US2030345A

US2030345A - Valve actuating mechanism

Info

Publication number: US2030345A
Application number: US2195A
Authority: US
Inventors: Victor F Zahodiakin
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-01-17
Filing date: 1935-01-17
Publication date: 1936-02-11
Anticipated expiration: 1953-02-11

Description

VALVE ACTUATING MEcHAN-Ism 'Filed Jan. 17, 1935 l mi i NVENT'OR I i l y BY MM ATroRNEYs PatentedFeb. 11, 1936 UNITED STATES.l

PATENT OFFICE v 2,030,345 vALvE AcTUA'r-ING MEcnANIsM victor F. zahoaiakin, New York, N. Y. Application January 17, 1935, serial No. 2,195

' 12 claims. (ci. 12a- 9.0)

This invention relates to internal combustion engines and is particularly directed to improvements in the mechanism for actuating the valves thereof. It has been necessary to provide Work- 6 ing clearance between the valve and the valve actuating mechanism to accommodate for expansion because of heat Vsuch as occurs in the normal operation of an engine. Because of this clearance, considerable noise and vibration occur in the operation of the valves.

It is therefore, the object of this invention to provide a simple and efficient valve actuating mechanism which provides for a predetermined amount of lost or idle motion, for permitting exl5 pansion of the parts, instead of the usual clearance, and which at the same time automatically maintains the parts of the actuating valve mechanism in constant contact with each other.

It is a further object oi this invention to provide an improved valve operating mechanism permitting expansion of the parts, which operates the valves without noise, vibration, impact, or A excessive wear of the contact surfaces.

It is a still further object of this invention to provide a device which may be conveniently and quickly installed in the valve operating mechanism without a change in the structure thereof and which will add substantially no additional reciprocating weight to the mechanism.

3o It is a still further'object of this invention to provide a device-of this character in the operating mechanism of the valve so arranged as to permit the normal operation of the engine .in the event of the failure or breakage of the device.

` It is a further object of the invention to provide a device of this character which operates to take up the clearance by a sliding operation,

entirely eliminating impact on the operating parts of the mechanism and entirely eliminating the usual springing or disalignment of the push rod, the latter beingan advantage particularly in the overhead type of engine valve which employs a relatively long push rod.

Other objects and further advantages will be more fully apparent from the detailed description of the drawing, in which:

Figure 1 is a vertical sectional fragmentary' view taken through an internal combustion engine so as to fully illustrate a valvev and its operating mechanism.

Figure 2 is a top plan view of the device of this invention inserted between the rocker arm and the push rod.

Figure 3 is a sectional view taken on line 3 3,

Figure'Z. 1 y

Figure 4 is a vertical sectional -fragmentary view of a portion of the engine illustrating a modified arrangement of the present improvement relative to the push rod.

Figure 5 is a detailed fragmentary View show- I ing brackets 23 (one of which is shown).

ing a modified form oi the device incorporated in the connection between the rocker arm to the push rod.

Figure 6 is a bottom view of the contact element of the rocker arm of Figure 5. 5

Figure 'I is a top planiview of the upper or contact end of the push rod.

Referring to the drawing the engine is generally indicated at I5. For the purpose of the present illustration, only portions of the cylin- 10 der block I6 and the engine head I'H are shown. One of the valves is illustrated at i8, operating relative to a seat I9 for controlling the ow of the exhaust gases from the cylinder bore 2t through the exhaust Apassageway 2l. A rocker l5 arm shaft 22 is mounted on the engine, in bearv The valve operates in a guide 24 and is held against its seat by means of a compression spring 25 held under compression between a. cup shaped 20 disc or retainer 2S, on the upper end of the valve stem and the top of the engine head.

One end of the rocker arm 2'! engages the upper end of the valve stem and the other end includes a contact screw 28 engaging the upper 25 end of the push rod 29 operated from the cam shaft 30. The lower end of the push rod is socketed-in a bearing element 3i slidably mounted in a portion 32 of the engine. The cam 33 in engagement with the lower contact end of the 30 slide bearing is adapted to reciprocate the push rod.

