US285500A - Cut-off-valve gear - Google Patents

Description

4.H I-I-MBYER. GUT-OPP VALVEy GEAR.

(No Model.)

Patnltierd Sept.

"fiestarA'rES Ein HERMAN H. MEYER, OF DENVER, COLORADO.

CUT-OFF-VALVE GEAR.

SPECIFICATION forming part of Letters liatent No. 285,500, dated September 25, 1883.

Application filed March 30, 1883. (No model.)

To all whom z'z/ may concern.-

Be it known that I, HERMAN H. MEYER, a citizenof the United States, residing at Denver, in the county of Arapahoe and State of Colorado, have invented certain new and useful Improvements `in Automatic Cut-Off-ValveV Gears for Steam-Engines, o f which the following is a specification, reference being had therein to the accompanying drawings.

My-invention relates to that class of steamengines in which counter-weights arranged in a disk attached to the main shaft of the engine act through centrifugal force upon an eccentric moving on said main shait and connected tothe slide-valve in the steam-chest by a series of rods and crank-arms, and thereby automatically control or govern the movement of said slide-valve; and my said invention consists in certain novel combinations of parts, as will hereinafter more fully appear, and which will form the subject of specific claims.

Referring to the drawings, in which similar letters of reference indicate like parts in the several views, Figure 1 represents a side elevation, partly in section, of my improved arrangement of automatic governor or cut-off for steam-engines, and Fig.' 2 a plan of the same. Fig. 8 is a sectional view of a pistonvalve to which my proposed arrangement is applicable, the same as to the ordinary slidevalve shown in Eig. 2. Fig. 4c represents the position of the eccentric ofthe governor should the speed, of the engine be increased suiciently to act upon the centrifugally-acting weights which operate said eccentric.

A is the cylinder, and B the steam-chest, of an ordinary steam-engine. B is the slidevalve, and b its rod. This slide-valve is operated by the fixed eccentric E on the main shaft of the engine, connecting-rod e, vibrating arms J K, connected by link j, and valve-rod b. D is another eccentric, also on the main shaft, and acting through rod Z and rocker-arms L and K to move the slide-valve B. C is a disk containing the automatically-acting valvegoverning devices, keyed-to the main shaft of the engine, Within this disk C is arranged the counter-weights RF', and H, which act upon a lever, D, pivoted to the disk O at d', and having an elliptical opening, d, in its large end, through which passes the main shaft of the engine.; To this lever D the eccentric D is secured, and moves with the disk C. The counter-weight F is attached by a short rod, lf', directly to the lower part of the enlarged end of the eccentric-lever D', while the similarly-formed weight F is connected to said eccentric-lever D through a rocker-arm, O, pivoted at o, and alink, l?, pivoted to the short end of the rocker-arm O, and to the eecentric lever D at p. These weights F and F have side roller-bearings, f, and by reason of their gravity, combined with the springs G G', act to keep the eccentric-lever in the proper eccentric position, as shown in Fig. l-that is, with the main shaft at one end of the slot d thereof. The counter-weight H is of different construction from the ones F a'nd E', being pivoted at 71 to the disk C, and engaging by a short arm with a short projecting end of the eccentric-arm D, as shown at h. The action of this weight is the same as that of the ones F Fwthat is, to keep the eccentric-arm D in such position that the main shaft will be at one end of the slot d thereof, as shown in Fig. l. G G are spiral springs, the one G arranged to act against the eccentric-lever D, and the one G' arranged to act against the short arm or end of the pivoted weight H.

