US3007683A - Internal combustion engine carburetor improvements - Google Patents

Description

Nov. 7, 1961 v. B. MCCRACKEN 3,007,683

INTERNAL COMBUSTION ENGINE CARBURETOR IMPROVEMENTS Filed Apni 1, 1960 5 Sheets-Sheet l l5 i 79 69 J 6i 98 73 1 r 97 55 52 i 5 54 I 56 H I, 1% h I"? (I! W W "W h l I 1 1 W W I Q 53 Q 1 i 49 l I I INVENTOR Von B. Mc Crocken BY WWYW ATTORNEYS Nov. 7, 1961 v. B MOCRACKEN 3,007,683

INTERNAL COMBUSTION ENGINE CARBURETOR IMPROVEMENTS Filed April 1, 1960 5 Sheets-Sheet 2 INVENTOR Von B. McCrocken ATTORNEY5 Nov. 7, 1961 v. B. MCCRACKEN INTERNAL COMBUSTION ENGINE CARBURETOR IMPROVEMENTS 3 Sheets-Sheet 3 Filed Aprll 1, 1960 INVENTOR Von B. McCrccken ATTORNEY? States The present invention relates to improvements in carburetors for internal combustion engines and more particularly to the provision of a carburetor wherein the fuel component of the air-fuel mixture is metered into the stream of entering combustion air in progressively increasing amounts in predetermined relation to the engine induced air flow.

Standard carburetors of varying construction and design embodying varying pressure responsive fuel jet arrangements and fuel metering controls have heretofore been proposed for use on internal combustion engines, particularly those employed for propelling motor vehicles. The aim of all such devices is to supply the optimum fuel-air mixture at all engine speeds and to provide carburetor controls which will assure immediate variation in the supplied fuel-air mixture to increase or decrease engine speed at the will of the vehicle operator. For the most part, the prior art controls consists of: (1) a thermostatically controlled choke valve in the main airfuel entry passage near the air inlet end, (2) an operator actuated throttle valve in the air-fuel entry passage downstream from the choke valve adjacent the air-fuel mixture outlet end connection to the internal combustion engine, (3) an idling jet discharging into the air-fuel mixture outlet end beyond the throttle valve, (4) a series of venturi located between the choke and throttle valves, (5) low and high speed fuel supply jets leading respectively to the side of the air-fuel entry passage ahead of the series of venturis and the throat of the primary venturi, (6) a float chamber having passages supplying the various jets with fuel and connecting air bleedports leading to the air-fuel entry passage at spaced points to subject the fuel in the various jets to the differential pressure conditions along the air-fuel entry passage to effect a flow of fuel into the air stream in accord with the differential pressure existing along the air-fuel passage. In some cases, the modern automotive carburetors have superimposed upon such general carburetor arrangements surge pump arrangements operated upon depression of the throttle to pump a quick charge of fuel into the suddenly increased volume flow of air to eifect an instantaneous engine speed increase until the carburetor pressures effect a proper fuel-air mixture at the new throttle position. In other cases, it has been proposed to equip the operator controlled-valve with a metering pin to admit larger quantities of fuel as the high speed positions of the throttle valve are reached (United States Letters Patent 2,783,- 034 to M. E. I ones) or to introduce one or another form of governor controlled or pressure responsive metering pin and/ or air inlet valve arrangement into some more or less conventional form of carburetor to vary the supplied fuel component as the carburetor pressure conditions vary. Examples of such proposals are disclosed in the United States Letters Patent 2,572,169 to M. Mallory, 887,422 to I. 1. Power, 1,586,683 to F. C. Mock, 2,595,720 and 2,595,721 to C. R. Snyder, 2,601,975 to S. F. Hunt and 2,691,509 to E. Rivoche.

It is a primary object of the present invention to pro vide a carburetor that will be quickly responsive to the air-fuel mixture requirements of the engine at all times and at the same time vary the supply of fuel in accord with the flow variations of the entering combustion air.

A further important object of the present invention is to provide a carburetor made up of fewer and simatent O 3,097,583 Patented Nov. 7., 1961 pler parts to minimize parts production and maintenance problems and reduce costs While assuring optimum operating conditions throughout the full engine speed range.

