 78. The bellows 74 includes an internal 13. compression spring 80, the compression of.which may be 14. adjusted by the threaded spring pad 82.
15. The control rod 70 of valve 56 is connected to the 16. associated engine throttle mechanism which includes a 17. shaft 84 having a slotted arm 85 cooperating with the con-18. trol rod pin 88. Thus, as shaft 84 is rotated by the en-19. gine throttle linkage the rod 70 will be axially translated 20. within the val~e orifice 66.
21. From the above it will be appreciated that fuel en-22. tering the body 52 through conduit 48 may pass through 23. valve 54 and orifice 62 and into chamber 58, and from cham-24. ber 58 into the orifice 66 and through valve 56 into the 25. outlet conduit 90 communicating with the pressure regulator 26. conduit 50 and carburetor supply conduit 92.
27. During acceleration fluid flow to the carburetor is 28. primarily controlled by the acceleration valve 94 mounted 29. within body 52 and the valve 94 is supplied with fuel by 30. body passage 96, and the output from the valve flows to ~22~

1. valve 56 through body passage 98. The acceleration valve 2. includes a chamber 100 containing the piston-diaphragm ele-3. ment 102 connected to the valve 94, and compression spring 4. 104 adjustable through threaded shaft 106 will permit adjust-5. ment of the seating pressure of the acceleration valve. The 6. opposite side of the diaphragm 102, with respect to chamber 7. 100, communicates with a dashpot accumulator 108 communica-8. ting with the bleed orifice 110 and parallel check valve 9. 112, and both the bleed orifice and the chamber 100 communi-10. cate with the conduit 114 connected to the intake manifold 11. wherein, during acceleration when the intake manifold pres-12. sure decreases, the valve 94 will open permitting pressurized 13. fuel to flow therethrough into the carburetor supply line 92.
14. The fuel control unit 20 also includes a hot idle fuel 15. flow valve 116 receiving pressurized fuel through the body 16. passage 118 and a threaded needle valve type pin 120 controls 17. the fuel flow into the hot idle supply conduit 122 attached to 18. the carburetox 22 through the solenoid operated valve 124, as 19. later described.
20. The carburetor 22 in accord with the invention is il-21. lustrated in Fig. 1 and includes an adapter 126 attached to 22. the throttle blade valve plate 128 of intake manifold struc-23. ture 24 in which the conventional throttle valve 130 is lo-24. cated. The throttle valve 130 is connected to the engine 25. throttle linkage in th~ conventional manner, and rotative 26. positioning of the valve controls the amount of air and fuel 27. mixture entering the engine to regulate the rate of engine 28. rotation.
29. The carburetor body includes a -throat 132 mounted on 30. adapter 126 which is of a cylindrical configuration internally ~,2~4 1. defined by the cylindrical inner surface 134 which includes 2. a shoulder 13Ç forming a reduced diameter. The super struc-3. ture of the startex includes an upper support body 138 in 4. which ~he pressurized fuel supply line 140 communicates 5. with conduit 92 through solenoid operai.ed valve 142 and 6. air passages 144 are formed therein for receiving the car-7. buretor air throughout the circumference of the upper body 8. as indicated by the arrows.
9. The upper body 138 supports an electric motor 146 10. usually of the 12 volt variety having a driveshaft 148 sup-11. ported within bearing structure and the driveshaft is sealed 12. at 150 to the plate hub 152. As will be apparent from Fig.
13. 1, an annular chamber 154 is defined about the driveshaft 14. 148 which communicates with the fuel supply passage 140.
15. The driveshaft 14~ supports the shaft extension 156 16. coaxially aligned with the driveshaft which includes radial 17. ports 158 communicating with an axial passage, and lower 18. radial passages 160 which communicate with the fuel distri~
19. bution spokes or fingers 162.
20. A baffle in the form of a cup 164 is attached to the 21. extension 156 for rotation therewith, and the cup includes 22. the hub firmly mounted upon the extension, and the tubular 23. spokes 162 extend therethrough. The cup 164 includes an 24. upper closed end 166 disposed "upstream" with respect to 25. the direction of air flow as represented by the air flow ar-26. rows, and at the downstream end the cup is open as defined 27. by the circular edge 168. The spokes 162 are each provided 28. with a hole 17~ wherein the fuel within the spokes is dis-29. charged adjacent the inner surface of the cup cylindrical 30. wall 172, and centrifugal force due to cup rotation will 10 .

