US3334649A

US3334649A - Carburetor float valve

Info

Publication number: US3334649A
Application number: US246653A
Authority: US
Inventors: Vernon F Thompson
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-12-17
Filing date: 1962-12-17
Publication date: 1967-08-08
Anticipated expiration: 1984-08-08

Description

Aug. 8, 1967 v. F. THoMPsoN CRBURETOR FLOAT VALVE 2 Sheets-Sheet l Filed Dec. 17, 1962 FIG.6

FIG] 5v FIGA4 FIG 5 Aug 8, 1957 v. F. THOMPSON 3,334,549

CARBURETOR FLOAT VALVE Filed Deo. l?, 1962 2 Sheets-Sheet 2 /5 a l /l 2 run ruw /ll/ //////////////f/ FIGJO IM fnl/117111111111 United States Patent O M 3,334,649 CARBURETOR FLOAT VALVE Vernon F. Thompson, 512 Larson Drive, St. Louis, Mo. 63126 Filed Dec. 17, 1962, Ser. No. 246,653 13 Claims. (Cl. 137-329.04)

'Ihis invention relates to carburetors for internal combustion engines and more particularly to oat operated valves for maintaining a more nearly constant fuel level in the fuel bowl of a carburetor. This application is a continuation-in-part of my prior application Ser. No. 54,655, filed Sept. 8, 1960, for Carburetor Float Valve, and claims this date for purposes of priority.

This invention can be differentiated as to operating `characteristics by first considering some of the recognized operating deficiencies of the conventional pointed steel needle valve which operates on. a conical seat usually formed in a Ibrass valve cage. The needle valve in such assemblies may be round but usually has a body which is polygonal in cross-section (usually triangular) dimensioned to have a siding t in the round barrel of a brass valve cage containing the valve seat and is guided in the barrel during its operation toward and away from the seat under the influence of the action of a iloat and its lever. Clearance between these parts is maintained close to prevent the needle from being cocked on its seat by the action of the iioat arm or lever which may impose forces eccentric of the needle. Since clearances are close between the needle and |barrel, the needle s not capable of a selfcentering action on its seat. This requires that the seat be exactly concentric with the barrel, and the needle valve pointed end exactly concentric with the guiding surfaces on the polygonal body of the needle, otherwise the needle and seat cannot be expected to hold gasoline. This is especially true as the needle turns on its seat, which it will do eventually. If the needle and seat are not gasoline tight, the engine will have poor hot starting and idling characteristics. It is well understood that under hood temperatures in the modern automobile may greatly exceed 200 F. when the engine is idling, and temperature increases after the engine is stopped, especially on a hot day. The initial boiling point of gasoline is just under 100 F., consequently, the fuel boils and the boiling fuel between the carburetor and fuel pump valves generates very high pressures. 'I'hese pressures cannot fbe Ibled off back through the pump valve, and, consequently, have a tendency to force the gasoline lby the needle valve to ood the fuel bowl when Valve seating is not perfect. The excess Vfuel ows out of the nozzles of the carburetor into the mani- (fold so that the restart after a hot soak is slow because the mixture supplied to the engine is enriched by gases in the intake manifold forming an unburnable mixture. 'I'hese poor restarts of an engine may be directly traced either to needle andseats which leak when subjected to pump pressure of three to seven pounds, or in which the needle area subjected to higher pressures during the hot soak is great enough to decrease the closing force imposed lhy the float and the oat arm. This decrease may cause leakage. To minimize this effect, carburetors are usually provided with floats of a size to develop as much mechanical pressure on the fuel inlet valve as float 4bowl size limitations permit in a given engine installation.

It is often the case in hot Weather that the fuel is not solid, but full of gas bubbles, so that the size of the inlet passage through the fuel inlet valve must have sulcient ilow capacity to more than meet the maximum rate of liquid fuel consumption of theengine. The liow capacity of the fuel inlet valve should not be less than this and, of course, this places a lower limit on the size of the inlet passage, on the other hand, the area of the valve exposed to fuel pressure should not be so large that the closing 3,334,649 Patented Aug. 8, 1967 ICC force of the valve on the seat produced by the lloat is reduced by the liquid pressure from the pump to the point where the valve has not a sufficient valve closing force on the seat to prevent leakage.

From the above discussion, it will [be apparent that given a minimum size for the inlet passage through a fuel inlet valve, a certain minimum is placed upon the mechanical force required to close that valve, which in turn has Ia lot to do with float size as well as carburetor oat bowl size. A great deal could be gained in reducing carburetor size, if this excess in valve closing force was unnecessary.

