US399397A

US399397A - garst

Info

Publication number: US399397A
Authority: US
Publication date: 1889-03-12
Anticipated expiration: 1906-03-12

Description

3 Sheets-Sheet 1. E. GARST.

(No Model.)

VALVE GEAR.

-1 .1 i a N 1 l NW m A A &

P l W m kmww 3 a Y v W W M: \n W ATTORNEY.

N. PETERS, mnwmo mn Washington. D. c

(No Model.) 3 Sheets-Sheet 2.

E. GARST.

VALVE GEAR.

No. 399,397. Patented Mar. 12, 1889.

WITNESSES: l/VVE/VTOH:

(No Model.) 3 Sheets-Sheet 3 E. GARST.

VALVE GEAR.

No. 399,397. Patented Mar. 12, 1889.

WITNESSES. INVENTOR: %w a? i, BY U JAM/11.)

.19 ATTORNEYS.

irnn drarns PATENT OFFICE.

ETHYIN GiUlSl, OF DAYTON, OHIO, ASSIGXOR TO HIMSELF AND \YTLBER ll'l lA'lllltAN, OF SAME PLACE.

VALVE-G EAR.

SPECIFICATION forming part of Letters Patent No. 399,397, dated March 1.2, 1889.

Application file-Ll June 28, 1883- Serial No. 278,407. (No model.) 7

T0 aZZ 2071mm it may concern.-

Be it known that I, EDWIN GARs'i, of l)avton, in the county of Montgomenv and State of Ohio, have invented a new and Improved Valve-Gear, of which the following is a full, clear, and exact description.

The invention relates to valve-gears for steam-engines.

The object of the invention is to provide a new and improved valve-gear which is simple and durable in emistructionand automatic in operation, using steam expansively.

The invention consists of certain parts and details and COllllJlilfitlOl'lS of the same, as will it be fully described hereinafter, and then pointed out in the claims.

Reference is to he had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresp'omling parts in all the figures.

Figure l is a plan view of the improvement as applied. Fl 2 an enlarged transverse section of the improvement on the line wacof Fig.1. Fig. 3 is an enlargerfl sectional side elevation of the same on the line 1 y of Fig. 1. Fig. 4. is an enlarged sectional side elevation of the improvement on the line 2 z of Fig. 1. Fig. 5 is an enlarged plan view of the inletvalve and its stem detached. Fig. 6 is a sectional side elevation of the same on the line to u of Fig. 5. Fig. 7 is a plan view of the exhaust-valve and its stem detached. Fig. 8 is a sectional side elevation of the same on the line 1' r of Fig. 7. Fig. 0 is a perspective view of a cam.

In the steam-cylinder A operates the piston 13, connected with the piston-rod 0, carrying at its outer end a cross-head, D, mounted to slide in guideways E, and pivotallv connected by the pitman F with the crank-arm G of the main driving-shaft G of the engine. In the end of the cylinder A are formed the two ports o and b, leading to the steain-chests i i l i and operated on by a lever, l, pivotall connected l'rvthe red .I with the frame 1i, mounted to slide longitudinally in the bearings K,

located directly under the main driving-shaft G. The inner end of the lever I acts alternately on the ends of the valve-stems H and H so that the slide-valves ll and H are actuated alternately from the said lever I in order to open and close the live-steam ports (I and h, leadin to the cylinder.

Each of the valve-stems ll and ll is piv otally connected with a lever, ll, fulcrumed on the cylinder A and pivotally connected with a rod, H, mounted to slide in suitable hearings held on the cylinder A. On the outer end of each rod ll is coiled a spring, ll", one end of which rests against the said hearing and the other end rests againstthe adjusting-nut H fastened on the outer end of the rod ll. The spring ll. has the tendency to close the slide-valve II or 11 whenever the respective valve-st em ll or ii is disengaged by the lever I.

The longitudinally-sliding frame K carries two rods, K and K, held transversely on the said frame K and in a horizontal plane with the main driving-shaft G. On the rods K i and K is held to slide transversely frame,

A and A connected with each other by a 1 i N is provided on its other arm, N with a channel, A. into which leads the steam-inlet pipe A".

Over the port s (It a nd I operate the slide-valves H and H, rcspecti vel v, provided with the ports ct and 1), formed to register with the ports 0 and 1'), leading from the steam-chests A and A to the cvlinderA. The slide-valves ll and H are connected with the valve-stems II and l l l 1 loosely on the said rods K and K respectively. The friction-wheels L and L are operated on by a cam, G'-, secured to the main driving-shaft G and provided. with a spiral ridge, G fully shown in perspective view in Fig. 9.

