US2480553A - Pressure operated switch - Google Patents

Description

1949- J. T. COOPER ET AL.

PRESSURE OPERATED SWITCH Filed April 30, 1945 INVENTOR.

Q9 J. T Coo oer JTL ATTOB EY Patented Aug. 30, 1949 2,480,553 rassscan cram-ran swr'ron James T. Cooper and James T. Logan, Atlanta, Ga., assignors to- General Electric Company, a corporation of New York Application April 30, 1945, Serial No. 591,100

4 Claims. 1

This invention relates to a circuit recloser, such as is employed to control the flow of current in electric power circuits, and particularly to devices for the automatic restoration of electric service to power circuits interrupted by temporary or transient disturbances on the line. A particular object of our invention is to provide a circuit recloser which shall be adapted to restore the flow of current in an electric power circuit following its interruption just long enough to allow the circuit to regain its electrical insulating characteristics after these have been temporarily destroyed as by lightning, or other causes.

A more specific object of our invention is to provide a service restorer which shall be operable independent of the magnitude of the current flowing through a fault in the circuit, but which shall employ abnormal currents lower in magnitude than necessary to operate conventional restorers or breakers to control an external source of energy capable of operating the circuit restorer in a predetermined manner.

A still more specific object of our invention is to provide a circuit recloser which shall employ an explosive, such as gun powder, as its external source of energy, and which shall be adapted to close a circuit repeatedly a predetermined number of times upon abnormal conditions occurring.

A still further object of our invention is to provide a circuit restorer employing an explosive as an external source of power for opening the circuit and which shall employ the explosive force to inject a deionizing agent into the path of the are formed incident to the breaking of the circult.

In accordance with our invention we provide a circuit restorer employing an explosive for opening the switch, which explosive shall be detonated responsive to an overload in the circuit controlled. A repeating mechanism is included in the apparatus for positioning another explosive charge each time the switch is opened. The

switch may be reclosed by energy stored up in a spring and will reclose immediately the opening force is released. If the fault or overload continues, the switch is repeatedly opened and a controllable pressure is built up in an auxiliary chamber by successive operations of the apparatus, which pressure is utilized to operate a lockout mechanism which locks the switch open until it is restored manually. A further feature of our invention comprises the injection of a deionizing agent into the are formed by the opening of the switch, which deionizing agent may be included in the explosive or in a separate vessel through Referring now to the drawing for a better un-' derstanding of our invention, we show an electric circuit embodying conductors I0 and II electrically connected to connectors I2 and I3 which lead to a switch having stationary contacts I6 and I! and a movable or bridging contact I8. 'For simplicity of illustration, only a single phase is shown but it will be apparent to those skilled in the art that the invention is applicable to multiphase circuits.

The switch just described is mounted in a cylinder I9 having a piston 2| therein connected to the bridging contact member I8 and having a piston rod 22 extending upwardly through the cylinder cover 23. The cylinder cover 23 is mounted on the cylinder I9 in a fluid tight manner, and a packing nut 24 insures a fluid tight fit between the piston rod 22 and the cover 23. A spring 26 is located in the cylinder I9 above the piston 2| and serves normally to hold the switch closed, that is with contacts I6 and I1 bridged by the member I8. The cylinder I9 is provided with an adjustable orifice valve 21 located above the piston 2|, when the switch is closed, which valve serves to release pressure from the cylinder after the piston 2I has moved upward a suilicient distance to open the switch.

The cylinder I9 is mounted on a base 28, which in turn may be supported from any suitable stationary support, such as a cross arm '29. The base 28 is formed of two parts held together by means of bolts 3| which define between them a magazine chamber 32 in which is located a magazine 33 mounted for rotation within the chamber about a pin 34. Also, the base 28 defines an explosion chamber 36 which communicates with the lower end of the cylinder I9 and with the magazine chamber 32. The magazine 33 is adapted to contain a plurality of cartridges 31, each containing an explosive and which are adapted to be positioned, one at a time, in communication with the explosion chamber 36. The magazine chamber 32, at one side, is provided with a removable cover 33 so that the cartridges 31 may be inserted in and replaced in the megazine.

anemone The cartridges 3'! are detonated, one at a time, by means of a firing pin 39 carried by a solenoid 4i. The windings 82:01 the solenoid are energized from a circuit 43 which in turn is energized from a transformer 64 upon an'overload, such as might be caused by lightning or by grounding of the power circuit illustrated by the conductors l and ii.

The magazine 33 is rotated step by step by means of a flexible wire 66 encased within a sheath t1 and connected at its upper end to a lever 48, which is pivoted intermediate its end at B9 to the'side of the cylinder cover 23 and which is connected at its other end by means of a slotted connection, to the upper end of the piston rod 22. Located within the magazine chamber 32, at one side thereof, is a guide 52 upon which is mounted a crosshead 53 carrying a pawl 54. The lower end of the wire 46 is connected to the crosshead 53 so that each time the piston 2| moves upwards, the wire 46 is forced downwards and inwards of the magazine chamber 32 and the pawl 54 engages a notch 56 in the magazine 33. Then when the spring 26 forces the piston 2i downwards, the wire 46 is pulled upward and outwards of the chamber 32 thereby rotating the magazine one step and placing another cartridge above the detonator 39. A spring latch 55 mounted in the side of the chamber 32 engages a notch 56 each time the magazine is rotated a step and holds it against accidental displacement.