A further object of the present invention is to pro vide an internal combustion engine carburetor wherein the fuel component is metered in accord with the volume of incoming combustion air and then supplied under pressure into the air stream through a series of fine openings located generally along a diameter of the air entry passage and arranged to spray fine streams of fuel in every direction into the entering air stream to effect entrainment of the fuel in the entering air stream and an eiiicient mixing of optimum quantities of air and fuel.

Still another object of the present invention is to provide the carburetor of the preceding object with a forminous air deflector vane disposed downstream from the fuel supply point in position to intercept at least a portion of the air and entrained fuel thereby creating an impact source and an area of extreme turbulence to effect a final thorough intermixture of the air and entrained fuel by vaporization and impact.

A still further object of the present invention is to provide a carburetor for use with an internal combustion engine with a metering fuel spray supply unit adapted to deliver a multiplicity of fine jets of fuel generally cross-wise into the entering air stream, an air deflector vane disposed along the path of travel of the entering air stream at a point downstream from the fuel spray supply unit to intercept a portion of the entering air stream and be deflected in accord with the impact force of the intercepted air stream and means interconnecting the deflector vane and the metering element of the fuel spray supply unit to automatically vary the amount of fuel metered to assure an optimum fuel air ratio as the air flow is increased or decreased in response to engine manifold requirements.

Another object of the present invention is to provide a'conversion attachment for use in converting a standard carburetor to a carburetor of the type defined by the preceding object.

Still further objects will appear from the following description and appended claims when read in connection with the accompanying drawings wherein:

FIGURE 1 is a perspective view of a carburetor embodying the present invention and made up from an existing standard carburetor and the conversion attachment provided by this invention;

FIGURE 2 is a side view of the carburetor of FIG- URE 1 as viewed from the backwardly facing side to the right of FIGURE 1;

FIGURE 3 is a side view of the carburetor of FIG- URE l as viewed from the other bacliwardly facing side of FIGURE 1 with the housing of the conversion attachment of FIGURE 1 in section to more fully illustrate the present invention;

FIGURE 4 is a fragmental sectional view taken on line 44 of FIGURE 2 with certain parts removed to illustrate the position assumed by the deflector vane during idling operation of the engine; and

FIGURE 5 is a fragmental sectional view taken substantially on line 5-5 of FIGURE 1 showing the manner in which the fuel supplied by the fuel pump divides ahead of the carburetor float chamber to flow under fuel pump pressure to the high speed metering valve of the present invention.

With continued reference to the drawings wherein like reference numerals are employed throughout the several views to indicate the same parts, carburetor 10 of the present invention as depicted in the drawings is made up from the main body 11 and intake manifold coupling section 12 of a standard 1954 Pontiac automobile carburetor and the high or power speed fuel supply mechanism or conversion attachment 13 of this invention. The supply mechanism or conversion attachment 13 is adapted to be secured to the inlet cover plate 16 of the conventional carburetor body 11 and provides an axial passage 17 forming the primary air inlet passage for the air required for forming a combustible fuel mixture and supporting combustion in the engine cylinders. It will be described in detail after the basic carburetor structure with which it is associated has been described.

Passage 17 in the illustrated carburetor directs the entering air downwardly to the air-fuel passage 18 (FIGURE 3) formed in main body 11 within the surrounding fuel filled float chamber 19. As best indicated in FIGURES l, 3 and 5, main body 11 midway of one side is provided with a well formation 21 (FIG- URE 1) opening inwardly into float chamber 19 (FIG- URE and adapted to receive a pair of spaced float support arms one of which is indicated at 22, depending from cover plate 16 adjacent upstanding fuel inlet boss 23 formed integrally on cover plate 16. The pair of spaced support arms 22 journal the opposite ends of pivot pin 24 freely supporting the centered pivot arm portion 25 of an oppositely extending float support arm 26 the ends of which are respectively welded to separate float elements 27 (FIGURE 3) disposed in the respective opposite ends of chamber 19 in well known manner.

