US789078A - Valve-gear. - Google Patents

Description

PATENTED MAY 2, 1905.

F. W. BOHN.

VALVE GEAR.

APPLIOATION FILED JUNE 20, 1904.

2 SHEETSSHEBT l.

lg egor.

158K956? '6 I (I M UNITE STATES Eatented May 2, 1905.

4 ATENT @rrrce.

FREDERICK IV. BOHN, OF INDEPENDENCE, WISCONSIN, ASSIGNOR OF ONE- HALF TO ALBERT J. BAUTCH, OF INDEPENDENCE, WISCONSIN.

VALVE-GEAR.

SPECIFICATION forming part of Letters Patent No. 789,078, dated May 2, 1905.

Application filed June 20,1904. Serial No. 213,360.

I all whom, it may concern.-

Be it known that I, FREDERICK W. BoHN, a citizen of the United States, residing at Independence, in the county of Trempealeau and State of Wisconsin, have invented a new and useful Valve-Gear, of which the following is a specification.

This invention relates to improvements in steam-engines, and particularly in the construction and arrangement of the mechanism for controlling its speed and direction of rotation.

The principal object of the invention is to provide an improved governor and cut-off in 5 which the valve-operating cam is shifted in accordance with the speed of the engine and is under direct control of a suitable governor, provision being also made for primarily adjusting the point of cut-off and for reversing the engine by means of a manually-operated lever.

A further object of the invention is to provide a novel form of shiftable eccentric in which provision is made for taking up any 2 5 wear which may occur to the parts and, further, to lessen the amount of frictional wear on the eccentric and other movable parts of the engine by providing the same with ballbearings.

A still further object of the invention is to provide in mechanisms of this class for arranging the governor at any desired point on the movable shaft, either near to or at a distance from the eccentric by which it is operated.

A still further object is to provide a novel form of governor which will be effective in both positions of the parts and will serve to move the cut-off cam in a direction governed 4 by the direction of rotation of the engine.

With these and other objects in view, which will more fully hereinafter appear, the invention consists in the novel construction and arrangement of parts hereinafter described,

illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportions, size, and minor details of the structure may be made without departing from the spirit or sacrific- 5 ing any of the advantages of the invention.

In the accompanying drawings, Figure 1 is a plan view of a portion of an engine provided with valve-gearing constructed in accordancewith theinvention. Fig. 2isatransverse sectional elevation of the same on the line 2 2 of Fig. 1. Figs. 3, 4:, 5, 6, 7, and 8 are sectional views on the section-lines bearing the corresponding reference-numerals in Fig. 1. Fig. 9 is a detail perspective view of the eccentric-shifting cam-block detached.

Similar numerals of reference are employed to indicate corresponding parts throughout the several figures of the drawings.