The conventional clearance provided in` the op erating mechanism is from Aapproximately .008 to .015 of an inch. This clearance is provided 35 between the cam and the upper end of the valve stem, that is to say, when the compression spring is holding the valve firmly on its seat this clearance is available for the purpose of permitting expansion such as occurs due to heat generated 40 in the engine during the operation thereof. Now, in the present invention, instead of the provision of this clearance, a lost or idle motion is permitted with the working parts maintained in constant contact through the interpositioning of an element between the push rod and the rocker arm.

The contact screw'd of the rocker arm is adjustably mounted therein and is held in place by means of a nut 34. The lower end of the contact 50 screw is in the form of a ball 35 which ball is disposed within and in contact with a socket St on ythe upper end of the push rod.

The element 37 which is interposed between the rocker arm and the push rod may be de- 55 scribed as a spring clip normally under compression. Its expanded position is fully illustrated in detail in Figure 3. It consists of a cylindrical portion 38 and arms 39 and it projecting parallel with repectve radial lines taken from the center tu of the cylindrical portion. These arms include circular openings'4l and 42. The margin of the opening in the lower arm is provided with a series of downwardly pressed tangs 43, four in this particular case, spaced at 90 degrees apart. 'I'he axes of these apertures 4i and 42 are not coincident but rather will be noted as onset from each other. The tangs which are pressed downwardly from the lower arm provide means for properly centering the elementen the upper end of the push rod as shown in Figure 1, by engagement around the socket portion and prevent lateral displacement of the clip element, when in position.

In assembling or interposing the device of this invention the normal' clearance is provided as in the old apparatus. This clearance is shown between the lower end of the ball of the contact element andthe bottom of the socket and is indicated at 44. The assembler then raises the outer end of the rocker arm compressing spring 25 of the valve. He then compresses the arms of the clip and inserts the same over the contact stud whereupon the upper arm of the element lies against the under surface of the rockerarm surrounding the contact stud and the lower arm engages over the upper or socket end of the push rod.

The lower arm as stated-will be centered relative to the push rod by means of the tangs and will be in abutment with the under surface of the arm marginally of the opening thereof. When the rocker arm assumes its normal position the spring clip will be in compression, as 'shown in the assembled view of Figure 1.

The clearance 44 thenis more aptly referred to as a means for permitting lost or idle motion since the ball and socket are actually in abutment at certain positions thereof. A

Due to the fact that the openings in the respective arms are not aligned but have their axes offset, the push rod will be disaligned from the contact screw .and the ball or contact end of the screw will lie against the side of the socket. This contact with the side of the socket is constantly maintained due to the fact of the 'disalignment of vthe push rod and it will be apparent that cxpansion can take place due tothe lost motion afforded by the clearance 44.

Instead of this clearance being taken up in the normal manner, in this case, it is taken up through a relative sliding movement of the ball and socket. This entirely cushions the movement and prevents the damaging impacts which occur in the conventional mechanism. In other words, instead of a direct movement across a clearance resulting in a hammer like blow every time the push rod is moved upwardly, the ball rides in contact with a curved surface at all times, as opposed to clearance, and establishes a solid working contact. As the pushrod is moved upwardly the ball moves on a rounded cam surface to a cushioned contact or abutment without shock of any sort. The socket in which the contactv stud is disposed is of perfectly circular form having a radius greater than that of the ball. 'Ihe curved contact surface on lwhich the ball moves can be varied, as desired, that is to say, it can be more gradual or more abrupt.