Pivot arm portion 25 at its midpoint abuttingly engages the lowermost end of a needle valve 28 adapted to rise and fall with floats 27 and their support arm structure in response to variations in fuel level in chamber 19 to engage and disengage the valve seat of fuel inlet fitting 29 fixed in cover plate 16 in coaxial relation to the well 21. It will be appreciated, therefore, that fuel is admitted, to float chamber 19 only when needle valve 28 is unseated as a result of a fall in the level of the fuel in chamber 19. At all other times needle valve 28 engages the seat of fitting 29 preventing entry of fuel into chamber 19. To minimize entry of foreign matter into the float chamber and the carburetor passages supplied from the float chamber, boss 23 extends well above the upstanding tip '31 of fitting 29 andprovides an enlarged filter chamber 32 formed to support an axially extending screen filter 33 removable through the upper end of filter chamber 32 which is normally closed by a removable plug 34. The sidewall of boss 23 is drilled and tapped as indicated at 35 to receive an inlet fitting, to be presently described, provided to supply fuel from a fuel pump, driven by the engine in well known manner, to chamber 19 and the main fuel supply mechanism provided by this invention.

Main body 11 is suitably provided in conventional manner with one or more fixed idling jets 36 depending upon whether a single barrel or double barrel carburetor is desired. In this connection, the idling jets 36 preferably discharge into respective passages 37 leading to idling ports 28 formed in the Wall of that portion of passage 18 provided by manifold coupling section 12 and receive their supply of fuel from chamber 19 through riser chambers or passages 39 extending upwardly through chamber 19 and connected to chamber 19 through metering jets 41 in the bottom of chamber 19 (FIGURE 3).

Passage 18 is unobstructed throughout its length since the conventional venturi structure and main fuel supply jets and passages normally employed in the 1954 Pontiac carburetor used as a basis for the present illustration are not used being replaced by the main fuel supply mechanism of this invention to be presently described.

The intake manifold coupling 12 is provided in conventional manner with a venturi inlet passage forming an extension of passage 18 and equipped with the custornary operator controlled throttle valve 42 (FIGURE 2) carried by shaft 43 fitted at one end with a throttle rod actuator arm 44 and at its opposite end with a stop arm 45 carrying an adjustment screw 46. Screw 46 is threaded into spaced lugs 47 of stop arm 45 and is adapted to abuttingly engage an abutment screw 48 threaded into an integral lug 49 formed on the peripheral wall of coupling section 12. By means of adjustment screw 46 and air control needle valve 51, the closed position of the throttle valve 42 and the supply of metered air can be adjusted to assure optimum idling of the engine once the predetermined metered supply of fuel admitted through idling jets 36 is discharging from ports 37. It is to be noted, however, that the flow restricting high speed fuel supply venturi structure is wholly omitted assuring an adequate volume of free flowing air at all times.

The structure so far described in detail is conventional structure provided by the 1954 Pontiac or other carburetor structure to assure a supply of fuel and air for idling operation of an engine. It is intended to be merely exemplary of a suitable carburetor strlucture for supplying the idling requirements of an engine and does not of itself form a part of the present inventive improvement. It does, however, cooperate with the automatic engine responsive main fuel supply mechanism of the present invention and the customary acceleration pump housed in the chamber 52 and actuated from the throttle arm 44 through link 53 and actuator arm 54 secured to shaft 55 in conventional manner to provide a carburetor and fuel supply system for meeting the overall requirements of an engine from idling speeds to full power or full speed operation. Basically the present invention about to be described in detail contemplates an automatic metering of the main fuel supply to an engine which may be superimposed on an effective idling fuel supply and acceleration pump system either as an initial carburetor construction or an attachment for an existing carburetor, in this last usage the present invention being substituted for the existing power jets or speed jets of the existing carburetor.

With this point in mind and referring for the moment to FIGURES l, 2 and 5, the usual fuel inlet fitting in serted in tapped bore 35, is replaced by a T-connection 56 having the fuel pump supply hose 57 connected to its opposite end and a similar supply hose 58 connected to branch connection 59 and leading to the fuel metering assembly or fuel sleeve 61 of the present invention. As most clearly shown in FIGURE 3, fuel sleeve 61 is mounted adjacent the outer end of the cylindrical body housing 62 the mounting flange 63 of which is bolted to cover plate 16 by cap screws 64. Fuel metering sleeve comprises a sleeve-like valve body 65 extending diametrically across passage 17. The opposite ends of valve body 65 extend through suitable mounting apertures formed in diametrically opposed relation in the wall of housing 62 and are welded or otherwise fixedly secured therein as indicated by welds 66. One end of valve body 65 is closed by a plug 67 having an passage and press fitted, welded or otherwise fixed therein with a portion protruding from the end of body 65 and threaded as indicated at 68. Threaded end 68 is adapted to threadedly receive one terminal connector element of coupling fitting 69 the other terminal connector element of which threadedly receives the coupler of hose 58. The opposite end of valve body 65 is closed by an internally tapped plug 71 press fitted, welded or otherwise fixedly secured therein. Between plugs 67 and 71 valve body 65 is perforated as indicated at 72 to permit free ingress of air and egress of air and entrained fuel as will presently be pointed out.

