US1549636A - Valve mechanism - Google Patents

Description

Aug. 11, 1925. n 1,549,636

W. H. VON HACHT VALVE MECHANISM Filed Nov. 22, 1923 2 Sheets-Sheet l M, .g N QZ 5 ,f'

Aug. 11, 1925. y 1,549,636

W. H. VON HACHT VALVE MEcHANI'sM FiledANov. 22, 1923 2 Shets-Sheet E wa M' ATTORNEYS.'

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Patented Amiga, ll, 1225,

WLLIEAM H. VON HACHT, F V'LEJ', CLIFGRNA.

'vanvn' Mnenan'rsnr.

Application tiled November 22, 1923. Serial No. 676,401.

To all whom 'it may concern.:

Be it known thatl l, WILLIAM l-l. voN HACHT, a citizen of the United States, and a resident of Vallejo, county of Solano, State of California, have invented a new and useful Valve Mechanism, of which the following is a specihcation.

rlhis invention relates to valve mechanisms as used with engines, particularly of the internal combustion type and has to do with the division of such engines known as the overhead valve type.

rllhe principal objects of my invention are to overcome the noisy operation of the overhead valves vby the entire elimination of the usual rocker arms and the usual working clearances now provided, also to provide a simpler construction, an improved oiling arrangement, an easier adjustment for the valve lift, a reduction of weight over the generally adopted construction, and means by which the entire valve operating mechanism may be detached from the engine as a unit, for replacement or repairs.

l attain the objects outlined in theoverhead valve operating mechanism illustrated in the drawings accompanying this specification in which Figure 1 is a side elevation of a portion of a multi-cylinder internal combustion engine, with my valve mecha- Y nism in place; Figure 2 is a vertical cross section of the engine cylinder and valve mechanism along the line 22 of Figure 1; Figure 8 is an enlarged side view of one of the [1 -shaped push rods for actuating the valves; Figure 4 is a plan view of the end of the arm of the rod; Figure 5 is an end view of the cam roller carrying lower end ot the rod; Figure 6 is a vertical cross section similar to Figure 2 but shows a modication in positioning the cam shaft and rod springs which inverts the action of the rod in respect to the functioning of the valves;

Figure 7 shows a modied valve stem connection.

ls will .be seen by reference to Figures 1 ani 2 my valve mechanism contemplates the entire omission of rocker arms, etc.'

` and voperates the' valves by means of l.-

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sha ed push rods (1) slidable up and down in hearings (2) and having an arm (3) projecting at right angles to the sliding portion ofthe rod over the top of the engine n? engaging the stems (3') oflthe valves The engine tiring chamber is indicated at (5),' iston at (6), water circulation space at (7S), and spark plug at (8). Figure 2 shows these parts clearly and also at (9) a separate valve mechanism casing bolted t(o t he side of the engine by bolts or studs This casing (9) may of course be an integral portion of the engine casting (11) but if made separable as indicated it provides for quick removal of the entire valve operating mechanism including the cam shaft, as the l. arms of the push rods are slotted at (12) so that when the casing is unbolted it may be pulled ed of any studs and away from the` valve stemengagement with the slots (12). Ilhe casingA has an upper, lower, and central horizontal wall as indicated, and in the upper and central are threaded or otherwise secured the bearings (2) for the sliding rods rllhe rods each have a cam wheel (13) rotatably supported at their lower ends, preferably in a slot (1t) formed in the lower end and are positioned directly over a revolvable cam shaft (15) having the usual valve trippinc cams formed along it,- as indicated at The cam shat has bearing" in the casing at several places as indicated at (17) and is coupled at some point not shown in the drawing for operation by the engine throughv the Vuspal gear Y A sequence and the rods are returned by l heavy spiral springs (18) expanding between collarsA (19) on therods and the upper bearings l ln the design shown in Figures 1 and 2 the action of the rods is the reverse from the push rods in the rocker arm type of valve motion wherein the cam opens the valves, v'whereas in Figures A1 and 2 the Cam closes the valves, that is, the lifting of the rods lifts the arm (8) and thereby carries the valve stem (3) upward, thus the valves (t), and upon il? of the cams the spring (.18) forces the rods down upon the cams and opens. the valves1 As it would be extremely dicult to insure proper seating of the valves at the highest point of the cams l provide an e lll@ lll@

valve stem and the arm (3) which moves its This is done by threading the rody and screwing thereover a drilled and threaded sleeve having a hexagon head (21) at its outer end and a nut (22) screwed over its lower end, and surrounding the sleeve are two springs (23) and (24), one being above and one below the flattened portion (25) ofthe slotted arm (3) embracing the sleeve. These springs are under compression through means of the nut (22) and balance the arm (3) between them so that the arm in moving carries the valve in both directions, but they aiford a cushion against shock and noise and as against the usual valve clearance and provide for a slight A compression of the upper spring to insure a perfect seating of the valve, as the ad- -justment should be such that the cam lift is slightly in excess of the required amount to seat thevalve.

rlhe adjustment .is secured by screwing the sleeve (20) up or down on the valve stem and locking it by the nut (26). To prevent the stem from turning it is slotted for a screw driver at (27).