The working parts of the engine are sup- 5 ported on a suitable bed-plate 1, having bearings 2 for the reception of the main shaft 3. The valve-rod 10 of the engine is connected to an eccentric-strap 11. The eccentric-strap is arranged on an eccentric 12, the periphery of 7 which is provided with a groove for the reception of bearing-balls 13, so as to reduce to a very considerable extent the friction which ordinarily exists between the eccentric and its strap. The eccentric is provided with three parallel slots 14, 15, and 16, the slot 14: being of greater width than the others and serving for the passage of the main shaft 3, while the slots 15 and 16 receive hollow pins 17, projecting from one face of a rigid block or collar 18, carried by the main shaft and held in position by a set-screw or locking-key of any ordinary construction. The collar 18 is provided with a cam-groove 19, the construction of which will be described herein- 5 after, and serving in part to alter the position of the eccentric. The face of the collar is at all times in engagement with one of the faces of the eccentric, and with the opposite face of said eccentric engages a cap-plate 20, 9 through which extend screws 21 to the hollow pin, the collar and cap-plate serving to prevent any movement of the eccentric in a direction lengthwise of the shaft. Both the cap-plate and the collar are recessed, as indicated at 24, each recess being approximately of a double-V shape in contour, and into these recesses extends a slidable cam-block 25, that is movable lengthwise of the shaft by the governor or by a manually-operated lever. The cam-block is provided with two parallel faces 27, inclined with respect to the axis of the shaft and provided at oneend with'a tongue 28, carrying an antifriction-roller 29, adapted to enter the cam-slot 19, and owing to the fact that the collar is rigid in the shaft longitudinal movement of the cam-block and the playing of the roller 29 in the slot 19 will cause said cam-block to receive partial rotative movement independent of the shaft. The opposite ends of the slot 14 are recessed for the reception of wear-blocks 30, which are provided with inclined faces for engaging the inclined faces 25 of the cam, and these blocks are held in place by means of set-screws 32, which may be taken out whenever the block is to be adjusted to compensate for wear, after which the screws are again screwed home and the blocks are rigidly locked, thus affording a ready means for taking up any wear that may occur on the cam proper or on the blocks 30. The function of the cam-block in operating the eccentric is to move said eccentric in a line diametral with respect to the shaft and also to impart partial rotative movement thereto, the extent of both movements being of course proportioned to the extent of longitudinal movement of the cam, and complete movement of the cam serving to reverse the engine by shifting the position of the valve. The cam-block is carriedby a sleeve 36, and this sleeve is grooved or recessed to form a ball-race for receiving balls 37, and the opposite member of the ball-race is formed by grooving the inner face of a collar 39, that is provided with a pair of pins 40, receiving the ends of a bell-crank lever 41, mounted on a suitable stud 42. The arm of the crankle ver to which the collar is connected is in the form of an inherently-elastic strip which will yield to permit operation of the cam-block by the governor, and the opposite arm 43 of the bell-crank lever is connected by a link 44 to any suitable adjusting-lever. On movement of the bell-crank lever in the proper direction the block may be shifted longitudinally of the shaft and the position of the eccentric altered to an extent suflicient to reverse the engine, or the movement may be partial in order to adjust the point of cut-off in accordance with requirements.

The sleeve 36 is provided with a second ballrace 49, the opposite member of which is formed of a grooved collar 50, and said roller is connected by a pair of links 51 to a strap 52, that is mounted on a disk 53, both the strap and disk being curved to form a recess for the reception of bearing-balls 54. The links 51 are held from movement around the shaft by projecting arms 51, bolted to the bearing standard 2, as will be seen more clearly on reference to Fig. 4. The disk 53 is mounted loosely on the 'main shaft 3 and is provided with pivot-ears 55, connected by links 56 to a pair of governor-arms 57. The governor-arms are pivoted on a collar 58, that is rigidly secured to the main shaft, and the ends of said arms are provided with weightballs of the usual character. In the present instance the governor-arm-carrying collar is arranged close to the hub of the balancewheel 63; but it is obvious that the governor may be placed at any desired point in the length of the main shaft, and the several connections between the movable sleeve 36 and the governor-arms may be lessened in number by omitting the disk and strap and the connecting-arms of the collar 50 and connecting the governor-links directly to said collar 50.

In the operation of the parts the engineer may move the manually-adjustable lever and shift the cam-block 25 in a direction lengthwise of the shaft and adjust the position of the eccentric in accordance with circumstances. This movement will be transmitted to the governor, and if the extent of movement is sulficient to reverse the engine the governor-arms will be adjusted to the position shown in dotted lines, so that in one direction of operative movement of the governor-arms the links will act as thrust members to move the cam-block in the direction of the crank-disk; but in opposite direction when the engine reverses the balls will be in the position shown in dotted lines, and the links will act as tension members and tend to move the cam-block away from the crank-disk; but in each case the action of the governor in reducing speed will move the block in the proper direction and tend to center the eccentric, and thus reduce the extent of travel of the valve. Owing to the elasticity of the bell-crank lever 41, the governor is free to operate even when the manually-operable adjusting-lever is locked, so that it is unnecessary to release the lever before the governor can act.