The object of the foregoing-described parts is to form a secondary means for acting upon the slide-Valve, in connection with the usual eccentric and its connection, which shall be brought into action automatically by the centrifugal force of weights acting upon an eccentri c, should the speed ofthe engine be increased sufiiciently to cause these weights to act and close the steam-ports, thus forming an automatic governor to regulate the speed of the engine. f

The operation is as follows: The first eccentric,E,is set opposite in position to the piston crank-arm I, and is connected with the valve-rod b by a rod, e, pivoted to a rockerarm, J, having a central pivot at 1 on the frame of the engine, and a similar arm, K, to which the valve-rod is attached, having a pivot bearing at 3. on the rocker-arm L, and connected to the arm J byalink, j. The travel of this eccentric E is only slightly in excess ofthe lap of the valve*that is, the movement is just sufficient to open the port for the admission of IOO steam at the beginning of the stroke, as shown in Fig. 2. Should there be no other provision, the eccentric E would simply opeii the ports, as shown, just suiiieient to admit steam, and then at once commence to closethe ports again; but at the moment the eccentricE nishes its forward stroke, bringing the valve in the position shownin Fig. 2 the eccentric D revolved by the disk C, commences to act, and through its rod Z, pivoted to an arm, L, rocking on a bearing on the engine-frame at 2, and pivoted at 3 to the rocker-arm K of the valve-rod b, continues the forward movement of the valverod and carries the valve over the steam-ports its full stroke. The same movement takes place on the reverse stroke, so that the proper movement for the valve is obtained. Should the speed of the engine increase suflieiently to cause the Weights F, F', and H to move by centrifugal force from the center, they, through their connections, cause the eccentric-lever D to move from its normal position (represented in Fig. l) and assume the position represented in Fig. 4, with the 'main shaft in a central po# sition,which being a non-eccentric one, or one of no eccentricity, the eccentric D ceases to vibrate, the rockerarm L assuming a vertical position, as shown in Fig. 1, and the steam is eut off' fromY a point just sufficient to move the engine by the iixed eccentric. In other words, the eccentric D ceases to act, and the iiXed one E being adjusted through the rocker-arm J, pivoted at l, and rocker-arm K, pivoted to the arm L at 3, so as to move the valve only so as to just lap the ports, the volume of steam admitted is decreased, and consequently the rapid movement of the engine at once ceases. Upon the slaekening of the revolution of the disk C consequent upon the diminished amount of steam admitted by the ports, the weights lose their centrifugal momentum, and the springs G G',which had been compressed by the action of the weights, are permitted to react upon the eccentric-lever D and bring the eccentricA D back to its normal or eccentric position, as shown in Fig. 1,when the eccentric D is again brought into play and the arm L vibrated and the full stroke given thereby to the valve. rIhis movement, imparted by the weights to vthe eccentric-arm, and through its eccentric D and rod l, causes the arm L to vibrate a greater or less degree, according to the speed ofthe engine, and to correspondingly. act through the rod Z1 uponthe valve in the steam-ehest, and thereby give more or less travel to the valve, and opening or closing the steamports accordingly.

The engine may be run entirely by the eccentric E, in case of damage to the cutoff mechanism, by shifting the eccentric to an opposite position, disengaging the rod c from its present position at the top of the rocker-arm J, and securing it to the bottoni of said arm, throwing off the connecting-link j, and substituting a longer valve-rod for the one Z) that will reach from the top end of the arm J to the slide-valves.

What I claim isl. In an engine-valve gear, the rocker-arms J K and arm L, the'link j, connecting said arms J K, the rods e Z, and valve-rod b, in combination with the eecentrics D E, one being free to move across the shaft, and the diskgovernor C on the main shaft of the engine, substantially as and for the purpose set forth.

2. In an engine-valve gear, the combination, in a disk-governor, of the disk C, weights F F', and pivoted weight H 7L, lever O, and its link I), the eccentric arm or lever D', pivoted to the side of the disk, and the springs G G', arranged to act upon the eceentric-ar1n D', and pivoted weight H, respectively, all arranged to operate as and for lthe purpose set forth.

3. In an engine-valve gear, the combination, with the rocker-arms J, K,and L, and the link j, connecting said arms J K, ofthe eecentrics D and E,rods e and Z,valverod Z), disk @,weights F F', pivoted weight H, lever O, and its link I?, arm D', and springs G G', all combined and arranged to operate as and for the purpose set forth.

In testimony whereof I have affixed my sig-l nature in the presence of two witnesses.

HERMAN H. MEYER. lVitnesses:

GEORGE E. Ross-LEWIs, STEPHEN H. CAMPBELL.

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