US1534212A - Carburetor - Google Patents

Description

April 21, 1925.

W. C. HESS CARBURETOR Filed March 2, 1923 2 Sheets-sheet l1 ilfamnmlnummmm IZIH April 21, 1925.

Filed March 2, 1923 2 Sheets-Sheet 2 l Patented Apr. 21, 1925.

UNITED STATES PATENT OFFICE.

WILLIS c. nnss, or DETROIT, MICHIGAN. Y

CARBUBETOR.

Application led Harch 2, 1923. Serial, No. 629,408.

To all whom it may concern.'

Be it known that I, WILLIS C. Hnss, a citizen of the United States of America, and a resident of Detroit, county of Wayne and State of Michigan, have invented certain new and useful Improvements in Carburetors, of which lthe following is a full and clear specification.

The object of this invention is to provide simple automatic means whereby, after the feed-valve is manually set, the amount ot' fuel delivered into the atomizing-chamber will be at all times properly proportioned to the amount of air drawn thereinto at whatever speed the motor may be running, to thereby promote economy as well as smooth running of the engine at all speeds. There are other minor objects which will appear in the course of the following speciication.

This application is a. substitute in part for my copending application Serial No. 321,901, filed September 5, 1919.l

Fig. 1 is a side elevation with the inletpipe partly in section and the cover of the governor device removed;

Fig. 2 is a vertical sectional view;

Fig. 3 is a view partly in section showing the under side of the automatic `feed-device;

Fig. 4 is a detail end View ofthe automatic feed-device, the pressure vane being shown in transverse section;

Fig. 5 is a vertical sectional view taken at right-angles to the line of lthe 'section in which Fig. 2 is taken;

Figs. 6to 9, inclusive, are views of details hereinafter described:

In the drawing, a desi ates the airinletpipe of the mixingcham er which is adapted to be closed by a strangler-valvev b .com4

sisting of a convolute wire-spring conical inl shape and having its apex extending into the inlet-pipe while the base-coil of the cone rests on the outer end of the intake. Normally the coils are in Contact with each other, but 'they are not in air-tight contact, so that a limited amount of air will pass intoythe intake between the coils. To close the coils tightly a ainst each other and thus practically shut o all inlet of air, I provide means for bringing pressure to bear on the apexof the coil, this means in the present instance consisting of a rod c extendin through the coil at the apex and provid with a nut-collar d, a suitable bell-crank The nut-collar d is threaded on the stem c vfor purposes of adjustment. It will be understood that thebell-crank arrangement 6 is adapted to be o erated from the drivers seat of the vehicle 1n the usual manner.

In the outlet-end of the mixing-chamber is arranged the usual buttery valve z which controls the amount of mixture which passes to the engine. The fuel supply is delivered' into the mixing-chamber through the medium of a flat vane z' afiixed to a rock-shaft j extending transversel of the mixing-chamber and journaled at in the opposite walls thereof, the side edges of the vane z' fitting against the` vertical straight side-walls Z of the mixing-chamber. The vane extends from the shaft j toward the butterfly valve, i. e., in the direction of the current of air, so that the air current will tend to swing the vane upwardly and thus increase the area of the air-inlet. The rock-shaft j is hollow and its interior is connected by means of a long narrow slot m with a flat narrow space n formed in the vane and extending approximately the full area thereof, this space n being open along the entire free edge of the vane so that the fuel is4 delivered in a thin film oli' said free edge of the vane directly into the bod of the ingoing air current, wher( by the uel will -be ensured of a line commi nution and thorough mixing with the air before it reaches the engine. By delivering this fine film of fuel along the top of lthe .air current, it will be observed that large particles of the 1i uid fuel will have to pass entirely throng the air current before they reach the bottom of the mixing-cham ber, whereby I reduce to a minimum the chance of these heavy particles of fue] being deposited in the bottom of the conduit on the way to the engine, it being a defect in most carburetors that unatomize'd particles of fuel will collect in the bottom of thefuel conduit and final] reach the engine in a liquid form, there y not only rendering the running of the engine uneconomical but also interfering very materially with its smooth runnin One end of the hollow rock-sliaft j is open,

as at .0, and the suppl of fuel is conducted to this open end of t e shaft through the medium of a duct p which communicates at its lower end with the usual float-chamber, the fioat being arranged to maintain the level of the fuel in the conduitI p at a predetermined point below the inlet o.

