US322711A - Cut-off valve - Google Patents

Description

(No Model.)

2 Sheets-Sheet 1. I O. HARMON.

GUT-OFF VALVE.

Patented July 21, 1885.

N. PETERS. Phvtwmnogn lwr, Washinglon, 04 C.

2 Sheets-Sheet 2.

(No Model.)

0. HARMON.

GUT-OFF VALVE.

No. 322,711. Patented July 21, 1885.

y m I IIIIIM u m llllllll. l l hrl' illllll AT THE 5- N. PETERS. Phum-Lflhugnphur, Washington. a. c.

I ATENT Ormce.

CHARLES HARMON, OF TIFFIN, OHIO.

CUT-OFF VALVE.

SPECIFICATION forming part of Letters Patent No. 322,711, dated July 21, 1885.

Application filed April 29, 1885.

. drawlngs.

This invention has for its object to provide an improved balanced piston-valve and automatic cutoff for steam-engines; and it consists of mechanism to impart arotary motion, in addition to the usual longitudinal motion, to the valve-stem, and of the construction of valve and its seat employed in connection with the foregoing mechanism; also of a governor, substantially as hereinafter more fully set forth and claimed.

In the accompanying drawings, Figure 1 is a plan view, partly in section, a portion also of the steam-chest being broken away, of the parts of a steam-engine embodying my improvements. Fig. 2 is an elevation, also partly in section, thereof. Fig. 3 is a transverse section taken through the piston-cylinder and steam-chest, also showing in section a valveseat. Fig. 4. is a detailed view showing in side view the valves, the same being connected together.

Althoughlhave herein shown the eccentricshaft, the piston and its cylinder of a steamengine, they form no part of these improvements, the same only being illustrated to more fully show the application of the invention, and therefore need nothere be further referred to, the invention or improvements, as before intimated, pertaining more particularly to the piston valve or valves and their seats, and to appliances for rotating the valve-stem together with their valves, in connection with which, as before stated, is employed a governor. Therefore, in the embodiment of my invention I construct or east the steam-chest A with internal circular, or cylindric valve chambers or seats B, one being disposed near each end of the chest, the edges of the walls of which chambers, at their upper surfaces, being cast or made integral with the inner top surface of the chest. Intermediately of said chambers or valve-seats is the live-steam chamber 0, its

(No model.)

continuous side and bottom walls being cast integral, and flush with the bottom and side walls of the valve seats or chambers B, to which live-steam chamber steam is admitted or supplied from the boiler, in practice, by a pipe connecting with the opening or aperture a in the top thereof. D is the exhaust-steam chamber, occupying the space between the easing of the steam-chest and the Walls of the live-steam chamber and the valve chambers or seals. Said exhaust-chamber communicates by means of the ports or orifices bin the outer end walls of the valve chambers or seats with said latter chambers or seats, and exhausts either through a port, d, in its end, or through a port, d, in its bottom. The valve chambers or seats are each provided with one or more ports, f, arranged around the circle at suitable or equal intervals apart and communicating with passages or ports, 9, leading to the piston-chamber I.

E E are the valves, which are of corresponding shape with and fit in the valve seats or chambers 13, said valves being two in number and connected together by an intermediate rod, e, with their stem 6' steam-packed where it passes through one end of the steam-chest, and connecting with the eccentric-rod F of eccentric F on the driving-shaft, which eccentric is fast on the shaft G, which valve-stem will be further referred to presently. The valves E are hollow or chambered, each having one end closed and its open end disposed toward the open end of the other, or inwardly, while in the casing of each valve is a corresponding or coincident arrangement of one or more ports, h, with the portsf of the chambers or seats B of said valves. These valves receive or take the steam from the live-steam chamber 0, and, through their ports h, feed it alternately to the ends of the pistonchamber through the passages or ports 9, and alternately exhaust the steam, after having done its duty upon the opposite or alternate sides of the piston through the said ports and the openings in the outer ends of the valve chambers or seats into the chamber D, when the exhausted steam passes, as hereinbefore pointed out, into the open air. To enable these valves also to act automatically as cut-offs they also have in addition to their longitudinal movement, as before stated, a rotary reciprocating movement, the mechanism to effect which will now be described.

