US3256870A

US3256870A - Carburetor

Info

Publication number: US3256870A
Application number: US419418A
Authority: US
Inventors: Walker Brooks
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-12-18
Filing date: 1964-12-18
Publication date: 1966-06-21
Anticipated expiration: 1983-06-21

Description

June 21, 1966 B. WALKER 3,256,870

CARBURETOR Filed Dec. 18. 1964 4 Sheets-Sheet 1 f g f, w 32 June 21, 1966 B. WALKER 3,256,870

CARBURETOR Filed Dec. 18, 1964 4 Sheets-Sheet 2 /2 K 60V. {WITCH 71020 545 sw/rch' i v w l TH B. WALKER June 21, 1966 CARBURETOR 4 Sheets-Sheet 5 Filed Dec. 18 1964 June 21, 1966 B. WALKER 3,256,870

GARBURETOR Filed Dec. 18 1964 4 Sheets-Sheet 4 CV I. M

United States Patent 3,256,870 CARBURETOR Brooks Walker, 1280 Columbus Ave., San Francisco, Calif. Filed Dec. 18, 1964, Ser. No. 419,418 26 Claims. Cl. 12397) This application is a continuation-in-part of my copending application Serial No. 166,592, filed January 16, 1962.

This invention pertains to an improvement in a carburetor control for a vehicle that operates an appreciable time on decelerations when it is desirable to eliminate any flow of fuel to the main or idle jets during such closed throttle decelerations.

This invention involves the sucking out rapidly of al the fuel in the float chamber and the risers to the main and idle jets while at the same time shutting off the fuel flow to the float bowl from the fuel tank in order that no fuel will flow through the main or idle jets during the deceleration above a predetermined engine or car speed.

Other inventors have put suction on the carburetor bowl such as shown in FIG. 30 of the SAE Report No. 170, Automotive Exhaust Hydrocarbon Reduction During Deceleration by Induction System Devices," dated August 12-16, 1957. This involves boiling of the fuel in the bowl, slop over into the jets, etc., as related in the report, page 14, paragraph 13 of the above identified report.

Another object of the invention is to lift the float when the fuel is sucked out of the carburetor bowl so that no fuel can flow from the fuel tank by gravity (from a gravity-type tank) or by pressure from the fuel pump to the float bowl during this shut off period.

Another object is to make use of the float bowl needle valve to close off the flow from the fuel pump and fuel tank and thereby eliminate the necessity of introducing another valve and more fuel between the second valve and the float bowl which should be sucked out from the float bowl back to the shut off valve. This should simplify construction and reduce costs.

Another object of the invention is to provide a cylinder and piston to suck the fuel out of the carburetor bowl and allow the fuel that leaks by the fuel piston to flow back to the bowl while providing a continuation of the cylinder for fluid pressure, such as engine vacuum or suction from the engine intake manifold to operate a second piston in line with the first cylinder to power the fuel evacuating cylinder.

Another object is to provide a baflle for the fast return of the fuel to the float chamber so that fuel will not hit the float chamber breather hole which may bevented outside or to the intake to the carburetor.

Another object of the invention is to provide a diaphragm-type suck-out pump for the float bowl where engine intake manifold suction may be used to power the diaphragm to suck out the fuel as high suction is generally available when the fuel is to be sucked from the float bowl.

Rapid return of the fuel to the bowl to prevent engine stalling or reestablish power is desirable and available with this device with passage from the suck out pump to the float chamber being much larger than the fuel supply Patented June 21, 1966 mixture resulting from a very low fuel level in the float chamber existing during a portion of the suck out or fuel replacement cycle.

Another object of the invention is to locate the suck out pump below the carburetor float bowl so that once the fuel is sucked out of the float bowl and into the pump chamber there is no tendency for it to flow back to the bowl by gravity. On a very long deceleration, such as going down a mountain road, it may be desirable to 'have a dry float bowl for a long period of time and a pump located above the bowl could conceivably allow fuel to flow by gravity back into the bowl over a protracted period of time.

Other objects of the invention will be more particularly pointed out in the accompanying specification and claims.