It is also characteristic of metal needle valves and seats that during operation at low engine loads the need for gasoline allows very little needle movement off the seat so as to allow but a small trickle of fuel through the Valve. This means that the clearance between valve and seat is infinitesimal. Any minute impurities, such as iron oxide in the gasoline, will then likely be trapped between the steel needle and its brass seat, so that the needle cannot seat and canburetor ooding results. It was because of these ditiiculties and still others, with which this description will not be burdened, that make the use of rubber valves, or rubber seats, or both, attractive. Especially now since elastomers have become available which act like rubber, Ibut unlike prior synthetic rubbers are resistant to gasolines, alcohols and additives used in gasoline up to 500 F. Such materials are known as liuorocarbon rubbers (copolymer of vinylidene fluoride and hexauoropropylene) sold under various trade names (Fluorel elastomer, Viton, Kel-F elastomer). The term rubber-like, used hereinafter, refers to rubbers of this kind.

Valves, or seats, of this rubber-like polymer have become attractive because they seal very well with only a small amount of force between valve and seat; foreign matter does not often cause leakage; and, engine vibration does not disturb valve sealing to the same extent as on interengaging metal surfaces. Of course, the use of rubber depends upon elimination of certain inherent disadvantages, such as sticking between valve and seat, minor swelling, friction between rubber and metal, and lack of rigidity in the rubber which would allow a rubber valve to flex suiicient to leak. Besides avoiding the above disadvantages, a rubber valve should be so constructed as to be self-centering to some extent, at least;

tiltable to effectuate full, complete, seating; and, be foolproof in assembly or use as well as inexpensive to manufacture.

Tests have shown that a valve constructed, according to this invention, has all of these qualifications. This valve comprises three separable elements, a cage, or body, a valve, and an operating plunger. The cage is a metal piece (preferably brass) with an internal cylindrical barrel, a threaded extension on the barrel to form a nipple part integral therewith, and an inlet passage formed through the nipple and opening in the barrel. An annular. raised valve seat surrounds the inlet passage opening in the barrel and is substantially concentric therewith.

The plunger element is a metal piece (preferably aluminum) and is a rod of polygonal round, or triangular, cross-section constructed to have a sliding fit in the barrel of the cage element. Opposite ends of the rod are convex, sort of rounded cone-shape. As the plunger is independent of both the valve and cage, lateral plunger movement in theA barrel is allowable without disturbing the seating of the valve. i

The valve element includes a holder with a rubber like center. This holder isv a short metal tube (preferably aluminum) of polygonal, round, or triangular, crosssection, or a plastic tube of the same configuration' constructed to loosely fit in the barrel of the cage element.

The end surfaces of the valve holder are plane, and it is centrally apertured. Fixed Within the central aperture of the valve holder is a rubber insert. In other words, the valve element might be described as a nut-shaped valve holder With a rubber center. The valve holder is rigid in external shape; is readily slidable in the metal barrel; and is so constructed as to be self-centering At the same time, the opposite exposed seating surfaces of the valve are rubber and it is itself reversible in the forms hereinafter described. So also is the plunger. This means that the parts cannot be assembled improperly. This particular valve element is not only useable with the cage element and plunger element, above described, but is also adaptable to different constructions and combinations of valve elements as this `description will here- Y inafter explain.

material are also known in oat valves, as shown by Berge, 2,525,014, and such a valve was once used in a Carter carburetor, illustrated in a Mechanics Manual, Willys Utility Vehicles 194653, Willys Motors, Inc., Toledo 1, Ohio (pages E118 and E119).

None of these priorstructures, however, whether used in a float type, ork a diaphragm type, carburetor, or other devices, have the same valve elements as above described, and none have the same advantages. It is believed that the valve, according to this invention, represents an improvement in a carburetor valve because, when in open position to admit a ilow of fuel, it rotates on the end f the Vplunger element and changes position with respect to the seat. If there is a particle of foreign matter trapped on its surface, it is very unlikely to be located between valve and seat on valve closing, and it is also likely it will be washed away before it can cause seating trouble.

It is the primary object of this invention to provide a valve assembly which eliminates flooding of the carbu retor fuel bowl Whether the engine is operative or inoperative.

It is still another object of this invention to provide seating surfaces for the valve assembly of a carburetor float valve, one of which is rubber.

It is a further object of this invention to eliminate the disadvantages `of swelling in the use of a rubber valve or seat in a carburetor oat operated valve.

It is still another object of the invention to eliminate friction due to the sliding action between rubber and metal parts in a float valve for a carburetor.

It is still another object of this invention to lend rigidity to a rubber valve or rubber valve seat and prevent exing of the rubber when used in a oat valve for a carburetor.