In the hollow rock-shaft is housed a needle-valve which is adapted to be adlusted manua ly as well as automatically.

his needle-valve extends into the shaft from the end op osite the inlet o, and it is normally presse toward its seat iby means of av fiat spring -r, shown in Fig. 2. The position of the needle-point with reference to its seat in the shaft j is .determined by a nut s threaded on the outer end of the valvestem and ada ted to be screwed against a collarv t threa ed on the same stem between the nut s and the adjacent end of the shaft thxed to the shaft j at a point adjacent the collar t, by means of a clamp u, is an arm o which extends radially from the shaft y' and lies approximately parallel with the adjacent edge or' the vane z' but outside of the wall Z of the mixing-chamber. The parts s and are also outside of the mixing-chamber, these part-s being desirably enclosed in a removable casing fw, shown in Fig. 2, this casing and the aforesaid parts being aflixed to the mixing-chamber at the opposite side Jfrom the Hoet-chamber. lt will be understood that all the parts carried by the shaft j together with all the parte carried by the arm o (said latter carts being hereinafter described) rock with the shaft j whenever the vane z' is shiftedl by the incoming air current.

lt will be understood that the vane and its attached parts tend to swing downwardly hy gravity, but that in all positions of the vane the fuel-inlet o is open to the supplyconduit p. This tendency for the vane to swing downwardly and thus choke the inlet is resisted by a manually-adjustable device consistin of a set-screw threaded to a lug' y and loc ed by a lock-nut e, the end ot' the set-screw bein ada ted -to bear against a 'dat spring o' attlxed to the under-side of the free end of the arm o. The arm Av with its attached parts normally rests by gravity on thelaend of set-screw a. By adjusting the screw the position of the vane may be determined.k The devices 'are usually set so that the vane shall occupy a position nearly closed, that position being suflicient to supply enough air and fuel to run the engine at its lowest speed.k When the engineis accelerated, the inrushing air will swing the vane upwardly and thus increase the area of theinlet between the loweredge of the vane and the bottom wall of the mixing-chamber, and when the vane is thus automatically raised by air-pressure, I utilize this movement of the vane to increase the supply of fuel momentarily, so that at all times the predetermined proportions shall be maintained. These automatic devices consist of a weight d aixed to a pivot-.shaft e mounted in ears 'f' carriedby the aforesaid arm fo, collars g being aixed to. said pivot-shaft e to prevent endwise movement of the sha-ft 1n its bearin sf This weight d normally tends to s wm downwardly in an oblique directiom this enig due to the fact that the pivot-shaft e' is supported in nan oblique position, parallel with the arm fv, when the parts are in normal position. This wei ht rests gravitatingly against a bossk carried a lever d pivotally mounted in ears j carried by the lever u, the opposite (shorter) end of said lever i having a loose engagement with the aforedescribed collar t, so that when the longer (free) end ci the lever z" is swung toward its supporting bar o by means of the weight, theicollar t will be moved outwardly and carry with it the needle-valve and thus permit an increased supply of fuel to the spreading vane n. It is obvious that when arm u is suddenly swung upwardly, the weight d will, owing to its inertia, tend to stand still while the lever-arm o moves from its rest position,- this movement being due to the action of the inrushing current of air upon the vane z'. This inertness of the weight thus causes it to impose an excessive pressure on boss 7i" mo'- mentarily, thus causing the free end of the lever z" to be swung away Jfrom the inner side of the arcuate har 7u against which bar it is held normally in contact. The eiiect of this is to produce an additional supply of fuel momentarily, this Vbeing necessary when the throttle-butterfly is suddenly thrown open to permit an increased supply of air. ln such case. the incoming air 1s of decreased density and is therefore less effective in drawing the proportional supply of fuel in through the normal nozzle-opening. It is, therefore, the object` of the weight and `its peculiar manner of mounting to nio- Amentarily increase the fuel supply to compensate for the decreased suction power of the incoming air at the moment of opening the throttle. IThis increase in the area of the normal feed-opening needs to be but temporary, as the incoming air quickly assumes its normal density in the mixingchamber and is thereafter capable of pulling in the normal amount of fuel. This automatic temporary injection of additional fuel is important in that it makes it practicable to operate a carburetor efficiently on a normally lean mixture, thus eatly tending to eliminate carbon deposits 1n the cylinders of the engine and to also bring about a maximum of economy in the runningy of the engine.