I have illustrated my invention by way of example in the accompanying drawings, in which:

FIG. 1 is side elevation partly cut away of a carburetor employing one form of the invention;

FIG. 2 is side elevation partly cut away of a portion of the control circuit which could be used in FIG. 1;

FIG. 3 is a side elevation partly cut away showing a portion of a carburetor involving another form of the invention;

FIG. 4 is a side elevation of the same invention shown in FIG. 3 with the fuel sucked out of the float bowl;

FIG. 5 is a modification of the invention disclosed in FIG. 1; and

FIG. 6 is a further modification of the invention.

In all figures like numeralsrefer to similar parts in the various views.

In FIG. 1, I have shown a carburetor body 10 having an air horn 11, a choke butterfly 5, a choke control rod 6, a butterfly control shaft 8 for a throttle butterfly 7. Float 15 is pivoted on pin 16. Bell crank 15a is secured to float 15 and abuts against needle valve 17 which may be hexagon to pass fuel from seat 18 to the float bowl. Fuel line 19 is secured to the carburetor by nut 20. Fuel is fed to the idle needle 3 by passage 4, 4c, 4a and 4b to the lower portion of the bowl below float 15. Main jet fuel flows through orifice 12a, passage 12b, and ports in main jet venturi 12. The flow is controlled by screw 13 having a needle valve at its inner end 13a adapted to control the main jet fuel. At the bottom of the float bowl is a fitting 47 connected to the float bowl by a large opening. Fitting 47 is secured to pipe 46 by nut 47a. Tube 46 is large enough to carry the capacity of the float bowl in less than two seconds under normal operations. Tube 46 is connected to fitting 44 by nut 45. Fitting 44 is secured to diaphragm body 40a by hollow bolt 43 which will also pass the float bowl capacity in under two sec-.

onds. Diaphragm housing 40 and 40a are crimped toget-her over the outer diameter or diaphragm 49. Diaphragm 49 is secured to center portion 51 in a suitable manner, including washers 52 and 52a spread out over a portion of the diameter of diaphragm 49. A guide for center portion 51 is provided by the tubular extension 51a. Guide bolt 41 is threaded and engages the threaded portion of but; 40b of diaphragm body 40. The adjustment of bolt 41 will vary the possible stroke of diaphragm 49 and center 51 and can be changed--then locked and sealed by nut 42. Control of the suction to operate diaphragm 49 to suck out the fuel 9 from float bowl of carburetor 10 is by line 39 which connects to the engine intake manifold or to an engine partial vacuum pump or other suitable sources of vacuum. A check valve or flapper valve 38 in fitting 37, allows abuild up of engine vacuum in accumulator 36 between engine throttle changes and accumulates the higher vacuum of various driving cycles operated by the vehicle driver. Pipe or tube 35 is connected to the accumulator 36. The flow through tube 35a and tube 35 is controlled by flow control screw 121 and two bleeds. Tube 109 has an opening that is covered by soft pad 57 attached to control arm 56 for throttle shaft 8 so that the bleed opening of the tube 109 is closed when throttle butterfly is closed. Bleed tube 108 is closed by pad 107 when the governor 102 is driven above a speed such as 1000 r.p.m. of the motor or such other speed that return of the fuel to the carburetor bowl by the power from spring 55'will be soon enough so that the engine will not stall and provide good driva-bility.

As the throttle butterfly is opened transfer port 2 delivers fuel and air from the idle fuel bleed 122 and the idle fuel passage 4b, 4a, 4c, and 4 to idle adjustment screw 3 and idle orifice 1.

An alternate control of engine suction is shown in FIG. 2 wherein the engine suction is connected to line 39. To operate the structure of FIG. 1, or FIGS. 3 and 4, to be described, a check valve 38 sustains a higher than average engine suction in accumulator 36. A spool valve 112 with reduced diameter portion 113 is in line with the opening in tube 35 for control of the vacuum in the accumulator 36 by tube sections 35b and 350 to the pipe 34 of said figures to operate suck out diaphragm 49 against the force of return spring 55 to suck the fuel 9 out of the bowl of float 15. When the solenoid 110 is deenergized the spool valve 112 is raised by solenoid spring 120 so that the reduced portion 113 is above the opening in tube 35, then air bleeds to the opening 35 from port 114 by this raising the end of spool valve 112 as shown in dotted lines, FIG. 2. In this raised position of spool valve 112 the suction is cut off from below diaphragm 49 and air is admitted through port 114 below the end of valve 112, through

pipe

35a, 35, 34 to the under side of diaphragm 49 to allow the force of spring 55 to push diaphragm 49 to the position shown in FIG. 1 where the fuel 9 is returned to the bowl of float 15.

