US1634276A - Tappet for internal-combustion engines - Google Patents

Description

TAPPET FOR INTERNAL COMBUSTION ENGINES Filed June '7, 1924 WITNESS INVENTOR,

Patented July 5, 1927.

UITED STATES WILLIAM STEVENSON, OF MORRIS'IOWN, NEW JERSEY.

TAPPET FOR INTERNAL-COMBUSTION ENGINES.

Application filed June 7,

This invention contemplates an improved tappet for imparting actuation to the valve of an internal combustion engine, the construction being such that the tappet is readily adjustable by a single person, the ordinary tappet usually requiring two persons three hands-to effect its adjustment. The improved tappet includes a' body member, a head member having a screw-thread conio nection with the body member whose axis is lengthwise of the tappet to efi'ect alteration in the length of the latter on turning the head member, and a spring-actuated keeper splined to one of said members, as the body member. and having a disengageable interlock with the other. In adjusting, the keeper is pushed out of engagement with the mem-- ber with which it is interlocked, tensioning the spring, and said member is turned rela- Zll tively to the other member. In order, in

this operation, to impose a desirable brake or drag on the head member and to hold it precisely where it is thus adjusted until the manipulation of the parts is completed by allowing the keeper to return to locking position, the invention also includes means to frictionally resist the turning of said member; this means may also serve, when the interlock is afforded by intermeshing teeth having sloping surfaces, as an auxiliary to the spring-actuated keeper to resist possible turning of said member when the tappet is in action.

In the drawing,

Fig. 1 is a side elevation of the improved tappet and fragments of the cam and valvestem of an internal combustion engine;

Fig. 2 is a view of the improved tappet mainly in vertical central section:

Fig. 3 is a side elevation, partly in section, and underneath plan of the head member;

Fig. 4: is a top plan, vertical section -and underneath plan of the keeper;

Fig. 5 is a plan of the body member; and

Fig. 6 shows a part of the means to frictionally resist turning of the head member.

The body member a of the improved tappet is cylindrical and has the usual basal flange a; at its upper end there is a reduced extension a and from its upper end.

extends downwardly through the extension a bore 6 closed at the bottom and internally threaded. The extension is flattened, preferably at opposite sides, as indicated at a proper 0 to receive a wrench and an axial The head member 0 has a hexagonal headv 1924. Serial No. 718,433.

threaded depending stem 0 It also has a depending flange c spaced from the stem and serrated at its edge.

(Z is the keeper consisting of a 'disk having an upper peripheral flange d serrated at its edge and formed at its lower side with a recess 03 The disk has a central hole d formed with two opposite straight sides, as shown in Fig. 4:, and being otherwise shaped the same as stem 0 in plan.

e is a spiral spring of a diameter to be received in the recess (Z and receive the extension a of said body member.

The foregoing parts are assembled as shown in Fig. 2, the head member having its stem screwed into the extension of the body member, and the spring and keeper being fitted over said extension and the former bearing against the enlarged lower part of the body member and holding the flange of the keeper bearingagainst the flange of the head member with their serrations or teeth interlocked with each other.

The tappet being positioned in'the engine between the stem '5 ofa valve and a cam 7' for actuating the valve, adjustment of the height of the tappet is eflected by depressing the keeper until the teeth thereof and of the head 0 clear each other and then turning the head with a wrench applied to its head proper 0. Since the keeper is in effect splined to the body member (1 because its hole d fits the flat-sided extension (1, of the body member, when the keeper is now released so that its teeth interlock with those of the head member the keeper will hold the head member where adjusted.

The lower end of the stem 0 has a conical recess f and may be split, as at f, in two intersecting planes. This recess receives a conicalplug 9 having a stem 9, the lug being subject to the pressure of a spira spring h interposed between the plug and the bottom of the bore 7) and receiving at its upper end the stem of the plug, as shown in Fig. 2. This means for imposing frictional resistance to the turning of the head member is desirable in obtaining a nice adjustment of, the latter, which otherwise might 105 be inadvertently turned more or less one Way or the other after the adjustment has been effected but before the keeper is released to lock the head in position. It also serves, especially where the surfaces of the teeth or serrations are inclined, as an auxiliary to the keeper in holding the head against turning I what I claim as new and desire to secure Letters Patent'is as an incident of the reciprocating motion of. the tappet when :in action. Good frictional resistance is obtained by recessing and splitting the stem as described, and to this end the taper of the plug 9 should be such as to cause expansion of the split portion of said stem.

Having thus fully described my invention,

1. An engine tappet including'a body member, a head member having a threaded connection with the body member, spring including means, interposed between said members and acting lengthwise of the tappet, to releasably hold the head member against turning relatively to the body memher, and a friction brakemeans interposed between said members.

2. An engine tappet including a body member, a head member having a threaded connection with the body member, springin said recess and a spring interposed betwen said plug and the other member.

In testimony whereof I affix my signature.

WILLIAM STEVENSON.

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