Arcuate har k is adjustably mounted with in the casing fw in position to overlie static device consisting preferably in aixing the extended free end of lever i', so as to permit the lever to move in and out freely and yet form a guide or stop for the lever, a contacting lboss Z being formed'on the end of the lever 2 to reduce friction. This bar k restricts the outward swing of the lever i against the action of the aforedescribed spring a', which constantly presses against t e outer end of the stem of the valvel and thus serves to hold the needle-valve 1n its adjusted position against the tendency of said sprin r to close the needle-valve. It will be un erstood, however, that this arcuate bar k does not interfere with the free inward swing ofI the free end of lever z" under actionl of the weight d.

It will be observed that the bar k is mounted adjustably on three clam -screws k2 and that itis made of a thin iexi le strip of metal to enable it to be flexed or warped into any desired shape consistent with the functions it is intended to perform. In this way, the position of the needle-'valve g may be automatically controlledin action to give the required normal fuel-supply et any posi-Y tion of the pressure vane n, corresponding to any engine speed.

To maintain the conical sha e of the sprin -coil when pressed into c osed position, provide a plurality of fingers o which depend intothe coil and lie against the coilsi these fingers being carried by a ring p clamped on the top coil in any suitable manner.

The slight adjustments ofthe vane n to compensate for seasonal and other changes intemperature are vobtained by a thermoto the outer face of the lever a' a strip or bar p2 of sensitive metal of the well-known kind, whereby increase in temperature will warp the bar and thus tend to increase the openin of the valve. To steadythe movements o the vane n, I desirably atiix to its upper face a weight g and also provide a flat spring r for the same purpose, this spring being aiiixed to the wall of the casing in such position as to bear lightly down on the lever 'v at a suitable point, as shown in Fig. 1.

In the top end of the fuel channel fp, at a point above the normal level of the uel in the floating chamber, I provide a bleed opening the object of which is to prevent siphonic action emptying theiloat-chamber into the mixing-chamber. It has been found in practice that when the engine stops there is sometimes suicient fuel in the hollow valve hub j and the flat distributing chamber n in the vane to cause a si honic action that pulls gasoline out of the oat-chamber and empties it'into the mixing-chamber, tlns action' being particularly promoted by the fact that upon cessation of the inrush of air by the sto ping of the engine, the vane drops to normali closed position. The provision of this bleed opening will destro this siphonic action. It will be understoo that this opening is so small in diameter that the amount of air that will be drawn in through the openino' during the operation of the carburetor will not materially aii'ect the charge.

The nature and scope of the invention havin been thus indicated and its preferred embo iment having been specifically described, what is claimed as newis:

1. In a carburetor, a pressure-operated vane having a hub at its upper end, said hub having a passage extending axially through it communicating with a distributing-chamber in the vane extending to its lower edge,

said hub having journals which pivotally support the vane in the walls of the mixingchamber, means for supplying gasoline to one end of said hollow hub, and a needlevalve adjustably supported in the other end of said hub and adapted to control the inlet of fuel at the opposite, inlet end of the hub.