The valve-stem e is supported near its outer end, which may be enlarged, as shown at 6 in a hearing or box, 2', formed upon the upper end of a bracket, 2', cast with or bolted to the supporting-framej, and upon or to the lower end of which bracket is cast a cylindric arm or shaft, k, the purpose of which will appear further on. The extreme outer end of the valve-stem is flexibly connectedit may be, by a ball-andsocket joint, as at Zto the cocentric-rod or pitman F to permit the valvestem to revolve or turn upon the latter and move longitudinally in a straight line while permitting the rod or pitman, in its movement, to conform to the action of the eccentric F upon the drivingshaft G.

L is a bell-crank lever having at its angle or the point of conjunction between its arms, one of which latter is longer than the other, a sleeve, 7c, which fits upon the arm or shaft 7c, previously described, and upon which shaft it is adapted to have movement. The longer arm of the bell-crank lever L is connected or pivoted to a pitman or rod, M, actuated by an eccentric, M, upon the drivingshaft G. The short arm of the bell-crank lever is connected or pivoted to a rocking arm or lever, N, pivoted or jointed at its upper end to a collar, m, clamped upon the valve-stem c, said latter end of rocking arm or lever having a vertically-adjustable sleeve and clamp connection, as shown, with a stud or pivot of the collar, whereby said connection may be relatively varied to increase or diminish the distance between the short arm of the bell-crank and the valve-stem, as one means of varying the rotation or of equalizing the time of out off of steam by the valves.

It will be seen that upon actuating the ec-- centric-rods or pitmen the valves with their stem will receive a reciprocating longitudinal movement, as also a rotary reciprocating movement, the latter resulting from the action of the bell-crank lever and its pitman or eccentric-rod, and its rocking-arm connection with the valve-stem, the valve-stem, through the ball-and-socket joint connection with its eccentric-rod or pitman, being free to have a rotary reciprocating movement under the action of the bell-crank lever, which rotary reciprocating movement of the valves intermediately of the maximum limit of each. movement or stroke, each way of the valves, alternately cuts off the passage of steam through the valves to or from the piston-cylinder.

In order to control the rotary reciprocating movement of the valves, to accomplish which the rotary movement of the valve-stem, of

course, must be varied, a governor is secured upon the driving-shaft G, said governor comprising a wheel, 0, fast to the shaft, whose spokes n are longitudinally slotted to receive and contain blocks or heads 0, normally resting at the bottoms or inner ends ofthe spokeslots. These blocks or heads are loosely arranged upon rods o, encircled by springs 1), bearing at their outer ends upon the rim of the wheel and at their inner ends upon said block, hold-ing the latter under a certain amount of pressure, said blocks, however, yielding or moving outward when exposed to a certain amount of centrifugal force. To these heads or blocks are connected or pivoted. the one ends of curved arms or bars q, the opposite ends of said arms or bars being also connected or pivoted to a disk, P, sleeved at P upon the shaft G, said sleeve 1? being loose on the shaft and also carrying the eccentric M, which is also loose on shaft of the pitman M, connecting'with the bell-crank lever L,

rotating the valves B, the action before ascribed to said governor upon the rotary recip-- rocatory movement being obvious from the foregoing.

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

1. The combination, with the connected rotary valves fitted as feed and exhaust valves to piston-chamber and the bell-crank lever connected to the rotary valve-stem and to an eccentric-rod or pitman,of the governor-wheel fast to the driving-shaft, and comprising the spring heads or blocks connected by pivoted arms to a disk sleeved upon the driving-shaft, said sleeve also carrying the eccentric of the bell-crank lever, pitman, or rod, substantially as and for the purpose specified.

2. The bell-crank lever and its pitman or rod, in combination with the stem-actuating pitman or eccentric-rod, constructed and arranged, as shown, for imparting a reciprocating rotary and longitudinal movement to the valves, substantially as described.

3. The combination, with the connected circular valves, of the steam-chest, and the internal circular valve-chambers integral with said steam-chest, and the valve-stem, together with its eccentric-rod, a pitman or rod, and a bell-crank lever having one arm connected to said pitman or rod andthe other to the valvestem, arranged and adapted to operate substantially as shown and described.

In testimony whereof I affix my signature in presence of two witnesses.

CHARLES HARMON.

Witnesses:

HUBERT SERvos, HENRY BROI-IL.

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