US1511143A - Safety valve - Google Patents

Description

7 J. C. SULLIVAN SAFETY YALVE Filed April 11, 1921 2 Sheets-Sheet. 1

Z- v 18 Z 16' UH HUGH I If. 11 6 21 6 2 25 20 Z? 5 III; 26 2 1.9

Qwmmtoz 1/71/2714" zwu/wm m1, I v I 60:47am

J. C. SULLIVAN Oct. 7 i924.

SAFETY VALVE Filed April 11. 1921 2 sheets-sham -4 r 36 ,g V

Patented Oct. 'Z, 1924.

UNITED E'S P A T ETN *QlFiFiIzCE JULIUS C. SULLIVAN, OETWARREN, PENNSYLVANIA.

Application filediApril "11, 1921.

which the .following is: aspecification;

My invention relates tosa'tety valves and particularly to safety valves especially designed tor usein conjunction witlrtank cars,

steamship tankers, or any such containers for; quantities of volatile liquid.

Storage and .sshipping' i tanks for volatile liquids-are frequently subj cted to high yinternal pressure due to the yolatilization -.ot', the l quid under varying{atmospheric cond1-. tion-s, and ll ISBSSQllt-ltlz tllflt tlllS pressurehe relieved hefor-e reachinga-sufficient degree-to rupture'or hurstithe tank. Also,-.when such tanks, .p articularly itank :qzars, are involved in" accidents, the vola'ti-lization; of the liquid is frequently rapid -with a. consequent rapid rise in the -.pressure within the tank. alt-is essentialatz such times that thegases-be permitted to escape and at the same time-flames be prevented from entering thetank, should the :gases {become ignited. Also, gases Lescapingit-rom such cars; are frequently ignited when the cars are adjacent-a locomotiveas frequently happens in switching :cars in the railroad yards and means should be provided to prevent the flames tromentering the tank.

The ohjectof my invention'is to -provide tlzSZLfBtYYiLlVG witlrmeans which will-permit escape of the gases after they have reached a predeterminedv pressure. rte furtherv and particularobject ot-myinvention is to provide a'deviee of; this character, which will permit of the escaping of the gases. only after the same .shall have reached a predetermined popp ng pressure, .to the end that a cont1nuous or prolonged discharge of small-quan'tities o:t .;gas shall be avoided. vA furtherobj ect. of my invention .is to provide a device as mentioned in which the valve will quickly andsecurely close .as soon as-the pressureis reduced below the ,predetermined popping pressure. Afurther ob ect otmy invention is to, provide means .for qu ckly extlnguishing-any. flames asthe .valve is closed. .A turther object ofmy invention istoprovi de a device .of the ,character mentioned which may be readilyiadjnsted to operate under. the desired pressure. A 'furtheuobject otmy invention isto provide. a device of the char- Serial 'No. 460,222.

acter underconsidei ationiof such construction that the escaping gases, under-pressure, shall he directedto a central. vertical-axis above'the-v-alve casing. A further object of my invention is to provide a safety valveas mentioned of such construction that the .variousparts and mechanismsshall present a minimum amount of obstruction to the I escaping gases. Further objects of my invention are-to provide a 'deviceas mentioned which will be of simple construction, which will not readily .get out of order and in which the variouselements may he'readily adjustechrepaired or replaced. "Other objects will appear hereinafter.

lViththese objects in view my invention consistsgenerally in a'valve casingand main valve in combination with. means for locking said valve in closed positionuntil the vapors have reachedapredetermined.pressure. "My invention further consistsin a device as mentioned in combination with.means for initially actuating the locking mechanism means for automatically extinguishing the flames should the escaping vapors become ignited. More specifically, said flame eatinguishing means-comprises a shutter or shutters adapted toautomatically closesaidcasing'as'the valve closes to exclude air from adjacentthe latter. Myinvention consists in various details of construction and arrangements ofpartsall as will be fully describedhereinat't-erand particularlypointed out in. the claims.

My invention will hemore readily under stood by reference to the accompanying drawings forming a part of this specification and in which Fig. 1 isa.sideelevation,.partiallyinsection, of asafetyvalve embodying my ,in-

vention, parts being shown .in. elevation, 'Fig. 2 is a top gplan View of the device, ;Fig.-3-is.abottomplanview, Fig. 4 is .a vertical section on {the .line 4-tof Fig 1, and, g Fig. 5 is-a transverse section on substant-ially the-1ine5?5 of Fig. 4:.

Referring now to the drawings, 1 indi cates the housing which comprises a lower cylindrical intake chamber portion 2 and an upper discharge portion 3. The exterior of the housing, intermediate the portions 1 and 2, is threaded asat 4 for securing the device in position in the usual manner, as illustrated in Fig. 4. The upper portion 3 is provided with means 5 for engagement with a wrench, for securing the device in position, or removing the same. The portion 2 is provided with inlet apertures 6 in its walls to facilitate the free passage of gases.

