US1236674A - Circuit-interrupter. - Google Patents

Description

L. W. CHUBB.

C1RCUITINTERRUPTER. APPLICATION FILED 0Ec.26.'191a.

1,236,674. Patented Aug. 14, 1917.

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WITNESSES: INVENTOR W 4 BY WM UNITED STATES PATENT OFFICE.

LEWIS W. CHUBB, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVAN IA.

CIRCUIT-INTEBRUPTEB.

Specification of Letters Patent.

Patented Aug. 14:, 1917.

To all whom it may concern:

Be it known that I, Lnwrs W. CHUBB, a citizen of the United States, and a resident of Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Circuit-Interrupters, of which the following is a specification.

My invention relates to circuit interrupting devices and particularly to devices for preventing disturbances in the interrupted circuits when the interruptions are effected.

Difficulties have been experienced in interrupting electrical circuits because of the burning of the contact members by the elec-' trical arcs that are set up in the circuit. Also, since the voltage surges are apparent at the instant the arc is extinguished, by reason of the inductance and the magnetic energy that is stored in the circuit, the arc may be reestablished and the above mentioned disturbances repeated because of the rise in the voltage being more rapid than the breakdown value of the gap between the disengaging contact members.

To overcome the hereinbefore mentioned difficulties, I provide a device that opens the circuit quickly by hydrostatic means and which directs a stream of cold oil or other insulating fluid between the contact members of the interrupter to force the arc outwardly and to prevent a striking back of the arc in case of relatively slow separation. I also provide electrolytic valve cells for preventing the voltage from surging and for constituting lightning arresters for the re spective circuits.

The single figure of the accompanying drawing is a diagrammatic view of circuits and apparatus embodying my invention.

Referring to the drawing, my invention is used to open the circuit through a conductor 1 which is protected by a plurality of electrolytic lightning arresters 2 and 3 disposed at the sides of a circuit interrupter 4:. The circuit interrupter 4 comprises a receptacle or tank 5 containing oil 7 in which is im mersed a stationary hollow contact member 6 flared out at its lower end, substantially as shown, and a movable contact member 8 which is normally held in engagement with the said flared end by a helical spring 9. Within the hollow contact member 6 is a tightly fitting piston 10 having a knob 11 on i s upper end again t which rests he ical spring 12 for returning the same to its normal position after it has operated to disengage the contact members. To the lower side of the receptacle 5 is attached a bracket 13 upon which is pivotally mounted a latch i l for engaging a projection 15 of insulating material on the movable contact member 8 and to which is also attached a lower bearing member 16. The lower end of the member 8 is slidably mounted in the lower bearing 16, as is also the upper end of a member 8 which is formed of some insulating material. The member 8* has attached thereto, at its lower end, two movable arms 17 and 18 of horn gap disconnecting switches 19 and 20, respectively. A conducting member 8 is attached, at its upper end, to the horn gap arms 17 and 18 and has attached thereto, at its lower end, one arm 21 of a horn gap switch 22 the other member 23 of which is grounded. A spring 24;, supported by a suitable stationary member 25 at one end and bearing against the horn gap arms 17 and 18 at the other end, maintains the switches 19 and 20 in closed position while the circuit interrupter 4 is closed, as hereinafter explained.

The electrolytic lightning arresters 2 and 3, which are ordinarily provided for protecting the circuit or apparatus from lightning discharges or similar phenomena, are connected severally, through the upper terminals of the same, to the conductors 1 on each side of the interrupter at and, through the lower terminals, to the arms 26 and 27 respectively, of the horn gap disconnecting switches 19 and 20.

Assuming that the apparatus and circuits are connected as shown in the drawing and that it is desired to interrupt the circuit through the conductor 1, the operation is as follows:

The piston 10 is depressed quickly to force the oil out of the stationary contact member 6 and thus efl'ect downward movement of the contact member 8 away from the flared end of the member 6. The cool oil that is thus forced downwardly by the piston 10 plays over the contact surfaces of the contact members 6 and 8, to cool the same. The contact member 8 is moved downwardly a sufiicient distance to allow the arc to be extinguished by the oil and to effect engagement between the lower end thereof and the member 8 and cause the latter to open the horn gap switches 19 and-20 and close the horn gap switch 22. When the movement just described is effected the latch 1 L engages the projection to retain the circuit interrupter 4 in its open position.

The lightning arresters or electrolytic valves 2 and, 3 are normally connected in series with each other around the circuit interrupter and each is connected to ground through the horn gap switch 22. Thus, any surges or other disturbances that occur on the line 1 when the interrupter is closed will be dissipated by the arresters 2 and 3. Since the arresters 2 and 3 remain connected in series for a predetermined time after the contact members 6 and 8 aredisengaged and,

since the gap between the horn members 21 and 23 of the horn gap switch 22 is relatively shorter than the gap between the members 6 and 8, if sufiicient voltage is impressed across the contact members by reason ot'the rise in voltage being more rapid than the breakdown value of the gap vbetween the disengaging contacts, the valves or arresters 2 and 3 will check the iiow of energy until the critical voltage is reached and then they will discharge through the gap 22 to ground. It will be understood that the time interval between the disengaging of the contact members 6 and S and the engaging of the horn gap members 21 and 2,3 is sufficient to permit the surge to be either absorbed or discharged to ground. Thus, adequate protection for the contact members is insured.

