US1375684A - Carbureter - Google Patents

Description

W. A. EDWARDS.

CARBURETER.

RENEWED FEB. 3, 1921.

APPLICATlON FILED NOV. 15.1915.

Patented Apr. 26, 19210 Tire? Application filed November 15, 1915, Serial No. 61,505. Renewed February 3, 1921.

UNITED STATES PATENT OFF-ICE.

TO WILLIAM REID, OF CHICAGO, ILLINOIS.

cazemian'rna.

To all whom it may concern:

Be it known that I, WVILLIA A. EDWARDS,

a citizen of the United States, residin at is controlled directly from the auxiliary air supply valve, so that the needle valve is opened proportionately to the openingof the auxiliary air valve. It has beenfound, however, that in certain'types of engines,

particularly those employing eight or more cylinders, it is essential that a very rich mixture be supplied during the starting or acceleration period of the engine. To meet this condition my present invention is designed primarily to furnish to the vaporlzing chamber an unusual amount of gasolene during the period of acceleration of the engine, and to subsequently supply gasolene in direct proportion to the amount of air takenin so that a mixture of uniform and predetermined richness will be maintamed.

. Another object of my invention is to provide mechanism which will perform the functions and fulfil the re uirements above mentioned entirely automatically, so that no manual adjustments of the carbureter need be made by the driver when the engine is to be started, thereby obviating any possibility of delivering to the cylinders an improper or inefficient mixture. Furthermore, by making the operation of the carbureter and the proportioning of the liquid fuelto the air entirely automatic the highest engine efliciency under all conditions of use is secured.

Inorder to facilitate an understanding of my invention I have illustrated on the accompanying drawings one preferred embodiment thereof from an inspection of which, when considered in connection with the following description, the principles of the invention and many of its inherent and Specification of Letters Patent.

Patented Apr. 26, 1921.

Serial No. 442,543.

attendant advantages will be readily appreciated. Referring to the drawings- F1gure 1 is -a central vertical sectional V ew of a carbureter embodying my inventlon, the float chamber appearing in side elevation;

Fig. 2 is a sectional view taken on the line 22 of Fig. l; and Fig. 3 is a fragmentary sectional view showlng certain of the parts in the position which they will assume when the engine is being started.

Referring to the drawings, the casingz'of the carbureter is of skeleton construction ASSIGNMENTS,

comprising a vertical tube 5', the upper portion of which forms the mixing'or vaporizing chamber 6 and is provided with a flange 7 for connection to the intake or manifold of v the engine, an auxiliary supply chamber or passage 8 communicating laterally with the mixing chamber, a constant air supply conduit 9 communicating with the lower end ,of the tube 5, a dash pot cylinder 10 below the juncture of the tubes 5 and 9, a piston rod housing 11 extending from the dash pot cylinder obliquely across the air supply pipe 9 and into the auxiliary air chamber 8, and the well or housing 12 forming a continuation of the dash pot cylinder 10 in which the fuel valve is mounted, as will be later described. A float chamber 13 of any well known or preferred construction is positioned at one side of the housing 12, the bottom of the chamber being in communication with thecentral chamber 15 of the housing 12 and with the dash pot cylinder 10 through a conduit or duct 14, preferably of Venturi shape. The float chamber is also in communication with, the upper end of the dash pot chamber through one or more ducts or tubes 16, which permits a free flow of liquid back and forth between the float chamber and the dash pot cylinder as the dash pot piston reciprocates therein, as will be later described.

A Venturi tube 17 is mounted in the lower end of the tube 5 and a nozzle piece 18 of .the fuel or needle valve projects upwardly air supply chamber 8 iscontrolled by an air tatably connected at its lower end with a guide or controlling member 21 by means of a pin and slot connection comprising a pin 22 extending transversely of the member 21 and oppositely disposed slots 23 formed in the member 20 and into which the pin'22 projects. The member 21 extends through the lower wall of the housing 12 and has a bearing against the outer end of a tubular member 24 which is equipped with a suitable packing gland 25 to prevent leakage around the member. The projecting end of the member 21 is equipped with a cross pin 26 or some suitable finger hold by which it may be turned for purposes of adjustment. A coiled expansion spring 27 interposed between the upper end of the member 21 and the upper end of the bore in the stem 20 urges the needle or metering pin toward its seat, the closing movement of the metering pin being limited by an annular collar 28 threaded upon the stem 20 and adapted to abut against the lower end of the nozzle piece 18, as shown in Fig. 1. It will be obvious that the normal position of the metering pin can be regulated to a fine degree of nicety by turning the member 21, which turns the metering pin within the collar 28, which is held against rotation with the stem 20 by a pivoted lever 29, the structure and purpose of which will be later described. The upper end of the mixing chamber 6 is equipped with the usual throttle valve 31 and the air intake pipe 9 is equipped with the usual butterfly valve 32. The auxiliary intake valve 33 of relatively large area normally seated against a valve seat or ring 34 by a coiled expansion spring 35 interposed between the lower end of the valve hub or stem 36, which is threaded upon the upper end of a piston rod 37, and the bottom of a sleeve 38 disposed Within the piston rod housing 11 around the stem or hub 36. The

