US1820890A

US1820890A - Valve actuating mechanism

Info

Publication number: US1820890A
Application number: US363131A
Authority: US
Inventors: William R Spiller
Original assignee: White Motor Co
Current assignee: White Motor Co
Priority date: 1929-05-15
Filing date: 1929-05-15
Publication date: 1931-08-25
Anticipated expiration: 1948-08-25

Description

Aug. 25, 1931.

W. R. SPILLER VALVE ACTUATING MECHANISM Filed May lS. 1929 2 Sheets-Shee l W E I hIg/FEIf/TOR.

Aug. 25, 1931. w, g SHLLER 1,820,890

VALVE ACTUATING MECHANISM Filed May 15. 1929 2 Sheets-Shee 2.

\/ 27 INVENTOR. MP

Patented Aug, 25 1931 mural) STATES PATENT" OFFICE WILLIAM R/SPILLER, OF CLEVELAND. OHIO, ASSIGNOR TO THE WHITE MOTOR COMPANY,YOF CLEVELAND, OHIO, A CORPORATION OF OHIO VALVE Ac'ruarme MECHANISM Application filed May 15, 1929. Serial No. 363,131.

This invention relates to valve actuating mechanism and is particularly adapted to the operation of valves such as are used in internal combustion motors.

' An object of the invention is to provide a valve mechanism which will automatically,

adjust itself.

Another object is to provide an automatically adjusting valve mechanism which will my compensate for expansion and contraction of its parts and of the associated parts of the motor.

Other objects will hereinafter appear.

The invention will be better understood from the description of one practical embodiment thereof illustrated in the accompanying drawings in which;

. Figure l is a fragmentary transverse sectional view of a motor of the valve-in-he'ad 2a type, having valve operating mechanism embodying the invention;

Figure 2 is an enlarged fragmentary trans-' verse sectional view of the valve tappet and cam shaft of Figure 1; showing the parts in the position they occupy when the valve is closed; i V

Figure 3 is alongitudin-al sectional view of the parts of Figure 2 taken on.line'IIIIII thereof but showing the parts in thepositions they assume when the valve is opened or unseated; I

Figure 4 is a sectional view of parts of Figure 2 taken'on line IV-IV; and

' Figure 5 is a sectional view taken on the line V V of Figure 3.

The motor shown comprises a crank case 1' within which is journaled a crank shaft to be rotated by connecting rods 2, carrying at their upper ends pistons 3 which reciprocate in c linders 4, formed within a cylinder block 5. The upper end ofthe cylinder block I is closed by cylinder head 6, provided with valves 7, each having a stem 8 by which it may be actuated. The valves are maintained I closed by springs 9 surrounding stems 8.

A rocker arm 10 bears, through closure 11, .upon the upper end of the valve stem, the rocker being pivoted at 13 on the cylinder head. A push rod 14 is arranged to raise the opposite end of the rocker, and is actuated from cam shaft 15, journaled within the crank case,-by means of a cam 16.

Between the cam 16 and the push rod 1 1 is located a tappet mechanism so designed that it will automatically adjust itself to compensate for expansion or contraction of the valve mechanism or associated parts of the motor, thereby insuring proper operation of the valve at all times.

This tappet operates in a guide 17 having 0 a generally cylindrical outer surface provided with a flange 18 which seats upon the upper surface of the crank case and is retained in position by a-bolt threaded into the crank case and extending through notch 19.

The interior of the guide is cylindrical at 20 and 21 providing bearing faces for the tappet to absorb the side thrust imposed upon it by the cam, and intermediate these faces are formed key-way like

grooves

22 and 23 10 extending longitudinally Within the guide. The lower portion of the tappet consists of a cylindrical trunk 24 which bears upon the

surfaces

20 and 21 and is rotatably held therein, this trunk being provided at its 15 lower end with a head 25, engaged by the cam, the cam guide being so arranged that the cam engagessaid head only at one side of its center, as most clearly shown in Figure 3. A central bore 26 extends into trunk 00 24 from its upper end and into this bore is threaded ascrew 27, the thread being of small pitch. The screw is rigidly attached to a block 28 which block is slidably carried in

ways

22 and 23 of the guide and by them prevented from rotation, as by the screw being threaded into block 28 and clamped by a lock nut 29.