Solenoid 110 when energized holds the valve 112 in the full line position shown in FIG. 2. which supplies suction to line 35 which in turn lowers diaphragm 49 in FIG. 1 or raises cups 89 and 90 of FIG. 3 tothe position shown in FIG. 4 to suck the fuel 9 from the carburetor bowl and shut off fuel flow to thecarburetor. When solenoid 110 is deenergized by the opening of the governor and the throttle switches, armature 121 on the valve stem 112 moves up by spring 120 toallow bleed air to enter through port 114 to return fuel to the float bowl with diaphragm 49 in the position shown in FIG. 1. Stop plate 123 is preferably non-magnetic such as fibre, plastic, brass, etc. and spring 120 bears against it to raise valve stem 112 so that the line from 35b to 350 is closed and 35 is open to the atmosphere, so that spring 55 and diaphragm 49 return the fuel to the carburetor bowl in FIG. 1. In FIGS. 3 and 4, spring 125 forces cup 90 down to return the fuel to the carburetor bowl, as in FIG. 3. The solenoid 110 is connected to the vehicle battery in series with the ignition switch so that no drain can exist on the battery from this solenoid circuit when the ignition is off. The circuit includes two switches in seriesone connected to a speed sensitive device or gov-.

ernor that closes the switch above a predetermined speed of around 30 miles per hour. The throttle switch is closed when the foot throttle (not shown) is in the throttle closed or engine idle position. This results in closing the circuit to the solenoid when the foot throttle is in the closed or idle position and the car is traveling above 30 miles per hour, as in a high speed deceleration or deceleration above 30 mph. This is the condition'shown in FIG. 2 and FIG. 4. Fuel is returned to the carburetor when the speed gets below 30 mph. with the foot throttle closed so that the engine will not stall because the governor opens the governor switch below 30 mph. and the throttle switch is closed and the solenoid is not energized so that valve stem 112 is raised and atmospheric pressure returned to line 35 and fuel is returned to the carburetor bowl. In the operation of the solenoid 110 as described valve 112 is raised when the solenoid is not energized when either the governor switch or throttle switch is open. If, when decelerating above 30 mph. with both switches closed the solenoid energized valve stem 112 is moved down, as shown in FIG. 2, fuel is drawn out of the bowl. If during such .a deceleration the trrottle is opened, the throttle switch will open, deenergizing the solenoid, valve 112 will raise admitting the atmosphere to line 35 returning fuel to the bowl for part open throttle or full open throttle power.

Returning to FIG. 1, I have shown a small diaphragm 27 connected to rod 25 and to rod 21 which has a turned or T end 21a which holds up float 15 when the fuel is drawn from the float bowl by a partial vacuum in lines 35-34-31 and below diaphragm 49. This same engine vacuum operates above diaphragm 27 enclosed in diaphragm body 29. Spring 28 urges diaphragm 27 downward to free float 15 to allow fuel to enter through needle valve 17 to maintain the fuel at the desired level in bowl of float 15 after the fuel has been returned to the float bowl and the suction below the diaphragm 49 and above diaphragm 27 returned to, atmospheric pressure. This is accomplished by the device shown in FIG. 2 by the raising of valve 112 to allow tube 35a to connect to air port 114 if the control shown in FIG. 2 is used. If the control shown in FIG. 1 is used whenever the

bleed tube

109 or 108 is opened by throttle control 56 or governor 102

diaphragms

49 and 27 will assume the position shown in FIG. 1. Throttle operated valve 57' and governor operated valve 107 are shown closed as just before suction has moved diaphragm 49 or diaphragm 27 against

springs

55 and 28 respectively as when starting to decelerate above 30 mph. with a closed foot throttle. Deflector 124 prevents the sudden rush of fuel back to the bowl of float 15 from butting the float 15 and/or float bowl breather tube 125.