Having thus described the invention, what is claimed is- 1. In a steam-engine, a crank-shaft, a collar rigid with the shaft and provided with a camgroove, a slidable block mounted on the shaft and having a pin or antifriction-roller entering the cam-groove, means for shifting the cam-block, an eccentric having a transverselyextending slot through which the cam-block passes, the side walls at each end of the slot being undercut, wear-blocks having ribs entering said undercut portions, and adjustable transversely of the eccentric, said wear-blocks and the under walls of the slot being each provided with threaded recesses, and lockingscrews extending into the recess for holding said blocks from movementin either direction.

2. The combination in an engine, of a shaft a shiftable eccentric, a longitudinally-movable cam-block for shifting the eccentric, a governor, means for connecting the governor to the block, and means for adjusting the posi- ICC tion of the governor to alter the direction in which movement is imparted to the block.

3. Thc combination in an engine, of an eccentric, a cam-block for shifting the eccentric, a governor including weighted arms, the pivotpoints of which have a fixed plane of rotation,

and means for adjusting the Weighted ends of the arms to one or other side of the plane of rotation thereby to alter the direction in which movement is imparted from the arms to the cam-block.

4:. In an engine, an eccentric-shifting device, a governor including weighted arms that are connected to the shifting device, said governor having pivots arranged in a fixed plane of rotation, and means for adjusting the weighted ends of the arms to one or other side of the plane of rotation thereby to alter the direction in which movement is imparted from the arms to the shifting device.

5. The combination in an engine, of a crankshaft, an eccentric, a cam-block for adjusting the eccentric, a pair of pivotally-mounted governor-arms connected to the cam-block, the pivot-points of said arms having a fixed plane of rotative movement, and means for altering the position of the Weighted ends of the arms to one or other side of said plane of rotative movement thereby to alter the direction in which movement is imparted from the arms to the cam-block.

6. In an engine, the combination with a crank-shaft, of an eccentric, a cam-block for adjusting the position of the eccentric, a sleeve mounted on the shaft and connected to the cam-block, a cut-off adjusting and reversing lever connected to the sleeve, a governor carried by the shaft, a disk rigidly secured to the shaft, and connected to the governor, a strap surrounding the disk, and means for connecting the strap to the-sleeve.

7. The combination in an engine, of a crankshaft, an eccentric, and an adjustable camblock for shifting the eccentric, a sleeve feathered on the shaft, and connected to the block, a longitudinally-adjustable cut-ofi and reversing lever connected to the sleeve, a collar mounted on the sleeve, a governor carried by the shaft, a disk feathered on the shaft and connected to the governor, a strap encircling the disk, links connecting the strap to the collar, and means for preventing rotative movement of said links.

8. The combination in an engine, of a shaft, an eccentric, a longitudinally-movable camblock for adjusting the position of the eccentric, a sleeve feathered on the shaft and carrying the cam-block, a pair of collars mounted on the sleeve, bearing-balls between the collars and the sleeve, a manually-adj ustable cutoff and reversing lever connected to one collar, a disk feathered on the sleeve, a strap encircling the disk, bearing-balls between the strap and disk, a pair of links or rods connecting the strap to the second collar, means for engaging and preventing rotative movement of the links, a governor carried by the shaft and including a pair of weighted arms, and links connecting the governor-arms to the disk, substantially as specified.

9. The combination in an engine, of a shaft, a belt-Wheel mounted thereon, a governor including a pair of Weighted arms, said governor being disposed adjacent to the belt-Wheel, a guard carried in part by the shaft and in part by the Wheel for preventing contact between the belt of the engine and the governor.

10. The combination With an engine,a shaft, a belt-Wheel, a governor arranged adjacent to the belt- Wheel and including a pair of Weighted arms, and a guard comprising a metallic strap having its upper portion secured to the shaft and its end portions secured to the rim of the belt-Wheel.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two Witnesses.

FREDERICK W. BOHN.

Witnesses:

HENRY V. HUFF, JOHN F. KULIG.

Images