US591013A

US591013A - Safety-valve

Info

Publication number: US591013A
Authority: US
Publication date: 1897-10-05
Anticipated expiration: 1914-10-05

Description

(No Model.)

P; SGHREIDT.

SAFETY VALVE.

Patented Oct. 5,1897.

ms slams PETERS cn. #How-Lune., WASHINGTON, n c.

vadapted to the same form of valve.

Nrrnn STATES PATENT,

FFlCE SAFETY-VALVE.

SPECIFICATION forming part of Letters Patent No. 591,013, dated Octoloci` 5, 1897.

Application filed March 18, 1896. Serial No, 583,802. (No model.)

To all whom it may concern:

Be it known that I, FRANK Scnnninr, a citizen. of the United States, and a resident of Mansfield, in the county of Richland and State of Ohio, have invented certain new and useful Improvements in Safety-Valves, of which the following is a speciiication.

My invention is an improvement in safety and relief valves; and it consists in approved means by which the fiuid to be controlled is utilized to overcome the external force upon the pressure controlling the valve, whereby said valve will be rapidly thrown open torinsure a fre-e dischargeof the i'luid'under pressure and as rapidly closed when the excess of pressure is relieved. l

It also consists in certain details of construction by which the main objects of the invention are economically and with certainty attained, all of which will be first fully described in connection with' the accompanying drawings and then particularly referred to and pointed out in the claims.

Referring to the drawings, in which like parts are indicated by similar reference-letr ters wherever they occur throughout the various views, Figure l is a longitudinal central vertical sectional view of one form of my improved safety-valve. Fig. 2 is a top or plan view of the saine, a portion being broken away to more clearly indicate the means by which the spring-pressure of the su pplemental or trigger valve is locked. Fig. 3 is a transverse sectional view through line of Fig. 1, looking down upon the main-valve seat. Fig. 4: vis a similar view through the same line, showing another form of valve-seat Fig. 5 is a modified form of the device shown in the preceding figures and is my preferred form of valve for general purposes. i

Referring iirst to Figs. l to 4, inclusive, the valve case or housing properis composed of the cylindrical shell A, which has a lateral discharge-branch a. The lower end of this case A is screw-threaded to receive the member B, which has formed integral with, it the main-valve seat h' and a downwardly-projecting branch lg', which connects to the boiler or other vessel' containing the fluid under pressure. This part B is connected to the case A by screw-threaded connection, and the top of the'case A is closed by a cap AQ which is centrally perforated to pass the 'tubular stein C and has also projecting upwardly from it an arm a', which is perforated at its upper end to receive the pivot, which is the fulcrum of a testing-lever CL2, the bifurcated arms of which pass upon each side of the arm or stud a and under thehead'cl of the valve-stein d of the trigger-valve D. The head A' has also atubular extension ci?, which receives a screwthreaded set-pin a4, the shaft of which passes through one of a series of perforations a5 in the outwardly-projecting flange a of the cylinder A. The purpose of this arrangement is to adjust or regulate the tension of the spring E,\which is compressed between an adjustable plunger c and a piston c, formed in-` l tegral with the tubular stem C for the pur-` pose of regulating the pressure by which the main valve F is held to its seat l).

The ange c, in connection with the vsplit ring canda screw-threaded diskcz, forms a piston within the cylindrical shell A, the parts v being, when screwed together, practically integral with the cylinder or tube C' which houses a s` rin0` cl2 which is com ressed between the lower end lof the cylindrical stem C and the top of the valve D.

The cylinder C has a reduced lower end c3,

, which passes through the partition ci of the case' A and seats in the upper extended neck y f of the' main valve F, so that the pressure of thespring E forcibly holds the valve F to its seat. The valve F has also a tubular extension f, which passes through the valve-seat b andV extends down into the branch h'. The valve D has its seat at the lower and larger end of the cylinder C', and said cylinder has above the valve lateral perforations cdgwhich,

when the valve D is thrown up by pressure within the boiler or other vessel holding the compressed fluid, allows the fluid to pass into a chamber as and exert its pressure to throw up the cylinder C. The disk c2 has a series of vertical perforations c5, which admit the fluid under pressurebetween the flange c and disk c2, thus expanding the split packing-ring c and making a steam-tight joint between the piston and the cylindrical shell A.