Between the chambers 2 and 3 is an annular valve seat 7. This is preferably removable so that the same may be readily repaired or replaced in case of wear. 8 indicates the valve which normally rests on the seat 7. This is provided with a depending hollow stem 9 which constitutes a timing valve barrel as will appear hereinafter. The valve 8 and valve seat 7 are preferably made of non-corrosive metal. Supported within the chamber 2 by arms 10 is a sleeve 11 which serves as a guide for the barrel 9.

12 indicates a bushing threaded into the upper end of the barrel 9, and 13 indicates a lock nut for securing the same in adjusted position. Extending through the bushing 12 and barrel 9 is a valve stem 14 terminating at its lower end in a squared head 15. The upper end of the stem 14 is threaded, and threaded thereon is a sleeve 16 held in adjusted position by a lock nut 17. The sleeve 16 carries a laterally extending flange 18 at its upper end for a purpose hereinafter described.

From the construction so far described, it is obvious that the valve 8is subjected to the pressure within the tank or reservoir, and as one of the primary objects of my invention is to prevent the valvefrom permitting escape of gases until the pressure has reached a predetermined popping. pres sure, means must be provided for normally locking the valve on its seat. To this end, I provide a transverse member 19 at,

the bottom of the chamber 2 which rests upon the head 15 and normally held in depressed position by a pair of pivoted arms 20. The arms 20 are pivoted between the arms 10, as on pins 21, and carry at their lower ends anti-friction rollers 22 which engage the member 19. These arms are normally pressed inwardly by springs 23 having seats 24 in the walls of the housings and seats 25 in the arms, as illustrated clearly in Fig. 4. The member 19 is vertically movable with the valve 8 and the ends of said member and the housing are provided with co-operating guiding means. For this purpose, I provide the housing with vertically disposed ribs 26 and notch the ends of the member 19, as at 27, to receive them. The

lower face of the member 19 is provided with a socket 28 to receivethe head 15 of the valve stem and to prevent the same from turning. The upper face of the member 19 is formed with a fiat centrally disposed portion 29 upon which the rollers 22 normally rest, and outwardly and downwardly curved portions 30 which constitute cam faces for co-operation with the rollers 22. I

As the arms 20 securely lock the valve in closedposition, means must be provided for tripping or initially moving the locking mechanism above described, when the pres sure has reached the predetermined point, in order to permit the valve to open. this end, a timing piston is arranged within the barrel 9 and equipped with means for moving the rollers 22 from the flat face or shoulder 29 of the member 19 on to the cam faces 30. 31 indicates a sleeve freely slid-- able on the stem 14 and terminating in a conical lower end 32 which rests on the face 29 of the member 19 and which is normally engaged by the rollers 22. On the upper end of the sleeve 31 is formed the timing piston which comprises a cup washer 33 and a packing expander ring 34, threaded upon the upper end of 31. Interposed between the ring 34 and the bushing 12 is a spring 35. 31 indicates a packing ring secured in a recess in the bottom of the portion 32 and surrounding the stem 14 to prevent the gases from following up the valve stem into the barrel 9. I

The operation of the portions of the device so far described is as follows: Normally the parts are in the positions indicated in full lines in Fig. 4 of the drawing. It will be noted that at this time the. rollers 22 rest upon the fiat face or shoulder 29 of the member 19 which prevents upward movement of the member 19 and therefore of the valve 8. When predetermined popping pressure has been reached the pressure of the gases on the timing piston 33-34 forces said valve upwardly against the tension of the spring 35. The upward movement of the timing piston raises the conical portion 32 of the member 31, thereby forcing the rollers 22 off of the shoulder 29 and on to the cam faces 30. The pressure on the under face of the valve 8 then raises the valve, and the valve in raising, lifts the member 19, the cam faces 30 thereof forcing the arms 22 outwardly into the position shown in dotted lines in Fig. 4. These arms, and the member 19, obviously limit the upward movement of the valve 8. It is obvious that the popping pressure may be regulated by adjustment of the bushing 12, thereby more or less compressing the spring As soon as the pressure is reduced below popping pressure, the springs 23 force the arms 20 inwardly, thereby depressing the member 19 and seating the \valve *3. The :=rolle1s1.=22, 'ritlingiupon the should-er '29, again zlockithe valveiagainst operation until :the popping pressure is again reached.

