US1372874A

US1372874A - Valve mechanism

Info

Publication number: US1372874A
Authority: US
Publication date: 1921-03-29
Anticipated expiration: 1938-03-29

Description

C. H. ENGLAND.

VALVE MECHANISM.

APPLICATION FILED DEC. 19, 1919.

1,372,874, Patented My 29, 1921.

Fr! ML, 9] W H O 0 R N R o Q \o w i w I VI IIAIIII Bin.

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W I TNESS:

INVENTOR' A TTORNE Y.

UNITED STATES PATIENT OFFICE.

vALvn MECHANISM.

specification of Letters Patent.

Patented Ma1x29, 1921.

Application filed December 19, 1919. Serial No. 348,159.

To all whom it may concern:

it known that I, Cnns'rnn ENGLAND, a citizenot" the United States, residing at Kansas City, in the county of Jackson and State of Missouri, have invented certain new and useful Improvementsin Valve Mechanisms, of-which the following .is a specification. x

My invention relates to improvements in the valve mechanisms of internal-combustion engines and pertains more par icularly to the tappets for openin the puppet valves oi such engines.

In carrying out my invention, I employ a tappet which is constantly held in engagement with. the push rod or the stem of the associated valve, so that it may open said valve without striking the push rod or the stem a hammerdike' blow such as occurs in the usual construction where the push rod or valve stem is spaced from the tappet to allow the valve mechanism to expand without unseating the valve when the engine becomes heated from explosion of the comhustible charges.

Instead ofproviding the usual space above-mentioned between the push rod and the. valve stem, I provide said tappet with yieldable means to automatically take up the expansion and contraction of the valve mechanism and at the same time hold the ta-ppet in constant engagement with push rod or the valve stem wlthout danger of unseating the valve when the parts expand and become slightly elongated from v the heat generated by the explosions, as above stated.

By the use of my invention the tappet and the valve mechanism are not only relieved oithe han'nner-like blows each time the valve is opened, but they are also reform of tappet.

Referring now in detail to the various parts, A designates a cylinder of the valve in the head type. Said cylinder A, has inlet and exhaust valves B and C, respectively. The inlet valve 13 is opened against the action of a spring D by a rocker-arm F fulcrumed at H and actuated by a push rod G, which in turn is actuated by one of the tappets 2 comprising the important feature of the present invention.

.l e exhaust valve C is provided with a valve stem I which is opened against the action of a spring J by one of the tappets 2. The tappets are actuated by the usual inlet and exhaust cams K and L, respectively. Each tappet 2 comprises a stem 4 provided at its lower end with a flange 6 through which a counterbore 8 extends upwardly into said stem lto receive a plunger 10 and a light coil spring 12. The lower end of the plunger 10 has a marginal flange 1 1 adapted to fit in a recess 16 in the bottom of the flange 6. The plunger 10 and the spring 12 are held in assembly with the. tappet 2, by reducingthe upper end of said plunger 10 to fit tightly in the lower convolution of the spring 12 and fitting the upper convolution of said spring in an annular groove 13 communicating with the upper end of the counterbore T he upper end or" the tappet stem d has a threaded counterbore 20 to receive a screw 22 provided with a lock nut 24: to secure it at any point of its adjustment in the counterbore 20. The screw 22 is provided at its upper end with a head 26 having a recess 28 constituting a seat for the lower end of the associated push rod G or valve stem I, as the case may be. As the valve 11180112.-

nisni wears the screw 22 is adjusted up' wardly to compensate for such wear.

After the parts have been properly adenough to lift the associated valve from its seat.

their high radii roll into engagement with the plungers 10, the same are pushed upwardly until the flange 14 is seated against In practice, when the cams rotate and the upper wall of the recesses 16. The high radii of the cams also engage the flanges 6 and lift the tappetsQ, causing them to openv such seating of the flanges 16 will be unaccompanied by either noise or shock.

By providing each tappet 2 with a plunger 1O anda spring 12 to hold said tappet 2 in raised position, the spa ce or clearance usually provided between the head of the screw 22 and the valve stem to allow for expansion of the valve mechanism is unnecessary, and hence said valve mechanism is not subjected to a hammer-like blow each time the tappet is raised by the cam. Furthermore, any play between the valve stem and the rocker-arm and between the rockerarm and. its fulcrum, is automatically taken up by the plunger 10 and the spring 12 and wear on these parts is reduced accordingly. The usual clatter accompanying the operation or the valve mechanism and which is especially objectionable in valves 01 the overhead type. is also practically silenced.

In the form disclosed by Fig. at, the construetiou oi' the tappet is the same as that disclosed by the other figures oi the drawings, as evidenced by corresponding reference'numerals with exponents a, the only diil'erence being that the screw 9 and its lock nut Qal are dispensed with, so that the upper end of the 'tappetstem may be arranged in actual contact with the push rod or the valve stem. V

i From the foregoing description, it is apparent that I have produced a tappet embodying the advantages above-pointed out,

and while I have shown and described two embodiments of my invention, I reserve the right to make such other mod fied forms as properly fall within thespirit and scope of the claims.

Having thus described my invention, what- I claim and desire to secure by Letters Pat- 7 than the adjacent end of said tappet to bear against the cam, and a spring interposed between the upper ends of the counterbore and the plunger to hold the same in engage ment with the cam and also allow said plunger to move into the tappet, so that the cam may engage and lift said tappet,- substantially as described.

2. In combination with a puppet valve mechanism and a cam to actuate the same, a tappet interposed between the valve and said cam and having a counterbore with recesses at each end, a plunger slidably mounted in said counter-bore and having a flange hearing upon the cam and adapted to operate in the recess in the adjacent end of the counterbore,.and a spring in the counterbore having an enlarged convolution at one end disposed in the inner recess of the counterhore and a convolution at its opposite end firmly embracing the adjacent end of the plunger to hold the flanged end thereof in engagen'ient with the cam and also hold the plunger and said spring in assembly with the tappet, substantially as shown and described.

In testimony whereof I affix my signature, in the presence of two. witnesses;

. CHESTER H. ENGLAND.

.Vitnesses F. G. Frsonna, L. J. Freer-Inn.