A metering pin 73 having a needle point 74 at its free shank end for flow controlling cooperation with the axial passage of plug 67, a threaded shank portion 75 spaced axially from needle point 74 to threadedly cooperate with.

the internally tapped plug 71 in all operative positions of needle point 74 and a head 76 on the shank portion protruding from plug 71 and fixedly carrying lever arm 78. Lever arm 78 is engaged by one end of a coil spring 79 the other end of which is fixed in an axially directed opening in plug 71 so as to be tensioned upon counterclockwise movement of arm 78 to tension spring 79 to provide resilient force for reversing rotation of pin 73 to close off the fuel flow through plug 67. It Will be appreciated that rotation of metering pin 73 in opposite directions will translate meter pin 73 axially back and forth with respect to valve body 65 in a definitely predeterminable amount depending upon the lead of the screw threads 75 and the angular movement imp-auted to arm 73. It follows, therefore, that by determining (empirically or mathematically) the fuel flow permitted by metering pin 73 at its various stages of flow opening and knowing the engine fuel requirements between idling and maximum load operation and the angular throw of arm 78, the ideal fuel supply for all intermediate engine operating conditions as well as maximum load operating conditions can be predetermined by choice of a suitable lead for screw threads 75.

Assuming that an appropriate thread lead has been adopted and that metering pin 73 is in its fully closed position preventing fuel flow through the inlet passage of plug 67, the present invention contemplates effecting operation of lever arm 78 in direct response to a critical operating characteristic of the engine to assure a proper fuel-air ratio. While any suitable characteristic may be utilized, that most readily available and under direct control of the engine operator is the intake manifold air flow. The flow rate of intake manifold air, it will be appreciated, is directly related to the engine speed which is normally controlled by the operators actuation of throttle valve 42 to accelerate and decelerate the engine to move a load at varying speeds. While in present day conventional engine operation, actuation of throttle valve 42' is, through suitable carburetor linkage, utilized to simultaneously and in successive stages increase fuel flow as well as air flow the rate of fuel supply is determined by differential pressures along the path of the incoming air stream and the raw fuel is introduced directly into the air stream at the point of its greatest acceleration. Such a manner of fuel supply fails to assure a proper intermixing of fuel and air to assure maximum efiiciency of consumption of the supplied fuel or to directly relate the quantity of supplied fuel to the volume of inflowing air to avoid an over rich fuel mixture.

In the present invention, these objections are avoided by varying the arnount of fuel supplied in direct relation to the volume of incoming air and introducing the fuel into a turbulent portion of the incoming air stream in the form of a spray under pressure in a manner to assure entrainment of the fuel by the air, a merging of the portion of air and entrained fuel with the remainder of the incoming body of air at a downstream point of turbulence to effect a maximum admixture of fuel and air. To this end, body housing 62 downstream from fuel sleeve 61 is provided with a deflector vane 89 carried by a shaft 91 journalled adjacent its opposite ends in journal openings 92 provided in diametrically opposed bosses 93 formed on the wall of body housing 62 in axial parallelism to valve body 65. While deflector vane 89 may take any suitable form, it preferably comprises a perforated disc segment 94 (FIGURE 4) of semicircular configuration having its median edge disposed in an axial slot 95 formed in shaft 91 and secured to shaft 91 by headed screws 96 passing freely through suitable openings in the upper half of shaft 91 and the median edge of disc segment 94 and threaded into suitably aligned tapped open ings in the lower half of shaft 91. It will be appreciated that this structure permits vane 89 to be assembled with shaft 91 after the shaft itself is inserted endwise into its journal openings '92 to dispose slot 95 within passage 17.