W'hen gases escaping Ifrom man i orifice rare ignited, ith-e i'clistancelof the vfl-ame from the orifice .is dependent upon 'the force of the gases at the orifice; that is, if the gases-rare escaping slowly and without muchxpressure, they burn close to the orifice, but if the gases are being ejectedunder,greatipressure, consequently with great velocity, they burn only at a distance from the orifice where the velocity becomes lessened. Itis-iobvi'ous therefore, that by permitting ithe :gases to escape only at considerable pressure, and avoiding leakage of gas in small quantities, the likelihood of the gases adjacent the valve becoming ignited is reduced to a minimum. To maintain the escaping gases concentrated and at the greatest velocity, I shape the portion 3 so that the escaping gases shall be directed to a central vertical axis above the valve casing. To this end, the walls of the portion 3 converge inwardly as shown clearly in the several figures of the drawing, thereby serving as a nozzle for concentrating escaping gases into a vertical columnunder high pressure. However, when the valve closes, the flame from ignited gases, may follow the gas to the valve, and one of the objects of my invention is to equip the device with means for extinguishing any such flames adjacent the valve. To this end, the discharge opening or mouth of the portion 3 is provided with means for cutting off air from the valve, and this means preferably comprises a hinged or pivoted closure. As illustrated in the drawing, I have provided the device with a pair of closure members pivoted on substantially parallel axes. 36 indicate the closures which are pivotally mounted upon trunnions 37 supported in upwardly extending lugs 38 on the housing 1. Each of the closures is provided with 2. depending member 39 which is notched to receive the flange 18. It is obvious that the member 16 moves upwardly with the valve 8, and with the construction shown, opens closures 36, as shown in dotted lines lines in Fig. 4. It will be noted that when the closures 36 are opened, they are inclined upwardly and inwardly, so as to assist the tapered end of the portion 3 in directing the gases centrally above the casing. As the valve 8 drops upon its seat, the flange 18, engaging the members 39, quickly closes the mouth of the housing by means of the closures 36, thus extinguishing any flame that might have followed the gases to the valve as the latter closed.

It will thus be seen that the device above described effectually prevents the contents of the container from being ignited from the discharge of :the gases through the valve, First, the gases are only discharged when under considerable pressure,-s0 that should they become ignited the flame will be maintained ataa safe: distance from the valve, and second, should theiflame follow theegas as the valve is 1 closed, the I closure -members 36 will quickly extinguish the flame.

While =Ihave described my invention for use iii-conjunction with tanks or reservoirs for volatile :liquids, it is obvious that the same maybe effectually used as a safety valve for steam boilers, compressed air tanks, or in :anysituation where it is-essentlfllEtO provide a safety valve for relieving internal;pressure after a predetermined pressure has been reached.

I claim 1. A device of the class described, comprising a housing, a valve therein, a cam surface and shoulder carried by said valve, a pivoted arm on said housing, a roller on said arm normally engaging said shoulder to lock the valve in closed position, and pressure actuated means adapted to move said roller from said shoulder to said cam surface to unlock the valve, substantially as described.

2. A device as set forth in claim 1 in combination with a spring forcing said arm towards said shoulder as and for the purpose specified.

3. A device of the class described comprising a housing, a main valve therein, a timing piston barrel carried by said main valve, a timing piston therein, a shoulder and cam surface movable with said piston, a pivoted arm provided with a roller normally engaging said shoulder for locking the main Valve in closed position, and means carried by said timing piston for moving said roller from said shoulder to said cam surface, substan tially as described.

4. A device as set forth in claim 3, further characterized by a bushing threaded into said timing piston barrel and a spring interposed between said bushing and said timing piston, substantially as described.

5. In a device of the class described, a housing, a main valve therein, a timing piston barrel carried by said main valve, a stem extending through said barrel, a member carried by said stem and provided with a shoulder and cam face, a pivoted arm on the housing provided with a roller normally engaging said shoulder, a sleeve slidable on said stem, a timing piston on one end of said sleeve and within said barrel, and means on the opposite end of said sleeve for moving said roller from said shoulder to said cam surface, substantially as described.

6. A device as set forth in claim 5 in combination with a spring forcing said arm and roller towards said shoulder, substantially as described.

7. A device as set forth in claim 5 in combination with a bushing threaded into said barrel and a spring interposed between said bushing and the timing piston, substantially as described.

8. A device of the class described, comprising a housing, a valve seat dividing said housing into inlet and discharge portions a main valve normally resting on said seat, a timing piston barrel depending from said valve, a stem extending through said barrel and projecting below the same, a transverse member carried by the lower end of said stem and provided with a shoulder and cam surfaces, a pair of arms pivotally mounted within said housing, and provided with rollers engaging said shoulder, a timing piston within'said barrel, means carried by the timing piston for moving said rollers from said shoulder to said cam surfaces, springs forcing said arms towards said shoulders, a bushing threaded into said barrel and a spring interposed between said bushing and said timing piston, substantially as described.

In testimony whereof I have signed my 1.

name to this specification in the JULIUS o. SULLIVAN. .Witnesses Rosn H. DAVIS, R. M. KREBS.

Images