It is still another object of this invention to provide Y a rubber valve which is self-centering to some extent and tiltable and rotatable to effectuate sealing contact with the valve seat in the oat valve for a carburetor.

The following is a full, clear, concise and exact description of the invention when taken in conjunction with the illustrations in the accompanying drawings in which:

FIG. 1 is an exploded View in perspective illustrating the paIts of the float valve according to this invention;

FIG. 2 is a transverse vertical section of the cage element shown in FIG. 1;

FIG. 3 is an end view of the cage element shown in FIGS. 1 and 2;

FIG. 4 is an end view of the holder for the rubber valve;

. FIG. 5 is a side view of the holder for the rubber valve;

FIGS. 6 and 7 are end and side views, respectively, of the rubber insert which goes in the holdershown in FIGS. 4 and 5;

FIG. 8 is a side elevational view of the plunger element shown in FIG. 1;

FIGS. 9 and 10 are environmental views schematically illustrating the fuel bowl of a carburetor and showing a valve assembly according to this invention installed for operation by the float and float arm;

FIG. 11 is an environmental view schematically illustrating a fuel bowl for a carburetor and illustrating another possible manner of using the valve element according to this invention;

FIGS. 12 and 13 are transverse sectional views of a valve cage of standard type showing replacement parts applied to adopt the standard valve cage to the valve constructed according to this invention; and

FIG. 14 is a transverse section of a valve and valve cage similar to that shown in FIG. 1.

The valve cage element 10, shown in FIG. 1, is formed of a hexagonal piece of brass stock which is countersunk to form a cylindrical barrel 11, as shown in FIGS. 2 and 3. The hexagonal body 10 has a nipple end 12 integral therewith and may be threaded at 13. Extending through the nipple 12 and opening into the barrel 11 is a fuel passage 15, shown best in FIGS. 2 and 3. Surrounding the opening of the fuel passage 15 into the barrel 11 is an annular raised valve seat 16. Preferably, the valve seat 16 is a continuation of the fuel passage 15 and of the same size. Valve element 20 is a shorttube 21 of polygonal cross-section, preferably, formed from metal or plastic, which is centrally apertured at 22 to -receive a rubber plug, such as 25, all as shown in FIGS. 1 and 4 through 7, inclusive. Externally the valve holder, indicated as 21, is constructed to have a loose slidingfit within the barrel 11, and during movement therein will be guided for sliding by the corners of the polygonal nut-shaped valve holder.

The plunger 30 is a polygonal shaped rod-like membed dimensioned to have a sli-ding tit in the barrel 11, and is provided with

convex ends

31 and 32 which are of rounded cone-shape, as indicated in FIG. 8. Both the valve holder 20 and the plunger 30 are shown as hexagonal in cross-section, but it is contemplated that other shapes are equally suitable.

Turning now to FIG. 9, therein shown more or'less schematically is the fuel bowl of a carburetor, indicated here as 40. Within the fuel bowl is a fuel chamber 41 which contains a float 42 attached to a oat arm 43. Pivot 44 in a lug 45 cast into the side wall of the oat bowl pivotally mounts the arm 43 forswinging movement as the float 42 raises and lowers in response to fuel level, indicated as 47. These swinging movements of the oat arm 43 are directly transmitted to the plunger 30 causing the plunger to move outward in the barrel 11 as the fuel level 47 drops and inward into the barrel 11 as the fuel level 47 increases. The present position of the parts is exaggerated since the. fuel level is probably below any actual operating condition. However, such a level could exist after the engine has been inactive over a substantial period of time. In the position of the parts, the valve is removed from the seat 16, and fuel coming in the inlet 48 from the fuel pump can pass through the standpipe 49 and inlet passage 15 past the hexagonal or polygonal valve holder 21 and into the fuel bowl 41 past the polygonal shaped plunger 30. Alternatively, the fuel may pass through holes 17 in the walls of the barrel 11.'A's the plunger 30 rises in response to increase in fuellevel, the rubber center forming the valve engages the seat 16. Configuration of theV end 31 of the plunger 30 permits the valve 20 to tilt and to iind its own center on the seat 16. When the valve 20 is closed, the area exposed to pressure is no greater than the area of the wfuel passage 15. It makes no difference which side of the valve 20 is disposed toward the seat 16, nor, does it may any difference which end of the plunger 30 operates against the valve 20. The assembly, therefore, is foolproof. In the position of the valve 20, illustrated in FIG. 9, the area of valve opening is many times that of the area of the fuel passage 15, and it will be realized that only a slight drop of the valve 20 is necessary to fully open the passage 15. The valve element 20 may be a nut with a fixed rubber center formed by pressing in a rubber plug 25, which may be readily stamped out of a synthetic rubber. Any amount of swelling of the rubber insures a tighter fit between the plug 25 and the valve holder 21.

