US2653804A

US2653804A - Fuel metering control for injection carburetors

Info

Publication number: US2653804A
Application number: US283403A
Authority: US
Inventors: Oscar R Cedarholm
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-04-21
Filing date: 1952-04-21
Publication date: 1953-09-29
Anticipated expiration: 1970-09-29

Description

Se t. 29, 1953 o. R. CEDARHOLM 2,653,804

FUEL METERING CONTROL FOR INJECTION CARBURETORS Filed April 21, 1952 2 Sheets-Sheet 1 Fig].

Oscar R. Gedarho/m IN VEN TOR.

Patented Sept. 29, 1953 UNITED STATES PATENT OFFICE FUEL METERING CONTROL FOR INJECTION QARBURETORS Oscar- R. Gedanholm, Quincy; Mich Application April 21, 1952, Scrial No'. 283, 403

(Cl; Z6151');-

11 Claims. 1

This invention comprises novel and useful improvements in an automatic control for'injection carburetors and relates to similar subject: matter and constitutes an improvement over my prior copending application Serial No. 174,927, filed July 20, 1950, for Injection Carburetor, now Patent No. 2,636,488; issuedApril' 28, 1953;

This primary object of this invention is'tow provide an improvement in the type of carburetor disclosed in my above identified patent and other carburetors operating upon analogous principlesof operation, by providing an attachment capable" of providing a limit, either upper or lower, depending upon the desire of the user of the at;- tachment, which will govern the richness of fuelair mixtures which pass through the riser into each cylinder; usually by way of an intake manifold.

A further object of this invention is, to provide an injection type carburetor having a greatly simplified construction inasmuch as the customary float; float valve, float chamber, venturi and other analogous structures have been omitted entirely;

A further object of the invention is to provide. an improved carburetor: in which the fuel-air ratio shall be automatically varied in response to changes in the man-ifoldipressure and in response to the throttle valve opening, togetherwith means operable to varythe fuelrairratio for choking the carburetor for starting.

A further important object" of the invention is to provide a carburetor construction in accordance with the foregoing objects and in which a more efiective mixing of the components of the fuel charge shall be obtained.

These, together with various ancillary features and, objects of the invention, which will later become apparent as the following description proceeds, are attained by the present invention, a preferred embodiment of which has been illustrated; by way of example only, in the accompanying drawings, wherein:

Figure 1 is a side elevational' view showing a carburetor constructed in accordance with the principles of this invention Figure 2- is a vertical sectional longitudinal view through the carburetor of Figure l, the parts of the mechanism being shown in their position when the throttle valve is closed and the engine is not running;

Figure 3' is a fragmentary View similar to Figure 2 but showing the position of the parts during. operation of, the, engine;

Figure 4 is a fragmentary detail'vi'ewtaken in 2 section upon the plane indicated by the section line- 4-4 of Figure 2; and showing in particular the manner in which the throttle valve is connected to the meteringfuel valve for effecting operation of the same Figure 5 is afragmentarydetailv sectional view taken upon anenlarged scale substantially upon the plane indicated by the section line 5--5 of Figure 2 and illustrating the mechanism for opcrating the fuel valve metering assembly during the choking operation ofthedevice; and,

Figure 6 i's-afragmentary sectional viewtaken upon an enlarged scale and showing the valve core and valve body of the fuel metering valve, in accordance with this invention.

Reference is now" made more specifically to the accompanying drawings, wherein like numerals designate similar parts throughout the. various views. The improved carburetor incorporating the principles of this invention consists of a riser HII whose upper endis provided with a shoulder I2 and a cylindricalupstanding sleeve extension [4 which are adapted" to receive'the conventional air cleaner with which automobile engines are customarilyequippedi The lower end of the riser is provided with an annular flange Hi by means of which the riser is: adapted tobe secured tothe intake manifold of an" internal combustion engine for, supplying acarbureted mixture thereto.

If desired, the carburetor maybe'water jacketed as by providing a jacket It thereabout' whereby the carburetor may be preheated in accordance with stand'ardpracti'ce.