tension of the spring 35 may be regulated by adjusting the sleeve 38 longitudinally in its housing, this result being accomplished by vmeans of a lever 39 attached at one end to the piston stem by an internalnut 44. The

piston 43 fits snugly but slidably within the piston chamber 10, and it will be manifest that when the auxiliary air valve 33 is opened against the force of the spring 35 by an inflow of air through the chamber 8 the piston 43 will be forced downwardly in the made between the piston 43 and the needle valve so that as the piston wasforced downwardly the needle valve would be correspondingly moved away from its seat to increase the supply of liquid fuel to the vaporizing chamber. In the present instance I have provided a construction by which the initial downward movement of the piston 43 is multiplied and transmitted to the needle valve with the result that the needle valve is withdrawn from its seat a distance greater than the, movement of the piston to thereby supply an initial charge of fuel of relatively largevolume. After this initial charge has been delivered and the engine has passed its period of accelera-' tion or, in other words, has picked up, the

needle valve is permitted to move back a limited distance toward its seat and is then maintained under the direct control of the piston 43 to be moved toward and from its seat proportionately to the movements of the piston and in accordance with variations in the speed of the engine.

With this end in view the piston 43 is equipped with a downwardly projecting annular flange 45'forming an annular chamber within the body of the piston itself in which a supplemental piston 46, snugly but slidingly fitting the inner faces of the flange 45, is positioned. This supplemental piston is provided with a stem 47 projecting upwardly into the stem 37 of the main piston, and an expansion spring 48 interposed be tween the bottom of a bore 49 in the enlarged portion 42 of the main piston stem, and a shoulder formed on the stem 47 normally urges the piston 46 into its lowermost position, as shown in Fig. 1. Downward movement of the piston 46 is limited by a flange 51 formed on a pivot pin 52 which is threaded into the piston 43 just outside 'the flange 45. The lever 29, which has been previously mentioned, is pivoted intermediate its ends upon the-pin 52 between two transversely extending pins 53 and 54 respectively, the lever being provided with an elongated aperture 55 through which-the pin 52 projects and which permits limited I longitudinal movement of the lever 29 upon its fulcrum sufficient to prevent binding of the lever in operation. One end of the lever 29 is connected to a stud 56 projecting downwardly from the piston 46 by means of a transverse pin 57, and the other end is bifurcated as shown in Fig. 2 to embrace the collar 28 which is threaded upon the stem 20. It will be observed that the collar 28 is provided with a circumferential groove in which the bifurcated ends of the lever 29 are Y disposed, and that this groove is divided by 'valve which renders the carbureter tremely sensitlve and responsive; in operaone or more vertically disposed webs 58, one of which engages in a similarly shaped notch 59 formed in the lever 29 and by which the collar 28 is prevented from rotating when the stem 20 of the needle valve is turned for purposes of adjustment. To prevent the' formation of a vacuum behind the piston 46 aport 61 is provided in the main piston 43 through which communication is established between the'supplemental chamber and the chamber above the main piston.-

It should be noted that the circumferential groove in the collar 28 is a little wider than the thickness of the lever 29 so that a limited amount of lost motion is provided in the connection between the auxiliary air valve and the needle of the fuel valve, which during normal running of the engine affords a delayed action of the air valve on the fuel ex? tion.

The operation of my invention is substantially as follows: Assuming that the engine to which the carbureter is attached is standing idle, the piston chamber and the central chamber 15 and a portion of the nozzle member 18 will be filled with gasolene. The engine is now turned over or started, by hand or by power, as the case may be, and the suction of the cylinders will cause the auxiliary air valve 33 to move inwardly away from its seat in the usual manner. The initial downward movement of the piston 43 by the-auxiliary ail valve 33 will, of course, positively force a quantity of fuel upwardly through the needle valve. vacuum above the piston 43 is prevented by the ducts or tubes 16 connected directly with the float chamber which permit gasolene to flow from the float chamber into the space abo the piston as the piston moves downwardly. If the needle valve were connected directly with the piston 43 the needle would be moved downwardly proportionately to the downward movement of the piston. As

previously stated, however, it is essential to.