2. In a carburetor, a pressure-operated vane having a hub at its upper end, said hub having a passage extending axially through it communicating with a distributing-chamber in the vane extending to its lower edge,

said hub having journals which pivotally support the vane in the walls of the mixingchamber, means for supplying gasoline to one end of said hollow hub, a needle-valve adiustably supported in the other end of said hub and adapted lto control the inlet of fuel at the opposite, inlet end of the hub, and means mounted on the hub for momentarily increasing the opening of the valve when the vane is suddenly swung upwardly.

3. In a carburetor, a pressure-operated vane having a hub at its upper end, said hub having a passage extending axially through it communicating with a distributing-chamber in the vane extending to its lower edge, said hub having journals which pivotally support the vane in the walls of the mixing-chamber, means for supplying `gasoline to one end of said hollow hub, a

needle-valve adjustably supported in the other end of said hub and adapted to control the inlet of fuel at the opposite, inlet vend of the hub, and means mounted on the hub for momentarily increasing the opening of the valve when the vane is suddenly swung upwardly, said means consisting of an arm axed to the hub, a lever pivotally mounted on said arm and having one end in engagement with the needle-valve, and a weight pivotally mounted on said arm and normally restingl against said lever, for the purpose set fort 4. 'In a carburetor lof the class set forth, a swinging vanein the mixing-chamber having a free edge extending toward the outletend of the mlxing-chamber, said vane being provided with an interior chamber having .an outlet at the free edge of the vane to form the inlet nozzle forthe fuel, and means for supplying fuel to said chamber in the vane, said means embodying automatic devices `for increasing the supply of fuel momentarily only as the vane is suddenly' moved by the incoming air current, .for the purpose set forth.

sudden actuation of said member by incoming air, said means embodying a needlevalve, devices for operating the same by means of a weight, and devices whereby the pressure of the weight momentarily increases by inertia as the air pressure against said swinging member shifts the same.

7. In a carburetor, a pressure-actuated member in the mixing-chamber adapted to be moved by an increased flow of air therethrough, and means for automatically momentarily increasing the fuel supply as said member is suddenly shifted by increased air pressure, said means consisting of an arm adapted to be swung from an inclined position upwardly toward a horizontal position when said member is shifted, a weight pivotally mounted on said arm, and a fuel valve adapted to be opened by the inertia of said weight when the arm is swung upwardly.

'8. ln combination with a carburetor, a

swinging vane in the mixing-chamber and means connected thereto for actuating the fuel-feeding valve, said means being adapted to increase the supply of fuel momentarily only upon sudden opening of the throttle, said means embodying a swinging v arm carrying a pivoted lever, and a .Guide or confining bar in the path of said ever and against which said lever normally bears, said guide-bar being adapted to be dexed or warped.

9. ln a suction carburetor, a fuel-valve and devices for setting the same Jfor a ncrmal supply ot' fuel, a spring for holding the valve against further opening, and automatic means embodying a pressure-member `for momentarily opening said valve further against` the action of said spring during the initial inrush of air and causing the valve to be restored to normal without regard to the position of vthe pressure-member, said means embodying a swinging arm carrying a lever for actuating the valve, and a flexible guide-bar engaging said lever, for the purpose set forth.

10. In a carburetor, a vane in the mixingchamber having a fuel-distributing chamber and adapted to normally swing down to closed position and to be opened by inrushing air, said vane having a hollow hub, a fuel-valve controllin the inlet of 'fuel to said hollow hub, a oat-chamber connected to said hollow hub by a channel, a bleed opening being provided for said channel at a point above the normal level of the liquid in the Heat-chamber to thereby prevent siphonic action carrying fuel into the mixing-chamber after the" engine is stopped.

In testimony whereofr hereunto aix my signature.

WILLIS C. IESS.

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