In FIGS. 3 and 4 I have shown a carburetor body 50, a bowl for float 152. Float 152 rises and falls on fuel 9 and is pivoted by pin 151 .and has an arm extension 152b. Extension 1521) presses on hexagonal needle valve 153 to close on seat 154 to stop fuel from entering through fuel pipe 19 which leads to a gravity fuel tank or fuel pump not shown. The main jet and idle jet intake is from well below the top of the fuel 9 in the bowl of float 152, such as is shown in FIG. 1. Other desired types of main and idle fuel feed systems from the float bowl can be employed.

Outlet 150f at the low point in the bottom of the bowl for float 152 is connected by fitting 159 to the bottom of cylinder 61. Cylinder 61 has a step against which diaphragm 63 is held securely by spacer sleeve 62 which forms the cylinder wall for upper piston cup 83 which is vacuum actuated. The lower end of the cylinder 62 is vented to the atmosphere by port 61a extending through cylinder 61. Cup 83 may be made of leather or other suitable material and is secured to piston rod by nut 81, upper washer 82, and lower washer 84. Expander spring 84a is nested in a recess of lower washer 84 and presses against the lip of cup 83. Enlarged internally threaded portion a of lower piston rod 85 secures washer 84 against cup 83, washer 82 and nut 81 to form a secure upper piston assembly. Diaphragm 63 may have a seal such as O-ring 63a to seal rods 85. Lower piston cups 89 and are secured to rods 85 by washers. 88 and 92 respectively. Expander ring or spring 87 expands the lip of cup 89 and spring 91 expands the lip of cup 90. Bolt 160 secures fitting 159 to the lower head of cylinder 61. Holes around the bolt 160 permit rapid flow of fuel from the bowl of float 152 to cylinder 61 below cup 90 when cup 89 is drawn upward by partial vacuum above cup 83 in spacer sleeve 62. Bolt 158 engages spider 156 to hold fitting 159 secured to the bottom of the bowl of float 152. Holes 157 in spider 156 direct the flow of fuel returned to the bowl of float 152 outwardly rather than vertically so as not to reach bowl vent 50e which may be to the atmosphere or to the carburetor horn, such as vent 125 of FIG. 1.

Rod 93 has lower collar 94 secured by a pin and upper collar 95 secured by a pin. Spring 96 urges rod 93 upward. Arm 65 is secured to piston rod 80 by a pin at hub-65a. End 65b abuts against rod 93 to depress spring 96 to allow float 152 to follow the level of fuel 9 down to where fuel will be admitted, as shown in FIG. 3, past needle valve 153 to fill the bowl of float 152 to the proper level.

When cup 83 raises cup 89 as on decelerations by suitable controls, as shown in FIGS. 1 and 2, the fuel is rapidly withdrawn from the bowl of float 152, as shown in FIG. 4. As soon as end 65b of arm 65 moves upward to start the evacuation of the fuel from the bowl of float 152, spring 96 raises rod 93 and flange 94 raises float 152, so that extension 152!) forces needle valve 153 to close on seat 154 to stop the flow of fuel from pipe 19 through passage 154 .so that no fuel can flow from pipe 19 to the bowl of float 152 while the end 65b of arm 65 is above and out of contact with rod 93 which exists during the evacuation and return of fuel 9 from the bowl of float 152.

Piston rods

80 and 85 are returned to the position shown in FIG. 3 from that shown in FIG. 4 by spring 125 which is attached to end 65c of arm 65 and at its lower end to the end of extension 61b, which arm is attached to the head and side of cylinder 61. Guide pin 64 prevents arm 65 from rotating by passing through a hole therein.

Cup 83 pulls piston rod 80, piston rod 85, and cup 89 upward when partial vacuum from the engine manifold is admitted through tube 35 and passage 71. Control of the vacuum through tube 35 could be by controls, such as are shown in FIGS. 1 and 2, or by such other suitable controls, one of which is shown in Mallory, US. Patent 2,395,748, dated February 26, 1946. Solenoid 110 of FIG. 2 may be controlled by suitable switches such as are shown in SAE Report No. 170, see FIG. 26. In order to take care of the breathing above cup 89 and below diaphragm 63, I have provided a

passage

100, 99 and 101 from the upper end of cylinder 61 below diaphragm 63 so that air (and a very small portion of fuel which might seep past cups 90 and 89) passes freely back into the top of the bowl of float 152.

