US447523A

US447523A - Safety-valve

Info

Publication number: US447523A
Authority: US
Publication date: 1891-03-03
Anticipated expiration: 1908-03-03

Description

(No Model.)

I. P. KEARNS..

SAFETY VALVE.

No. 447,523. Patented Mar. s, 1891.

vthereof'.

UNTTED STATES PATENT EETCE.

ISAAC F. KEARNS, OF CHICAGO, ILLINOIS.

SAFETY-VALVE.

SPECIFICATION forming part of Letters Patent No. 447,523, dated March 3, 1891.

Application filed May 22, 1890.

To @ZZ whom t may concern:

Be it known that I, ISAAC F. KEARNs, a citizen of the United States, residing at Chicago, in the county of Cook and State of' Illinois, have invented a new and useful Improvement in Safety-Valves, of which the following is a specification.

My invention relates to a steam-valve of the class commonly called pop safety-valves.

The object of my invention is to simplify and render more eflicientvalves of this class; and to this end it consists in the construction hereinafter described, and pointed out in the claims.

In the drawings like letters refer to the same parts in the several figures, in which- Figure l is a side elevation of my valve. Fig. 2 is a vertical section of the same. Fig. 3 is a cross-section of' Fig. 2 on the line 3 3 Fig. 4 is a cross-section on the line 4 4 thereof. Fig. 5 is a side elevation, partly in section, of a modified form of valve-stem.

A designates the outer and main casing of the valve, which is constructed in the usual manner and has screwed to it the common form of dome B. This casing and domeinclose the working parts of the valve.

The valve proper I mark by the letter C, and it has the usual guiding-spider and general conformation, butits seating edge or rim is peculiar, and its special construction forms a part of mypresent invention. Around the seating-edge of such valve is a ring D, which is capable of vertical adjustment by reason of an internal screw-thread, which meshes with au external thread upon the upper portion of the valve-seat. The outer surface of this ring is provided with a series of teeth, and a pin or set-screw E passes through an aperture in the outer casing and enters the space between two of these teeth, so as to retain the ring in any position to which it may be adjusted. This adjustment of the ring determines the amount of steam which may be blown off, for when the valve is first lifted from its seat the steam enters the chamber between the ring and the edge of the valve, and if confined closely will exert an upward pressure and open the valve widely; but if by an adjustment of the ring the steam is allowed to escape more quickly its upward Serial No. 352,768. (No model.)

pressure upon the valve will not be so great, and hence such valve will not be lifted to such an extent.

The construction above described and the operation of the same are old, as are shown in the patent to Alexander Orme, No. 374,7 50, dated December 18, 1887, and I do not desire t0 herein cover the same; but I have devised a peculiar construction by means of which said operation is improved, and this I will now describe.

The inner surface of the ring just above the valve-seat inclines` inwardly for a short distance and then extends horizontally further outwardly to a point beyond the Vertical plane intersecting the outer edge of the top of the valve, and then projects vertically at right angles to such horizontal portion. Just beyond the seating-edge of the valve its periphery is concaved or recessed to about its upper edge. The ledge, or, rather, the angular recess, made in the inner surface of the valve-ring by the meeting of the horizontal and vertical cuts in suoli surface extends t0 a point beyond the outer upper edge of the valve, and this angular cut is designated by the letter A. It will thus be seen that when the steam begins to escape it may go as far as the outer upper edge of the valve, but at this point meets thc vert-ical Wall in the cut ofthe valve-ring and is deiiected or thrown backward against the under surface ofthe valve proper, and this exerts a considerable pressure upon such valve, and hence materially assists in lifting the same. It is to be observed that inasmuch as the cut in the valvering extends horizontally to a point beyond the outer upper edge of the valve quite a considerable amount of steam may flow into this cut and be deflected by the wall against the under side of the valve, whereas in previous constructions the wall of the valve-ring was placed so close to the valve-seat that but a small body of steam would be deflected against the under side of the valve.

The next portion of my invention relates to the arrangement of the spring. Heretofore a spiral spring has been arranged upon the upper portion of the valve, and the coils of such spring have been beveled upon their inner edges with a conical washer or inclined fol- IOO lower resting upon such bevel. It has been found in practice that under great pressure the follower or washer would act as a wedge in spreading apart the coils of the spring and so injure the efficiency of the latter. In my construction I bevel the outer surface of the upper and lower coils toward the outer edges of the same and correspondingly form the parts of the valve and of the adjusting-nut F. I have indicated the points where the spring II is beveled by the letter I). By this construction the spring under great strain is centered with respect to the valve, and its coilshaveno tendency to individually spread, but rather a tendency to coil closer than before. In the construction shown in Fig. 2 the lower bearing for the spring is formed by concaving the upper surface of an extension I, formed integrally with the valve. This extension has also a socket. for the valvestem K. It is obvious, however, that many changes or variations may be made in this part of the construction without departing from the principle of my invention. One of these modifications is shown in Fig. 5, which represents a side elevation, partly in section, of a modiiied form of valve stem with a bearing or seat for the spring cast integrally therewith. The nut F for adjusting the spring is of the usual construction, except that it has the concave bearing-surface for the beveled upper coil of the spring. It is manifest that the bevel of the coils and the con cavities of the bearings for such spring together form a kind of ball-an d-socket joint, which permits the spring to move upon its bearings and adjust itself in proper position with respect to the valve, even if it becomes temporarily displaced. In a recess cut through the side of the casing is pivoted a lever G, the purpose of which is to manually operate the valve. This lever has a simple and detachable connection with the casing, as is shown in Fig. 3 of the drawings. A pin M passes obliquely through a slot in the casing and through the opening in the lever into a screwsocket formed to receive it on the opposite ple and convenient arrangement of lever-con- It is obvious that other changes ncction.

than those mentioned may be made by any one skilled in the art without departing from the principle of my invention.

that I claim, and desire to secure by Letters Patent, is-

l. The combination of a valvecasing having a vertical slot therethrough and an oblique aperture therein extending from the outside of the casing on one side of the vertical slot to and into the wall of the other side of such slot, where it terminates in a socket, with a detachable valve-lifting lever having a hole normally in line with the aperture in the easing, and a securing-pin passed into and through the oblique aperture and hole and screwed into the socket, substantially as and for the purpose set forth.

2. The combination of a valve and a spring for forcing the same to its seat,the said spring having its upper and lower surfaces beveled outwardly, with bearing-surfaces inclined or concaved to adapt them to the spring, whereby a ball-andsocket connection is obtained, substantially as and for the purpose set forth.

3. The combination of a valve and a coiled spring for forcing the same to its seat, the upper and lower coils of which spring are bev eled outwardly, with bearing-surfaces inclined orconcaved to adapt them to the contour of the upper and lower coils of such spring, whereby a ball-and-socket connection is obtained between the spring and its bearings, substantially as and for the purpose set forth.

4. The combination of a valve having an upwardly-projecting neck which terminates in a disk concaved upon its remote side, an adj usting-nut having its inner surface concaved, and a coiled spring confined between such nut and disk and having its upper and lower coils beveled outwardly, substantially as and for the purpose set forth.

5. The combination of a safety-valve having its edge extending beyond its seating-su rface and recessed on the under side thereof, with an adjustable ring surrounding the edge of said valve and provided with an inner recessed surface extending laterally as far as the outer edge of the valve and bounded by an upright wall, whereby the ring may be adjusted above the outer edge of the valve, substantially as described.

ISAAC F. KEARNS. `Witnessesz F. SEARLE, THOMAS S. DONOVAN.

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