FIG. is a schematic illustration of a fuel bowl for a carburetor of a different type in which the valve `as sembly is horizontal. In this View, the fuel bowl 50 has a oat chamber 51 within which is the oat 52 attached to the float arm 53. A lug 54 cast in the inner wall of the fuel bowl 50 carries a pivot 55 for hinging the float arm 53. Bracket 56 is riveted to the float arm 53 by rivet 57 and projects upwardly to operate against the end 32 of the plunger 30. Fuel is admitted to the carburetor fuel bowl 50 through a threaded opening 58 which is connected to the fuel pump of the engine. The fuel ows through the inlet 58 past the valve 20 and plunger 30 into the -fuel bowl or alternatively through the passages or holes 17 in the cage 10 into the fuel bowl. The position of the parts shows the valve in full open position. During closing, the valve will rock upon the corners of the holder 21, and also slide into a position so that the rubber center of the valve 20 will center on the seat 16. The action of the parts of the valve in response to float movement is substantially the same as those above described with reference to FIG. 9.

FIG. l1 is a schematic illustration of a fuel bowl 60 for a carburetor. Within the oat valve is a float chamber 61 containing a float 62 operating a float arm 63. A lug 64 cast integrally with the inner surface of the fuel bowl mounts a pivot 65 upon which the arm 63 is hinged. A bracket 66 riveted to the arm 63 at 67 carries a valve holder and operator, generally indicated as 69. The holder is part of the bracket 66 and is of sheet metal corrugated to form a round conical point, such as 70, generally centrally located with respect to the rubber plug 25 in the holder 21 of the valve 20. Also integral with the bracket 69 are a plurality of fingers, such as 71, 72 and 73, loosely retaining the valve 20 in the bracket 69. The Valve 20 operates to and from a seat 116 surrounding a fuel passage 115, both of which might be integral with the wall of the fuel bowl or formed as shown in a nipple 112 screwed into the Wall of the carburetor fuel bowl. The threaded connection 75 is the inlet connection for the fuel delivered by the fuel pump or by gravity. The operation of the device shown in FIG. l1 is similar to that described in FIGS. 9 and 10.

The valve assembly described and illustrated with reference to FIG. 1 through FIG. 10, inclusive, is intended as a replacement for conventional needle valves and seats now used and may be sold with the parts thereof packaged together. However, it is contemplated that the valve element 20 might be sold separately for use with conventional needles and seats.

It is also possible to convert needle valve cages which are new or worn to receive a valve assembly according to this invention and so restore satisfactory operation for the float valve assembly as a whole. Necessarily, the valve assembly for such a conversion will take a slightly different form or forms from those heretofore described. Examples of these slightly different forms are shown in FIGS. 12 and 13.

For example, with reference to FIG. 12, a valve cage 135 is shown of the type which screws into a threaded boss in the inlet to a fuel bowl of a carburetor from the outside of the bowl rather than from the inside as do the prior described constructions. In this type of valve cage, as illustrated generally at 135, a threaded socket 129 is provided for receiving the nipple on the end of 6 the fuel line connection from the fuel pump. The threaded portion 130 on the outside of the barrel or cage screws into the threaded boss in the fuel bowl inlet of the carburetor, and normally the usual form of fuel valve which is a steel needle, for example, operates within the barrel. The conversion kit to adapt this :barrel 135 to the use of a valve according to this invention includes, for example, a washer 128 which fits within the barrel and has a central passage. The Washer is held in place by a titting 127 with a fuel passage 137 which has a pressed fit within the barrel 135. On the upper end of the passage 137 is an annular valve seat 126.

The valve assembly 120 which is used in this modification has a holder 121 constructed as heretofore described of metal or plastic. Within the holder is a rubber plug 125 with opposite convex surfaces. The valve assembly 120 is held -within the valve cage by staking over the edges 131 at the outer end of the cage. By constructing the rubber plug in this manner, either side may be used against the seat 126, and the valve is reversible and foolproof in installation. Whichever side is used as the valve, the opposite side being convex and projecting beyond the edges 131 is adapted for contact with the oat arm lever so as to operate the valve 120 toward and away from the seat 126.

