US1161406A - Push-rod for engines. - Google Patents

Description

J. W. NILSON.

PUSH ROD FOR ENGINES.

APPLICATION FILED MAR. 16. 1914.

1 ,1 1 AM. Patented Nov. 23, 1915.

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JOEL W. NILSON, 0F DETROIT, MICHIGAN.

PUSH-BOD FOR ENGINES.

Specification of Letters Patent.

Application filed March 16, 1914. Serial No. 824,915.

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My invention relates to an improved push rod for operating valves of internal combustion engines.

In internal combustion engines the valves are generally operated mechanically by means of push rods interposed between the cams of the cam shaft and the valve stems, and as the parts become worn it is found necessary to adjust the length of the push rod so as to properly actuate the valves. This has enerally been provided for by threading into the upper end of the body portion of the push rod a common screw bolt, which oftentimes becomes loosened and causes unintentional opening of the valves and consequently improper operation of the engine.

It is one of the objects of my invention to provide the proper length to the push rod by embodying therein a self-locking screw bolt, which when once positioned will remain so until it is found necessary to make adjustment due to wearing of parts.

It further has for its object the provision of a. divided screw bolt provided with means for retaining the threads of the parts of said screw bolt out of continuous trend, said means yielding to pressure to enablethe threads of the two parts of the bolt to be brought into perfect alinement for threading the bolt into the body of the push rod.-

VVith these and other objects in view, the invention consists in the novel features of construction and in the arrangement and combination of parts to be hereinafter described and particularly pointed out in the subjoined claims.

In the drawings,Figure 1 is a side elevation of an internal combustion engine partly broken away to show the operative arrangement of my improved push rod relative to the valves of the engine. Fig. 2 is an enlarged vertical section taken on line 22, Fig. 1. Fig. 3 is a sectional elevation showing. the screw bolt in elevation and the upper end of the body of the push rod into which it IS threaded, in section; the upper part of the screw bolt being shown out of threaded engagement with the body of the push rod. Fig. 4 is a similar view showing the screw bolt in its position of use. Fi 5 1s a section taken on line 5-5, Fig. 3. ig. 6 1s a cross section taken on line 66, Flg. 4.

Like numerals of reference refer to like parts throughout the several figures.

The reference numeral 10 designates a gasolene engine having the usual valve chest 11 in which the valves 12 are operatively held, said valves being closed by the usual springs 13 which surround the stems 14 extending from said valve chest. 15 designates the engine cam shaft hav- 1ng the usual cams 16 thereon which are adapted to actuate the push rods 17 which are slidable in suitable guides 18 formed on the engine casing, or otherwise arranged.

My improved push rod comprises a body portion 19 having an axial bore 20 threaded at its upper portion and in this threaded upper portion my improved screw bolt 21 is adapted to be inserted to any adjusted position. Said screw bolt is self-locking within the body portion 19 and comprises two divided parts 22, 23, the upper part 22, which may be termed the main part, being externally threaded, as at 24, and having at its upper end a hexagonal or other head 25 permitting the use of a wrench or other tool for adjusting the bolt. At its lower end said upper or main part has formed thereon a flattened central portion or tenon 26, from the lower end of which extends a pin or stem 97, said flattened portion or tenon having its side edges 28 madeconvex to conform to the threaded portion of said upper part, and these convex edges are threaded to match the pitch of the threads of said threaded portion. I

The part 23, which may be termed the lower or looking part, is provided with a cross groove or mortise 29 in which the flat central portion or tenon of the main part is adapted to fit. Said part 23 is also provided with an axial opening 30 extending from said cross groove or mortiseto the lower face, through which the pin or stem 27 is passed. Surrounding said pin or stem Patented Nov. 23, 1915. p

is a spiral spring 31 which bears at its upper end against the underside of lower or locking part 23 and at its lower end against a washer 32 which is held to said pin or stem by upsetting the end of the latter, as at. 33. This spring presses the lower or locking part 23 upwardly with the bottom of the cross groove or mortise of said lower or locking part in, contact with the lower end of the central flattened portion or tenor of the upper or main part, and when in this position the threads of the lower or looking part are out of alinement with the threads at the concaved edges of saidflattened portion or tenon.

