US1188405A - Overhead valve mechanism for engines. - Google Patents

Description

A. 'Pf BR'SII'I' OVERHEAD VALVE MECHANISM FOR ENGINES.

APPLICATION FILED MAY 22,1915.

. `riginal application tiled November 30,

' To all whom t may concern.'

PATE orme A L'ANsoN P. ausnjonnnrnor'r, MICHIGAN'.

Be it known that I, ALANsoN P. BRUSH, a citizen of the United States, residing at Detroit, in the 'county of Wayne and Statev of Michigan, have invented va certain new and useful Improvement in Overhead Valve Mechanism for Engines, of which the following is a full, clear, and exact description.

This invention relates to so-called overhead valve mechanism for engines, especially internal combustion engines. Such stem, a spring for movingthe valve up to its seat, a rocker which is pivoted between its ends, and which, at its ends, respectively engages the upper end of the puppet valve stem and the upper'end of an endwise movable push rod. This push rod is actuated by a cam on thecam shaft, which sometimes engages directly with the lower end of the push rod 4and sometimes with what is known asa tappet rod. When the tappet rod is -used, its upper end engages with and supports the lower end of the push rod, so that the t-wo rods are in effect a single push rod. Itis not customary to connect the upper end of the push rod with the rocker, or the rocker with the valve stem, 'because there must be.

some lost motion between the parts of this train of valve operating'mechanism. Sometimes this lost motion is referred to asa valve clearance. If this clearance or lost motion is too much or too little the valve action is relatively unsatisfactory. Usually the push l rod is made so that its length can be varied. r

In fact, one of the reasons for making this push rod of two parts, as shown, isto facili! tatethe varying of the effective length of the push rod.

There is a serious objection to the above mentioned construction, in so far as itsadjustability is concerned, growing out of the v fact that the adjustment can only be effected when the engine is not running; and, also, because one can not determine whether the proper adjustment has been arrived. at unless the engine is runninl Therefore, any

OVERHEAD VALVE MECHANISMCFOR ENGINES.

Specification of Letters Patent. Patented June 2?, 1916.

1914, Serial No. 874,607. Divided and this application filed May 22, 1915. Serial No. 29,743. Y

tion is t0 enable a person to adjust a part of this train of valve operating mechanism while the engine is running.

Other objects of the invention are to provide a more satisfactory rocker .for the puppet valve; to provide means for insuring the lubrication ofthe rocker fulcrum; to pro-A videa fulcrum for said rocker that will al low the rocker to extend in any desired direction therefrom; and to generally improve overhead valve mechanism.

The invention consists ,in the construction and combination of parts shown in the drawing and hereinafter 'described and pointed out definitely in the appended claims. l f

lInthe drawings, Figure 1 is a vertical section of an internal combustion engine mechanism, maybe of any desired construction; and the valve mechanism itself may be of the usual construction except as to the lrocker and the manner of pivoting it.

Referring'to the parts 'by reference characters, 10 lrepresents a puppet valve having an upwardly extended stem 11, which valve is moved upward to its seat 13 by means of a spring 12. 14 represents the cam shaft of said engine and o n this shaft are as' many cams 15 as may be required.

16 represents the endwise movable valve pushrod. In the construction shown this is made of tw'o parts, viz., the push rod proper, andA a tappet rod 16a, which is in effect a 'downwardextension of the push rod. This tappet rod may carry a friction roller 18 which engages directly with the associated cam, and it may have a socket 16b in its upper end to receive the lower end of the push rod proper, whereby the two parts of the push rod are held inoperativel alineme'nt.