The frame L is secured to a transverse rod, L held to slide in suitable hearings in the frame A, and pivotally connected with a link, L, pivoted on the arm N of a hell'crank lever, N, fulcrumed on a suitable bracket on.

the main frame of the governor 0, located at 9 one side of the main driving-shaft G and operated from the latter. The hell'crank lever weight, N held adjustahly on the said arm N and the latter also provided with pins X projecting into an annular groove formed in the collar 0, held to slide vcrticall3 on the shaft 0', mounted to rotate in suitable bearings on the governorframe, and, carrying on its lower end a bevel gear-wheel, meshing H respectively, extending toward each other l into a hovel gear-wheel, 0 secured on one end of a shaft, 0, running parallel with the main driving-shaft G, and mounted to rotate in suitable bearings on the governor-frame. On the shaft O is secured a pulley, 0, over which passes an endless belt, 0 also passing over the main driving-shaft G, which, by the said belt, imparts movement to the governor O.

The collar 0 is connected with the ends of ropes or chains P, passing over the pulleys P, mounted to rotate in a frame, 1, secured to the upper end of the vertical shaft 0 and the upper ends of the ropes P are secured to the weights P held to slide in opposite directions on a rod, P, also secured on the upper end of the vertical shaft On each outer end of the rod 1 is secured a collar, P to limit the outward movement of'the weigh ts P and the latter are connected with each other by springs P, which serve to draw the weights P inward toward each other after having been moved outward by the centrifugal force of the governor O. The weights P take the place of the usual balls of governors and operate in a similar manner to the same.

From the cylinder A also lead the two exhaust-ports e and (1, opening into the exhaustchambers A and A, from which lead. the ports e and f into a pipe, A connected with the exhaust-pipe A leading to the outside. The ports 0 c and (Z fare located opposite each other, and are connected with or disconnected from each other by slide-valves Q and Q, respectively, having the ports 0' and d, respectively, adapted to register with the ports 0 e and [1 respectively. The slidevalves Q and Q. are connected with each other by a valve-stem, Q pivotallyconnected with a rod, Q pivoted on the arm R of a T- shaped lever, R,f ulcrumed at R to a bracket on the main frame of the engine. The pivot R is located in the middle of the guideways E, so that the cross-head travels the same distance on each side of the said pivot. The lever B is also provided with the arms R and 3?, extending in opposite directions and at right angles to the arm R, each of the arms R and B being bent upward at the outer ends, R and R, as is plainly shown in Fig. 4, and the said curved ends R and R being alternately engaged by a friction-wheel, D, held on the cross-head D.

The operation is as follows: \Vhen the pis ton B- is in the position shown in Fig. 4, the live steam entering the steam-chest'A passes through the, ports 6 and 1) into the cylinder A and pushes the piston B forward in the direction of the arrow g. A rotary motion is thus imparted to the main driving-shaft G in the direction of the arrow h, so that the cam G' acts on the friction-wheel L and holds the frame Kin its extreme outward position, so that the rod J connected with the lever I, holds the slide-valve H in the position shown in Fig. at, whereby the portb registers with the port I), as above mentioned. hen the cam G has traveled from the point i to the point 5, the slide-valve H remains in this position, and when the cam passes over the wheel L from the point 5 to the point 6 the lever I swings to the other side, and, the spring H presses on the rod H the lever 11' forces the valve-stem H to the left, so that the port 11 in the cylinder is closed by the slide valve II. The piston B is then near the end of its stroke, and the part 1 of the cam G now comes in contact with the friction-wheel L and from 2 to 3 moves the valve the lap, so that the frame K is moved forward and the lever I commences to act on the valve-stem H whereby the slide-valve H is moved in the direction otthe arrow g and the port a opens into the port a, when the cam G travels from the point '3 to the point 4-, at which latter point the ports are fully opened. The live steam now enters through the steam-chest A into the inner end of the cylinder and forces the piston ll in the reverse direction of the arrow g. \Vhenthe piston 13 is in the-position shown in Fig. 1:, the slid e-valve Q disconnects the ports (I and f, while the slide-valve Q connects by its port 0 with the cylindenport c and the exhaustport e. \Yhen the piston travels in the direction of the arrow 1, the eXlniust-steam in the cylinder A in front of the piston can pass out through the ports (1, c, and c into the exhaustpipe A \Yhen the piston ll nears the end of its stroke, the friction-wheel l) on the crosshead D comes in contact with the curved end of the lever B and causes the latter to swing in the direction of. the arrow L whereby the rod is moved in the reverse direction of the arrow g and the position of the slidevalves Q and Q is reversed, so that the ports 0, c, and e are disconnected and the ports (I, d, and f are connected with each other. \Vhen the piston now travels in the reverse .direction of the arrow g, the exhaust takes place through the ports (7, d, and f in the same manner as above described in reference to the ports 0, c, and e. W'hen thepiston B travels in the reverse direction of the arrow g and nears the end of its stroke, the friction-wheel D comes in contact with the curved end R of the lever B and causes the latter to swing in the reverse direction of the arrow '17, whereby the position of the slide-valves Q and Q is again reversed to the position shown in Fig. 4. WVhen the engine runs at a normal rate of. speed, the frame L, carrying the friction-wheels L and L stands at about the middle of the cam G so that the part of the cam G coming in contact with the said friction-wheels L and L as above described, opens and closes the slide-valves H and H regularly. hen the speed of theengineincreases, the governor-weights P 'slide outward and pull thecollar O upward by theropes P, so that the bell-'crank'lever N is set in motion and moves the link L, the rod L and the frame L transversely in the direction of. the arrow 10, whereby'the cam G acts. on the frict-ion-wheels L and L and thereby the valves 11 and H are closed sooner, and consequently less steam is admitted to the cylinder A. The speed of the engine is thus decreased, and when the normal speed is attained the governor-weights P assume their form er position by the action of the springs P whereby the collar O is again moved downward to its former position by the act-ion of the weights P on the bell-crank lever X, and the latter, the link L the rod L and the frame L also assume their former positions, and the valves II and H are again opened and closed regularly. lVhen the speed of the engine decreases, the springs P draw the weights P still farther inward, so that the bell-crank lever N shifts the frame L transversely in a direction opposite to that described, whereby the cam G holds the slidevalves H and H open a longer time, so as to admit more steam to the cylinder A. An increase of speed is thus obtained until the normal speed is reached and the weights P of the governor 0 again assume their original positions, whereby the frame L is moved to the middle of the cam G and the valves H and H again open and close regularly.