In the modified form of the invention shown in Figures the same lost motion is permitted by means of an interposed element between the-contact screw and the push rod. A spring 45 under 'tension has its terminals attached to a lug 46 on one side of the push rod and a lug 41 as an intcgral part of the engine body. The sliding bearing 3l has its socket formed on a radius 'greater than the radius of the ball end engaged in it and the same as the radius of the upper socket end of the push rod. Accordingly the push rod is urged laterally bodily by the spring and has its axis disaligned from the axes of the contact stud and the slide bearing resulting in the lateral abutment of the balls and sockets in the same manner as described in relation to the upper end of the push rod in the preceding form.

In the form of the invention shown in Figures 5 .to 7 inclusive, the disaligned relation of the contact stud and the push rodis maintained by means of a clip spring 48 fastened to the upper end of the push rod by means of a rivet 49 and having a rounded contact end engaging the side of the contact ball urging it laterally against the side of the socket. As in the preceding forms it will be noted that in this, the parts as well as the centers are aligned when the operating mechanism is moving the valve from its seat. shown, the contact end of the contact screw may be of rectangular horizontal cross-section and the socket likewise, with the adjacent contact portions of the stud and socket providing curved contact surfaces of rectangular outline.

Having described my invention, I claim:

1. An operating mechanism for the valve of an internal combustion engine, comprising, a spring seated valve, a rocker arm having one end in Contact with the valve, a push rod engaging the other end of the rocker arm, ball and socket contact elements on the rocker arm and push rod, said ball element fitting loosely in said socket element and spaced therefrom axially of the push rod, a c arn for reciprocating said push rod, and a U-shaped fiat spring element lhaving disaligned apertures in its arms engaged over the socket element and the ball element whereby the ball ele- :ment and socket element are urged laterally relatively to contact, said spring element interposed under compression between the rocker arm and the push rod.

2. An actuating mechanism for the valve of'an internal combustion engine, comprising, a spring seated valve including reciprocating means, an element in contact with said valve reciprocating means, a cam lfor reciprocating said element, a socket on the end of said clement, a contact stud on the valve reciprocating means including a ball end disposed in said socket, said socket providing a surface of greater curvature than the ball engaged therein, said surfaces spaced apart assuming that there is no thrust on said element and the socket and stud to be in axial alignment, and spring means for urging the ball and socket laterally relatively, whereby the spring means tend to maintain the ball and socket in constant contact at the sides thereof and lost motion occurs in the first phase of the valve opening movement.

3. An actuating mechanism for the valve of an internal combustion engine, comprising a spring seated valve, a rocker arm having one end in contact with said spring seated valve, a push rod in contact with the other end of said rocker arm, a cam for reciprocating said push rod, a socket on the upper end of said push rod, an adjustable Contact stud in the rocker arm including a ball end disposed in said socket, a socket element having a socket connection with the lower end of the push rod and engaged by said cam, a spring under tension for constantly urging the push rod laterally, and said sockets providing surfaces of greater curvature than the balls engaged therein,

, rod, a cam for reciprocating said push rod, a ball and socket connection between 'seated valve, a rocker arm ing said valve for unseating the distance between the bottoms of the respective sockets being less than the distance between the bottom of the. lower socket and the ball stud on the rocker arm, lwhereby said tension spring tends to maintain the balls and sockets inabutment at the sides of the sockets and lost motion occurs in the first phase of the push rod movement as the balls slide tothe bottom of the sockets for positive operative contact. Y

4.k An'actuating mechanism for the valve of an internal combustion engine, comprising, a springseated valve, a rockerarm having one end engagingisaid valve for operating the same, a push rod', means forreciprocating said push rod, said push rod in'const t contact with the other end of said rocker arm, said push rod having a rectangular socket element on its upper end including a curved bottom, said rocker arm including an adjustable stud therein having an end ntting in said socket, lthe socket bottom being of greater curvature than the curved surface of the stud end, and. spring means for urging the socket laterally against the side of the stud end, said socket and stud end spaced apart axially, whereby upon reciprocation of the push rod toward-the rocker arm, a predetermined amount of lost motion occurs as the stud end slides to positive abutment in the bottom of the socket, whereupon motion is transmitted to the valve. l