The above description of the valve cage, generally indicated as 135, will also serve as a description for the same cage shown in FIG. 13. The difference between the modification in FIG. 13 and that in FIG. 12 heretofore explained is merely in the valve assembly therein indicated as 220, and the foregoing description will not, therefore, be repeated. The valve assembly 220 has a holder 221 constructed in the same manner as that shown in FIG. 12. Within the holder 221 is a rubber plug with opposite facing cone-like surfaces 225, either one of which will operate on the valve seat 126 so that the valve assembly 220 is reversible and thereby foolproof. Whichever surface of the valve assembly 220 is used as the valve, the opposite surface is adapted to be operated by the float arm lever.

In operation, the two modifications in FIG. 12 and FIG. 13 are alike. To convert from the conventional needle valve to the nut-like valve according to this invention, it is necessary to remove the cage from the fuel bowl and the fuel line and replace the needle with the fitting 127. Washer 128 will insure a gasoline tight joint beneath the fitting and between the fitting and the cage 135. The valve assembly either 120 or 220 is then dropped in and the edge of cage 131 staked over so as to prevent the valve assembly from falling out of 'the cage. The cage 135 is then replaced in the wall of the fuel bowl and the fuel line connected.

FIG. 14 shows a form of valve similar to that shown in FIG. 1, having the same features as therein shown and heretofore described. This description Will not be burdened with a repetition of the description of the same structure, but will be restricted to the differences. Like reference characters will be used to indicate like parts to those heretofore described in FIG. 1.

lIn this modification, the fuel passage 15 can be smaller than the valve seat 16 to suit the requirements of a particular carburetor. It is contemplated that the size of the valve seat 16 remains at a constant size regardless of the required size of the fuel passage 15. Otherwise, the valve cage is the same as that shown in FIG. 1. Plunger 30 is also constructed as described with reference to FIG. 1, but the valve element differs. The nut-like holder 321 in this modification is a round nut, or ring, with a round hole.

Inturned flanges

326 and 327 retain the plug 325 of rubber-like material tightly in the nut 321. On opposite faces of the plug 325 are cylindrical bosses 336, one of which projects into and nearly fills the hole in the valve seat 16 leaving only the small clearance space 335 between the outside of thevboss 336 and the hole in the seat 16. In order to assure that boss 336 will enter the seat 16 without interference, it is necessary to have the clearance between the outside of the nut 321 and the bore 11 of the cage less than the clearance 335 and also to have the plug 325 held tightly in the nut 321. In this modification, as in FIG. 1, the valve and plunger are reversible end for end and both have opposite sides, or ends, which are the same. When the valve is open, the flow of fluid causes plug and holder to rotate on the end of plunger 30 just as in the other modifications where the valve is installed in -a Vertid cal position. It has not as yet been positively proved if the degree of rotation is as great when the valve is installed horizontally. The valve is also rockable on the plunger as in prior modifications.

This'modied form of valve in FIG. 14 has another feature which does distinguish its operation from the others. It may be characterized as a valve which produces a very gradual opening with respect to valve travel. Until the boss 336 is clear of the seat 16, ow of fluid is confined to the clearance space 335. This is the control point of the valve rather than the distance of the valve off of seat 16. Until the boss 336 moves out of the seat 16, the pressurized fluid in the line between the fuel pump and the valve is compelled to pass through clearance space 335 as the valve moves olf its seat and then between the face of the valve 325 and the edge of seat 16. Thus, there are, on initial opening, two restrictions in the valve to throttle the liow of fuel into the carburetor. As the valve opens still further, of course, the space between the face of the valve 325 and seat 16 become progressively larger until the boss 336 is withdrawn to eliminate the restricting eiect of clearance 335.

Now this ow restricting effect inherent in the valve of FIG. 14 has been found very advantageous iu certain installations. The reasons Why this is so have not been positively ascertained, but the favorable results confirm the suspicion that the valve of rubber-like material has so improved the shut olf characteristic in fuel inlet valves, that, as a result, a new problem has been created. In other words, vapor pressures in the fuel lines are merely creating a different problem than heretofore because the rubber-like valve is more successful than the steel needle and seat has been in retaining those pressures.

The iirst indication of this was that when the rubberlike valve was substituted for the metal valve to give better control of fuel supply to the carburetor, the substitution eliminated all prior complaints on stalling due to flooding at normal engine idle speeds, on rapid braking, and on sharp turns. However, much later, a new complaint was received. It seemed that after a normal engine start, the engine would stall when the throttle was opened suflicient to obtain power. This complaint occurred infrequeutly, but with the same make of automobile and often enough to require close investigation. It usually occurred after the highly Volatile fuels for winter use came on the market for supply for winter driving. It usually occurred during a warm spell of weather and after the engine was fully warmed up to operating temperature. When test equipment was installed, it was found that it was not unusual, when the engine stopped, for the pressure in the line between pump and valve to increase from the normal 31/2 pounds pressure range to l2 pounds within a few minutes after stopping the engine. It was also discovered that after a normal restart of the engine, that, on opening the throttle to obtain power, this pressure dropped very rapidly to below normal and the engine stalled. The faster the throttle was opened the quicker the stall. When a restriction was placed in the outlet from the fuel line, this eiected a temporary cure.