The form of the invention shown in FIG. 5 is similar to that of FIG. 1 and the same numerals are used to designate the same parts. However, in FIG. 5 an adjustable, threaded type needle valve T is provided in conduit 31 to throttle the flow of air to the motor means M and a check valve CV is provided to by-pass the needle valve T to allow a fast withdrawal of air from the motor and to prevent return of air thereto.

' In operation, a vacuum is applied simultaneously to the motor M and the vacuum motor VM of the pump P to simultaneously withdraw the fuel 9 from bowl of float 15 and to force and retain valve 17 on its seat 18 to prevent flow of fuel into the bowl. When the vacuum is broken however by admitting atmospheric air, spring 55 and diaphragm 4 9 will operate toqu-ickly return the fuel to the bowl. Due to the adjustable throttle valve T the breaking of the vacuum in the motor M is delayed until the fuel has been returned to the desired level in the bowl. After this delay period the spring 28 urges diaphragm 27 downwardly and with it the yoke 21 is lowered to remove the support 21a from the under side of the float 15 and lever 15a and thus disconnect the motor M from the normal

valve operating mechanism

15, 15a, and thus return control of the valve 17 to the float 15.

g The form of the invention illustrated in FIG. 6 is similar to that of FIG. 5 and the same numerals are therefore used to designate the same parts. However, in this modified form of the invention the bottom of the bowl is formed by a bellows B which is an expansible chamber. In this manner the bellows construction with the pivoted lever and motor take the place of the VM and P of FIG. 5. The volume of the chamber in the expanded condition of the bellows illustrated in full lines in the drawing is equal at least to the volume of fuel to be drained or lowered from the bowl, the same as in the case of the pump P, in FIGS. 1 and 5. The bellows is therefore expanded by a vacuum motor VM in which a piston 49a having a rod 4% is suitably connected to the bottom of the bellows by a lever L and link L pivoted at an intermediate point on a bracket N fixed to the bowl and is collapsed by a return spring S fixed to the bowl and lever L. In operation a partial vacuum is applied simultaneously through pipe 34 to the motor VM at the upper side of the piston 49a. The piston of the motor VM operates to expand the bellows to withdraw the fuel from the bowl and to simultaneously raise the rod 25 to thereby rotate bellcrank 15a to press valve 17 onto its seat 18 to prevent flow of fuel into the bowl. When the vacuum is broken by admitting atmospheric air the bellows is collapsed by the spring S to return the fuel to the original level in the bowl, as shown in the dotted line position. Due to the adjustable throttle valve T the breaking of the vacuum in the motor VM is delayed until the fuel has been returned to the original level. After this delay period the support 21a is removed from supporting the bellcrank 15a as stated before, to disconnect the motor from the

valve operating mechanism

15, 15a to return control of the valve 17 to the float, also shown in dotted lines in FIG. 6.

I have illustrated my invention in these various forms; however, many other variations may be possible within the scope of this invention.

To those skilled in the art to which this invention relates many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. The disclosures and description herein are purely illustrative and are not intended to be in any sense limiting.

I claim:

1. A carburetor comprising a bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel therein, means for drawing the fuel from the bowl, means for closing the valve means for preventing flow of fuel into the bowl when the fuel is drained therefrom, means for returning the fuel to the bowl, and means for opening the valve means after the fuel has returned to the bowl.

2. A device as in claim 1, wherein the means for draining the fuel from the bowl comprises a pump, a source of vacuum, and means for connecting the pump to said source.

3. A device as in claim 1, wherein the means for closing the valve means comprises a motor, a source of vacuum, and means for connecting the motor to said source.

4. A carburetor comprising a bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel therein, pump means for withdrawing the fuel from the bowl, a motor connected to the valve means for closing the valve means to prevent flow of fuel into the bowl when the fuel is drained therefrom, a common source of vacuum for said pump and motor, means for simultaneously connecting the pump and motor to said source to simultaneously withdrawing the bowl and close the valve means, and means for returning the fuel to the bowl and disconnecting the valve means from the motor after the fuel has returned to the bowl.