5. An actuating mechanisn for the valve of an internal combustion engine,'comprisin'g aspring seated valve, a rocker arm having one end engaging said valve for unseating the same, a push the upper end of the push rod and the rocker arm, said connection incorporating curved contact surfaces, the curvature of the socket being generated on a radius greater than that ofthe ba.lland spring means for maintaining said ball and socket in axial disalignment vwith the stud contacting the side of the socket, the end of the ball and the bottom of thev socket being disposed at different elevations when there is no thrust on the push-rod, whereby as the push rod is moved by the cam said disaligned parts are aligned and positive operating contact occurs.

l 6. An actuating mechanism for. the valve of an internal combustion engine, comprising, a spring having one 'end engagthe same, a push rod, a cam means'for reciprocating said push rod, ball `and socket connections betweenthe upper end of the push rod and the rocker arm and the lower Yend of the push rod and the cam means, saidY connections incorporating curved contact surfaces,

the curvature of the sockets being generated on radii greater than that of the balls, the distance lbetween the bottom o f the sockets being less than urging the push rod laterally and contacting the balls against the sides of the respective sockets.

'1. (An operating mechanism for the valve of an internal combustion engine, comprising, a spring seated valve, a rocker' arm having one end in contact with the valve, a push rod, said push rod and rocker arm having component bali and socket elements respectively, a cam for` reciprocating 'i said push rod, said pushrod being of one piece structure. said parts adjusted to provide clearance, and a device-incorporated in the valve generating constant preswhereby lateral con t'of the ball and socket vin contact with eating said cam follower and the distance between the upper ball and the bot- Y valve' tom of the lower socket, and spring means for element, and a spring for rated in said parts of the valve mechanism forv I laterally displacing said push rod.

9. In a mechanismV for reciprocating a valve including a plurality ofco-axially arranged members and means for intermittently applying an operating force axially to said members to cause one member to operate the other; a means for taking up slack between said members and preserving predetermined lost motion, incorporating adjacent members including sliding contact surfaces, one of said members urged laterally to contact the sliding surfaces, said surfaces being curved, and one curved surface having a radiusr greater than the other curved surface, said lateral urging of one member causing the generation of axial pressure and eliminating of slack in all members of the valve reciprocating mechanism.

10. An operating mechanism for the valve of an internal combustion engine, comprising a spring seated valve, a. rocker arm having one end the other end ofthe rocker arm. a cam follower having a socket, the other end of the push rod comprising a bali end engaging said'socket in operating contact with the cam, and a device incorporated in the valve operating mechanism for generating lateral pressure on thepush` rod, said ball end of said against the side matic take-upfand to permit lost motion.

11.Axi operating mechanism for the valve of anl internal combustion engine, comprising, a spring seated valve, a rocker arm having one end in contact 'with the valve, a cam follower, a. push rod having a'loose ball and socket. engagement with the other end of the rocker arm and with the cam follower respectively, a cam forrecipropush rod, and a device for urging said push rod laterally whereby 'the cam follower. said cam follower being in p ush rod being constantly forced ,A of the followerA socket for autohaving sliding contact for the valve, apush rod engaging v theball and socket joints are in lateral contact y and sliding movement constituting lost motion occurs before axial alignment of the balls and sockets `occursfor driving contact. v

12. An actuating mechanism for the valve ofA an internal combustion engine comprising a spring seated valve, means for reciprocating said an operatnig element in contact with said reciprocating means, a. cam for reciprocating said element, ball and socket contact means between the valve reciprocating means and said element, said ball land socket means having an appreciably loose fit and the end of the ball and the bottoml A of the socket being disposed at different elevations when there is no thrust on the operating urging ythe ball and socket elements laterally relatively whereby the ball and socket elements are in constant contact and lost motion occurs in the rst phase of movement ofl one toward the other as the ball slides to the bottom of the socket.

:moron rl zsnonmnm.