The cylindrical stem C is grooved or corrugated externally, as clearly seen in Fig. 9, and the loweriend of the stem being screw- IOO threaded and tapped into the cylinder or housing C it is evident that the tension of the spring d2 may be regulated by screwing the tubular stem C into the end of the tube C or turning it backward to release the springs tension. By this means the valve D is adjusted to its seat with the desired pressure, and when properly adjusted the adjustment is held by a screw-threaded pin d2,tapped into a tubular extension alo upon the cap A. The point of the screw a9 entering one of the grooves in the tube C locks the adjustment.

The seat 19,4as seen in Figs. l and 3, has an annular groove b2 from the top down to the brackets b3, which support the center ring b4, which serves as a guide for the valve-stem f', while in Fig. 4 the valve-seat is provided with an annular series of perforations for the same purpose. The purpose of making the valve F and valve-seat larger than the unobstructed opening of the branch b is to insure a greater area for steam pressure through the series of perforations or through the annular groove b2 to the under side of the valve F to allow a free discharge of the fluid under pressure with a very limited upward vmovement of said Valve.

rlhe form shown in Fig. 5 differs from that shown in the preceding figures inthat the lower member of the caseB extends up above the discharge-branch d and is screwed onto the lowerend of the case A2. The main valve F in this View seats upon the upper portion of the branch b, in which it is guided by the wings b5, extending from the lower end ot' its stem. The lower end of the case A2 has a downwardly-cxtended screw-threaded neck to receive the packing-n ut auto form a steamtight joint around the stem c6 of the valveseat, the valve D' in this case being inverted and guided by wings extending up into the cylinder C.

In the form shown in Fig. l the diminished end csiits loose enough to allow steam or condensed water to escape from the chamber co8, but the stem in the form shown in Fig. 5,being packed b v the nut a, will not allow 'the steam or condensed water to escape, and in this case a small hole L12 is bored through the bottom of the cylinder A2, and there are also perforations @13 in the case A and A2 to permit any steam to escape which might leak into the upper part of said case from the chamber a8.

In operation the valve F is held by the spring E to its seat with slightly more pres sure than desired to relieve the boiler, while the trigger-valve D or D is set to the pressure desired. When this pressure is exceeded, the trigger-valve is thrown up against the pressure of its spring d2. The steam under pressure then entering the chamber as exerts its pressure to throw the stem C up against the pressure of its spring E, when the valve F will quickly open until the pressure is reduced. So soon as it is the spring cl2 will throw its Valve D toits seat, cutting off the pressure in the chamber as, when the force of the spring E will quickly close the valve upon its seat.

What I claim isl. The combination o'f the main-val ve chamber, the main valve having a tubular stem extending into the inlet-passage and a tubular extension upon the back of said valve having a valve-seat within it, a tubular stem having a reduced lower end to pass through the partition of the main-valve chamber, a seat within the upper tubular extension of the main valve the enlarged upperportion of said stem above the partition havinga valve in its lower end and a piston above the valve forming a pressure-chamber, a tubular follower screwed into said stem and forming an upper extension thereof, a spring compressed between said follower and said valve to hold it to its seat the tension of said spring being regulated by the follower, a spring to bear upon the piston of the tubular stern andhold the main valve to its seat, a follower above said spring in the upper end of the case, and the t op cap of the case havin ga screw-thread ed neck to engage the external thread in the upperend of the case and bear upon said follower, whereby the tension of the main-valve spring is regulated, substantially as shown and described.

2. The combination of the case having a main-valve chamber, a tubular extension screwed into the upper end of said valvechamber having its lower end perforated, and

a screw-threaded neck or extension surroundling said perforation, a tubular stem passing through said neck extending through the top of the case havinga valve-seat within it, and a piston carried by it to fit the tubular extension, the main valve centrally perforated and having an uppertubular extension to receive the diminished neck of the tu bularstem, a packing-n ut to make a steam-joint between the tubular extension of the case and the tu bular stem, a valve in said tubularstem having its stem extending outside of the tubular-stem, a spring to hold said valve to its seat, a spring bearing upon the piston of the tubular stem to hold the main valve to its seat, and means such as shown for regulating the tension of the valve-springs, substantially as shown and described.

FRANK SCHREIDT. itnessesr J. CLARKE CUsTER, LoUIs P. BENNETT.

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