The end of shaft 91 beneath the protruding portion of metering pin 73 protrudes from boss 93 and fixedly mounts a lever arm 97 which in turn is linked to lever arm 78 of metering pin 73 by a link rod 98. As will best appear from FIGURE 2, arms 7 3 and 97 extend upwardly and to the left at about 40 to the horizontal as represented by the dotted line showing of vane 89. It follows, therefore, that for every degree of counterclockwise movement of vane 89 and its shaft 91 a maximum vertical movement of drive arm 97 and follower arm 7 8 will take place to assure a comparable maximum angular move ment of metering pin 73. As a consequence, an appropriately chosen lead for threads 75 will be effective to secure any desired axial movement of metering pin 73 once the maximum angular movement of vane 89 and levers 97 and 78 is established.

Since vane 89 is deflected downwardly and counterclockwise as seen in FIGURE 2 by impact of the incoming air, when the volume of air exeeds that required for idling speed operation and which passes through and to the side of vane 3%, each angular degree of deflection of vane 89 will effect a corresponding counterclockwise movement of shaft 91 and arm 97. They in turn will, through link rod 93, effectively rotate arm 78 and metering pin '73 in a counterclockwise direction. This counterclockwise rotation of pin 73 threads pin 73 outwardly with respect to tapped plug 71 withdrawing needle point 74 axially to the left as seen in FIGURE 2 to first open and then progressively enlarge the opening between needle point 74 and the fuel admission passage of plug 67. So long as throttle valve remains in its newly opened position and the load conditions remain constant the inflow of air will remain constant, the new open position of vane 39 and metering pin 73 will be maintained and the fuel-air mixture necessary to maintain the new throttle selected engine speed will be automatically assured. If the load increases, the engine speed will decrease, the volume of air flowing past vane 89 will decrease, the tension in spring 79 acting constantly in opposition to opening movement of vane 89 will rotate metering pin 73 in a clockwise direction translating pin 73 axially to the right to restrict the flow of fuel and at the same time act through levers 78 and 97 to rotate vane 89 in a clockwise direction to the degree permitted by the air flow requirements of the engine thereby maintaining an optimum air-fuel mixture in accord with the falling engine speed. However, opening of throttle 42. under these conditions will, because of the pressure drop across throttle 42, produce a surge of air against vane 89 efiecting a rapid opening of the rneterin pin orifice to augment the acceleration pump and provide a momentary supply of a rich fuel mixture to speed up the engine and thereafter assure a metering pin orifice opening to establish a still higher speed fuel-air mixture to overcome the increased load. lt will be appreciated, therefore, that manipulation of throttle 42 in the conventional and familiar manner is all that is required to maintain the desired engine operation While assuring the automatic and economical maintenance of an optimum fuel-air mixture at all times.

Summarizing the operation of the carburetor of the present invention, and assuming that a cold engine is to be started, the operator by pressing the throttle pedal while the starter switch is closed actuates the accelerator pump to inject a charge of fuel into the small volume of inflowing air thus forming a rich starting mixture. Upon ignition of this starting charge, the engine speed will pick up considerably causing a surge of incoming air against vane 89 to momentarily open the metering orifice around needle point 74 permitting a further excess charge of fuel to enter the incoming air and build up the engine speed to normal idling speed determined by the then closed throttle valve 42. At this point, the surge of air having passed vane 89, vane 89 and metering pin 73 are returned by spring 79 to their normal closed idling speed positions. In event the cold engine dies out the starting procedure is repeated or, if the driver is alert to a speed fall off from idling speed, a slight pumping of the throttle lever may be effected to actuate the acceleration pump and assure a rich fuel-air mixture until smooth idling is automatically maintained. It will be appreciated that driving of the engine by the starter motor operates the fuel pump (not shown) so that fuel under pressure is always available in hose '7 and T-fitting 56. If float chamber 19 is not filled, the initial charge of fuel from the fuel pump will flow into the float chamber through filter chamber 32 and past open needle valve 223. This is assured since metering pin 73 will be closed preventing fluid flow through hose 58. Once float chamber 19 is filled, the rising float structure will close needle valve 28 and the further fuel discharged by the fuel pump will enter the by-pass connection of fitting 26 leading to hose 5%. When hose 58 has become filled, a momentary operation, the pumped fuel will be supplied in sufficient volume to alternately and continuously maintain float chamber 19 filled and hose 58 and the passages to metering pin 73 filled with fuel. When either or both of the needlevalves 28 and 73 are open the supplied fluid will be sprayed into the float chamber or valve body 61 under pump pressure.