A conventional formof butterfly throttle valve 20' is, mounted in an, appropriate portion of the riser i0, being pivotally secured therein as by a transverse throttle valve pivot pin 22- extending through the opposite walls of the riser, this pin having one extending end provided with a throttle valve lever: M, see Figure l, which at one end is provided with a flangedporti'on 26 through which extends a throttle valve actuating member 23 which may? conveniently comprise a flexible cable or the like having a collar 30- secured thereto adjustably" as by a set screw 32 and manually onerablefrom the vehicle dash. Obviously by oncrating: the cable 28 in the direction indicated by the arrow 3d, the" throttle valve will be moved to its open position as'will .be apparent bycomparing'Figures 2 and 3.

The conventional foot or accelerator-pedal control of, the throttle valve 20 is accomplished through a lever 31 and link' 33-, shown in dot and dash lines in Figure. l and fixedly connected to the shaft 22'. It will be evident that operation 3 of the throttle valve by the lever and link 3| and 33 will not affect 28, since the lever 24 will slide upon the cable 28.

The other end of the throttle valve lever 24 is provided with an adjusting screw 36 having a lock nut 38 thereon, for a purpose to be hereinafter specified.

Intermediate its ends, the riser I is provided with an integral upwardly inclined projection 40 which at its upper and outer end is provided with a cylindrical bore 42 comprising a chamber, that portion of the body 40 which surrounds the chamber 42 comprising a casing for the same and being provided with a closure member 44, as shown in Figure 1, of any desired character.

A bore 46 extends axially from the bottom wall of the chamber 42 in the projection 40 and inter" sects the passage in the riser ID at a position which is below or downstream of the throttle valve 20. This passage is adapted to receive a fuel injecting metering valve of the same general character and construction as that set forth and claimed in my above identified patent, and the axis of this bore is inclined so as to be directed towards the opposite side of the riser, and in fact being preferably so positioned as to impinge upon the intersection of the opposite wall of the riser and a horizontally extending bafiie 48 which is mounted upon the opposite wall of the riser, extends across the entire width of the air passage through the riser and into a recess 58 in the wall of the riser which recess thus provides a passage around the end of the horizontally disposed baifle. A suction conduit 52 extends from the interior of the recess 50 above the baffle 48 into the chamber 42 through the bottom wall thereof.

A by-pass passage 54 is provided in the riser having an inlet end 56 disposed above the throttle valve 28 when the latter is at its closed or substantially closed position, and having its exit or discharge end 58 in the form of a port entering the passage through the riser immediately above and adjacent to the connection of the horizontal baffle 48 with the wall of the riser. A manually operated adjusting screw 68 is provided having a conical metering tip 62 engaging in the orifice 58 for regulating and controlling the rate of flow through the by-pass passage, to thus facilitate and permit idling of the engine when the throttle valve is closed.

As so far described, it will now be apparent that air passing into the riser I0 will be discharged upon the baffle plate 48 by the by-passage 54 when the throttle valve is closed, and will be discharged by both the by-passage 54 and by the main flow coming past the throttle valve when the latter is opened, this air supply then flowing across the baffle 48 transversely thereof and in the recess 58 and thereafter passing downwardly through the riser and into the intake manifold. The metered fuel charge, controlled by the metering control valve assembly to be hereinafter described, is injected into this air flow at the port 58, whereby the air streams will intermingle with and mix with the fuel supply and will be thoroughly intermixed therewith before passing around the end of the baffle and into the riser for delivery to the intake manifold. Thus, a very eflicient mixing of the air and fuel is provided, both for engine idling operation and for normal running conditions of the engine.

A valve body 64 in the form of a sleeve is movably and slidably received in the bore 45, and extends through the chamber 42 and through the cover 44. This valve body is provided with a cylindrical hollow interior 66 extending axially therethrough, the upper end of which is internally threaded to receive a sleeve coupling member 68 by which a flexible fuel supply conduit 18 is attached to the valve body. Fuel from any suitable source and in any desired manner is applied to the flexible conduit '15 and under the control of the metering valve as set forth hereinafter is discharged into the interior of the riser to form the fuel constituent of the combustible charge. The valve body 64 has its exterior surface of two different diameters, to thus provide an annular shoulder 12 which forms a seat for a disk or plate 14 which constitutes a partition member which is slidably received within the chamber 42. The member 14 has a fluid tight engagement with the walls of the chamber, this engagement being effected in any desired manner, whereby suction supplied from the recess 50 of the riser I9 is communicated by the passage 52 into the chamber 42 below the partition for yieldingly urging the partition member towards the bottom of the bore of the chamber 42 during operation of the engine.

