US2448989A - Engine rocker arm - Google Patents

Description

Sept. 7, 1948. J. M. LEAKE 2,448,989

ENGINE ROCKER ARM Filed Feb. 18, 1946 INVENTOR.

Patented Sept. 7, 194a UNITED .STATES PATENT OFFICE mom; 1223 m. Q

James M. Leake, Monroe, Mich.

Application February 18, 1948, Serial No. 648,327

My invention relates to rocker arms and more particularly to the type of rocker arm used to operate the valves of an overhead valvetype of internal combustionengine. Y

The present types of engine rocker arms are made from forgings, castings and stampings. The stamped engine rocker arms are lighter in weight than the forged or cast engine rocker arms. These stamped engine rocker arms are provided with. a fixed contacting bearing. Considerable difilculty is encountered in obtaining proper alignment of the fixed contacting hearing. My novel arrangement combines a light weight stamped arm'member with a self-aligning contacting bearing. f

In the present day high speed engine weight is a very important factor. The engine rocker arm oscillates'when the engine operates. Therefore the heavier the engine rocker arm the greater the inertia and hence the more, power required to operate the engine rocker arms. In airplane engines weight is a very vital factor, and a very appreciable saving in weight is accomplished with the use of my improved-engine rocker arm, since two ormore arms are required for each cylinder. I

'My improved engine rocker arm also provides a self-aligning feature which saves time, expense and scrap in the manufacturing process and at the same time provides greater accuracy in the valve operating mechanism of the internal combustion engine. v

One object of my invention is to provide an engine rocker arm that is light in weight.

Another object of my invention is to provide an engine rocker arm provided with an arm member of a hollow cross sectional construction formed from sheet metal.

Another object of my invention is to providean engine which provides an improved lubrication system.

Another object of my invention is to provide an engine rocker arm with a self-aligning contacting bearing. a 7

Another object ofmy invention is to provide an engine rocker arm that is strong, durable and inexpensive.

With these and other objects in view, my invention consists in the construction, combination and arrangements of the various parts of my improved device as described in the specification, claimed in the claims and illustrated in the accompanying drawing In the drawing:

Figure 1 is a front elevation of my improved engine rocker arm.

Figure 2 is a top plan view of my improved '1 Claims. (01. 14-519) Figure 4 is a sectional view taken along line 4-4 of- Figure 2 with an adjustable contactin bearing.

Figure 5 is an enlarged sectional view taken along line 5-5 of Figure 2.

Figure 6 is a front elevation of the lower member of my improved engine rocker arm.

Figure '7 is a top plan view of the lower member shown in Figure 6. I

Figure 8 is a top plan view of the retaining spring used in my improved engine rocker arm.

Figure 9 is a front elevation of the self-aligning contacting bearing used in my improved engin rocker arm.

Figure 10 is a top plan view of the self-aligning contacting bearing shown in Figure 9.

Referring to the drawing in more detail, in Figure 1, I have shown a stamped or pressed arm member iii. The arm member in is pressed from a flat sheet metal blank which has been out to .a predetermined size and shape. The arm member 10 comprises substantially parallel side walls il--ii spaced a substantial distance apart, and an upper wall l2 integral withvthe side walls ii-H, thus producing an inverted U-shaped cross section. The side wall portions li-l i are joined by end wall portions which are integral with the side walls i l-li and the upper wall i2, thus a continuous wall is provided around the sides and ends of the arm member in.

The sides of one end of the arm member ID are formed into a partial prism portion 13. The opposite end is formed into a concavo-convex portion ii that is substantially hemispherical. A concavo-convex member I 5 is secured in the concave-convex portion I4 ofthe arm member Ill. The inner or concave surface it of the concavoconvex member I5 is a smooth bearing surface hemispherical in shape. 'A self-aligning contacting bearing I1 is provided with a head portion l9 and a stem portion IS. The head portion l9 engages the hemispherical concave bearing surface 18. A lower stamping 20 is secured between the side walls ll of the arm member ID. The lower stamping 20 is U-shaped in cross section through most of its length. The sides 2l-2i of the mem ber 20 are secured to the sides li--li. At one end of the lower stamping the sides provide a partial prismatical socket 23 integral with the lower wall 22., The partial prismatical socket 23 is secured in the partial prism wall portion l3. A nut or internally threaded member 24 is secured in the partial prismatical socket 23.