From these facts, it was deduced that opening the throttle of the carburetor enough to obtain power dropped the fuel level enough to immediately open the fuel inlet Valve a significant amount. There then followed a blast of gas at high velocity into the carburetor which was blowing some of the liquid fuel in the carburetor through the nozzles, or vents, into the engine intake. The blast of gas thereby produced an excessively rich mixture in the engine intake which on reaching the cylinders was too rich to burn.

Since the engine could not tolerate a permanent restriction at the outlet of the fuel line, various other ideas were tried, but the simplest approach has been the valve of rubber-like material with the features described in FIG. 14, and this has so far appeared to be a satisfactory solution. As this valve begins to open, there are present two restrictions to throttle the discharge, one being at the clearance 335, the other being between the valve face and the seat. It is reasoned that acting together, or separately, these two restrictions slow the gas discharge to a degree which the carburetor vents can dissipate without upsetting ca-rburetor calibration to a degree producing a stall. It has been definitely established that sudden fuel inlet valve opening is not always desirable. The embodiment in FIG. 14 is merely one of several ways of avoiding sudden valve opening.

Other changes in and modifications of the construction described may be made without departing from the spirit of my invention or sacriicing its advantages.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In a carburetor having a fuel bowl, a fuel inlet to said bowl, a valve mechanism controlling said fuel inlet, and a oat operatively connected to said valve mechanism for actuating the same. in response to changes in fuel level in said bowl; the improvement in said valve mechanism comprising,

(l) a valve body,

(2) a passage in said valve body forming a part of the fuel inlet to the fuel bowl,

(3) a valve seat around one end of said passage,

(4) a float operated reversible valve element cooperating with said valve seat, said valve element being a plug of iieXible and resilient rubber-like material with a minimum diameter greater than said seat to provide end faces on said plug, either of which is adapted to engage said seat and close said inlet,

(5) relatively rigid means provided with an aperture in which the outer periphery of said plug tightly iits to limit flexing of said plug, said valve element and rigid means constituting a reversible unit,

(6) actuator means separate from said valve providing a rockable support for said plug relative to said seat, and

(7) means guiding said valve toward and away from said seat located in spaced relation to said means to limit flexing of said plug and separate therefrom.

2. In a carburetor having a fuel bowl, a fuel inlet to said bowl, a valve mechanism controlling said fuel inlet, and a float operatively connected to said valve mechanism for actuating the same in response to changes in fuel level in the bowl; the improvement in said valve mechanism comprising,

(1) a valve body,

(3) a valve seat around one end of said passage,

(4) a oat operated reversible valve element cooperating With said valve seat, said valve element being Va plug of exible and resilient rubber-like material with a minimum diameter greater than said seat to provide end faces on said plug, either of which is adapted to engage said seat and close said inlet,

(5) relatively rigid means provided with an aperture in which the outer periphery of said plug tightly tits to limit flexing of said plug, said valve element and rigid means constituting. a reversible unit,

(6) means separate from said valve and operated bythe iioat and contacting with the surface of said plug on the opposite side from said seat for rockably supporting said valve with respect to said seat, and

(7) means for guiding said valve toward and away from said seat located in spaced relation to said means to limit flexing of said plug and separate therefrom.

3. In a carburetor having a fuel bowl, a fuel inlet to said bowl, a valve mechanism controlling said fuel inlet, and a float operatively connected to said fuel valve mechanism for actuating the same in response 'to changes in fuel level in the bowl; the improvement in said valve mechanism comprising,

(l) a valve body,

(3) a valve seat around one end of said passage,

(4) a float operated valve cooperating with said valve seat, said valve being a plug of flexible and resilient rubber-like material with a minimum diameter greater than said seat,

() a nut-like holder surrounding the outer periphery of said plug to limit flexing of said plug,

(6) means separate from said valve operated by the float contacting with the surfaceof said plug on the opposite side from said seat for rockably supporting Said valve with respect to said seat, and

(7) a valve guide separate from said valve and lastnamed means and said nut-like holder, said guide slideably mounting said valve supporting means, said guide surrounding said nut-like holder and being sufliciently larger than said nut-like holder to provide free valve movement in any direction.