It will of course be understood that atmospheric pressure is admitted to the chamber 42 upon the upper or other side of the partition member '14 in any desired manner to permit the suction of the intake manifold to be thus effected. The partition member 1'4 is of course fixedly secured to the valve body 64 whereby movement of the partition member will in turn cause movement of the valve body relative to the projection 49.

The lower end of the valve body is likewise internally threaded to receive a plug 15, see also Figure 6. This plug is hollow being provided with apertured walls 18 and at its opposite ends, which walls serve as guides for slidingly supporting a valve core 82, whose upper end extends into the valve body '64 and is slidable axially of the chamber 66 therein. As shown in Figure 6, the upper end of the valve core 82 is provided With a valve ring or sealing member 84 seated in an annular groove in the valve core which is adapted to abut against the wall 18 to prevent further downward movement of the valve core within the plug 16 and to seal off the fuel supply, and is further provided with an axial upward extension 86 which serves to position the lower end of a compression spring 88 whose upper end bears against the spring seat 98 which is constituted by an internal rib at the upper end of the passage 66.

The valve ring 84 possesses the very important function of seating on the wall 78, which thus is a valve seat, when the engine stops, to thus protect leakage of fuel from the fuel supply line, which is still under pressure from the fuel pump for some time after the engine stops, and would leak past the valve core and wall 18 and flood the engine.

It will thus be apparent that the spring 88 yieldingly urges the valve core downwardly with respect to the bore 46, and the valve body 64 upwardly with respect thereto, thus urging both of the valve members in opposite directions with respect to the riser and bore 46, and with respect to each other.

The valve core is provided with a longitudinally extending fuel supply passage or channel 92 of a progressively increasing depth from its shallow upper end to its lower end as will be apparent from Figure 6. The arrangement is such that when the valve core is at its lowermost position with respect to the valve body as shown inFigure 6, with the valve ring 84' abutting against the wall '38 of the plug 76, the liquid fuel supplied. to the passage 66 by the conduit I0 is cut off from passage through the channel 92'. However, when the valve core is displaced upwardly into the valve body, liquid fuel passes into the channel 92 through a port of varying cross section area depending upon the extent of movement of the channel 92 into the chamber 66.

As will now be apparent by comparing Figures 2, 3 and 6, the liquid passing through the valve core is discharged from the lower end of the channel 92 into the air stream at the junction of the by-pass withthe baffle 48. This liquid fuel is then mixed with the incoming air either moving through the by-pass and/or moving through the riser past the throttle valve and during the passage of the air and fuel across the baffle 48 into the recess 50 will be throughly. intermixed with the same.

As will now be further apparent, the position of the valve body '64 in the bore 46 is controlled by the suction of the intake manifold applied to the underside of the partition 14 through the passage members 53 and 52. The position of the valve core is independently adjusted with respect to the adjustment of the valve body by connecting the valve core to the throttle valve 20 for simultaneous action therewith. For this purpose, as will. be apparent from Figures 2, 4 and 6, the undersurface of the throttle valve 20 is provided with a pair of parallel arm 94 in the form of plates which engage and are attached to opposed parallel flat surfaces 93 recessed in the sides of a collar 83 which is fixedly attached in any desired manner upon the valve core 82. It will thus be apparent that upon pivotal movement of the throttle valve, the engagement of the arms 94" carried thereby with the collar 98 will cause a corresponding upward movement of the valve core 82. It will thus be understood that since relative movement of the valve core and valve body will vary the metering of the liquid fuel supplied through the valve assembly into the carburetor, variation of this fuel supply can be controlled by absolute movement of either the valve body through the suction operated partition member 714, the valve core 82 through the operation of the throttle it, or both.

It should be noted that with the engine stopped and the valve assembly in the position shown in Figure 6, and with the valve ring 84 seated on the member 15, the fuel is sealed off from the carburetor and the entire valve assembly, consisting of the

members

82, 98, i5, 88, 64, 84, is actually floating freely as a unit in the bores 42 and it. For example, with the engine at rest, if the throttle valve 23 were opened, the arms 94 would merely cause the above mentioned valve assembly to float ahead or slide in the bores 42 proximity to the air stream from the orifice 582 of the Icy-pass or the air passing the throttle valve.

