US978294A - Automatic cut-off valve. - Google Patents

Description

E'. HODGKINSON.

AUTOMATIC GUT-OPF VALVE.

APPLICATION FILED 00T. 8, 1909y Patented Dec. 13,1910.

2 SHEETS-SHEET 1.

F. HODGKINSON.

AUTOMATIC www VALVE.

APPLICATION FILED 00T. 8, 1909. I

Pate'ned Deo. 13, 1910.

2 SHEETS-SHEET 2.

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nnirnnsrnrns"PATENT onirica.

FRANCIS IEIODGKINSON,` OF EDGEWOD PARK, PENNSYLVANIA, ASSIGNOR T0 THE XVESTINGHOUSE MACHINE COMPANY,

A CORPORATION OF PENNSYLVANIA.

y Auronario your-oar VALVE.

Specication of Letters Patent. Patented Dec. 132111910.

Application filed October, 1909. Serial No. 521,743.

To all whom it may' concern:

Be it known that I; FRANCIS HoDeKIN'soN, a subject of 'the King ofGreat Britain and Ireland, and a resident of Edgewood Park, 1n the county of Allegheny and State Vof E Pennsylvania, have made a new and useful Invention in 'Automatic Gut-Off Valves, of which the followingis aspecification.A

` This invention relates to valves and particularly to automaticlcut-otl valves.

It is customary to provide engines and otherl fluid actuated motors with throttle valves,'whicl1` may be manually operated to control the supply of fluid to the engine orrthe motor and which will operate automatically to shut oli'l the fluid sup ly when* the portion 'of such avalve isusually fluid actuated and is controlled by a reliefvalve VwhichV is operatedby .a speed responsive're- Vliet" mechanism on .'.theengine. oi' motor.

The objection to such an arrangement 1s 'that theoperat-ion of readjusting vthe relief,

mechanism, opens the valve. This is objectionable for the reason that a careless operator might latch up the release-mechanism,

immediately afterl it has been automati- 'cally released and thus, fully opening the supply valve, immediately delivering a full supply of fluid' to thefengine. Such a -procedure might cause disastrous results-to the engine or to the apparatusdriven by. it.

An ohjeetof my invention, is. to producean automatiocut-oll valve with which' meansare employed for rendering the automatic relief mechanism ineffective for opening the salve immediately after the valve has been automatically closed.

A. further object is to produce an auto- -matic cut ofi' valve in which manually operated means are employed, in addition to the automatic means, for readjusting and opening theI valve after it has been automatically closed. f,

A :further object is to produce a combined manually operatedthrottle valve and an automatic cut olf valve.l t

These and other objects I attain by means of an apparatus 4embodying the features herein described and illustrated. n

ln the drawings.accompanying this application and forming a part thereof, I have illustrated avvalve embodying my invention, partially in elevation and partially in section. j

For convenience of illustration, the illustration is divided. into two parts so that Figurel represents the upper part, and Fig. Q the lower part ofthe valve,

I lhave'illustrated an embodiment vof my invention in connection with a cut-oil'A valve but with no idea-'of in any way limiting it to the detailsshow'n or its application ft'o throttle valves. .i

Referring to the. drawings: A throttle valve 3 is mounted within a casing 4 so that it seats on a diaphragm. 5 formed within the casing. A cylindrical4 piston 6 is formed -integrally.. with the valve 3' and operates within a cylindrical extension which may vhe securedto the top portion `fof the .valve casing L A pressure equali'zi'ng port 9, formed in the valve-disk 3, is controlled by a pilot valve 10 which is secured to the endV side of. the valvel 3 to 'the chamber 15V through a continuously opened passage 18. Limited amounts of fluid are admitted to the chamber 16 fromthe-easing 4c pastthe piston 6 and around the valve. stern 11, and between "it andapaclt-ing 17, which is mounted on the portion 8. Leakage steam from the chamber. 15, past the differential piston 14, also.

enters the chamber 16. The diiferential piston 14 is so located that the face of greater area is-exposed to the fluid pressure in the chamber 16 and the face of smaller area is exposed to the fluid pressure in the chamber 15, consequently when the pressures are equalin the two chambersv the eilort `of the fluid pressure in thechamber 16 to raise the piston and open the valves preponderates over the ellort of-the fluid in the chamber 15 to force. the. piston. down and close the valve.

engine or motor to which the val-ve supplies lluid has exceeded a determined speed.