4. In a carburetor having a fuel bowl, a fuel inlet to said bowl, a valve mechanism controlling said fuel inlet, and a float operatively connected to said valve mechanism forl actuating the same in response to changes in fuel level in the bowl; the improvement in said valve mechanism comprising,

( 1) a valve body.

(2) a passage in said valve body forming a part of the fuel inlet in the fuel bowl,

(3) a valve seat around one end of said passage,

(4) a float operated valve cooperating with said valve seat, said valve being a cylindrical plug of flexible and resilient rubber-like material with end surfaces of greater diameter than said seat to form a reversible valve,

(5) means surrounding the outer periphery of said plug to limit flexing of said plug,

(6) a valve operator separate from said Valve and providing arocking support therefor, and

(7) a valve guide separate from said valve, said support, and said means to limit flexing of said valve, said guide slideably mounting said valve operator, said guide surrounding said means to limit flexing of said valve and being sufficiently larger than said means to provide for free valve movement.

5. In a carburetor having a fuel bowl, a fuel inlet to said bowl, a valve mechanism controlling said fuel inlet, and a float operatively connected to said valve mechanism for actuating the same in response to changes in fuel level in the bowl; the improvement in said valve mechanism comprising,

(l) a valve body,

(3) a valve seat around one end of said passage,

(4) a float operated valve cooperating with said valve seat, said valve being a cylindrical plug of flexible and resilient rubber-like material with end surfaces of greater diameter than said seat to form a reversible valve providing end faces on said plug either of which is adapted to engage said seat and close said inlet,

(5) a nut-like holder surrounding the outer periphery of said plug to limit flexing of said plug, said valve element and holder constituting a reversible unit,

(6) means separate from said nut-like holder and operated by the float contacting with the surface of said plug on the opposite side from said seat for rockably supporting said valve with respect to said seat, and

(7) guide means separate from said means to provide freedom for Valve movement in any direction.

6. The combination defined in claim 5 in which the end surfaces of greater diameter than the seat on said plug are convex and project from said nut-like holder.

7. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel inlet passage opening into said fuel bowl and an annular valve seat surrounding said outlet, the improvement comprising,

(l) a reversible valve element in said assembly including a plug of flexible and resilient rubber-like material having end faces on said plug either of which is adapted to engage said seat and close said outlet, and a hollow nut-like holder around said plug constructed to lend rigidity to said plug, said plug being held securely in said hollow nut-like holder,

(2) valve actuator means separate from said valve element and operated to move said valve element onto said seat in response to an increase in the amount of fuel in said bowl,

(3) a convex surface on said valve actuator means to support said valve element on said actuator means when said valve element is off said seat and permit rotation of said valve element by fluid flow into said fuel bowl, and

(4) means around said holder for guiding the end face of said plug onto said seat.

8. The improvement defined in claim 7 in which, said hollow nut-like holder exposes opposite ends of said plug, and opposite end faces of said plug are adapted to engage said seat and close said outlet, so that, said valve element is reversible.

9. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel passage opening into said fuel bowl, and an annular valve seat surrounding said outlet, the improvement comprising,

(l) a reversible valve element including a cylindrical plug of flexible and resilient rubber-like material with a minimum diameter greater than that of said annular Valve seat to provide end faces on said plug adapted to engage said seat and close said outlet, and a nut-like holder constructed to lend rigidity to said plug and having a round hole in which said cylindrical plug is coaXially disposed and tightly held,

(2) Valve actuator means separate from said valve element and operated to move said valve element onto said seat in response to increase in the amount of fuel in said bowl,

(3) means forming a rockable support for said 'valve element on said actuator means, and

(4) means loosely caging said valve element to cause seat engagement by an end face of said plug when said actuator operates said valve element.

10. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel inlet passage opening into said fuel bowl, and an annular valve seat surrounding said outlet, the improvement comprising,

(l) a Valve element in said assembly including a plug of flexible and resilient rubber-like material having an end face adapted to engage said seat and close said outlet, and a hollow nut-like holder around said plug constructed to lend rigidity to said plug, said plug being held tightly in said hollow nut-like holder,

(2) valve actuator means in the form of a plunger operated by changes in the amount of fuel in said bowl and separate from said valve element, said plunger having opposite ends rounded to provide a structure reversible with respect to said valve element and a support for said valve element on the end of said plunger engaging and rotatably supporting said valve element, and

(3) means separate from said Valve element and plunger and surrounding the sides of both to form a guide in which said plunger is slidable and a chamber between the end of said plunger and said seat in which said Valve element is free to move a limited amount in any direction when open.

11. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel passage opening into said fuel bowl, and an annular valve seat surrounding said outlet, the improvement comprising,

(l) a reversible valve element including a cylindrical plug of exible and resilient rubber-like material with a minimum diameter greater than that of said annular seat to provide end faces on said plug adapted to engage said seat and close said outlet, and a nut-like holder constructed to lend rigidity to said plug and having a round hole in which said cylindrical plug is coaxially disposed and tightly held,

(2) Valve actuator means in the form of a plunger operated by changes in the amount of fuel in said bowl and separate from said valve element, said plunger having opposite ends rounded to provide a structure reversible with respect to said valve element and a rockable support between said valve element and the end of said plunger engaging said valve element, and

12. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel passage opening into said fuel bowl, and an annular valve seat surrounding said outlet, the improvement comprising,

(1) a reversible valve element in said assembly including a cylindrical plug of eXible and resilient rubber-like material having end faces either of which is adapted to engage said seat and close said outlet,

(2) valve actuator means engaging the opposite end face of said plug, and

(3) a convex surface on said valve actuator means to support said valve element on said actuator means when said valve element is o said seat and permit rotation of said valve element by iluid flow into said fuel bowl and freedom of movement in all directions.

13. In a valve assembly for a fuel inlet to a fuel bowl of a carburetor, said assembly having -a valve body with a fuel inlet passage connected at one end to the fuel inlet of said fuel bowl, an outlet at the other end of said fuel passage opening into said fuel bowl, and an annular valve seat surrounding said outlet, the improvement comprising,

(2) valve actuator means for moving'said plug to engage said end face on said seat, and

(3) means between said valve element and said seat acting to restrict the amount of opening produced by initial movement of said end face away from said seat,

(4) a convex surface on said actuator means and engaging said valve element to support said valve element on said actuator means when said valve element is off said seat and permit universal movement of said valve element by fluid ow into said fuel bowl.

References Cited UNITED STATES PATENTS 372,641 11/1337 Robertsh-aw 251-36 732,871 7/1903 Lemp 137-329.04 2,065,087 12/1936 May 137-434 X 2,078,567 4/ 1937 Foregger 251-121 X 2,258,271 10/ 1941 Walter 137-439 2,525,014 10/1950 Berge 137-418 2,710,163 6/ 1955 Mueller 251-85 2,752,937 7/ 1956 Hieger 137-434 2,869,578 1/ 1959 Crockett 137-444 2,890,711 6/ 1959 Parker 137-434 2,946,343 7/1960 Sterrett 3 137-443 X FOREIGN PATENTS 639,869 1936 Germany. 623,905 of 1949 Great Britain.

WILLIAM F. OD-EA, Primary Examiner.

R. GERARD, Assistant Examiner.

Claims

1. IN A CARBURETOR HAVING A FUEL BOWL, A FUEL INLET TO SAID BOWL, A VALVE MECHANISM CONTROLLING SAID FUEL INLET, AND A FLOAT OPERATIVELY CONNECTED TO SAID VALVE MECHANISM FOR ACTUATING THE SAME IN RESPONSE TO CHANGES IN FUEL LEVEL IN SAID BOWL; THE IMPROVEMENT IN SAID VALVE MECHANISM COMPRISING, (1) A VALVE BODY, (2) A PASSAGE IN SAID VALVE BODY FORMING A PART OF THE FUEL INLET TO THE FUEL BOWL, (3) A VALVE SEAT AROUND ONE END OF SAID PASSAGE, (4) A FLOAT OPERATED REVERSIBLE VALVE ELEMENT COOPERATING WITH SAID VALVE SEAT, SAID VALVE ELEMENT BEING A PLUG OF FLEXIBLE AND RESILIENT RUBBER-LIKE MATERIAL WITH A MINIMUM DIAMETER GREATER THAN SAID SEAT TO PROVIDE END FACES ON SAID PLUG, EITHER OF WHICH IS ADAPTED TO ENGAGE SAID SEAT AND CLOSE SAID INLET, (5) RELATIVELY RIGID MEANS PROVIDED WITH AN APERTURE IN WHICH THE OUTER PERIPHERY OF SAID PLUG TIGHTLY FITS TO LIMIT FLEXING OF SAID PLUG, SAID VALVE ELEMENT AND RIGID MEANS CONSTITUTING A REVERSIBLE UNIT, (6) ACTUATOR MEANS SEPARATE FROM SAID VALVE PROVIDING A ROCKABLE SUPPORT FOR SAID PLUG RELATIVE TO SAID SEAT, AND (7) MEANS GUIDING SAID VALVE TOWARD AND AWAY FROM SAID SEAT LOCATED IN SPACED RELATION TO SAID MEANS TO LIMITING FLEXING OF SAID PLUG AND SEPARATE THEREFROM.