The above described metering valve construction, except as to the manner of connecting the valve core to. the throttle valve for simultaneous operation therewith, is substantially identical with that set forth in my above identified patent.

However, in the present applicationv and in the presentconstruction, a novelform of stop. means is provided for limiting the downward travel of the partition I4 in the chamber 42 and a downward movement of the valve body 64 in the bore 46. This stop means consists of a plunger I102. which is slidabl'e in a bore I04 in the projection 48, this plunger engaging the underside of and abutting the underside of the partition member I4. At its lower end, the bore I04 intersects the transverse bore I06, see also Figure 5, which extends through the projection 40 of the riser I 0. Rotatably seated within the bore 106 is an actuating shaft I03 which adjacent one end is provided with an annular groove III) which is err--- gaged by a retaining screw II2 which thus permits rotational but prevents axial movement of the actuating shaft. actuating shaft is provided with an annular groove II 4 whose bottom surface constitutes an eccentric member IIB- which is engaged by the lower end of the plunger I 02. It will thus be ap parent that upon rotation of the actuating shaft I68, the plunger will be reciprocated in its bore and thus will constitute an adjustable abutment for limiting the downwardtravel of the partition member and consequently of the valve body;

With the engine at rest, as shown in Figure 2, it is assumed that the engine is cranked for starting; A suction is then developed below the throttle valve 20 which is communicated by passage 52 to the partition I4. Now, if any gap exists between the bottom side of 14 and the end ofthe plunger I82, before starting the engine, it will be closed when the suction brings the partition I4 down into contact with I02; However, as mentioned earlier herein, the valve core 82' with itscollar 98 was already resting upon the arms 94 and therefore cannot move. It will nowbe clear that

parts

16, 64, I4 will move down to plunger I02, closing the gap, which movement will open the seal at 84-and-18 and permit flow of fuel. The movement will be equal'to the gap between "I4 and H12; It should be noted that during the above procedure, thethrottle valve and its arms 94 were not moved from their closed positions of Figure 2.

Referring now again to Figurel it will be seen that the end of the actuatingshaft I08 has an actuating lever II 8 secured thereto, this lever having at one extremity a cam surface I20 which rides against and is engaged by the end of the adjusting screw 36 previously mentioned. C011? sequently, as the actuating shaft is rotated, the cam surface I20 through the adjusting screw 36 causes rotation of the lever 24 and of the throttle valve shaft 22, thereby opening the throttle valve as the actuating shaft is rotated in adirection to lower the plunger I02 and permit further movement of the partition member I4 towards the bottom of the chamber 42, and thereby cause downward movement of the valve body 64 within the bore 46.

Asbest seen in Figure 5, the other end of the lever H8. is provided with a pivoted connection I21v having a set screw I241 whichv is adapted to adjustably clamp upon the end of a. chokerod or choke wire I26. The latter extends to any con-- venient place as the dash of a vehicle whereby the same may be readily actuated by the driver of the vehicle.

Thisarrangement is such that whenit is desired Intermediate its ends, the

to start the internal combustion engine the driver will pull the choke rod I25 in the direction indicated by the arrow I28, thereby simultaneously opening the throttle valve to increase the flow of air passing the throttle, simultaneously lifting the valve core to open the fuel passage 92; and will also rotate the actuating shaft I08 in a direction to permit the valve plunger I02 to move inwardly thus adjusting the stop member to permit the partition member 14 to move downwardly under the influence of suction arising from the crank operation, thereby effecting a downward move ment of the valve body within the bore 46 further increasing the flow of fuel through the metering device.

It will be noted that the operation of the throttle to its further open position is independent of the choking device.

This valve assembly is especially effective in preventing the undesirable conditions known as vapor lock which renders engines hard to start. If any liquid fuel passes the valve ring 84 and seat I8 and enters the interior of the plug 18 by way of the passag 92, and vaporizes, the vapor is dissipated readily through the openings in the walls 80 of the plug and into the riser. ihus, the development of a vapor pressure in the valve assembly, which might imped the next desired fuel flow is completely prevented.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art after a consideration of the foregoing specification and accompanying drawings, it is not desired to limit the invention to the exact construction shown and described, but all suit able modifications and equivalents may be resorted to, falling within the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on the downstream side of said throttle valve connected to the valve core for displacing the same in said valve body upon movement of said throttle valve, means carried by said riser for adjustably limiting the range of movement of said partition.