Assuming the engine to be operating at idling speed and that throttle 42 is opened to increase engine speed, the first result will be that the acceleration pump will introduce an excess charge of fuel into the passage 17 and simultaneously an increased volume of air will move from passage 17 through passage 18 past throttle valve 42 under influence of the pressure drop across throttle valve 42 to effect a momentary acceleration of the engine speed. The surge of replacement air entering passage 17 augmented by the increased intake demands of the accelerated engine act on vane 89 almost instantly to initiate opening movement of metering pin '73 to establish a main fuel flow in the form of a spray into valve body 65. This sprayed fuel is intermixed and entrained by the air flowing through the apertured valve body 65 and forms a multiplicity of finely divided rich fuel-air mixture streams which are introduced into the main body of inflowing air immediately downstream from valve body 65. The main body of air and these fine rich fuel-air mixture streams upon reaching the area of vane 89 are admixed due to the turbulence caused by vane 89 and its shaft 91 and passes onward through passage 18 and past throttle 42 where a further admixing of the air and entrained fuel takes place to assure a more highly combustible air-fuel mixture. Both vane 89 and throttle valve 42 have a vaporizing action also since any fuel droplets that impinge on them spread out over the metal surfaces and are entrained or absorbed by the predominant air flow over and past these metal surfaces. As a consequence, the present invention assures an unusually eflicient and highly combustible air-fuel mixture and a carburetor structure having fewer parts and a lesser number of moving parts likely to get out of order thereby assuring a structure of greater effectiveness that is decidedly less costly to manufacture and maintain.

The invention may be embodied in other specific forms without departing from the spirit or essential characteris tics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come Within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a carburetor for an internal combustion engine comprising a main body housing defining an air and fuel mixture passage, a float chamber conventionally adapted to supply fuel to an idling speed fuel passage system from a source of fuel under pressure and intake manifold coupling means secured to one end of the main body housing and including an outlet passage forming a continuation of said air and fuel mixture passage and an operator controlled throttle valve in said outlet passage: a main fuel supply system comprising an air inlet housing mounted on the other end of said main body housing and having an inlet passage communicating with said air and fuel mixture passage; a fuel metering assembly comprising a perforated sleeve spanning said inlet passage and formed at one end with a fuel admission port; a fuel metering pin axially adjustably mounted in and extending from end to end of said perforated sleeve with one end entering said admission port and shaped to meter the flow of fuel emanating from said fuel admission port and its other end protruding from the other end of said perforated sleeve and through and beyond the outer wall of said air inlet housing; a T-coupling having one discharge branch communicating with the float chamber and the other discharge branch connected to the fuel admission port, said T-coupling inlet being adapted to be connected to a source of pressurized fuel whereby said float chamber and said fuel admission port are supplied with fuel at a positive pressure; a deflector vane in said inlet passage in the path of flow of air passing through said inlet passage, said deflector vane being fixedly mounted on a rotatable mounting shaft having one end protruding through and beyond the outer wall of said air inlet housing in spaced juxtaposition to said protruding end of said fuel metering pin; and linkage means operatively interconnecting the protruding ends of said fuel metering pin and said rotatable mounting shaft and biasing said deflector vane and its mounting shaft to its full obstructive position during idling speed operation of said engine, whereby, upon acceleration of said engine above idling speed, the volume of incoming air impinging on said deflector vane will deflect said vane and through said mounting shaft and linkage will shift said fuel metering pin to increase the supply of fuel passing through the fuel admission port to said perforated sleeve in accord with the deflected position assumed by said deflector vane in response to the intake manifold induced flow of air.

' 2. The carburetor of claim 1 wherein said linkage means includes spring means normally yieldingly biasing said deflector vane and its mounting shaft toward inlet passage obstructing position against the deflecting force of the incoming air whereby, when said throttle valve is at its idling speed position, said metering pin will be maintained in position to shut off the fuel supply through said main fuel supply system and maintain engine idling speed through the idling speed fuel passage system.

