US1984198A - Valve operating device - Google Patents

Description

Dec. 11, 1934. H. NOTTER 1,984,198

VALVE OPERATING DEVICE Filed Dec. 5, 1930 l'iimmm E iiii iiil Patented Dec. 11, 1934 UNITED STATES *P TENroFFicE VALVE OPERATING DEVICE Harry L. Nutter, Chicago, Ill. Application December 5, 1930, Serial No. 500,268

2 Claims. (01. 123-40 This invention relates to means particularly intended for reducing or eliminating the noise of valve operating mechanism and to increase the efiiciency of the engine by permitting more satisfactory operation of the valves.

The objects of the invention will be understood from the above statement of the nature of the invention and are to improve the construction of valve operating devices; to provide means for preventing tapping or noise incident to the operation of the valves of an internal combustion engine; to provide a valve rocker with improved means for contacting and actuating the valve; to provide a rotatable and yielding contact or connection between the valve stem and the means for actuating the same; and to provide such other novel features and improvements in construction as will appear more fully herein after.

I have illustrated my invention in the accompanying drawing, showing a preferred form of the same in which Fig. 1 is a side view of a valve rocker and coacting-parts;

Figure 2 is a plan view of the same;

Figure 3 is a sectional detail illustrating the position of the parts when the valve is opened;

Figure 4 is a sectional detail illustrating the movement of the contact roller or bushing; and

Figure 5 is a cross sectional view taken on the line 5-5 of Figure 2.

It is well-known that steel or other metals expand when heated and in the usual type of internal combustion engine, particularly those having. over-head valves, the expansion of the valve tappet, push rod and valve stem necessitates that a clearance sufficient to absorb this expansion and permit the correct seating of the valves, should exist between the rocker arm and the valve stem. A clearance of at least one onehundredth of an inch is usually left between the rocker arm and the end of the valve rod to allow for such expansion and in some engines a still greater clearance should be left for proper operation. On account of this clearance, tapping or noises are apt to be made by the rocker arms, particularly when the engine is cold. Such tapping or noise is apt to be considered objectionable and frequently the clearance is reduced toan improper amount so that the valves may be held from their seats after the engine becomes warm. In order to permit all of the clearance necessary or desirable and to eliminate any noise of the rocker arms to the fullest extent I provide the arrangement shown in this drawing.

The push rod 6 cooperates with the adjusting screw 7 which is mounted in the valve rocker 8 in the usualmanner. The valve rocker rocks or oscillates on a rocker shaft 9 which is mounted on the engine in any desirable or well-known manner. Instead of the usual valve rocker having an arm with a flat face for engagement with the valve stem 10, I provide a rocker having one arm 11 provided with a bearing, 12 at its outer end for receiving a movable contact member or roller 13 which engages with the end of the valve stem 10. While the hole or recess 14 for the movable member 13 may be of any desired shape, I prefer to make the same in the form of an oval with the center of the upper part somewhat nearer the vertical plane through the center of the, valve rocker shaft to increase the rolling movement between the roller and the bearing and to tend to prevent any tapping or clicking between these parts. e

The contact roller or cylinder 13 is pressed downwardly or towards the valve stem by any suitable spring or yielding means such as the spring 15 shown. This spring bears against a pin or fulcrum 16 which projects through a lug or car 17 on the arm 11. The rear end of the spring bears against the valve rocker and the forward end is bifurcated so that it takes over or straddles the lug 17 which holds it in position. The forward ends of the bifurcated por tion of the spring are provided with short pins 18 which projectdownwardly through holes 19 in the bearing 12 and engage with peripheral grooves or slots 20 in the surface of the roller 13.- By means of this arrangement, the spring not only presses the roller downwardly but the pins or projections 18 also serve to hold the roller against longitudinal movement. As shown particularly in Figures 3 and 5 the bearing 12 is cut away at 21 so that the valve stem 10 may engage with the roller 13.

In this particular arrangement it will be seen that the necessary clearance is provided between the roller or contact member 13 and the upper surface of the hole or recessin which it has its bearing and such clearance may be provided in accordance with the characteristics of, different engines. It Will be, of course, understood that the tension of the spring 15 is much less than that of the valve springs 22.

My improved valve rocker is preferably adjusted so that the contact member 13 substantially floats between the pins or projections 18 and the upper end of the valve stem 10 although I remaining in contact with the side of the bearing. In other words, the screw 7 is preferably adjusted so that when the engine is cold, the roller will slightly clear the lower portion of the bearing. In the operation of the device, the first movement of the rocker arm causes the bearing for the contact member or roller 13 to move downwardly or toward the roller which is held by the valve stem. The pins or projections 18 preferably engage the roller at points slightly on the inner side of the vertical plane through the valve stem so that the tendency is for the bearing to move down along the outer surface of the roller, or the apparent movement is that the roller rolls against the outer surface of the bearing until it reaches its uppermost position, at which point it makes contact with the bearing and the further movement of the rocker causes the valve stem to be forced downwardly. This continuous contact between the contact member 13 and its bearing and the tension of the spring 15 serves to take up the lost motion or clearance with practically no noise and also serves to. permit a sufilcient clearance, or even an excessive clearance to be provided so that there will be no possibility of the valves being held open. Furthermore, the tension of the spring 15 also serves to hold the lower end of the adjusting screw against the push rod so as to prevent any opportunity for noise at this point, and in fact keeps all of the valve operating parts under sufficient tension to prevent any tapping or rattling thereof.

It will also be noted that on account of the arcuate movement of the roller as it is swung by the rocker arm there will be a slight lateral or relative horizontal movement between the same and the valve rod which will tend to rotate the roller and thus distribute any wear on the same throughout the circumference thereof.

It will further be seen that the tension on the various valve operating parts due to the spring 15, not only prevents rattling or noise between such parts but holds the contact member or roller 13 constantly in engagement with the valve stem. When the bearing moves downwardly, it is gradually brought into engagement with the roller so that when the final clearance is taken up and the bearing presses downwardly on the roller to open the valve, there will be little or no tendency toward making any clicking or tapping sound.

My improved device is intended to be utilized for various kinds or makes of engines and as there is considerable variation in the construction of the same, changes may be necessary in the details of construction or arrangement of the parts of my improved device to adapt it to different engines and therefore I do not wish to be limited to the particular construction or arrangement herein shown and described except as specified in the following claims in which I claim:

1. In an apparatus of the character set forth,

the combination of a push rod, a valve rocker,

an adjusting screw connecting one arm of the valve rocker and the push rod, a bearing at the outer end of the other rocker arm having an oval shaped opening therein, the largest dimension of which is at an angle to the vertical, a roller mounted in said bearing and having annular grooves therein, a valve stem projecting through the side of the bearing and engaging with the roller, a lug on said rocker, a bifurcated spring having one end engaging with the rocker, a fulcrum passing through the lug and engaging with the bifurcated portions of the spring, and pins on the ends of the bifurcated portion of the spring projecting through holes in the side of the bearing and engaging with the annular grooves in said roller.

2. A valve rocker of the character set forth having a transverse bearing at one end thereof with an opening through the lower portion of the bearing, a roller having annular grooves mounted in said bearing, the hole in the bearing being larger than the roller to permit predetermined clearance therebetween, pins projecting through the bearing and engaging with said grooves and a spring mounted on said valve rocker and tending to press the pins against the roller, substantially as described.

HARRY L. NOTTER.

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