At 51, on the piston rod 22, we provide a latchingnotch and mount on top of the piston cover 23 a latch 58 adapted to engage in the notch 57 and hold the piston 2! in its raised position with the switch open. The latch 58 is pressed towards the piston rod 22 by means of a spring 59. Connected to the cylinder i9, near the upper end thereof, is a relatively small auxiliary cylinder 6i. A passage 62 establishes communication between the cylinder l9 and the auxiliary cylinder 68 and has located therein a check valve 63. Located within the auxiliary cylinder 8! is a piston M which is biased upwardly by means of a spring 66. A piston rod 67 extends upwardly through the cover 68 of the cylinder BI and engages in a notch 69 of the latch 58, thereby holding it back out of the way of the piston rod 22. A packing nut 7i prevents leakage around the piston rod 61. Upon repeated operation of the piston 2i in opening the switch, pressure is built up in the auxiliary cylinder 6! and, when such pressure hecomes strong enough to overcome the spring 68 beneath the piston 68, the piston is forced downwardly, disengaging the rod 61 from the notch 69 and thereby allowing the spring 59 to force the latch 58 inwardly to engage the notch 57 on the sage 36 into the cylinder i9 and thereby aid in quenching the are formed by opening the switch. In order to further aid in quenching the arc, we may provide a deionizing agent in the cartridges 31 which will be volatilized by the heat of the explosion and carried with the explosive gases into the are. A number of such agents are known and have been employed in other ways, and we make no specific claim oi novelty to any particular such agent. We may also provide, alongside the cylinder is, a chamber I3 having a screen H vin the bottom thereof, which carries a suitable delonizing agent 16 above the screen. The chamber 13 is connected to the explosive chamber 36 by means of a conduit l1 and a conduit 18 leads from the upper part of the chamber, above the screen 14 to the cylinder i9 directly in front of the contacts I6 and i1, entering the cylinder at 19. With this arrangement, a part of the gases of explosion are shunted through the conduits I7 and 18, and chamber 73, carrying with them a part of the deionizi'ng agent, volatilized by the heat of the explosive gases, and blown directly into the path of the arc formed by opening the switch.

From the foregoing it will be apparent that we have devised an improved service restorer of 'the character described which utilizes the force of wardly through the explosion chamber, or pasan explosive as an external source of power for opening the switch, together with automatic means for closing the switch, and other means operable upon a predetermined number of successive openings of the switch to lock the switch in open position. It will furthermore be seen that we have utilized the explosive force, as well as the heat of explosion, to inject a deionizing agent into the are formed by opening the switch.

While we have shown our invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing from the spirit thereof, and we desire, therefore, that only such limitations shall be placed thereupon as are'speciflcally set forth in the appended claims.

What we claim is:

i. In apparatus of the character described, a switch, switch opening means comprising 8. cylinder, a piston in the cylinder operatively connected to the switch, an explosive charge disposed to create sudden pressure Within the cylinder to operate the piston and open the switch and to discharge the gases of explosion around the switch, a deionizing agent carried by the explosive charge, a spring-for closingthe switch, a pressure accumulator cylinder connected to the first mentioned cylinder and adapted to accumulate pressure responsive to successive operations of the piston, and means operable responsive to a predetermined pressure in the accumulator cylinder to lock the switch open.

2. In apparatus of the character described, an electric circuit, an operating cylinder, a switch controlling the circuit and disposed within the cylinder, 9, piston in the operating cylinder connected to the switch, a magazine, a plurality of explosive charges carried by the magazine, means responsive to an overload in the circuit for detonating an explosive charge, a spring acting against the piston for normally holding the switch in closed position, a latch for engaging the piston with the switch in open position, an accumulator cylinder, a piston'in the accumulator cylinder, a detent carried by the piston for normally holding the latch in disengaged position, and means responsive to successive operations of the operating cylinder in opening the switch to create pressure in the accumulator cylinder to release the latch, and means for adjusting the pressure accumulated in the accumulator cylinder.

3. In apparatus of the character described, an electric circuit, an operating cylinder, a switch controlling the circuit and disposed within the cylinder, a piston in the cylinder connected to the switch, an explosion chamber in communication with the cylinder, a magazine mounted for step by step rotation, a plurality of explosive charges carried by the magazine and adapted to be placed successively in communication with the explosion chamber, means responsive to an overload in the circuit for detonating an explosive charge and creating sudden pressure to be discharged into the cylinder around the switch to open it, a spring for closing the switch, mechanism operatively connected to the piston and adapted upon each closing of the switch to place another explosive charge in position to be detonated, adjustable means for accumulating pressure created by successive operations of the piston, and means operable upon the accumulation of a predetermined pressure for locking the switch in open position.

4. A circuit interrupter comprising a chamber, separable contacts disposed in said chamber, means for biasing aid contacts toward the closed position, piston means in said chamber for opening said contacts, pressure producing means including an explosive charge disposed to operate said piston and to discharge the ases of explosion around said contacts, said charge including as a portion thereof a deionizing agent which is volatilized by the heat of the explosion.

JAMES T. COOPER.

JAMES T. LOGAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 508,652 Thomson Nov. 14, 1893 723,183 Read Mar. 1'7, 1903 1,805,082 Edsall May 12, 1931 2,011,144 Coffman Aug. 13, 1935 2,049,328 Skeats July 28, 1936 FOREIGN PATENTS Number Country Date 390,317 Great Britain Apr. 6, 1933

Images