US1495377A - Gas-engine valve - Google Patents

Description

J. W. BLOOD GAS ENGINE VALVE Filed June 10 1921 Qwuentoz Jase o W310? Patented May 27, 1924.

JOSEPH W. BLO'OI), LONG BEACH, CALIFORNIA.

GAS-ENGINE VALVE. v .1

Application filed l'Iune 10, 1921. Serial No. 476,499.

To all whom it may concern:

Be it known that I, Josnrrr W. BLOOD, a citizen of the United States, residing at Long Beach, in the county of Los Angeles and State of California, have invented new and useful Improvements in Gas-Engine Valves, of which the following is av specification This invention relates to a valve for internal combustion engines and particularly pertains to a tapered oscillatory valve that is moved from its seat when moving to and from its closed position.

An object of my invention is to provide a turnable valve particularly adapted for use either as an inlet or exhaust valve of an internal combustion engine in which means are provided for eliminating friction and Wear ordinarily incident to such valvesembodying means whereby the valve may be maintained in an unseated position when turning to be disposed in its opened and closed positions and caused to become seated when in its closed position.

Another object is to provide a rotary valve for the purpose specified which may be readily removed and replaced without the necessity of removing the engine head or the valve casing, and which will permit the valve being removed while the engine is hot should occasion require.

A further object is to overcome an undesirable feature common to valves of the poppet type, namely, the accumulation of carbon on the contact surfaces of the valve and valve seat when the valve is open to exhaust, which is effected in my invention by the provision of a rotatably mounted cylindrical valve having an elongated longitudinally extending slot openingdiametri cally therethrougli adapted on turning the valve to open and close a passage through its casing whereby the contacting surfaces of the valve and its seat are maintained free of carbon. l l f Other objects will appear hereinafter. The invention is illustrated in the accompanying drawings, in which Figure 1 is a view in section of the valve applied toan internal combustion engine cylinder as seen on the line 11 of Figure 2. Figure 2 is a view in section as seen on the line 2-2 of Figure 1.

Figure 3 is a view in end elevation of the valve when in its closed position.

Figure 4 is a view in end elevation of valve in its open position.

Figure 5 is a view in horizontal section as seen on the line 55 of Figure 1.

More specifically, 6 indicates a valve casing adapted to be secured to an internal combustion engine cylinder 7 which-casing is provided with an intake passage 8 and an exhaust passage 9 leading from the exterior of the casing to thechamber 10 in l the engine cylinder above the engine piston 11. The passages 8 and 9 are elongated and extend substantially throughout thewidth of the chamber 10 on opposite sides the center thereof. Extending transversely through the valve casing are openings 12 and 13 the walls of which conform to and provide seats for turnable valves 14 and 15 arranged in the openings 12 and 13 and extending longitudinally across the passages 8 and 9; the valve 14 being provided with a longitudinal slot 16 and the valve 15 being provided with a longitudinal slot" 17 adapted to register with the passages'8 and 9 when the valves are turned to their open positions.

The outer end of each valve is formed with a flange 18 which seats on a shoulder 19 formed on the margin of the outer end of the valve receiving opening and the inner end of the valve has a reduced portion 20 which projects beyond the valve seat and is fitted with a collar 21. A coil spring 22 encircles the reduced portion 20 and bears between the valve casing and the collar 21 to exert an inward pull on the valve and has its outer end affixed to the valve and its inner end ailixed to the valve casing to yieldably oppose turning of the valve in one direction and to assist in turning the valve in the op posite direction in restoring the valve in a normal position; The outer end portion of each'valve extending between the flange 18- andya point spaced from the outer end of the slot 17 is cylindrical in form, as indicated at 23 in Figure 1, and the portion of the valveextcnding throughout the length of the slot and for a distance beyond each end thereof is tapered, as indicated at 24 in Figure 1; the walls of .the valve receiving opening being formed to conform to the valve. The

spring 22 in exerting an inward pull on the valve serves to normally maintain the valve in its seated position with the tapered the portion of the valve closely fitting the encompassing tapered wall. The collar may be attached to the end of the valve by screw threads whereby it may be adjusted to vary the tension of the spring 22 in which event preferably comprises a castellated nut adapted to be engagedby a cotter pin 25 to pass through an opening in the end portion of the valve as is common in fastenings of this character.