~2~

1. produce a film of fuel upon the cup inner surface and the 2. fuel will be rapidly thrown outwardly from the cup edge 168 3. in a direction and plane perpendicular to the air flow 4. through the carburetor throat 132.
5. As will be appreciated from Fig. 1, the configuration 6. and dimension of the cup 164 is such that a relatively large 7. chamber 174 will be defined upstream of the cup, but as the 8. cup wall 172 is disposed relatively close to the throat in-9. ner surface 134 an annular chamber is defined at 176 of re-10. stricted cross sectional area and tne velocity of air flowing 11. through the chamber 176 will substantially increase with 12. respect to the air flow velocity within chamber 174, and 13. the pressure within the chamber 176 will be lower than 14. at 174.
15. The greatest resistance to air flow will be at the 16. clearance 178 intermediate the throat shoulder 136 and the 17. lower region of the cup, and downstream from this annular 18. location the carburetox throat area again enlarges at cham-19. ber 180 producing a region of lower velocity and higher pres-20. sure when the ~alve 130 is open such that air flow is existing 21. in the carburetor throat. A transitional zone exists at 182 22. downstream of the cup and in the region adjacent the cup 23. edge 168. This transitional zone has a reduced air pressure 24. due to the venturi effect resulting from the configuration 25. of the cup and the high velocity of the air passing between 26. the shoulder 136 and the cup edge 168. Thus the "hollow"
27. nature of the cup and its axial dimension as defined by 28. the cylindrical cup wall 172 and parallel relationship to 29. the throttle throat inner surface 136 produces a venturi ef-30. fect resulting in a controlled turbulence within the transi-~L22~

1. tion zone 1~2 and the cham~er 180.
2. The aforementioned controlled turbulence results in 3. a plurality of vortices within the transition zone 182 and 4. chamber 180 and such vortices rotate about axes substantially 5. perpendicularly disposed to the axis of the throat and the 6. flow of air therethrough. As the fuel has been mixed with 7. the air as the air passes the cup edge 168 the vortices as 8. represented at 184 in Fig. 1, will contain fuel particles as 9. well as air particles and a thorough and rapid intermixing 10. of the particles and vaporization of the fuel occurs.
11. As the vortices 183 continue to rotate about their 12. axes the vortices are drawn into the engine intake mani~old 13. 124 and into the combustion cylinders. The direction of vor-14. tex rotation will continue to be substantially horizontal 15. as represented in Fig. 1, and such air and fuel movement 16. tends to "scrub" the walls of the intake manifold reducing 17. the likelihood of fuel adhering to the manifold walls which 18. produces a wet condition, as often occurs within engine in-19. take manifolds. Also, the vortexing of the fuel and air mix-20. ture continues into the combustion chamber distributing the 21. fuel throughout the combustion chamber facilitating burning 22. resulting in high efficiency utilization of the fuel.
23. The combination of the sequential flow of air from 24. the high velocity-low pressure chamber 172 to the higher pres-25. sure-low velocity chamber 180 and the ~ormation of the low 26. pressure transitional zone 182 immediately after mixing of 27. the fuel and air achieves a controlled vortexing of the fuel 28. and air mixture described above which significantly increases 29. the efficiency of combustion of the fuel more effectively uti-30. lizing the energy thereof.

1. As illustrated in Fig. 4, the hot idle circuit in-2. cludes the chamber 186 receiving fuel from the valve 124 3. and the chamber communicates with the carburetor throat at 4. orifice 188 adjacent the periphery of the valve 130 at valve 5. notch 190, and at the needle valve orifice 192, below the 6. throttle valve, the rate of fluid flow through the orifice 7. 192 being controlled by needle valve 1940 8. Operation of the solenoid valve 124 is by a limit 9. switch, not shown, connected to the throttle wherein, the 10. valve will be opened upon the throttle being released to 11. return to its usual "idle" position, and at such time the 12. valve 142 will close interrupting the main supply of fuel 13. through the conduit 92 and to the cup 164.
14. In the embodiment shown in Fig. 6, a modification of 15. hot idle fuel supply is illustrated. In this modification 16. similarly described components are indicated by primed re-17. ference numerals.
18. The body 52' includes the hot idle needle valve 116' 19. which communicates with supply passage 196, and the output 20. thereof communicates with the acceleration valve 94' through 21. passage 198. Thus, during idling, when no acceleration is 22. taking place and the intake manifold pressure is high, the 23. valve 94' permits fuel to flow through the valve 94' and 24. passage 98' through the fluid supply conduit 90', and this 25. construction eliminates a separate electric solenoid valve 26. in the hot idle circuit. In this embodiment notched openings 27. must be located in the throttle valve 130 to allow the fuel 28. and air mixture to enter the intake manifold.
29. With further reference to Fig. 6, a cold idle control 30. is shown which includes a bimetallic spring member 200 mounted ~zzo~

