US150336A - Improvement in variable cut-offs - Google Patents

Description

G. B. MASSEY.

Varia-ble (lut-MTS.

Patented Agr|28,1874.

UNITED STATES PATENT OFFICE.,

GIDEON B. MASSEY, OF NEW YORK, N. Y.

IMPROVEMENT IN VARIABLE CUT-FFS.

Specilication forming part of Letters Patent No. 150,336, dated April 28, 1874; application filed July 19, 1873.

To all whom it may concern:

Bc it known that I, GrDEoN B. MAssEY, of the city, county, and State of New York, have invented an Improved Variable Gut Off, of which the following is a specification:

The object of this invention is to obtain a cut-0H 'gear which will be variable under' the control of a governor, and through which the cut-off valve will not only be opened, but also closed, by a positive action derived from the shaft of the engine, without aid from the force of gravity, resilience of springs, or pressure of steam. The invention consists in a novel and simple system of pins or offset-surfaces of different length and projection, carried by a rotating shaft, and a variable toe attached to the valve, whereby the positive invariable opening, and the positive but variable closing, movements are effected. It also consists inthe combination of aslotted arm, arranged on the A yoke of the valve-rod, a toe made to slide in the same toward and from the valve-rod, and a lon gitudinally-moving rod, which constitutes the controlling agent of the governor, and is transversely grooved near its outer end, to flt a rib on the head of the aforesaid toe, whereby the governor is made to control the shifting of the toe, and, consequently, made to regulate the cutting off the induction of steam to the engine-cylinder.

In the accompanying drawing, Figure 1 is a plan view of my improved cut-olf, showing the valve of the engine to which it is applied. Fig. 2 is a section of the same, taken transversely through the yoke of the valve-rod, and representing4 a side View of the governor ofthe device; and Fig. 3 is a sectional view of the cutoft', taken close to the valve-rod.

Similar letters of reference indicate correspending parts in the several figures.

Arepresents the cut-off valve of a steam-engine. B indicates the rod by which it is operated. Motion is imparted-to this rod by pins or wrists on a disk, G, fitting within a yoke, b, provided on the rod for its reception. The rod is impelled forward in a direction to open the valve by a wrist, a, arranged alone on one side ofthe disk or wheel G. In the revolution of the wheel this pin strikes a projecting piece, o, situate on the adjacent side of the yoke of the valve-rod, and so pushes the rod along. This movement is ever the same throughout all the variations of the cut-off.

The backward movement of the rod, effecting the closing of the valve and cutting olf of the steam, is produced by separate means. 0n the other side of the disk C there is arranged a series of wrists or pins, p p1 p2 p3 p4, which decrease in length, from the irstto last of the series, in regular gradation. A sliding toe, D,

'is arranged on the valve-rod yoke in such po sition that it can be thrown out into contact with one or another of these pins, and according to which is thus rendered the operative one, so will the cutting off of the steam take place sooner or later in the stroke of the engine. In the drawing this toe is represented as being arranged in a slotted arm, E, situate on the middle portion of the upper side of the valve-rod yoke. It is thus enabled to slide toward and from the valve-rod, to come into contact with one of the wrists p p1, Sac., as just described. The toe D has a head, which lits above the slotted plate, and shoulders, that lit below it. On its head there is along rib, t', which lits into a transverse groove in the rod G of the governor l, that shifts its position on the arm E. This rod G has no rotary motion whatsoever, but simply a longitudinal movement. The said rod lits within the spindle l of the governor I, and the sliding collar of the governor is connected with it in such manner as to permit the free rotation of the governor, the turning of the said rod being prevented by a pin located in one of the governors bearings J J, so as to project intova groove'provided in the rod. The spindle P of the governor extends through the bearing next the valverod, and, at the outer end, is furnished with a pulley, S, to receive the belt by which motion is imparted to it. There may be a nut arranged on the governorspindle beyond the spring, to afford a means of compressing it more or less, in order to set the governor to regulate the running of the engine at a greater or less speed.

The operation of this cut-oft' is as follows: As the wheel C revolves, the wrist a comes in contact with the projection o on the yoke of the valverod, and pushes the valve forward, so as to open it. The `backward cutting off movement of the valve is effected by one or other of the pins or wrists p p1 p2, &e., coming in contact with the sliding toe I) carried by the eccentric rod. As soon as the slightest tendeney to variation in the speed of the engine occurs, and the arrns of the governor, in their gyrations, are more or less distended, so the toe is moved farther out or in, and is thrown into contact with a shorter or longer wrist. The distension of the balls brings the toe into Contact with one of the shorter wrists, and the steam is cut oi sooner in the stroke of the en gine. As soon as the speed decreases, the tongue is drawn by the governor inward, -so that it only gears with the longer pins at the end ofthe series, and cuts oii' the steam only near the end of the stroke.

Instead of the wrists 1J p1, &e., a disk or wheel having its face or periphery correspondingly graduated may be employed.

In applying the invention to areciprocating engine with a single cutoff valve independent ofthe main valves, the disk C must niake two revolutions for every one of the inain shaft of the engine. In engines which use the saine valves for induction and cutoffone valve at each end of the cylinder-the cutoff gear inust be duplicate. In applying the invention to a rotary engine, a single set of cut-off gear only will be necessary 5 but the disk C must revolve as many times for each revolution of the main shaft as there are pistons to the engine.

rJheI governor may be dispensed with, if desirable, and the tongue will then be adjusted, by a screw or other means, to eut oft' at such point as may be desired.

A great advantage of this eut-oft` gear is, th at the eut-off valve is always left full open, no matter in what position the engine stops.

'W hat I claim as iny invention is l. The combination of the iixed projection C and movable toe D, attached to the valve-yoke on opposite sides oi' the valveop'erating shaft, and the opening wrist or pin co, and series ot' closing wrists or offsets p p1 p2 123194, of diterent length or projection, carried by the said shaft, substantially as herein described.

2. The combination of the slotted plate E, the sliding toe D, and the governor-rod G, essentiall y as and for the purpose herein specified.

G. B. MASSEY.

lVitnesses:

HENRY T. BROWN, MICHAEL RYAN.

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