US1815134A - Expansion compensating device for valve actuating mechanism - Google Patents

Description

xmscmmlsux4 l July 21, 1931. J. wElNER ET AL EXPANSION COMPENSATING DEVICE FOR VALVE ACTUATING Filed Nov. 21, 1928 @magali fil/ias lf2! f' cff- 50127116/ Z5. L/al' .oMu

Patented July 21, 17931 UNITED STATES PATENT OFFICE JU'IIIUS WEIN'ER, OF PHILADELPHIA, PENNSYLVANIA, AND SAMUEL IB. SKLAR, OF

MINNEAPOLIS, MINNESOTA EPANSION COMPENSATING DEVICE FOR VALVE AGTUATING- MECHANISM Application filed November 21, 1928.

y lOur invention relates to internal combustion engines and has for its object to provide a simple and highly efficient expansion compensating device for valve actuating mechanism.

The aims of the invention are to hold the tappets of an internal combustion engine in contact with the valve stems at all times thereby eliminating valve taps and to compensate for expansion under varying temperatures, vvhichwould change the relation of the valve stems in respect to their actuating mechanism and prevent the valves from being held open to the burning thereof.

To the above end, generally stated, the invention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a fragmentary view of an internal combustion engine having the invention embodied therein;

Fig. 2 is a fragmentary detail View with some parts sectioned on the line 2-2 of Fig. 1, on anenlarged scale; Y

Fig. 3 is an enlarged view of the cam and tappet, as shown in Fig. 2;

Fig. 4 is a fragmentary detail view principally in section taken on the line 4-41 of Fig. 3;

Fig. 5V is a side elevation of the shoes, as

shown in Fig. 2, removed from the cam;

and

Fig.` 64 is a view of the cam as shown in Fig. 2'with the shoes removed.

f the parts of the multiple cylinder en- 40 gine illustrated in the drawings, it is iinportant to note the exhaust and intake "valves 7 and 8, respectively, valve stem guides 9, valve springs 10, valve spring seats 11, valve lifter adjusting screws 12,

y lock nuts 13, valve lifters or tappets 1-1,

cam shaft 15 and cams 16 integrally formed with said shaft. The parts thus far Vdescribed are of standard and well fknown construction.

It may be here stated that in the present said calks.4 17 have the same contour as the cam 16 and Serial No. 320,864.

arrangement of the above described parts the tappets let rest directly on the cams 16 and when on the low portions of said cams the valves are held closed by the springs 10 and when on the high portions of the cams 16 the valves are held open by said cams. To insure the closing of the valves it is necessary to leave clearance between the valve lifter adjusting screws 12 and the stems of the valves. If this clearance is such as to make the action of the tappets la very quiet the valves due to expansion will not always close with a result of poor compression and the accumulation of carbon on the valves which often results in the burning thereof. On the other hand, if the clearance between the valve lifter adjusting screws 12 and the stems of the valves is such as to insure the closing of the valves under all conditions of i the engine whether cold or hot, the tappets will be very noisy and subject to agreat deal of wear.

Referring now 1n detail to the expansion compensating device, there being one for each cam 16, the same includes a pair of segmental Vshoes 17 hingedly connected at 1S for circumferentially expanding and con- 17 are inturned calks 20 which extend into seats 2l in the end portions of the retaining groove 19. The outer faces of the calks 2O extend in the same plane and whichplane is 'perpendicular to a line extending from the apex of the cam 16 through the axes of the cam shaft 15 and hinge connection 18. Said calks 2O at their inner faces are beveled and the seats 21 have the saine general shape as The outer surfaces of the shoes their thickness is less than that of the ret-aining groove 19.

A leaf spring 22 yieldingly holds each raised in the retaining groove 19 so that its outer face extends outward thereof, as best shown in Figs. 3 and 4. The springs 22 extend longitudinally in the retaining groove 19 and are intermediate'ly secured by a pair of circumferentially spaced screws 23 to the cam 16.

The ends of the springs 22 are shaped to form small substantially round open secondarysprings 124. r@Fliese secondary springs 241- are removably mounted in open segmental seats 25 in the bottoms olf the Ashoes 17. Said seats 25 .are slightly more than semi- .circles so that it lis necessary to contract the secondary springs 24 to force the same into said seats or remove the same therefrom. The tension Aof the springs A22 Ais such vas to hold the shoes 17 radially projected outwart `of the periphery of the low portion of the in which the tappets 14; are raised Vwith the valve lifter adjusting screws 12 in contact with the stems of the valves said tension is not sufficient Vto interfere with the action of the springs A10 in holding the valves closed.