1. within block 20~ which is at$ached to the associated engine 2. block. Thus, the bimetallic spring 200 is subjected to 3. the temperature of the engine, and as the arm 204 is 4. affixed to the spring temperature variations in the bime-5. tallic spring will cause the arm to rotate. A cam slot 6. 206 defined in the bracket receives the follower pin 208 7. attached to the needle valve 210 and as the bimetallic 8. spring and arm rotate the position of the needle valve will 9. vary.
10. The block chamber 212 communicates with a filtered 11. air supply at 214, and the chamber also communicates with 12. the valve 210. Thus, air within the chamber 212 may be 13. drawn through the needle valve 210 into conduit 216 which 14. communicates with the control unit 20' at chamber 58' and 15. communicates with the engine intake manifold at 218. This 16. arrangement permits the vacuum within the chamber 58' to be 17. regulated in accordance with the temperature of the engine 18. allowing fuel enrichment during engine warmup. Once the 19. engine is warm the cold idle mode enrichment circuit will 20. be closed due to the closing of the needle valve 210, and 21. in this manner the valve 54' will provide the additional 22. fuel required during the initial engine warmup phase.
23. The acceleration valve 94t Fig. 4, and Fig. 6, 24. utilizes the bleed orifice 110 in series with the dashpot 25. accumulator 108. The bleed orifice and dashpot accumulator 26. limit the time that the acceleration mode circuit is actua-27. ted. The time that the acceleration circuit will be in use 28. is variable depending upon the amount of the differential 290 decrease in the manifold vacuum as sensed through conduit 30. 114 and the "on" time of the acceleration valve is directly /~

~ A

1. ~ependent ~pon the value of the differential decrease in 2. the manifold ~acuum. The check ~alve 112 within the bleed 3. orifice housing resets the timing circuit when the vaccum 4. increases.
5. With reference to Fig. 9, the lever 220 attached to 6~ the hot idle valve 116 is shown. The lever 220 cooperates 7. with a ~top set screw 222 mounted upon bracket 224 wherein 8. the amount of fllel passing through valve 116 may be readily 9. controlled. Also, the shaft of the bimetal spring 200 may 10. include an arm 226, Fig. ~, which supports a wire link co-11. operating with the pivotally mounted fast idle cam 228.
12. The fast idle cam is provided with a plurality of stop sur-13. faces 230 cooperating with the adjus ment screw 232 formed 14. on the hot idle le~er 220, and it w~ 11 be appreciated that 15. the position of the cam 228 will vary in accordance wi.th the 16. engine temperature presenting different adjustment screw 17. stop surfaces 230 in alignment with the screw 232 to control 18. the position of the idle screw lever ~20 and idle valve 116.
19. As the engine warms a lesser amount of fuel is required for 20. idling purposes.
21. In the graph of Fig. 5 typical operating relation.ships 22. of an engine in accord wi~h the invention are shown. The 23~ throttle range indicates the angular position of the throttle 24. blade 130l while the fuel flow indicates the percentage of 25. flow with respect to the maximum possible~ The curves indi-26. cate the relationship between throttle angle and fuel ~low 27. under various manifold vacuum conditions, and the road load 28~ is represented by curve A. As the manit-old vacuum decreases 29. the fuel flow increases as does the thrott~e angle.
30. A modification of carburetor relationships is illus-15.