To facilitate inspection of the valve mechanism the outer wall plate (28) of the casing is preferably made separable as indicated; either in whole or in part; and in Figure 1 this wall plate has been omitted to reveal the mechanism described and also to show vertical partitions (29) for stif fening the structure and providing means for supporting the cam shaft bearings (17) and casing stud bolts (10). y

The proper lubrication of the parts is effected by maintaining a quantity of oil (30) in the lower part of the casing to submerge the cams and having a pipe (31) leading therefrom to an oil pump (not shown) for pumping it to the upper bearing through the pipe (32) and where itmaintains a level (30') to the overiiow tubes (33) in the casing, flowing through the bearings or oil overflow tubes to the central partition where the level (302) is maintained and the same overflow principle is repeated, thus returning the oil to the lower partof the casing for use over again.

A cover (34) extends over the upper portion of the engine to keep out dust and also to convey the oil vapors to the springs (23) and valve stem (3') to provide the slight lubrication which they require.

Figure 3 shows in enlarged elevation a side view of a push rod detached from the casino` and with its features described bearing the numerals given. The rod is preferably formed out of a single piece of steel tubing with a rounding bendI at (35) and flattened at the valve stem engaging end as indicated.

Figure 4 shows the slot `for engaging the sleeve on the stem, but a round hole may be used instead of the slot in engines where the casing is made integral with the engine, and lateral removal is notcontemplated.

To insure aperfectly round push rod the tube is preferably turned from the point (36) down to the lower end. Figure 5 shows the lower'end of the tubular rod with cam wheel in place. The tube is slotted at (14) and preferably bushed at (37) to afford a proper support for the cam pivot pin (38);

While the mechanism shown and above described is my preferred arrangement, my invention may assume the form shown in Figure 6 wherein the same elements yare shown and numbered with exponents placed on the rearranged members.

In'this arrangementthe cam shaft (15') is placed above the rollers (16) as indicated so asto push the rods down instead of up, and the spring (18 placed at the bottom of the casing to force the rod upward upon being released by the cam.

This results in the cam opening the valves and the spring closing them, whereas in the first arrangement the cam closes the valves and the spring opens them.

While l show the springs (23) and (24) around the valve stem7 in both arrangements, it is apparent that this resiliency could be obtained by several other artifices; one of such might be making the arm (3) itself resilient, or of having the bend (35) of the arm looped or enlarged sufficiently to afford the necessary resiliency, which though important need be very slight in order to insure closing of thevalve, and any such in the end of the arm (3) instead of havinga spring on both sides of it, has a spring on the upper side only to insure resilient closing of the valve but bears directly against the lower of two sleeve nuts (37)-(37) for positive opening of the valve.

I claim:

1. In a mechanism of the character described, a poppet valve having a stem, a cam operated push rod having an arm thereon resiliently engaging the stem, the engagement comprising a sleeve adjustable along the stem embraced by the arm and a spring around the sleeve bearing against the arm.

2. In a mechanism of the character described, a poppet valve having a stem, a

of the 8.11.11 arranged to bear against the armto hold same in floating relation between them.

3. In an engine having a plurality of overhead valves each with a stem, a ypush rod loi each'valve stem, a cam shaft having cams for operating the push rods, a casing entirely supporting the rods and the cam shaft in operative relation, said casing being removably secured to the side of the engine whereby the rods and cam shaft may all be removed-without disturbing their operative mounting. y

4. In an engine having a plurality of overhead valves each With a stem, a push rod for each valve stem, a cam shaft having cams for operating the push rods, a casing entirely supporting the rods and the cam shaft in operative relation, said casing being removably secured to the side of thev engine whereby the rods and cam shaft may all be removed without disturbing their operative mounting, and said rods having each an arm at the upper end extending to its respective valve stem and engaging the same in an open ended slot adapted for lateral withdrawal from the stem in direction of removability of the casing.

5. An overhead valve operating mechanism for an engine embracing a plurality of poppet valves on the engine having stems, slidable push rods having arms engaging the stems, upper and lower bearings for the slidable push rods, a cam shaft for operating the push rods, springs surrounding the push rods for holding the rods to the cams, a reservoir of oil in which the cams are submerged and a similar reservoir at each bearing and conducting means for circulating the oil successively through the reservoirs.

6. In an engine having an overhead valve with a stem, a cam actuated slidably supported push rod therefor comprising a tube having its upper end bent to form a laterally extending arm reaching to the valve stem, and the extreme end of said tube having -its Walls brought together to form a flattened portion and there engaging the stem.

7 In an engine having an overhead valve with a stem, a cam actuated slidably supported push rod therefor having a laterally extending arm at its upper end engaging the stem, the engaging portion of the arm having an open ended slot adapting the arm for lateral withdrawal from the stem.

WILLIAM H. vonl BACI-IT.

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