2. In an internal combustion engine, an intak manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intak manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on the downstream side of said throttle valve connected to the Valv core for displacing the same in said valve body upon move ment of said throttle valve, manually operable plunger carried by said riser and engaging said partition for adjustably limiting the range of movement of the partition.

3. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intak manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on said throttle valve connected to the valve core for displacing the same in said valve body upon movement of said throttle valve, means carried by said riser for adjustably limiting the range of movement of said partition, said last means including a plunger engaging said partition and an eccentric engaging said plunger.

4. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means for actuating said valve core in said valve body upon movement of said throttle Valve, a stop in said riser limiting movement of said partition, said riser having a pair of intersecting bores, a plunger in one bore constituting said stop and having one end abutting said partition, an adjusting shaft in the other bore having an eccentric engaging the other end of said plunger, means for rotating said shaft.

5. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intak manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake inanifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on the downstream side of said throttle valve connected to the valve core for displacing the same in said valve body upon movement of said throttle valve, means connected to said last means and to said throttle valve for operating the latter upon movement of the former.

6. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on the downstream side of said throttle valve connected to the valve core for displacing the same in said valve body upon movement of said throttle valve, said last means comprising a pair of parallel arms, a collar mounted on said valve core, said collar having parallel 9 flat sides to which said arms are connected for moving said core.

7. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means on the downstream side of said throttle valve connected to th valve core for displacing the same in said valve body upon movement of said throttle valve, said last means comprising a pair of parallel arms, a collar mounted on said valve core, said collar having parallel flat sides to which said arms are connected for moving said core, said core and collar being slotted to form a fuel discharge channel into said riser.

8. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movabl mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intak manifold and casing for actuation of said partition in respons to pressure variations in said intake manifold, a valve core movable in said valve body, means for actuating said Valve core in said valve body upon movement of said throttle valve, said riser having a baffle extending from one wall of the riser and positioned downstream of said throttle valve and said valve core, a by-pass around said throttle valve discharging upon the upstream side of said bafiie, said valve body discharging fuel upon said baffie adjacent the bypass inlet thereto.

9. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means for actuating said valve core in said valve body upon movement of said throttle valve, said riser having a bafiie extending from one wall of the riser and positioned downstream of said throttle valve and said valve core, a bypass around said throttle valve discharging upon the upstream side of said baflie, said valve body discharging fuel upon said bafiie adjacent the by-pass inlet thereto, said riser having a recess extending around the other end of said baffle, whereby fuel and air impinging upon the baffle from the valve body and the by-pass and air passing the throttle valve will be mixed prior to the passage around the baffle through the recess.

10. In an internal combustion ngine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a source of fuel, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means for actuating said valve core in said valve body upon movement of said throttle valve, said riser having a baffle extending from one wall of the riser and positioned downstream of said throttle valve and said valve core, a by-pass around said throttle valve discharging upon the upstream side of said baiiie, said valve body discharging fuel upon said bafiie adjacent the bypass inlet thereto, said riser having a recess extending around the other end of said baffle, whereby fuel and air impinging upon "the baffle from the valve body and the by-pass and air passing the throttle valve will be mixed prior to the passage around the baffle through the recess, said passage means opening into said recess.

11. In an internal combustion engine, an intake manifold, a carburetor including an air intake riser communicating with said intake manifold, a throttle valve in said riser, a valve body movably mounted in said riser and adapted to be connected to a fuel source, a casing, a movable partition in said casing connected to said valve body, passage means connecting said intake manifold and casing for actuation of said partition in response to pressure variations in said intake manifold, a valve core movable in said valve body, means for actuating said valve core in said valve body upon movement of said throttle valve, said riser having a bafiie extending from one wall of the riser and positioned downstream of said throttle valve and said valve core, said valve body discharging fuel upon said bafiie.

OSCAR R. CEDARHOIM.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,279,100 Gilles Sept. 1'7, 1918 1,730,268 Constantinesco Oct. 1, 1929 2,610,044 Wirth et a1 Sept. 10, 1952