' The'upper surface of the block 28 is provided with a bearing 30 for the end of the '0 push rod 14. The counter-bore 31 is provided in the upper surface of trunk 24 in which a spiral spring 32is carried, one end of'the spring being attached to the screw and the other end to the trunk, as shown in Figure.5.

The operation of the tappet is as follows: The head 25 rests upon the cam 16 and is constantly rotated within the guide by the rotation of the cam as long as any substantial pressure exists between the parts.

While the cam raises and lowers head 25., the

trunk 24 rotates upon the screw in the manner of a nut, the thread being so pitched that this rotation causes the screw to enter the bore 26 as the tappet rises and lowers and the valve is opened and closed, the rotation of course winding up the spring 32. Due to this shortening of the distance between the block 28 and member 24, when the tappet has moved down the opposite side of the cam, the head 25 will be s need from cam as shown in dotted lines in igure 2. The ten sion of the spring 29 will now rotate the member 24 in a direction to again extend it until the head contacts the cam, in this manner taking up all slack of the tappet mechanism during the part of each-revolution of the cam shaft that the valve remains seated. If, due to the weight of the parts, the head does not remain above the cam as shown, the pressure and consequently the friction between the head and cam will beso slight that the spring will be able to effect the extension of the tappet as above described.

While I have described the illustrated embodiment of my invention in some particularity, obviously many others will readily occur to those skilled in the art, and I do not, therefore, limit myself to the precise details shown and described, but claim as my invention all variations, modifications and embodiments thereof coming within the scope of the appended claims.

1. Valve tappet comprising two blocks one of which bears upon and is rotated by an actuating cam, means for maintaining the other block against rotation, a threaded .pressure transmitting member threaded into one of said blocks and carried by the other and adapted to be translated axially relative the first mentioned block by the relative rotation of the blocks, and a spring for rotating said member relative the first mentioned block in the direction opposite to that in which it is rotated by the rotation of the blocks.

2. Valve actuating mechanism comprising 'a guide having cylindrical bearing surfaces and key-way like bearing surfaces therein, two blocks slidable axially through the guide, one being rotatably held in the first mentioned bearing surfaces and the other being non-rotatably held in the second mentioned bearing surfaces, a screw threaded into one of said blocks and attached to the other, and a spring connecting screw to the block into which it is threaded. a 3. Valve actuating mechanism comprising a'guide having cylindrical bearing surfaces and key-way like bearing surfaces therein, two blocks slidable axially through the guide, one being rotatably held in the first men tioned bearing surfaces and theother being non-rotatably held in the second mentioned bearing surfaces,.a screw threaded into one of said blocks and attached to the other,

' and a torsion spring interposed between said blocks.

4. Valve actuating mechanism comprising a guide having cylindrical bearing surfaces and key-way like bearing surfaces therein, two blocks slidable axially through the guide, one being rotatably held in the first mentioned bearing surfaces and the other being non-rotatably held in the second mentioned bearing surfaces, a screw threaded into one of said blocks and attached to the other, and a spring connecting said screw to the block into which it is threaded, said rotatable block in the first mentioned block, a screw threaded therein and carried by said second mentioned block, and a spring connected to'said screw and to said first mentioned block.

6. Valve actuating mechanism comprising a guide having two opposed cylindrical bearing surfaces and intermediate bearing faces outside the cylinder of the first mentioned surfaces, a cylindrical block slidable and rotatable in said first mentioned bearing sur- I,

faces and having a circular head at its lower end, a block slidable in said second mentioned surfaces and by them maintained against rotation, a centrally threaded bore in vthe first mentioned block, a screw threaded therein and attached to said second mentioned block, and a spring connected to said screw and to said first mentioned block, the spring surrounding said screw and received within a counterbore in the upper end of first mentioned block.