When inserting the locking screw bolt into the body of the push rod, the threads on the lower or looking part of the screw bolt will enter without ofi'ering any resistance, but when the bolt is threaded into said body sufliciently to bring the threaded flattened portion or tenon ofthe upper or main part in position for entrance into the body of the push rod, it will be necessary to draw upwardly on said upper or main part to slightly raise the same against the action of the spring 31, which brings the threads on the concaved edges of said flattened portion or tenon in alinement with the threads on said lower or locking part, thus permitting the screw bolt to be threaded into the body of the push rod to the desired extent. The'spring 31, however, offers considerable resistance to the insertion of the upper or main part of the screw bolt into the body of the push rod, which resistance tends to crowd the upper bevel faces of the threads of said lower or looking part against the lower faces of the threads in the body portion of the push rod, thus retaining the screw bolt in any adjusted position, due to the fact that the resistance is sufficient to prevent unscrewing of the bolt, except by a turning action of the same.

While my invention is particularly designed for push rods of internal combustion engines, it may nevertheless be adapted for use for various purposes where screw bolts are employed for fastening one part to another, and changes in details of construction may also be resorted to without departing from my invention or sacrificing any of the advantages thereof.

Having thus described my invention, what I claim is,

1. A push rod for engines, comprising a body portion having an axial threaded bore and a screw bolt threaded into said body portion comprising two co-axial parts provided with means to cause it to lock itself into said body portion.

2.- A push rod for engines, comprising a body portion having an axial threaded bore extending inwardly from its upper end, and a screw bolt threaded into said bore and comprising two co-axial externally-threaded parts, the threads of one part being normally out of alinement with those of the other, and yielding means to permit movement of one of said parts to bring the threads of both parts into alinement.

3. A push rod for engines, comprising a body portion having an axial threaded bore and a screw bolt adjustably threaded within said bore and comprising an externallythreaded main part and a similarly threaded co-axial secondary part, said parts having their threads normally out of alinement and having means to prevent rotation of one independent of the other, and means yieldable to force, in the direction of the axis of said screw bolt, so as to permit one part to move on the other and bring the threads of both parts into alinement.

4. A push rod for engines, comprising a body portion having an axial threaded bore and a divided bolt having co-axial parts threaded into said bore, and means for applying force to one part of said bolt so as to cause the threads thereof to bind against the threads of said bore.

5. A push rod for engines, comprising a body portion having an axial threaded bore, a screw bolt threaded into said bore and comprising a main part provided with an axial stem, and a secondary part through which said stem is passed, said main and secondary parts being externally threaded and having co-acting means to compel one to turn with the other, the threads of the secondary part being normally out of aline ment with the threads of the main part,

and a spring surrounding said stem and bearing against the lower or inner end of said secondary part and being adapted to yield when moving the main and secondary parts relatively.

6. A push rod for engines, comprising a body portion having a threaded bore and a screw bolt threaded into said bore and comprising a main part having a head at one end and a tenon at its other end, said main part having also an axial stem extending from said tenon, a secondary part having a mortise to receive said tenon and an axial opening through which said stem is passed, a spring surrounding said stem and bearing against the lower or inner end of said secondary part, and means at the free end of said stem to retain said spring thereon.

7. A screw bolt comprising a main externally-threaded part having a head at its upper end, a flattened portion at its lower end and a stem extending from the lower edge of said flattened portion, an externallythreaded secondary part having a cross groove to receive said flattened portion and an axial opening through which said stem is passed, and a spiral spring surrounding said stem and held thereon to bear against memoe the lower end of said secondary part,-the

threads of said secondary. and mam par being held normally out of alinement by said spring andsaid spring being adapted. 5 to yield under force to permit of bringing the threads of said main and secondary parts into alinement.

v Iii testimony wheredf I amy signature ts in presence of two witnesses 1 JOEL W. NELSON.

Witnesses: EMIL NEUHART,

EDA M. SCHWEIGER.

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