This may be accomplished by providing a. valve (not shown) of suitable construction for controlling the flow of fluid through the passage 19 which is automatically actuated by a cut-ofi` governor on the engine or motor, to open the passage 19. Then the chamber 16 is exhausted the fluid pressure in the chamber 15 preponderates and forces the piston 14 downwardly to close the valve. I. provide a second passage 2O fon exhaust- 1110' tluid from the chamber 16 so that the va ve 3 cannot be opened by merely closing the passagel). The passage'20 is formedin the valve stem-11 and extends from the upper end of the stem to a point below the pisi ton 14- where 1t communicates with the chamber 1 6. The upper end of the passage is closed by a valve 2l which is located in a casing 22 secured to the. valve stem and which may be closed by a screw valve stem 23. The screw valve stem 23 is suitably mounted in brackets 24 formed on a housing 25`which is secured to the top of the cylindrical casing 12. A hand wheel 26 .is provided on the. stem 23 for raising and lower-I ing it. A collar 27- is provided on the lower end of the stem 23 and abuts against a cap 28, which inclosesa coil spring 29 andlpro-A jects downwardly into the casing 22 and is moved longitudinally along the casing within the limits of a' lost motion connect-ion 31.` .The spring 29 surrounds a plunger 32 and is mounted between the cap 28 and the collar .83, formed on the nlunger, so as to force the plunger down to c ose thevalve 21 when the cap 28 is forced down by the screw stem 23.

A tip 34, on the plunger 32, extends u wardly through the cap 28, so as to gui e the longitudinal motion of the plunger, and the stem 23 is recessed at 35 to recelve it.

When the passage 19 is opened the valve 3 is moved to the closed position by the pressure ofthev fluid in the chamber 15 and the cap 28, since it is carried by the valve stem 11, receclesfrom the collar 27 releasing the spring 29. After the plunger 32 has moved downward and eased the tension of spring 29, the valve V21 is weakened to the extent of being unable to resist pressure from the chamber 15. Thus, the automatic feature of the valve having once operated, itis impossible to open the valve without rst lowering the screw stem 23 so that the collar 27 abuts agalnst the cap 28 and, through the agency of the spring 29 and the plunger'32, holds the valve 21 closed and permits,4 pressure to n build up in the chamber 16. This pressure of course` will not build up until after the passage 19 i s closed. The screw stem 23 may then be raised and the valve 3 will follow it, the upward pressure exerted by the fluid in the chamber 16 being sufficient to hold the valve 21 closed. The screw stem 23 may be employed to control the operation of the valve 3 irrespective of the pressure in the chamber 16. That is the valve 3 may be moved to any intermediate position and may even be closed by the screw stem-23 against the pressure in the chamber 16.

The housing 25 incloses a piston 40 which with the housing performsthe function of a dash pot and cushions the downwardmotion ofthe valve 3.

A. packing 38 is locatedv between the chamber 16 and the dash pot and surrounds the smaller portion of the differential piston 14. This packing is employed to prevent the leakage of fluid from the chamber 15 into the dash pot 'below the piston 40.

The stem 23 might abut directly against theplunger 32 to close the valve 21, but the springand cap connection, which intervenes between the stem. 23 and the plunger 32, are employed because it is desirable for the valve 3 to seat against a solid support when the valve is opened so that it will not rattle'in the steam currents passing-through the casing 4.; With the spring and .cap ,connection as described, the disk 3 can seat -firmly against the upper portion of the valve casing 4 when the collar 27 abuts against stop 39 rovided for it anncarried by the brac et 2 4. Without the sprlgconnection,

` there would be danger of relieving the pressure on th valve 21 afterthe 'disk`" 3 was seated aglai st the cap portion 8 and s0 exhausting ithe fluid pressure from' the cham- A ber 15.

The pressure of the spring 29 against the valve`21 is, ofcourse, diminished after the valve.3 is seated on the top portion 8, but the.. arrangement is such that the stem 23 cannot be raised far enough to totallyue- 'lieve the valve 21 of the spring pressure and to permit it to open. In accordance with the provisions of the patent statutes I have described the principle of operation-of my inventionl together with the apparatus which I now consider to represent the best embodiment thereof, but. lI desire to have it understood that the apparatus shown is only illustrative and that the invention can. be carried out by other means.

