US1551181A - James r - Google Patents

Description

Aug. 25, 1925. r J. R. TULLY PUSH ROD SILENCING DEVICE FOR INTERNAL COMBUSTION MOTORS Filed May 28-. 1921 James R.

Patented Aug. 25, 1925.

UNITEDSTATES 1,551,181 PATENT OFFICE} AMES 'R. TULLY, or HUNTINGDON, oUEBEdcANAnA.

PUSH-ROD SILENCING DEVICE FOR INTERNAL-COMBUSTION MOTORS;

Application filed May 28,

tion is to provide a simple, durable, ineX- pensive and eflicient means for eliminating the clicking which is inherent to the push rods of. internal combustion motors.

A further objectis to improve the lubrication of the tap-pets.

A still further object is to eliminate Wear of the push rods and tappets where they meet.

Internal combustion engines of the;four cycle type, as at present generally used for automobile and marine work, all employ loose push rods between the tappets and valve stems or rockers, according to-whether the engine is valve in the cylinder or valve in the head type. There is necessarily a slight slackness orclearance between these push rods and the tappets and valves or rockers to permit the valves to close tightly, especially when the engine is well heated up and the valvestems, push rods and tappets have expanded. This necessary clearance causes a very noticeable clicking as the parts come together andwhen the engine is running at high speed the clickin develops into a considerable and disagreeabe sound. Furthermore, each click indicates a not inconsiderable hammer blow and such blows frequently repeated wear the push rods, tappets and valve stems or rockers so that the clearance is increased and the condition aggravated. This is especially so when the engine is operating in a dusty atmosphere from which grit settles on the parts and works between the abutting faces of the parts.

According to the present invention, thls clicking noise is entirely eliminated and wear due to grit done away with by providing a dust-tight, oil-filled casing around the ends of the push rods. The push rods are usually disposed vertically with the tappets beneath them and in most cases it will suifice 1921. Serial. No. 473,388.

to enclose the lower ends of the push rods.

and upper ends of the tappets.

In the drawings which illustrate the invention;-- s

Fig. 1 is a vertical sectional View of a tappet guide formed according to the invention. Fig. 2 is a vertical sectional View illustrating the invention applied to an existing tappet guide.

Referring more particularly to the drawings, 11 designates a tappet guide, 12 a tappet and 13 a push rod of any design.

According to this invention a casing 14 is provided above the guide 11, either integral therewith as shown in Figure 1 or separate therefrom as shown in Figure 2. This eas ing surrounds the lower portion of the push" rod in spaced relation theretoand serves to hold a heavy oil, such as is generally, known as cylinder oil, indicated at 15. To hold the oil against escape at the top of the casing and also to exclude dust, a cap 16. is attached to the top of the casing, preferably by screw threads. The cappreferably contains a felt-washer 17 which it holds down against the top of the casing, thus keeping i the washer in place. The felt washer may be supported from below by a ri id washer 18 resting directly on the casing. Ireferably the push rod is a tight fit in the felt washer so that oil will notwork up on the rod nor dust work down. The felt washer is kept .wet with oil from within the casing adhering tothe push rod and is thus self-lubricating. The cap and metal washer 18 have apertures 19 for the passage of the push rod, considerably largerthanthe rod, so that the rod will not touch them. In this way the alignment of the tappet rod and valve stem or rocker isnot interfered with, the felt washer being suflicientlyyielding to permit any lateral movement of the rod.

In an engine of the valve in the head type where rockers are used, the push rods are generally connected to the rockers so that the push rods hang from the rockers and the clearance is formed between the push rod and tappets. For an engine of this type the device as thus far described is complete. In an engine of the T-head or ity the push rods will rest on the tappets up and as it is-not convenientto provide casings as described about the lower ends of valve stems it. is necessary to transfer the.

clearance from the upper to the lower ends of the push rods. coinplished by providing a light spring 20 in compression bet-Ween the'cap 16 and a collar 21 mounted the push rod. This spring need be-Onlys'trong enough to hold the push rod against the valve stem; and maintain the "clearance a-tthe lower end of therod; I 1

jIn operation the device isas follows:- The heavy oil in the casingforms a cushion between the tappet and push rods The oil being heavy will not easilysqueeze out-from between the parts, especi'a-lly Where the push rod loosely enters the tappet or vice versa. The "oil compels thev parts to come together gently and thus the clickingsound is entirely eliminated; The felt Washer keeps the oil from escaping from the'casi ngor "creeping '-up"on the push rod and also 'eX- chides dust and grit thus reducing thewear of the parts. The oil -ingthe casingserves also to lubricate the tappet'andif the oil is "of sufiicient bodyv it Will escape-only very slowly between the, tappet and guide and until nearly or completely exhausted is available'for ci'i-shioning purposes, Escape "ofo'il "through this channel is no disadvantage as jitruns into the engine base. 'Prefera-bly the casing should he "nearly full "of oil when the tappetis in its uppermost position, as indicated in Figure 1, therefore care should be'ta'ken when filling the easings to note the'po'sition of the tappets and gauge the properoil level accordingly.

As, i ndicatedvfin the drawings the invention is applicable either -by providing new 'tappet guides 'orfby attaching the "oil casing to an existing guide. While it is-o'b'vious'ly preferable toflocate fdevi'ce the lower This may be 'easily 'ac- 'and push rod but applies equally to all.

.be necessary to accommodate it to engines the tappe'tand push rod and adapted to ends of push rods, it will be understood that it may be located at the upper ends of the push rods or applied to similar mechanisms W- i-thout departing from the spirit of the invention. It Will also be understood that the invention is not limited to any particular style or design of tappet guide, tappet It Will furthermore be understood that the form of casing shown and described is merely for illustration and that the invention-is not limited thereto but embraces all such special forms of construction as may of different designs.

Having thus described my invention, What I clain'1"isj; I 7

1. The combination with a tappet guide, tappet and push rod, of 'a casing-carried' by the gu-ide and surrounding adjacent ends of the t'a-ppet and push rod and adapted to -'con tai n oil, ac'over for the casing in spaced relation to "the push rod and a resilient washer carried by-the cover in engagement with the push re- 2. Thecom'bination with a tap pet guide, ta-ppe't and push red, of a casing 'carried by the guide and surrounding; adjacent ends of contain oil, a cover for the easing, arigi d Washer Within the cover engaging the' 'end of the casing, and a resilient Washer'between the cover and rigid WilShBlK 3; In combination, a tappe't, a *p'ushrod to engaging the tappet, one of said members being pocke'tedto loosely receive the other and, constitute a "dash pot, and a reservoir for a cushion liquid having communication at substantiallyits bottom with the open *8 *endof said clash pot thereby t'o supply liquid w the dash pctwhile any re'mains in' the reservoir.

' In-witnes's whereof,- I "have hereunto :set

my hand. 3

7 JAMES in TULLY.

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