3. The carburetor of claim 1 wherein said perforated sleeve spans said inlet passage upstream from said deflector vane in the path of the full flow of entering air to assure passage of the full entering air flow through and around said perforated sleeve at all times and initial admixture of the metered fuel entering said perforated sleeve with the air passing through said perforated sleeve to form a multiplicity of air-fuel streams discharging into the main air stream at all times to assure an optimum fuel-air mixture.

4. An internal combustion engine carburetor comprising a main body housing defining an air and fuel mixture passage, a float chamber conventionally adapted to supply fuel to an idling speed fuel passage system and a fuel inlet connection adapted for connection to a fuel supply line supplied with combustible fluid under pressure; coupling means secured to the main body housing at the outlet end of the air and fuel mixture passage and including an operator controlled throttle valve, flange means for operatively connecting said coupling means to the inlet of the intake manifold of an internal combustion engine and a fuel and air outlet passage communicating at its opposite ends with the main body air and fuel mixture passage and the intake manifold chamber; an air inlet housing mounted on the other end of said main body housing and having an inlet passage communicating with said air and fuel mixture passage; a fuel metering assembly comprising a pefiorated sleeve spanning said inlet passage and formed at one end with a fuel admission port and a fuel metering pin axially, adjustably mounted in and extending from end to end of said perforated sleeve with one end entering said admission port and shaped to meter the flow of fuel emanating from said fuel admission port and its other end protruding from the other end of said perforated sleeve and through and beyond the outer wall of said air inlet housing; a T- coupling having one discharge branch communicating with the float chamber and the other discharge branch connected to the fuel admission port, said T-coupling inlet being adapted to be connected to a source of pressurized fuel whereby said float chamber and said fuel admission port are suppled with fuel at a positive pressure; a deflector vane in said inlet passage in the path of flow of air passing through said inlet passage, said deflector vane being fixedly mounted on a rotatable mounting shaft having one end protruding through and beyond the outer wall of said air inlet housing in spaced juxtaposition to said protruding end of said fuei metering pin; and linkage means operatively interconnecting the protruding ends of said fuel metering pin and said rotatable mounting shaft and biasing said deflector vane and its mounting shaft to its full obstructive position during idling speed operation of said engine, whereby upon acceleration of said engine above idling speed the volume of incoming air impinging on said deflector vane will deflect said vane and through said mounting shaft and linkage will shift said fuel metering pin to increase the supply of fuel passing through the fuel admission port to said perforated sleeve in accord with the deflected position assumed by said deflector vane in response to the intake manifold induced flow of air.

5. The carburetor of claim 4 wherein said linkage means includes spring means normally yieldingly biasing said deflector vane and its mounting shaft toward inlet passage obstructing position against the deflecting force of the incoming air whereby, when said throttle valve is at its idling speed position, said metering pin will be maintained in position to shut off the fuel supply through said main fuel supply system and maintain engine idling speed through the idling speed fuel passage system.

6. The carburetor of claim 4 wherein said perforated sleeve extends across said inlet passage upstream from said deflector vane in the path of the full flow of entering air to assure passage of the full entering air flow through and around said perforated sleeve at all times and initial admixture of the metered fuel entering said perforated sleeve with the air passing through said perforated sleeve to form a multiplicity of air-fuel streams discharging into the main air stream at all times to assure an optimum fuel-air mixture.

7. A high speed fuel supply mechanism for use with a fuel pump and a carburetor mechanism for supplying an idling mixture of air and fuel to the intake manifold of an internal combustion engine comprising means defining an air inlet housing adapted to be mounted on said carburetor mechanism and having an air inlet passage leading to the air-fuel passage of said carburetor mechanism; a main fuel supply means mounted in said air inlet housing comprising a perforated sleeve spanning the air inlet passage at its upstream end, passage defining coupling means at one end of said perforated sleeve including a fuel metering passage leading to the interior of said sleeve at said one end, tube means connecting said passage defining coupling means to supply said fuel metering passage with fuel from said fuel pump, a metering pin axially movably threadedly mounted in said perforated sleeve with one end tapered and disposed to enter said fuel metering passage; and control means comprising an air deflector vane mounted in said air inlet passage in position to be acted upon by the air passing therethrough, a