An adjustable contacting bearing 25 provided with a threaded stem 26 is adjustably secured in' v the internally threaded member 24, and is locked in a predetermined position by the lock nut 21.

A "ring portion 28 is provided at the end of the lower stamping 20. The ring portion 28 is secured in the concave-convex portion ll, adjacent the 3 lower edge of the concavo-convex bearing member 15. The ring portion 23 is preferably recessed to hold the self-aligning contacting bearing retainer member 29.

A hub member 30 extends transversely through apertures in the side walls "-11 and from both sides of the arm member 10. A bushing or hearing 3| is secured in the hub 30. The bearing 3! is adapted to be journaled on a rocker shaft (not shown). A tubular member 32 extends from the hub to the upper wall I 2 and communicates with an aperture 33in the bushing 3| thus providing an oil passageway 34 from the bearing 3! to the upper surface of the wall l2. The oil passageway 34 communicates with the oil channels 35 and 36 to provide oil at both ends of the engine rocker arms.

From the channel 35 oil flows over the partial prism'portion l3 down the sides thereof and onto the lower stamping 20 and finally onto the adjustable contacting bearing 25. The adjustable contacting bearing 25 which usually engages a push rod (not shown) is thus lubricated. Oil flowing down the channel 38, passes through the aperture 31 to the felt oil control member 38. From the felt oil control member 38 oil is provided to the surface l6 and the head 19 of the self-aligning contacting bearing H.

The arm member ID, the lower stamping 20, the internally threaded member 24, the concavoconvex member IS, the hub 30 and. the tube 32 are preferably brazed or welded into a substantially one piece member. In operation pressure is exerted upwardly on the contacting bearings l1 and 25, while the bushing or bearing 3i bears against the engine rocker arm shaft (not shown). The upward force applied to the adjustable contacting bearing 25 is transmitted to the nut or threaded member 24, which is brazed in the socket 23 and also bears against the upper wall l2. Hence the upward force exerted on the nut 24 is adequately and proportionally distributed to the arm member l and to the lower stamping 20. The upward force exerted onv the self-aligning contacting hearing I! by the valve stem 39 is transmitted to the concavo-convex member 15 and then to the concavo-convex portion I4 of the arm member III. The upward force tends to push both the threaded member 24 and the concavo-convex member I5 against the upper surface of the arm member l0. Hence it is not necessary for the brazed'joint to take the entire stress. In case the brazed joint fails the engine rocker will continue to operate.

In assembling the engine rocker arm the head portion I9 of the self-aligning contacting bearing I1 is placed in the concave-convex member I5. The spring member 29 is then snapped into place so that the self-aligning contacting bearing I! cannot drop out of the concavo-convex member I 5. Whenever the self-aligning contacting bearing I! has to be replaced the spring member 29 must be removed in order to remove the worn out part and insert a new self-aligning contacting bearing. The spring member 29 is then replaced.

If the valve stem 39 is not in proper alignment with the self-aligning contacting bearing H the head 19 will turn in the concavo-convex bearing I I 5 so that the stem l8 will seat flatly on the valve stem 39. In this way variations in angularity, alignment and tolerances due to slight variations in production are compensated for by my improved engine rocker arm.

, From the above description it will be apparent tion.

While I have described the details of one form of my invention, I do not wish to be limited to the particular forms shown and described as it will be apparent that modifications therein may be made without departing from the scope of my invention as set forth in the appended claims.

Having thus described my invention what I claim is:

1. An engine rocker arm comprising a central bearing support, an arm member extending in substantially opposite directions therefrom, said arm member comprising an upper inverted U- shaped stamping and a lower U-shaped stamping said upper and lower stampings being telescoped and fused together to form a box section construction, an internally threaded member secured between the side walls'of said lower U shaped stamping at one end thereof, a contacting bearing adjustably secured in said internally threaded member, a concave portion provided in the under side at one end of said upper inverted U-shaped member, a concavo-convex bearing membersecured in said concave portion, and a self-aligning contacting bearing swivelably secured in said concavo-convex bearing member.

