US1800340A - Guide and stem assembly for poppet valves - Google Patents

Description

April 14, 1931. I R. H. DAISLEY GUIDE AND STEM ASSEMBLY FOR POPPET VALVES Fild July 51, 1929 INVENTOR v HMISLY BY f, ATTORNEY 1 in the guide is avoided.

Patented Apr. 14, 1931 UNITED STATES PA T- QF ROBERT H. DAISLEY, OF HIGHLAND PARK, MICHTGAN, ASSIGNOR. T0 .WILCOX-RTOH CORPORATION, OI DETROIT, MICHIGAN, A'GORPORATION OF -MICI-IIGAN GUIDE AND STEM ASSEMBLY FOR PQPPET VALVES Application filed July 31, 1929. Serial No. 382,514.

This invention relates to poppet valves for internal combustion engines and pertains more particularly to a new and useful assembly of a poppet valve and a guide therefor.

The objects of the invention are to improve the accuracy of the sliding fit between the valve stem and the bore of the guide in which it is mounted, to reduce the cost of manufacture of the assembled valve and guide, to protect the rubbing surfaces of the highly polished stem when the valve and'guide are shipped and while they are being assembled in the engine, and to provide a novel and inexpensive construction of the guide whereby the guide can be easily and quickly inserted in the bore of the engine casting and locked in position therein.

My improved valve and guide assembly eliminates the split guide heretofore commonly used in conjunction with valve stems that are upset at the ends remote from the valve head. By eliminating the split guide I reduce the expense of manufacture and in sure more accurate fit of the guide and the stem and reduce the cost of handling, because a one-plece gulde 1s less expensive to manufacture than a split guide, and the bore that receives the stem can be made to a more accurate running fit, and. the liability of nicking or marring thesurface of the bore I attain the foregoing objects by providing in conjunction with the usual poppet valve consisting of the polished stem and head, a guide of bronze or anti-friction metal the guide being made of a single piece of metal very accurately bored to slidinglyreceive the valve stem and made in cylindrical form so as to be received by a straight pressed fit inthe bore of the engine casting. An end of the guide when so received in the casting projects above the casting and there presents a peripheral groove adapted to receive a snap washer that releasably locks the guide and the engine casting together and. also provides a seat for the valve spring.

After the guide has been put in place on the valve stem and before it has been applied to the engine casting, as above described, the valve stem is provided with an enlarged head larged heads have heretofore been commonly used, in connection with the valve stems,

but so far as Tam aware, have not been applied to. the valve stem after a onepiece accurately fitted bushing has been slipped over the stem, thus completing a unitary assembly of the valve and its guide. These assemblies, each consisting'of a guide, a'valve having the usual head and an enlarged end remote from the head, can be conveniently manufactured at a valve factory and can be shipped to the engine plant and assembled in the general way with the ass'urance that the accurate factory fit will be preserved during shipment and after the valve and guide have been put in placerin the engine.

With the 'foregolng and certain other objects in view, which willappear later in the specification, my invention comprises the devices described and claimed and the equivalents thereof.

In the drawings Fig. 1 is a side view partly 7 5 broken away, showing the manner of assembli'ngthe valve and guide.

Figs. 2, 3 and 4 are details showing various ways of applyingthe enlarged end of the stem to provide the spring retainer seat.

jFig.'5 ,is a side view of the completed assembly, showing in dotted lines the application thereto of a snap washer for holding the assembly in place in the engine casting, the

snap washer serving also as a seat for the valve spring. I

As is clearly shown in the drawings, nu-'; merals 1 and 2 respectively indicate the polished valve stem and the valve head, the usual enlarged or upset end 3 forming the spring retainerse-at. Numeral l indicates the one-piecevalvestem guide accurately bored to slidingly receive the stem 1 and accurately turned, and ground outside to form a press fit in the bore of the engine casting, as indicated in Fig. 5. The upper end of the guide 4 where it projects through the engine casting is formed with a peripheral groove 4a and into this groove is secured a snap washer which securely holds the guide in position.

The'head' 3, as shown in Fig. 2, may be formed by a cold or a hot upset, or it may be made, as indicated in Fig. 3, by forming the stem and head separately and then welding them together, or; as shown in Fig. 4 vthe stem may be slipped into a bore 3a oi the head and fastened therein by Welding. in the usual way. i I I In practicing my invention the stem 1 and head 2 are fabricated as is customary, the one-piece bushing 1 is bored, ground and grooved and is then slipped over the stem 1, after which the head 3 is formed by any of the usual methods, such as those just mentioned. Under these conditions of working the stem and guide can be highly polished v and made'to a very accurate sliding fit and this. relationship: can not be disturbed by' subsequent handling as in shipping or in assembling the engine.' The bore of guide 4 is always protected against accidental mar- 1 ring and, alsohelps to protect the highly pol:-

ished stem 1 against injury. No starting; experimentalfitting or other handling is. required at the assembly plant in order to'se' cure an accurate assembly, as has heretofore been the case when split pus-hingshave been used,nand there is no liability of the bushing working out of place when held" by the snap \ent is:

washer" in the manner indicated by dotted lines in Fig. 5.

Disassembling in service is also rendered easier because atwo-piece-bushing heretoforev used is very diiiicult to get out after being: put into" the engine, whereas the one-piece bushing of the present assembly can be removed very easily by detaching the snap. washer, forcing the bushing out.

Having thus described my invention,-what I claim and desire to secure by" Letters Pat 1. A valve and guideassemblycomprising; in combination a valve havingja head and a stem having an enlarged end remote from; said head and forming, tin-integral part or said stem,. a longitudinally bored valve stem guide comprising a single piece of; metal bored longitudinally and sl-idingly received:

on said stem, the external diameter of said I guide being greater than the diameter of said enlarged end, said named par-tsconstituting an assembly adapted for installation in an engine as a unitary piece, forthe pur-- poses set forth. h

2. A valve andbushing assembly as speci- Q fled in claim 1 wherein the guide is'for-Ined;

with an eX-terior peripheral groove nearanend thereof, said groove adapted to receive a snap washer, for the purposes set forth.

In testimony whereof, I affix-my signature I ROBERT H. DAISLEK'

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