It will be seen that as the cam G is uniform in cross-section at

points

2, 3, and t the valves H and H always travel their full stroke,- but close sooner or later, according to the position of the frame L on the spiral cross-section of the cam G As the piston B always travels into full stroke, the exhaust slide-valves Q and Q are opened and closed regularly, as above described by the action of the frictionwheel D on the lever B, connected with the stem Q of the said valves.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The coi'nbination,with the rotary cam,of a longitudinally-slidingvalve-operatingframe and a transversely-sliding frame thereon embracing a cam, substantially as set forth.

2. The combination, with a shaft having a fixed cam provided with a spiral ridge, of a 1011 gi tud i nall v-slidin g val ve-operatin g frame under the cam at right angles to the shaft, and provided with a curved frame extending over the cam and having front and rear friction-wheels for the cam to engage, substantially as set forth.

3. In a valve-gear, the combination, with a spiral cam secured to the main driving-shaft, of a frame mounted to slide transversely and carrying friction-wheels acted on by the said spiral cam, a second frame carrying the said. first-named frame and connected with the steam-inlet valves, and a governor operated from the main driving-shaft and controlling the transverse motion of the said first-named frame, substantially as shown and described.

4. In a valve-gear, the combination, with a main driving-shaft and a spiral cam secured to the said main driving-shaft, of a frame mounted to slide transversely and carrying friction-rollers acted on by the said cam, a

second frame, mounted to slide longitudinally, carrying the said first-named frame and connected with the steam-inlet valves, and a governor operated from the said main drivingshaft and controlling the transverse move ment of the said first-named frame, substantially as shown and described.

5. In a valve-gear, the combination, with steam-inlet valves and a lever for controlling the said inlet-valves, of a frame held to slide and connected with the said lever, a second frame held to slide transversely on the said first-named frame, and a governor for controlling the transverse movement of the said second frame, substantially as shown and described.

6. The combination, with the crank-shaft, the cylinder, its piston, steam-chests, inlet slide-valves having stems extending toward each other, and exhaust-valves connected bya rod, of the cross-head connected to the pistonrod of said cylinder and operated by said crank, a cam on the crankshaft, alever extend ing between the two stems of said inlet-valves and oscillated by said cam, a rocking lever actuated by said cross-head, a rod connected to said lever and to the rod connecting the exhaust-valves, and a governor for changing the relation of the inlet-valve operating frame with respect to the cam, substantially as set forth.

7. In a valve-gear, the combination, with a main driving-shaft, of a spiral cam secured on the said main driving-shaft, friction-wheels acted on by the said spiral cam, a frame mounted to slide transversely and carrying the said friction-wheels, a second frame carryin g the said first-named frame and mounted to slide longitudinally, being also connected with the steam-inletvalves, a rod secured to the transversely-shding frame, a link pivotally connected with the said rod, and a bellcrank lever pivotally connected by one arm wit-h the said link, its other arm being acted on by the governor, substantially as shown and described.

8. In a valve-gear, a main driving-sha t, a governor operated from the said main driving-shaft, and a spiral cam secured on the said main driving-shaft, in combination with friction-wheels operated on by the said cam, a frame mounted to slide transversely and carrying the said friction-wheels, a second frame mounted to slide longitudinally and carrying the said first-named frame, being also connected with the steam-inlet valves, a rod secured on the said transversely-sliding frame, a link pivotally connected with the said rod, and a bell-crank lever pivotally connected by one arm to the said link, its other arm being acted on by the said governor, substantially as shown and described.

EDIVIN GARST.

Witnesses:

D. K. ALLISON, W. G. LAWRENCE.