rotatable support shaft movably connected to said deflector vane, means interconnecting rotatable shaft and said metering pin and adapted to normally axially position said metering pin to close oif said metering passage so long as the throttle of said carburetor is in its idling throttled position and said deflector vane is in full passage obstructing position and to threadingly retract said metering pin and open said metering passage to permit respective predetermined quantities of fuel to flow through said metering passage and said perforated sleeve into the entering air in said inlet passage in accord with the deflected position of said deflector vane determined by the increased flow of entering air permitted by the various open throttle positions of said throttle valve to thereby assure an optimum air-fuel mixture at all engine speeds.

8. The mechanism of claim 7 wherein. said linkage means includes a biasing spring for retaining said deflector vane in its maximum air inlet passage obstructing position against the deflecting force of the entering air flowing at the idling speed position of said throttle valve.

9. The mechanism of claim 7 wherein said linkage mews includes a crank arm flxed to said metering pin, a lever arm fixed to the shaft of said shaft supported deflector vane and a link element having one end pivotally connected to said lever arm and its other end pivotally connected to said crank arm to effect an angular movement of said crank arm in direct relation to a respective angular deflection of said shaft supported deflector vane whereby the relative axial movement of said metering pin can be predetermined by selection of the thread lead of said metering pin mounting to assure an optimum airfuel ratio in accord with the intake manifold characteristics of the particular engine with which the carburetor is used.

10. The main fuel supply mechanism system of claim 1 wherein said fuel metering pin is threadedly mounted in said perforated sleeve and said linkage means comprises a crank arm fixed to said metering pin, a lever arm fixed to the shaft of said shaft supported deflector vane and a link element having one end pivotally connected to said lever arm and its other end pivotally connected to said crank arm to effect an angular movement of said crank arm in direct relation to a respective angular deflection of said shaft supported deflector vane whereby the relative axial movement of said metering pin can be predetermined by selection of the thread lead of said metering pin mounting to assure an optimum airfuel ratio in accord with the intake manifold characteristics of the particular engine with which the carburetor is used.

11. The carburetor of claim 4 wherein said fuel metering pin is threadedly mounted in said perforated sleeve and said linkage means comprises a crank arm fixed to said metering pin, a lever arm fixed to the shaft of said shaft supported deflector vane and a link element having one end pivotally connected to said lever arm and its other end pivotally connected to said crank arm to effect an angular movement of said crank arm in direct relation to a respective angular deflection of said shaft supported deflector vane whereby the relative axial movement of said metering pin can be predetermined by selection of the thread lead of said metering pin mounting to assure an optimum air-fuel ratio in accord with the intake manifold characteristics of the particular engine with which the carburetor is used.

12. An intern-a1 combustion engine carburetor comprising a main body housing defining an air and fuel mixture passage, a float chamber conventionally adapted to supply fuel to an idling speed fuel passage system and a fuel inlet connection adapted for connection to a fuel supply line supplied with combustible fluid under pressure; coupling means secured to the main body housing at the outlet end of the air and fuel mixture passage and including an operator controlled throttle valve, said coupling means being adapted for connection to the intake manifold of an internal combustion engine and having 1 1 a fuel-air outlet passage communicating at its opposite ends with the main body air and fuel mixture passage and the intake manifold chamber; and a main fuel supply system comprising an air inlet housing mounted on the main body housing and having an inlet passage communicating with the main body air and fuel mixture passage opposite said outlet passage of said coupling means, fuel metering means spanning the inlet passage of said air inlet housing, means to supply pressurized fuel to said float chamher and to said fuel metering means, deflector vane means mounted in said inlet passage in the path of flow of air entering said inlet passage and norm-ally biased to a maximum passage obstruction position against an idling speed inflow of air and means interconnecting said deflector vane means and said fuel metering means to retain said 15 2,445,098

References Cited in the file of this patent UNITED STATES PATENTS 1,823,019 Wolford Sept. 15, 1931 1,900,191 Mock Mar. 7, 1933 2,084,489 Hess June 22, 1937 Wirth June 13, 1948

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