2. An engine rocker arm comprising a central bearing support, an arm member extending in substantially opposite directions therefrom, said arm member comprising an upper inverted U- shaped stamping and a lower U-shaped stamping said ,upper and lower stampings beingitelescoped and fused together to form a box section construction, an internally threaded member secured between the side walls of said lower U-shaped stamping at one end thereof, a contacting bearing adjustably secured in said internally threaded member, a concave portion provided in the under side atone end of said upper inverted U-shaped member, a concave-convex bearing member secured in said concave portion, and a self-aligning. contacting bearing provided with a partial spherical head portion adapted to swivel in said 'concavo-convex bearing member and a means for retaining said partial spherical head portion in said concavo-convex bearing member.

3. An engine rocker arm comprising a central bearing support, an arm member extending in substantially opposite directions therefrom, said arm member comprising an upper inverted U- shaped stamping and a lower U-shaped stamping said upper and lower stampings being telescoped and fused together to form a box section construction, an internally threaded member secured between the side walls of said lower U- shaped stamping at one end thereof, a contacting bearing adjustably secured in said internally threaded member, a concave portion provided in the under side at one end of said upper inverted U-shaped member, a concavo-convex bearing member secured in said concave portion, a selfaligning contacting bearing provided with a partial spherical head portion adapted to swivel in said concavo-convex bearing member, a. ring portion integral with lower U-shaped stamping extending adjacent the lower edges of said concavo-convex bearing member and retaining a resilient member, said resilient member adapted to retain said self-aligning contacting bearing.

4. An engine rocker arm of box construction, comprising an upper stamping of inverted U- shaped cross section, a lower stamping of U- shaped cross section telescoped within said upper stamping and fused thereto, a hub secured transverse to said upper stamping, intermediate its ends, an internally threaded member secured between the side walls of said lower stamping, a contacting'bearing adjustably secured in said internally threaded member, a concave portion at one end of said upper stamping, a concave-convex bearing member secured in said concave portion, and a self-aligning contacting bearing swivelably secured in the concave portion of said concavo-convex member.

5. An engine rocker arm of box construction, comprising an upper stamping of inverted U- shaped cross section, a lower stamping of U- shaped across section telescoped within said upper stamping and fused thereto, a hub secured transverse to said upper stamping, intermediate 1 its ends, an internally threaded member secured between the side walls of said lower stamping, a contacting bearing adjustably secured in said internally threaded member, a concave portion at one end of said upper stamping, a convavo-convex bearing member secured in said concave portion, and a self-aligning contacting bearing provided with a, partial spherical head portion swivelably secured in the concave portion of said concavo-convex member, a ring portion integral with said lower stamping adjacent the lower edge of said concavo-convex member adapted to retain a spring member whereby said self-aligning contacting bearing is removably secured in said concave portion of said concavo-convex memher.

6. An engine rocker arm comprising a hollow arm member, said arm member comprising an upper stamping of inverted U-shaped cross section and a lower stamping of U-shaped cross section telescoped within ,said upper stamping,

v arm member intermediate its ends and a bearing member secured in said hub.

7. An engine rocker arm comprising a hollow arm member, said arm member comprising an upper stamping of inverted U-shaped cross section and a lower stamping of U-shaped crosssection telescoped within said upper stamping, an internally threaded member secured within said arm member at one end thereof, a bearing member provided with a substantially hemispherical concave portion secured at the other end of said arm member, a self-aligning contacting bearing swivelably secured in said hemispherical concave portion, a hub secured transverse to said arm member intermediate its ends and a bearing member adapted to be journaled on a shaft secured in said hub, a tubular member extending from said hub to the upper surface of said arm member and a plurality of oil channels in said upper stamping extending from said tubular member to the proximity of the ends of said arm member.

JAMES M. LEAKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,132,411 Watts Mar. 16, 1915 1,904,770 Skillman Apr. 18, 1933 2,230,520 Wemp Feb. 4, 1941 2,251,143 Loeflier July 29,1941

FOREIGN PATENTS Number Country Date 349,508 Great Britain May 26, 1931

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