- 7. Valveactuating mechanism comprising a guide extending through the crank case of a motor, a cam shaft below said guide and having a cam positioned to one side of the center thereof, a flange on said guide seated upon the crank case and held thereagainst and against turning by a single screw, two sets of bearing surfaces within said guide one set being cylindrical and the other set lyingoutside the cylinder of said first men'- tioned set, a block having a cylindrical por-. tion received slidably and rotatably within said first mentioned bearing surfaces and having a head at its lower end resting upon the cam, a screw threaded into the upper end of said block, a spiral spring surrounding said screw and having one end attached thereto and its other end attached to the block, .a second block resting upon and attached to neaaeeo block.

' 8 A valve tappet comprising two blocks one of which bears upon and is rotated-by an actuating cam, means for maintaining the other block against rotation, a threaded pressure transmitting member threaded into one of said blocks and carried by the other and adapted to be translated axially relative the first mentioned block by the relative rotation of the blocks, and a spring for rotatin said blocks relatively in the direction opposite that in which they are rotated by the cam.

9. In an internal combustion motor, a cam shaft, a valve controlling communication with the interior of a cylinder of the motor, a tappet interposed between the cam shaft and valve to transmit pressure for operating the valve, threaded rotative means arranged to shorten said tappet during the part of the cycle in which the .valve is open and to extend the tappet during the part of the cycle in which the valve is seated.

10. In an internal combustion motor,a cam shaft, a valve controlling communication with the interior of a cylinder of the motor,

a tappet-interposed between a cam on the cam shaft of the valve and consisting of two parts, one of which has a circular head bearing upon the cam at one side of its center and arranged to be ro ated thereby, means actuated by said rotation to shorten the distance between said parts of the ta pet during/that part oft-he cycle in which tlie valve is open, and resilient means for extending said parts during the part of the cycle in which the valve is seated.

11. A valve ac'uating mechanism compris ing. a two-part tappet,-the parts of which are longitudinallyrelatively movable, means for decreasing the distance between the parts while the valve is opened, and means for in creasing thedistance between the parts while the valve is seated.

12 A valve actuating mechanism compris- 'ingva tappet having two longitudinally movparts and movable longitudinally with rementioned means during the period when the valve is seated.

14. In an internal combustion motor having a cam shaft, a cylinder, and a valve controlling communication with the interior of the cylinder, valve operating means between the valve and cam shaft, comprising two longitudinally relative movable parts, means for decreasing the distance betweenv the parts while the valve is open, and means for increasing the distance between the parts while the valve is seated.

15. In an internal combustion motor hav= ing a camshaft, a cylinder, and a valve controlling communication with theinterior of the cylinder, valve operating means comprising two longitudinally movable parts, means for rotating one of said parts relative the other, a pressure transmitting member inter osed between said parts and movable long1tudinally in respect to one of them by the relative rotation of the parts, and resilient means for moving said member in the opposite direction relative said part after said motion.

16. In an internal combustion motor having a cam shaft, a cylinder, and a valve controlling communication with said cylinder,

valve actuating mechanism com rising two parts which are relatively mova le simultaneously. .both longitudinally and angularly, means for rotating one ofsaid parts relative the other in one direction to move it longitudinally relative the other, and resilient means for rotating the parts relative each other in the other direction.

17. In an internal combustion motor having a cam shaft, a cylinder, and a valve-controlling communication with the interior of the cylinder, valve operating means-between the valve and cam shaft-comprising two relatively rotatable parts, meas for rotating one of said pa'rts relative the other in one direction operative while fthe'valve is open, and means for rotating said part relative the other in the opposite direction operative while i the valve is closed.

In testimony whereof I hereunto afiix my signature this 23rd day-of April, 1929.

WILLIAM R. SPILLEB.

tive said part after said motion.

- '13. In an internal combustion motor, a cam shaft, a valve controlling communication to the interior of. a cylinder of the motor, valve operating means interposed between the cam shaft. and valve to transmit pressure for op-" crating the valve, means decreasing the.

amount of opening of the valve while the same is open, and means returning said last