W'hat I claim is:

1. In combination with a supply valve, a manually operated and fluid actuated means for closing said valve and means for rendering' the fluid actuated means incapable of opening said valves until said manually operated means is moved to the closed positi'on.

2.- In combination with a supply valve, a fluid actuated means for closing said valve., a fluid actuated means for opening said valve and manually operated means for convio means.

5.l A supply valve, an automatically controlled device for controlling. said valve,- means for manually closing said valve independently of said device and a valve for rendering said ldevice ineffective in opening said valve Without the coperation of said means. s

6. A supply valve,1aii automatically controlled device for controlling said valve,4 ineans for manually closing said valve independently of said device and a valve controlledb .said means for rendering said -de'- vice ine etive in opening said valve.

7. A supply valve, an automatically con-V trolled device'for controlling said valveY and armanually controlled vvalve for rendering said device eilective in o enng said valve.

8. A supply valve, a fliiid actuated piston for opening and closing said valve, an auto- .matically controlled passage and a manually controlled passage for exhausting the opening fluid Apressure from said piston.

9. A supply valve, a fluid actuated piston for opening the valve, an aiftomatically controlled passage and a manually coii'tiiledL passage for controlling'jhe openingv fluid pressure on said valve. i

10. A supply valve, a fluid 'actuated piston for opening said-supply' valve, an automatically controlled passage for controlling the opening fluidpressure on said piston andan inde ina ly ndent valve for controlling the openin fluid pressure on said piston. i

11. supply valve', a fluid 'actuated piston for o ning said valve, an .automatically contro led passage for controlling the open-- in fluid pressure on said'pist'on and a-inanoperated valve for controlling the opening fluid pressure on said piston.

1:2. A supply valve, a fluid actuated piston for controlling the operation of said valve, a chamber ex oscd to Huid pressure for actuating said piston to close said valve, a chainber exposed to fluid pressure for actuating said piston to'open said valve, an automatically controlled luid passa e for controlling the fluid pressure in' saig last mentioned chamber and a valve vfor controlling the' fluid pressure in said chamber. .i 13..A supply valve, fluid actuated pis- .'ron lfor controlling-the operation of said valve, a chamber exposed to fluid pressure for actuating saidpiston to close said valve,

a 'chamber exposed to fluid pressure for actuating said piston toppen said valve, an auto-- inatically controlled'luid passage for con ltrolling the fluid pressure in said last inentioned chamber and manually actuated means for closing said valves independently of said piston and for controlling'the operation ofsaid piston. 1

14:. A fluid supply valve, a fluid actuated piston for controlling the operation of said valve, a chamber exposed to fluid pressure for actuating said piston. to open said valve,

an automatically controlled fluid passage for controlling the Huid pressure in said cliam.

ber, and a control valve for controlling the fluid pressure in said chamber and manually/'actuated means for closing-said control valves and for closin'g said sup ly valve'independently of the operation o said' piston.

l5. A supply Valve, a fluid. actuated piston for opening and closing said valve, an automatically controlled passage for exhausting the opening pressure from said piston, a second 'passage for exhausting. the

opening1 pressure from said piston and a manna controlled valve controllingl 'th'e flow of fluid through said second passage and a spring andlost motion connection for controlling the operation of said manually controlled valve.-

- 16. A supply valve, a fluid actuated piston `for opening and closing said valve, an automatically controlled passage and a inanually contro led passage for exhausting the opening pressure from said piston, a valve controlling the delivery of fluid through said manually controlled passage, n-.eans for closing said valve and a lost :notion and'spring connection between said closing means and -said valve.

17. A pupply. valve, a fluid actuated piston for o ening said'valve, an automatically controllapassage and a manually con 'trolled passage for controlling the opening pressure on said valvea a manually actuated valve for controlling the flow of fluid through said manually controlled passage-, means for closing said valve and a spring between said means and said manually controlled valve.

In testimony whereof, .I have hereunto subscribed my name this 5th day of October, 1909. .i

FRANCIS HODGKINSGN.

Witnesses:

C. W. MCGHEE, C. 'W. BALLAY.

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