engines of eight or more cylinders that an unusually rich'mixture be-delivered during the period of acceleration. This result is accomplished in my present invention by the supplemental piston 46 which as thepiston 43 moves downwardly against the pressure of the fluid in the chamber 10, will be moved upwardly relatively to the piston 43 against the force of the spring 48. As the pivot pin 52 travels downwardly with the piston 43 and as the piston 46 moves upwardly rela.--

tively to this pin it will be manifest that the lever 29 will be rocked about itsful'crum into the position shown in Fig. 3,"'thereby withdrawing the metering pin 19 from its seat a suitable distance to permit an unusually large flow of fuel through the needle valve The formation of any of the fuel in the piston chamber 10 below the pistons has been reduced by the dischargeofthe liquid through the needle valve the piston 46 will be returned to its normal position by the spring. 48, which return movement willJpartially close the needle valve and correspondingly restrict the flow of fuel. This unusually large although temporary flow of fuel permitted by the construction just described is sufficient to take care of the period of acceleration of the engine, and thereafter the flow of fuel should be proportionate to the flow of air through the carbureter which is, of course, controlled by the speed of the engine. After the piston 46 has resumed itsnormal position relatively to the piston 43 so long as the engine continues to run and relieve the pressure inthe pistonychamber below the pistons the main and supplemental pistons 43 and 46 respectively, will move back and forth under the control of the air valve 33 asa unit, and the needle valve will be opened and closed in proportionv to the opening and closing of the air valve. The width of the groove around the collar 28 will, however, permit aslightly delayed action of the needle valve which is conducive to the high est engine efficiency. When the engine is stopped the fuel pressure'in the piston cham her will again be restored and the operation of the carbureter when the engine is next started willbe'similar to that just described. It will be obvious that the formation of a partial vacuum above the supplemental piston 46 which would interfere with the sensitiveness of the device-is obviated by the port 61 which permits a free ingress and egress of liquid as the piston reci-procates in its chamber.

It is believed that the principles of my invention, its mode of operation and structural details of one embodiment thereof will be fully undertsood from the foregoing without further description, but it should tween said valves whereby said fuel valve is controlled by movements of'the air valve,

said connections including means for producing a maximum movement of said fuel valve'relatively to the air valve upon initial opening of' said air valve and thereafter a like movement of the fuel valve and the air valve. I

2. In a carbureter, the combination of a fuel valve, an air valve, and operative con-- nections between said valves including a fulcrum movable with said air valve and a lever attached at one end to said fuel valve and yieldably connected at its other end to said air valve whereby said fuel valve is controlled by the air valve.

3. In a carbureter, the combination of a fuel valve, an air valve, a piston connected to said air valve, a: fulcrum pin carried by said piston, a lever fulcrumed on said pin and connected at one end to said fuel valve, and a supplemental piston attached to the other end of said lever, y

4. In a carburetor, the combination of a fuel Valve, an air valve, a main piston connected to said. air valve, a supplemental pis ton carried by said main piston and movable relatively thereto, a fulcrum fixedly attached to said main piston, and a lever pivoted on said fulcrum and connected. atone end to said fuel valve and at its other end to said supplemental piston.

5. In a carbureter, the combination of a fuel valve including a metering pin, a spring for yieldably urging said pin toward its seat and a collar adjustably mounted on said pin, an auxiliary air valve, a dash pot piston connected therewith, a supplemental piston carried by said dash pot piston, and a lever carried by said dash pot pistonand connected to said supplemental piston and to said collar.

6. In a carburetor, the combination of a fuel valve, an auxiliary air intake valve, a

ardest dash pot piston connected with said air in'- take valve and constructed to provide a supplemental piston chamber, a supplemental piston disposed in said chamber, a fulcrum pin mounted on said dash pot piston, and a lever fulcrumed on said pin, said lever being pivotally connected to said supplemental piston and adjustably connected to said fuel valve.

7. In a carbureter, the, combination of a dash pot chamber, a float chamber connected therewith, a fuel nozzle in communication with said dash-pot chamber, a fuel valve con trolling said fuel nozzle, an air intake valve, a main piston mounted in said dash pot chamber, an operative connection between said piston and said fuel valve, and means for establishing connection between said float chamber and said dash pot chamber both below and above said piston.

8. In a carbureter, the combination of a float chamber, a dash pot chamber connected therewith, a main piston in said dash pot chamber, an air valve connected to said piston, a supplemental piston yieldably mounted on said main piston, a fuel valve, operative connections between said fuel valve and said supplemental piston, and a conduit establishing communication between said float chamber and said dash pot chamber above the main piston, said main piston being constructed to provide communication between the supplemental piston chamber and said dash pot chamber above the main piston.

WILLIAM A. EDWARDS.

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