From the above description, it is evident that the springs 22 always hold the valve 'lifter adjusting screws v12 cin-contact with the valve stems thus eliminating valve taps and permit the shoes 17 yto yield and compensate for expansion and wear. The retaining groove 19 holds 'the shoes 17 against `lateral movement in respect to the cam 16 and the calks 20, by their engagement with the seats 21 hold said shoes against .circumferential movement in said groove. As vthe tappets 14 move from the shoes 17 onto the .high

portions of the cams 16 vto open the valves or as they move from'said high .portions `of the cams 16 `onto .the shoes 17 .the springs 22 lwill permit slight `rocking movement .of said shoes and the hinge connection 18 will also permit 4independent movements to the .slices 17 inrespect .to each other.,

Incase it is necessary toreplace or repair the shoes 17 they may be readily detached from the springs 22 and at which time said springs may be replaced `by a new Vone if necessary.

The above described device ymay .be-.of material assistance inrjproperlyseating valves after they have been ground by making the following adjustment, to wit:

When the motor is warm press down the pushrod in Fig. 13 with the fingers and test with a filler gauge between the valve stem and pushrod allowing sufficient clearance for factory specification 1of the car. Upon releasing the device the pushrods and valve vstems will be kept in the proper positions. rllhis device may also `be of material -assist-ance in locating sticking valves for the reason that when a valve sticks, said device will make a valve tap and thus 4,assist in locating the trouble.

Vlhat we-cla'im is:

1. An expansion compensating device comprising a cam, said cam having a groove therein, a -pair of .shoes mounted said groove, leaf springs secured tothe cam in 'the Abottom of thev groove, Vand the end por- .tions of each spring .engaging a .shoe .and Ayieldingly holding the same projected outwardly of the cam.

A2. The structure .defined in claim 1, said shoes each 'having a plurality of spring seats therein, and secondary springs on the ends of said leaf springs and removably mounted in -said spring seats, whereby each shoe is detachably .connected 1to said cam.

3. The structure defined in dlaiin 1, said shoes 'having a plurality of spring `seats therein, and secondary springs on the rends of said leaf springs and removably mounted lin said seats, said ,secondary springs 'being com-pressible .during their movement into and out of said seats.

e. The combination lwith a cam .adapted to be used in an internal combustion engi-ine and having a circumferentially extending groove therein, of an vexpansion compensating device comprising .shoes mounted in said groove, means .for yielding-ly urging each shoe outwardly of said groove, means for holding each shoe against ,circumferential movement relative to the cam, and Ameans for detachably connecting said shoe to :each cam.

5. The combination Adei-ined in claim 4, .said shoes .comprising :a pair of hingedly .connected segments. j

6. A cam adapted for use in an internal combustion engine, said cam comprising a body portion and .an .apex portion, said body portion being pro-vided .with a circumferentially .extending groove, the .end h,p0rtionsof said groove merging into a -pair of inwardly .extending seats, shoes mounted in said groove, an inturned calk at an end of each shoe and extending into said seats, means yieldingly holdingzeach vshoe projected outwardly of said.grooveand means detachably connecting said shoesftosaid body portion.

7. The combination with a cam having-an apex and a .circumferentially extending groove terminating short of said apex, of a pair of circumferentially extending shoes mounted in said grooves, a hinge connection for said shoes diametrically opposite said apex, means for holding said shoes against relative circumferential movement with respect to said cam, a spring urging each shoe outwardly of said groove, and means detachably connecting said shoes and cam.

8. A cam having an apex and a circumferentially extending groove terminating short of said apex, circumferentially extending shoes coextensive with said groove and mounted therein, spring means holding each shoe projected outwardly of :saidV groove, and means connecting said shoes and cam.

9. The construction defined in claim 8, each shoe having a plurality of seats therein, and said connecting means comprising a plurality of secondary springs mounted on said spring means and adapted to removably extend into said seats.

In testimony whereof we aHiX our signatures.

JULIUS WEINER. SAMUEL B. SKLAR.

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