5. A carburetor comprising a bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel .therein, pump means for draining the fuel from the bowl, a motor connected to the valve means for closing the valve means to prevent flow of fuel into the bowl when the fuel is drained therefrom a common source of vacuum for said pump and motor, means including conduits for simultaneously connecting the pump and motor to said source to simultaneously drain the bowl and close the valve means, means for breaking the vacuum to the pump and to pump the drained fuel back into the bowl, and means for breaking the vacuum to the motor a predetermined time after the vacuum to the pump is broken and to disconnect the motor from the valve.

6. A device as in claim wherein the means for breaking the vacuum to the motor a predetermined time after the vacuum to the pump is broken comprises an adjustable throttle valve in the conduit to the pump.

7. A device as in claim 6 wherein the means for simultaneously connecting the pump and motor to the vacuum source comprises a check valve in the conduit to the pump by-passing the throttle valve to allow air flow away from the motor and prevent air flow to the motor.

8. A carburetor comprising a bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel therein, means for draining the fuel from the bowl and returning the drained fuel thereto comprising a pump and a conduit connecting the pump and bowl, means for closing the valve means for preventing flow of fuel into the bowl when the fuel is drained therefrom, and means for opening the valve means after the fuel has returned to the bowl..

9. A carburetor comprising a bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel therein, an expansible chamber connected to the bottom of the bowl and having a volume in the expanded condition at least equal to the volume of fuel to be drained from the bowl, pump means for expanding and contracting the chamber to withdraw fuel from the bowl and return the withdrawn fuel to the bowl, means for closing the valve means for preventing flow of fuel into the bowl when the fuel is drained therefrom, and means for opening the valve means after the fuel has returned to the bowl.

10. A device as in claim 9 wherein the expansible chamber is a bellows secured to the bowl.

11. A carburetor comprising a source of vacuum and a fuel bowl, valve means for controlling the flow of fuel into the bowl to maintain a predetermined level of fuel therein, means for lowering and reestablishing said predetermined level of fuel in said bowl, separate means for controlling the flow of fuel to said bowl during the lowering of said predetermined level of fuel in said bowl, and said bowl having means responsive to the source of vacuum in said carburetor to simultaneously control the level of said predetermined level of fuel in said bowl and the supply of fuel to said bowl.

12. The structure of claim 11 wherein said means for lowering and reestablishing said predetermined level of fuel in said bowl comprises a vacuum pump.

13. The structure of claim 11 wherein said means for lowering and reestablishing said predetermined level of fuel in said bowl comprises a bellows.

14. A carburetor for a vehicle engine having a float bowl, a float, fuel on Which said float usually floats, a needle valve controlled by said float, fuel jets, said fuel jets connected to said float bowl below the top of the fuel in said bowl when said needle valve is closed by said float, a second chamber capable of storing the fuel from said float bowl, said second chamber being of variable volume, a fuel passage connecting said second chamber to said float bowl, said fuel passage being open to rapid fuel passage in either direction between said bowl and said second chamber, power means for expanding the volume of said second chamber to rapidly suck all the fuel from said float bowl, and power means for simultaneously closing said needle valve during the period said fuel has been sucked from said float bowl to said second chamber, other power means for returning said fuel rapidly from said second chamber to said float bowl.

15. A structure as described in claim 14, in which said second chamber is below said float bowl, and includes a movable diaphragm power controlled to remove the fuel from said float bowl during high speed decelerations whether the brakes are applied or not.

16. A structure as described in claim 14, in which said power means includes an engine intake manifold suction powered device, to move said fuel in one direction between said float bowl and said second chamber and spring means to move said fuel in the reverse direction between said float bowl and said second chamber.

17. A structure as described in claim 14, in which said second chamber has a diaphragm for part of its wall surface, said diaphragm being moved to vary the volume of said chamber and control the transfer of fuel from said float bowl to or from said second chamber, said diaphragm actuated in one direction by engine powered suction and in the other direction by spring means.