2O represents a rocker, and, obviously,

' there must be a rocker for each valve and its associated valve ush rod. Each rocker env valve push rod. The fulcrum for this rocker is about midway betweenits ends, and it is so constructed that it may beadjusted whileV the rocker is in operation, ln the yspecilic construction shown, this rocker has in its upper surface, and about midway between its-ends, a spherical socket a. The fulcrum for-this lever is-.a stud 21, which is ad'ustably fixed tov an overhead support 22, an has a spherical lower end 21a which kfits in said spherical socket. ln the specific construction shown, the part which supports this fulcrum is a cap 22, which is removably secured to the upper end of the engine over the valves. The stud 21 screws down through a threaded hole in this cap; and, as stated, its inner end engages in saidv spherical socket, while its upper end, being above the cap, adords means for turning it and thereby causing it lto move up and down, as required. rlhis ,stud forms a onewa bearing for the rocker, and 1t `has several a vantages over any other form of one-way bearing which might be l :substituted for it. lt is obviously not an eX- lpensive bearing, 'nor does it require any eX- pensive additions tothe engine itself toenable it to be adjustablycarried thereby. lt, likewise, permits the rocker toextendin any required direction from the valve stem to the valve push rod,-that is to say, it need not extend in a vertical plane at right angles to the crank shaft, but may` extend in an oblique direction thereto as it does when used with the multi-cylinder il-type internal l:ombustion engine, which forms the subject matter of my application, Serial No. 87 4,607 filed Nov. 30, 1914, of which this application is a division. This fulcrum stud may be hollow, whereby it may serve as a lubricant well into which a lubricant may be put through its'upper end; and in that event a :ap 23 may be'screwed onto the projecting end of said studto keep out the dirt. ln that event, also, one or more openings 21" should be made through the s herical lower endo fthis stud through w ch lubricant may run directl onto the engaging surface of said'stud an rocker.

It is to be noted that the rocker is a proximatel U-shaped in cross section.

shall be a sheet metal stamping. At the ends of the rocker the lower surfaces which engage the valve stem and ppsh rod, respectively, should preferably as shown. l

ln order that the rocker may not turn on the axis of the fulcrum stud, and so move out of engagement with the valve stem and push rod, al slot 20d may be made through that end of the rocker which engages the push rod; and the upper end of the push rod may go through this slot. In that event the push rod should lbe formed with a flange 16d a short distance below its-end forthe lower surface of the rocker to engage with. Having described my invention, l claim:

.ecause of this shape it is possible that the rockere made convex,

aisance 1. lin overhead valve mechanism for engines, the combination of a puppet valve having a stem, a valve rocker operator, a valve rocker which, adjacent its ends, engages said valve stem androcker operator respectively, which rocker has between its ends an open top fulcrum recess, an overhead support, and a fulcrum piece having its lower end fitted to said fulcrum recess, which fulcrum piece is adj ustably connected with said overhead support.

2. ln overhead valve mechanism for engines, the combination of a spring actuated puppet valve having a stem, a valve push rod, a valve rocker which, adjacent its ends, engages said push rod and valve stem respec tively, which rocker has in its top surface and between its ends an open top fulcrum A recess, a fulcrum member, a support for said f gines, the combination of a spring actuated puppet valve having a stem, a push`rod, a rocker which, adjacent its ends, engages said valve stem and push rod, and which has in its upper side an open top fulcrum recess between said ends, a removable cap for protecting said valve operating mechanism, and a fulcrum piece which is threaded through said cap and which extends downward there` from into thefulcrum recessn of said rocker.

4. In` overhead valve mechanism for engines, the combinationof a puppet valve havinga stem, a spring for closing said valve, a rocker which has a spherical recess in its upper surface and which at one end engages the upper end .of said valve stem, a spherical ended fulcrum stud which engages inlsaid socket in the rocker, an overhead support with which said `fulcrum stud is adjustabl connected, and means for rocking said roc er. i

`5. ln overhead valve mechanism for enines, the combination of a puppet valve aving a stem, a spring for closing said valve, a rocker'which at one end engages the .upper end, of said valve stem and .has a spherical socket in its uppersurface, a 'studsupporting member above saidfvalve, a fulcrum stud which screws through-'said' support and 'has a 'spherical lower end whichv engages in said spherical socket, anda ush :rod which enga es the under .side o the other end of sai rocker. j

6. ln overhead valve mechanism, the combination of a puppet valve having a stem, a spring for closing said valve, a fulcrumed rocker which at one end engages the uppper end of said stem and has a spherical socket in its upper surface, a. fulcrum stud which :lee

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has a spherical end that engges in said` spherical socket and contains a lubricant well and has a hole leading therefrom directly through the rocker-engaging sphericall end of said stud, and a push rod for operai.- ing said rocket. In testimony whereof, I hereunto aliix my Signature in the presence of two wit,

nesses. A v

ALANSON P. BRUSH.

" Witnesses:

E. L.' THURSTON,' L. I. PORTER.

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