Each valve is formed at its forward end with a smooth face 26 which provides a bearing surface for a cam 27 pivotally mounted on a pin 28 fixed to the valve, which pin is formed with an end flange 29 extending over the outer face of the cam. A wrist pin 30 is mounted on the cam to which is connected a pitman 31.

Mounted upon the valve casing is a roller 32 which is disposed at right angles to the cam and is positioned to bear against the inner face of the'latter; the roller normally extending into an arcuate detent or recess 33 formed on the cam when the cam is disposed in its retracted position as shown in Figure 3. The detent is of such depth that when disposed opposite the roller the bottom wall thereof will be out of contact with the surface of the roller and afford a clearance to allow the valve to become seated.

The cam 27 as explained is free to pivot upon the pin 28 but is adapted to carry the valve with it as it revolves through the medium of a lug 34 which projects from :the end of the valve and extends into a notch 35 provided in the cam. The notch is recessed in the outer perimeter of cam so that faces 36 and 37 are provided at each end of the notch and spaced apart a distance greater than the width of the lug so that clearance exists between the lug and the faces. The tension of the spring holds the plug in its closed position against a stop 38, which is fixed to the valve casing and againstwhich the lug 34 abuts to limit retracted movement of the valve.

The operation of the valve is as follows: When in the normal closed position as shown particularly in Figures 1 and 3, the lug 34 abuts the face 36 of the notch and the roller 32 is in the detent 33 of the cam so that the spring 22 holds the valve tightly on its tapered seat. The pitman is given a proper reciprocating motion through a short arc to impart a rotary motion to the cam.

In the closed position of the valve the wrist pin 30 is disposed a few degrees below the horizontal center line of the valve and on upward movement of the pitman raises it to a point a few degrees above the center line so that the center of the pin moves substantially in a vertical path so that the upper end of the pitman swings through an arc of very slight degree and its movement is substantially vertical.

As the cam 27 turns, the roller immediately acts upon the face of the detent or recess therein causing the valve to be retracted slightly from its seat with the result that the valve will be so positioned relative to the seat that it may be turned without friction. As the cam moves forward the face 36 moves away from the lug 34; the cam continues to rotate without turning the valve until the detent is carried past the roller. The width of the notch is such that the other face 37 does not contact with the lug until the valve is well retracted from frictional engagements with the seat. When the face 37 however comes against the lug which is substantially an integral part of the valve, the valve will then be carried around with the cam, and the slot in the valve brought into alignment with the passages in the valve casing to allow escape of products of combustion or intake of mixture as the case may be. It will be observed that the amount of clearance required to eliminate frictional contact of the tapered portion of the valve with the seat, is very slight and need not be sufficient to allow the escape of the gas along the surface of the valve.

In the open position of the valve as shown in Figure 4, the lug is held against the face 37 of the notch by the tension of the spring 22. As the pitman begins its retrograde movement the tension of this spring tendsto return the plug to its original position without the aid of the pit man. The spring causes thev valve to follow around on the retrograde movement with the cam and finally brings the plug against its stop 38. During the interval the face 37 of the notch is in contact with the lug. When the valve has returned to the stop the cam continues moving toward its normal position allowing the valve to be drawn by the spring down upon its seat. It will be observed that during the interval between the return of the valve to its normal position and the return of the cam to its normal position lost motion exists while the face 37 of the notch is being advanced relative to the lug. When the complete oscillation of the parts as just described is completed all parts are again in the original relative positions as shown in Figure 3. The lost motion created by the gap between the lug and the faces of the notch permit of the valve being retracted from its seat before being turned and on the return movement of the pitman permits of the spring returning the plug to its original position relative to the passage before it is allowed to be drawn down upon its seat.

Whereas I have shown and described a specific embodiment of my invention 1 do. not limit myself to the exact details of construction shown but mayv employ other constructions and arrangement of parts, without departing from thespirit of the inven-

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