US624512A - Valve apparatus - Google Patents

Description

No. 624,5l2.

F. A. ILITTLEFIELD.

VALVE APPARATUS.

(Application filed May 7, 1898.)

Patented May 9, I899.

(No'ModeL) ihnrn ATENT. rnicn.

FRANK A. LITTLEFIELD, OF NASHUA, NElV HAMPSHIRE;

VALVE APi-ARATUS.

SPECIFICATION forming part of Letters Patent No. 624,512, dated May 9, 1899. Application filed May 7,1898. Serial No. 680,051. (No model.)

To a, whom, it may concern:

Beit known that I, FRANK A. LITTLEEIELD, of Nashua, county of Hillsborough, State of New Hampshire, have invented an Improvement in Valve Apparatus, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention relates to valve apparatus particularly adapted for highpressure service; and the invention has for its object the construction of. such apparatus whereby but little manual power is required to effect the opening and closing of the valve.

The valve mechanism to be described is readily adapted for use with ordinary globevalve cases or shells, and when the valve-face becomes worn it may be readily replaced.

Figure 1 is a vertical section of a valve apparatus embodying my invention with the main valve closed; and Fig. 2 is a similar view, but showing the main valve open.

The valve case or shell A may be of the well-known and so-called globe-valve construction, having an inlet A and an outlet Aand interiorly divided bya perforated diaphragm 'or wall A forming an annular mainvalve seat a. A removable cap A is shown as screwed onto the case above the saidvalveseat and provided with a suitable stuffingbox A I have herein shown the main valve as composed of a disk I), having oppositely-turned annular flanges Z2 b and a central hollow hub b exteriorly threaded to receive a retainingnut b shouldered at 19 the hub being located on the under side of the disk. A ring b of soft metal or other suitable material, is held within the flange 6 between the disk and the shoulder b of the nut, the latter securely retaining the ring in place, the exposed portion of said ring forming the face of the valve to contact with the seat ct. The flange Wis considerably deeper than the flange b and is herein shown as threaded at 1)? to engage the threaded periphery of a top piece 0, havinga central opening terminating in an auxiliaryvalve seat 0 which communicates with the chamber 0, formed by the disk I), its flange bf, and'the top piece 0. The valve-stem d, extended through the stuffing-box A is en larged to form a head (1 on its lower end to enter loosely the opening in the top piece 0,

the bottom of the head being shaped to constitute an auxiliary valve d to open or close the valve-seat o the bevel of the end of the head (1 being slightly less than that of the seat a, so that contact will be in substantially an annular line and not over the Whole face of the seat. through a slot d in the head (l and is held firmly in a hub c on the top piece 0 to permit a limited movement. of the auxiliary valve relative to the main valve to seat or unseat the former. Ducts c in the top piece lead from its outer surface to the central opening therein just above the valve-seat o as very clearly shown in Fig. 2. A piston f within, but not necessarilytightlyfittingthe chamber 0 is mounted on aspindle f, which passes loosely through the hub 12 and rests on the bottom of the valve-case A.

It will be obvious that the whole valve mechanism may be bodily inserted in or removedfrom the case A by removing the cap .A and that no. change is required in the usual valve-case to apply said mechanism thereto, and by removing the nut 17 a new valve-face b may readily replace an old or worn one without other disconnection of the Valve mechanism.

A pin 0 passes loosely Referring to Fig. 1, when the main valve is seated the fluid-pressure on the head of the stem at is equalized and the latter is practically balanced, because the opening in the auxiliary-valve seat e is of the diameter of the stem d, and the downward pressure upon the upper end of the head (1 is balanced by the fluid, which passes freely through the ducts c and acts upon the lower end of the head, so that the stem can be raised or lowered by only force enough to overcome friction in the stufling-box.

To open the main valve, the stem dis raised to unseat the auxiliary valve d and steam or other fluid passes by the ducts 0- through the valve-seat c into the chamber 0 above the piston f, which is stationary. This acts in a very large degree to balance the main valve, so that very little manual power is required to further lift the stem d, and with it the main valve, from its seat a, the fluid-pressure beneath the top piece 0 assisting, and the fluid then has free passage through the opening of the valve-seat a the friction on the stem 01 maintaining the valve open in the present instance of my invention.

In Fig. 2 the main valve is shown unseated, and in closing the valve downward pressure on the stem (1 sufficient to overcome friction thereon moves the main valve back to its seat, the movable parts being practically balanced, and when the main Valve is seated final inward movement of the stem at seats the auxiliary valve d as in Fig. 1, the fluidpressure in the caseat the inlet side retaining the main valve seated.

When the auxiliary valve is seated, communication between the chamber 0 and the inlet side of the valve-case A is cut off, and the auxiliary valve is maintained closed by friction.

I-Iaving shown one practical embodiment of my invention, which is not restricted to the precise construction and arrangement shown, what I claim, and desire to secure by Letters Patent, is-

1. An apparatus of the character specified, comprising a case or shell having a valve-seat therein, a cooperating main valve having a chamber, a stationary piston therein, and

manually-operated means to control communication between said chamber and the inlet side of the valve-seat, whereby the main valve may be partially balanced when it is to be unseated, substantially as described.

2. An apparatus of the character specified, comprising a case or shell having a valve-seat therein, a cooperating main valve having a chamber, a piston in said chamber, a spindle attached to the piston and extended through the bottom of said chamber and adapted to rest on the bottom of the valve-case, and

manually-operated means to control communication between the inlet side of the valveseat and the chamber above the piston, substantially as described 8. An apparatus of the character specified, comprising a case or shell having a valve-seat therein, a cooperating main valve consisting of anapertured disk having a removable annular face to cooperate with the valve-seat, an annular flange on said disk, and a top piece therefor, to form a chamber, a piston in the chamber, a spindle attached to the piston and extended loosely through the disk-aperture to rest on the valve-case, an auxiliary valve to control communication between the valve-case and the piston-chamber; the main and auxiliary valves being connected and having a limited relative movement, and a valve-stem to operate said valves, substantially as described.

4. In an apparatus of the character specified, a disk having oppositely-extended, annular flanges and a hollow, central hub extended from one side of the disk, an annular valve-face,a nut mounted on the hub to retain said face within one of said flanges, a top piece attached to the other flange and having a valve-seat, ducts in said top piece from its outer face to the valve-seat, and a controlling-valve to' cooperate with the seat and mounted to have a limited movement on said top piece, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FRANK A. LITTLE FIELD.

Witnesses:

JOHN C. EDWARDS, AUGUSTA E. DEAN.

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