US2927566A - Push rod for internal combustion engine - Google Patents

Description

.March 8, 1960 g.. H.. MQYE @uga 1w@ m www@ @@Mugfrm mm@ wilg@ my @en las? IN1/mm2.. amm H, Moy@ FIG@ United States Patent' PUSH ROD FOR INTERNAL COMBUSTION ENGINE Benjamin H. Moye, Warren, RJ.

Application May 29, 1957, Serial No. 662,410

1 Claim. (Cl. 12S-90) My present invention relates to an internal combustion engine and more particularly to a novel push rod for actuating the valves.

The principal object of the present invention is to prt vide a push rod construction which will virtually eliminate the tappet noises from an internal combustion engine.

Another object of the present invention is to provide a push rod construction which will increase the eflciency f the engine.

A further object of the present invention is to provide an improved push rod which can readily be applied to existing constructions.

Another object of the present invention is to provide a novel push rod construction which s easy and economical to assemble and install.

With the above and other objects and advantageous features in view, my invention consists of a novel arrangement of parts more fully disclosed in the detailed description following, in conjunction with the accompanying drawing and more fully defined in the appended claims.

In the drawings:

Fig. l is a Vertical section of a valve and push rod assembly embodying my invention.

Fig. 2 is a similar view with the valve in open position.

Fig. 3 is a perspective view of the converting sleeve,

Fig. 4 is a fragmentary sectional view of another application of my invention.

Certain makes of automobile engines, equipped with overhead valves, are inclined to be noisy. This tappet noise develops between the push rods, the rocker arm and the valve. As the parts wear, the noise increases. Furthermore, the vibration of the engine causes a similar vibration of the valves and a slight leakage of air passes the valve stem and seat. This reduces the vacuum pressure through the carburator and reduces the efliciency of the engine.

The present invention is designed to improve engine performance and virtually eliminate tappet noises. This is accomplished by providing a constant yielding contact between all the parts from the tappet and push rod to the valve.

Referring more in detail to the drawing illustrating my invention, the engine block is provided in the conventional manner with a valve 11 having a vertical valve stern 12 and the spring arrangement 13 for normally retaining the valve in closed position shown in Fig. 1. The valve actuating mechanism comprises the cam 14 on which the vertically extending tappet 15 rides. Extending upwardly from the tappet 15 is a push rod 16. The top of the valve block lil has a shaft 17 which is supported by studs 18 and a rocker arm 19 is mounted on the shaft so that one end 29 bears on the upper end of the valve stem 12. The other end of the rocker arm 19 is provided with an adjustable screw 21 and having a spherical end 22, which rides in a socket 23 in the upper end of the push rod 16. Normally, with the above construction the necessary clearance is provided between the end ofthe arm 19 and the top of the valve stem 12. However, as the parts wear the rocker arm becomes loose on its bearings and no amount of adjustment on the screw 21 will compensate for the looseness of the parts. The engine is then noisy and the valve vibrates.

The present invention provides a construction which is readily adaptable to the existing push rods and which interposes a yielding connection which keeps the various parts in continued contact. Referring again to Fig. 1, the push rod 16 is severed at a point above the engine block 10 so that the upper portion thereof 24 becomes a short length carrying the flared socket 23. A sleeve 25 is provided with a central opening 26 extending into the sleeve from both ends but leaving a solid wall portion 27 intermediate the ends of the opening 26.- The sleeve 25 is positioned over the lower portion of the push rod 16 until the wall portion 27 rests on the top end of the push rod. A coil spring 28 is then slipped over the upper portion 24 of the push rod and the upper portion is now pushed into the upper end of the opening 26 as shown in Fig. l.

The coil spring 28 is preferably provided with a finished lower end so that it will rest llatly against the top of the sleeve 25. The upper end of the coil spring 28 is left free so that it will ride around the flared socket portion 23 which acts as an upper stop for the spring. It is essential that the spring 28 have less tension than the valve spring 13. For example, the valve spring may have a tension of approximately 52 or 53 pounds. in such cases the spring 2S is provided with a tension of approximately 30 pounds. Also the spring 28 is of such length that it will keep the upper portion 24 of the push rod from completely entering the opening 26 leaving a space 29 below the end of the portion 24 and the wall portion 27.

With the construction illustrated in Fig. 1 the spring 23 will retain all the parts in yielding contact with each other. As the cam 14 rotates into valve opening position, as shown in Fig. 2, the tappet 15 and push rod 16 are pushed upwardly and the spring 28 is compressed until the lower end of the rod 24 hits the wall portion 27. From that point on the entire assembly moves upwardly as a solid rod and the rocker arm 19 functions in the normal manner to open the valve 11. Continued movement of the cam will return the parts into the position shown in Fig. 1, and any slack caused by wear of the parts is taken up by the spring 28 so that the parts remain in contact with each other.

I have found that the above construction and operation not only eliminates tappet noises but the contact of the end 20 of the rocker arm on top of the valve stern 12 prevents the vibration of the valve and reduces any leakage through the valve. Tests have shown that the vacuum pressure of the engine is increased thus reducing gasoline consumption,

The above construction illustrates the device applied to a solid push rod. In some engines the push rod 16 comprises a hollow tube. Referring to Fig. 4 the tube push rod 30 is severed adjacent the upper end. A plug 31 is then pushed in the remaining end of the rod. I now provide an auxiliary upper hollow portion 32 carrying the socket 33. The portion 32 is of slightly larger diameter than the push rod 3l). The lower internal end of the portion 32 is provided with shoulders 34 to limit the vertical sliding movement of the member 32 over the push rod 30. A spring 35, similar to the spring 28 in Fig. 1 is positioned inside of the member 32 with the lower end resting on the plug 31 and in relaxed position retaining the shoulders 34 a slight distance above the plug 31. The operation of the device is identical with that of the form shown in Figs. 1 and 2.

In setting the valves, the adjustable screw 21 is pushed downwardly compressing the spring 28 into the position 3 shown in Fig. v2. The screw 21 is then adjusted to provide the necessary valve clearance in the end of the rocker arm 20. The pressure is then released and the parts will assume the position shown in Fig. 1. The assembly of 'the present invention is simple in construction and easy to install. Other advantages of the invention will be readily apparent to a person skilled in the art.

i claim:

A push rod for an internal combustion engine positioned between a earn and the valve operating rocker arm, comprising a lower rod portion resting on said cam, an upper rod portion bearing against said rocker arm, and means for retaining said rod portions in alignment and in yielding contact with said cam and rocker arm, said means including a sleeve having opposed openings, one 15 2,677,358

4 opening receiving said lower rod portion and the other opening receiving said upper rod portion, and an integral wall between said openings, `and a coil spring surrounding said upper rod portion and hearing against said sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 1,443,940 Anderson Feb. 6, 1923 1,607,128 Johansen Nov. 16, 1926 1,613,815 Anderson Jan. 11, 1927 1,905,888 Berry Apr. 25, 1933 2,525,791 Good Oct. 17, 1950 2,564,902 Heuser etal. Aug. 21, 1951 Wright May 4, 1954

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