18. A carburetor having a throttle, a throttle control, a float, a float bowl, an engine for a vehicle connected to said carburetor, a second chamber connected by a conduit for fluid flow to said float bowl, power means for rapidly drawing fuel through said conduit from said float bowl to said second chamber and power means for rapidly returning said fuel through said conduit from said second chamber to said float bowl, a governor driven by said engine, said governor in series with other controls constrolling said power means.

19. A structure as described in claim 18, in which the power means to move the fuel from said second chamber to said float bowl includes a coil spring.

20. A carburetor having a throttle, a throttle control, a float, a float bowl, an engine for a vehicle connected to said carburetor, a second chamber connected for fluid flow to said float bowl, power means for rapidly drawing fuel from said float bowl to said second chamber and power means for rapidly returning said fuel ,from said second chamber to said engine, a governor driven by said engine, a carburetor throttle control, said power means including engine powered suction, a conduit connecting said suction from said engine to said power means, said conduit including a valve means controlled by said throttle control and governor.

21. A carburetor having a throttle, a throttle control, a float, a float bowl, an engine for a vehicle connected to said carburetor, a second chamber connected for fluid flow to said float bowl, power means for rapidly drawing fuel from said float bowl to said second chamber and power means for rapidly returning said fuel from said second chamber to said engine, said power means including two switches, one operated by said governor, the other operated by said throttle control so that said fuel is withdrawn from said float bowl at high speed deceleration.

22. A structure as defined in claim 21 in which said fuel is returned to said float bowl when said throttle is opened during a high speed deceleration.

23. A carburetor having a throttle, a throttle control, a float, a float bowl, an engine for vehicle connected to said carburetor, a second chamber connected for fluid flow to said float bowl, power means for rapidly drawing fuel from said float bowl to said second chamber and power means for rapidly returning said fuel from said second chamber to said float bowl, a governor driven by said engine, said governor in series with other controls controlling said power means, a throttle control for said carburetor, the power means being automatically actuated to withdraw the fuel from said bowl when said vehicle is operating at a high speed deceleration, said power means controlled by a function of engine speed and by the position of said throttle control.

24. A structure as described in claim 23, in which said second chamber consists of a cylinder and piston, the motion of said piston controlling the passage of fuel from said second chamber to said float bowl and vice versa.

25. A structure as described in claim 24, in which said carburetor has a needle valve controlled by said float, a fuel pressure supply to said carburetor, a mechanical connection between said piston and said needle valve to hold said needle valve closed when said piston is in the positions to withdraw fuel from said float bowl to prevent fuel from said fuel presure supply from entering said float bowl while said piston is in such a position to withdraw fuel from the float bowl.

26. A carburetor having a throttle, a throttle control, a float, a float bowl, an engine for a vehicle connected to said carburetor, a second chamber connected for fluid flow to said float bowl, power means for rapidly drawing fuel from said float bowl to said second chamber and power means for rapidly returning said fuel from said second chamber to said float bowl, a governor driven by said engine, said governor in series with other controls controlling said power means, said carburetor having main fuel jets and idle fuel jets, fuel paths leading from below the normal fuel level in said float bowl to said main and idle jets, when the fuel in said bowl is withdrawn to said second chamber the fuel level in said bowl being substantially below the intake to said fuel paths in said float bowl.

References Cited by the Examiner UNITED STATES PATENTS MARK NEWMAN, Primary Examiner.

I LAURENCE M. GOODRIDGE, Examiner.

Claims

1. A CARBURETOR COMPRISING A BOWL, VALVE MEANS FOR CONTROLLING THE FLOW OF FUEL INTO THE BOWL TO MAINTAIN A PREDETERMINED LEVEL OF FUEL THERIN, MEANS FOR DRAWING THE FUEL FROM THE BOWL, MEANS FOR CLOSING THE VALVE MEANS FOR PREVENTING FLOW OF FUEL INTO THE BOWL WHEN THE FUEL IS DRAINED THEREFROM, MEANS FOR RETURNING THE FUEL TO THE BOWL, AND MEANS FOR OPENING THE VALVE MEANS AFTER THE FUEL HAS RETURNED TO THE BOWL.