1. trated in Figs. 7 ar3d B wherein components identical to 2. those previous:ly described are indicated by primed refer-3. ence n~nerals.
4. In this embodiment the motor 146' is supported upon S. the plate 138' ~y a ball and ramp assembly consistir.g of 6. plates 234 an~ 236 having a plurality of ball elements 7. 238 interposed therQbetween within obliquely disposed 8. grooves 240 and 242, as apparent in Fig. 8. The plate 236 9 is connected to motor 244 for rotating the plate ~bout the 10. motor axis, and such plate rotation will cause the balls 11. 238~ sevexal of which are used, to raise and lower the 12. motor, driveshaft and cup 164' in accordance with engine 13. performance. For instance, an expansi~le chamber motor 14. 244, such as a bellows in communication with the engine in-15. take manifold, is mechanically connected to the plate 236 16. wherein the axial position of the cup 164' within the 17. throat 132' will vary in accordance with manifold pressure.
18. It is possible to substitute a pnPumatic, mechanical or 19. electronic motor means for the ~acu~m means shown, if de-20. sired.
21. The axial position of the cup 164' may be varied 22. with respect to the throat and the throat shoulder 136' 23. which Yaries the spacing at clearance 178 controlling the 24. velocity of the air stream flowing therethrough. By con-25. trolling the dimension of the clearance 178 throughout the 26. range of engine speed optimum air flow characteristics can 27. be maintained thereby regulating the carburetor for optimum 28. efficiency and operation. The smaller gap will occur at 29. clearance 178 during high manifold vacuum conditions with 30. a closed throttle or idle speed, while the clearance will 1~ .

~;~2~

1. be increased at low vaccum open throttle conditions during 2. higher engine speed.
3. When the engine ignition is deactivated the solenoid 4. valves 142 and 124 close preventing fluid loss ~o the car-5. buretor, or flooding, and the use of the solenoid operated 6. valve provides complete control of the fuel supply to the 7. carburetor.
8. As shown in Fig. 4, the drive motor 146 may include 9. the upstanding threaded stud 24~ for receiving conventional 10. air filter structure, not shown, and it is to be appreciated 11~ that the carburetion system of the invention utilizes the con-12. ventional filters and anti-pollution equipment commonly em-13. ployed with motor vehicles and required by law.
14. In Fig. 10 the arrangement is shown which is used 15. with an electric fuel pump, rather than a diaphragm pump.
16. Electric pump 248 supplies regulator 249 having valve 250 17. controlled by diaphragm 252. When the pressure within cham-18. ber 254 becomes excessive the valve 250 opens and returns 19. fuel to tank 10' by return conduit 256. In this manner a 20. constant pressure is maintained on the fuel without becoming 21. excessive.
22. It is also to be appreciated that while a combination 23. pneumatic and mechanical control unit 20 is illustrated, 24. known electronic fuel control devices may be used with the 25. illustrated carburetor, and it is to be appreciated that 26. the carburetor disclosed is not dependent upon the fuel 27. supply and control apparatus shown.
28. The presence of the vortices 184 at the transition 29. zone 182 imparts to the air and fuel mixture a movement 30. highly advantageous with respect to in~er~ixing the small ~z~

1. air and fuel particles and produces a "scrubbing~ action 2. of the manifold walls as well as producing a turbulence 3. within the combustion chamber. Of course, a ve~7 fine 4. fuel-air mist and vapor exists within the transition 5. zone and therebelow, and the improved movement and inter-6. mixing of the air and fuel produces superior combustion 7. characteristics.
8. It is appreciated that various modifications to the 9~ inventive concepts may be apparent to those skilled in the 10. art without departing from the spirit and scope of the in-11. vention.

18.

Claims (6)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A fuel/air mixing assembly comprising; a body having a throat defined therein having a longitudinal axis extending between an air inlet and a fuel/air mixture outlet, said throat being circular in transverse cross-sectional.
configuration, an inverted cup having a closed upstream end and a cylindrical wall extending from said upstream end to an open downstream end, said throat and said cylindrical wall being in spaced/parallel relationship to one another in the direction of flow from said air inlet to said mixture outlet, drive means rotatably supporting said cup for rotation within said throat, and fuel supply means for supplying fuel to the interior of said cup.

2. An assembly as set forth in claim 1 including an annular shoulder within said throat adjacent said open end of said cup for creating a restriction to flow through said throat adjacent said open end of said cup.

3. An assembly as set forth in either claim 1 or 2 including adjustable cup-supporting means supporting said cup for axial movement longitudinally in said throat.

4. A method of intermixing air and fuel for combustion purposes within a circular throat extending between an air inlet and a fuel/air mixture outlet comprising the steps of; disposing an inverted cup with its exterior walls in spaced and parallel relationship to the interior walls of the circular throat and its closed end facing upstream flow from the air inlet and its open end facing downstream flow exiting the mixture outlet, rotating the cup while in the spaced relationship to the throat, and supplying fuel to the interior of the cup for dispersal therefrom and mixture with the air passing the open end of the cup.

5. A method as set forth in claim 4 including the step of restricting the flow adjacent the open end of the cup.

6. A method as set forth in either claim 4 or 5 including the step of moving the cup axially in the direction of flow.