US113810A - Improvement in steam-engine valves - Google Patents

Description

idniir %tair5 @anni Ctifitt Letters Patent No. 113,810, dated April 18, 1871.

IMPROVEMENT IN STEAM-ENGINE VALVES.

The Schedule referred to in these Letters Patent and making paxt of the same.

To all 4"persons to whom these presents may come Be it known that 1, NATHAN PAGE STEVENS, of Hopkinton, of the county of Merrimac, of the State of New Hampshire, have invented a new and useful Improvement in Steam -Engine Valves and their Chests; and do hereby declare the same to be fully described in the following specification and represented in the accompanying drawing, of whichlFigures 1 and 2'are vertical sections, taken in planes at right angles to leach other, of my improved valve and its chest as applied to the cylinder of an engine.

Figure 3 is an under-side view of the valve.

Figure 4 is a top view ofthe valve-seat or the baseplates of the valve-chest.

The valve-chest A is made ,open at one or both opposite ends in manner so that the valve B may be introduced into and drawn out ofthe chest through the open end, the said valve being hat on its upper and lower faces, and the two being parallel.

The-chest A is surmounted with a hollow dome, C, to open into it and to receive the steam through an induct, D, leading into such dome.

Encircling the hase ot' the dome is a groove, a, made lin the upper plate or top of the chest, such groove being arranged in manner as represented in figs. l and 2.

Within this groove is an annulus or ring-packing,

when necessary, without requiring any part or fixture c, of metal or other suitable material.

Furthermore, through the base-plate or valve-seat d of the chest are two parts, ee, to lead to the opposite ends of the cylinders.

Besides4 these parts there are two other openings, ff, .madedown through such base-plate and into a common Aexhaust-passage, g, the disposition or arrangement ofsuch openings f f relatively to the parts e e being shown in iig. 4. l

'lhe 'valve B is a block of metal having its opposite upper and lower surfaces parallel.

The valvel has formed in it a receiving-chamber or space, h, and an encompassing channel or groove i, suclr chamber and grooveopeningthrough the base or lower face of the valve.

The chamber also has an opening, la, leading out of its top, all being arranged in manner as shown in the drawing,the valve-stem t being pivoted, or hinged, or otherwise properly fixed to the valve.

With the valve and chest so constructedV steam, after entering the dome C, passes down through the valve-opening k into the receiving-chamber Il..

During the reciprocating movements of thevalve within its chest such chamber h will belmovedl alternately over the parts e e, each of which will be closedl by the valve while the other is open to the chamber.

Those portions of the valve which are to operate to close and open the parts ee are shown at m m.

While one of such parts m covers one part, the other part will'be luncovered and in free communication with the passage or chamber i, the same being so as to cause the exhaust steam to pass into such channel, and from thence through the openings f j, and into the common escape-passage y.

I would remark that only one opening, f, into the exhaust-passage g is requisite, although it is better to have two, because they relieve the valve ot' ,the steam quicker and more evenly than one part only would.

It will be observed that in the said valve and chest the induction of the steam is through the valve, whereas in most if not all other slide lvalves'the eduction takes place through them. V

Some-of the advantages incident to my construction of valve and chest are as follows:

First, the valve is substantially a balanced valve.

Second, in case of leakage of steam from beneath the valve and its seat such waste of steam, instead of blowing out the side of the valve-chest, will pass directly into the channel fi, from' whence it will ilow into the exhaust-passage. v

Third, the valve can be removed from the chest,

of the chest to be previously removed from` the rest.

Fourth, no stuffing-box to the valve-stem becomes necessary.

Fifth, the packing-ring over the valve will, by, the steam that enters the groove for receiving such ring, be forced down upon the valve so as to produce a steamtight joint around the valve induction opening.

If desirable, there may be a passage leading into the packing-ring groove in order to render certain the ent-rance oi' the -steam therein.

i make no claim to a packing-ring and groove in the abstract, or as ordinarily applied and used.

I claim as my invention the following, viz:

'lhe valve as made, with the receiving-chamber h open at top and bottom, and with the encompassing exhaust-channel i, iu combination with the main parts e e and the lateral exhaust-passage or passages f, all arranged in or with respect to the chest in manner and to operate as specified.

NATHAN PAGE STEVENS.

XVitnesses:

R. H. EDDY, J. 1t. Snow.

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