VYhen the circuit interrupter is in its full open position, the normal connection of the arresters. 2 and 3 is such that there is one arrester connected from each side of the line to the ground through a horn gap. Thus, any lightning discharges on either side of the interrupter will be absorbed or discharged to ground in the usual manner.

In order tov complete a circuit through the conductor 1, the latch 14 is withdrawn and the expansion of the springs 9 and 24 moves the movable contact member 8 upwardly until it engagesthe Stationary contact member 6. This movement opens the horn gap switch 22 and closes the switches 1.9 and 20, thus restoring the lightning arresters to their normal operating relations as will be read.- ily seen.

The chief advant-i gesof my invention are h ut i atiqn of he. n c sa y g nin resters for fulfilling a double purpose; namely, as lightning arresters and as surge protecting devices, and the providing of a hydrostatically operated circuit interrupter and cooling medium. lVhen the circuit interrupter is in its normal open circuit position, the gap between the horn gapmembers 21 and 23 is closed and gaps (not shownlof qual ength are re te tw en. th meme 96 1 17 a d fi lldl 4 127 espectively.

There is also an intervening space created between the contact members 6 and 8 when they are normally out of engagement.

Since the gaps which arecreated between the arms of the horn gap switches 19 .and 20 when the circuit breaker is opened are shorter than the gap or intervening spaces between-the contact members 6 and 8, as soon as the voltage rises to the critical value for the electrolytic devices, it discharges to the ground through oneof the horn gaps 19, 20 and 22, depending upon which .one is in its operative ,position, and thus extinguishes .the arc.

Th n rgy that .traversestheconductor 1 tends .to charge thearresters. and, when :the critical voltage value of the particular type of arrester is reached, the energy will .beconducted {to ground. The horn gaps are merely utilized to extinguish the arc :by lengthening the same in a manner familiar .to .those versed in the art. However, anyof the-other well known means may be employed equally as well to extinguish the arcs thus constituted.

It will be understood that the electrolytic a rrcstersuor valves 2 and :3 protect the line from surges. or lightning discharges as well as to -prevent the striking backof an arc in a switch by reason of the energy surge that usually follows the interrupting .ot a loaded circuit.

Electrolytic lightning arresters which are ordinarily used in combination with. circuit interrupters for lightning protection may be so arranged as to embody my invention and thus serve the double purpose as hereinhefore explained,

lVhile I have described my invention with reference to certain definite constru tion and operation, I desire it to be understood that changes may be made therein with respect to operating mechanism and structural refinements which not depart from the scope and. purpose of the same asset, forth in the appended claims.

I claim as my invention:

1. In an electric circuit, the combination with a circuit interrupter,v of electrolytic lightning arresters, .a discharge gap, and means for connecting the said lightning arresters across the terminals of. the circuit interrupter for a. predetermined time after the interrupter is opened and at all times through the discharge gap to the ground.

2. In. an electric circuit, the combination with a circuit interrupter, of a. plurality of electrolytic, lightning arresters normally connected in series acrosssthe terminals of the circuit. interrupter,.discharge gaps, and means for disengaging the series connection of the said arresters a predetermined time after the interrupter is opened and for connectingthe arrestersthrough the gapsto the gr und.

3. In an electric circuit, the combination with a circuit interrupter, of discharge gaps, an electrolytic valve comprising a plurality of lightning arresters normally connected across the terminals of the interrupter and cooperating with the gaps to protect the said circuit from lightning discharges, and means for connecting the electrolytic valve through the gaps to ground after the interrupter is opened to prevent the striking back of an interrupted arc therein.

4. In an electric circuit, the combination with a circuit interrupter, of an electrolytic "alve connected across the terminals of the circuit interrupter, a discharge gap, and means for disconnecting the valve from across the terminals of the circuit interrupter and to connect it between one terminal of the circuit interrupter through the discharge gap to the ground a predetermined time after the interrupter is opened.

5. In an electric circuit, the combination with a circuit interrupter, of a discharge gap, a plurality of electrolytic valves nor mally connected across the terminals of the interrupter and adapted to cooperate with the gap to protect the said circuit from lightning discharges, and means for so connecting the said valves after the interrupter is opened that the striking back of an interrupted arc in the circuit interrupter is preeluded.

6. In an electric circuit, the combination with means for interrupting the circuit, of electrolytic means for preventing the reestablishing of an arc after the circuit has been interrupted, and a discharge gap adapted to cooperate with the said electrolytic means to protect the said circuit from lightning discharges.

7. In an electric circuit, the combination with a circuit interrupter, of a plurality of electrolytic lightning arresters connected in series across the terminals of the interrupter, a discharge gap connected from the common terminals of the electrolytic arresters to ground, two auxiliary discharge gaps, and means for connecting the arresters from the terminals of the interrupter through the respective auxiliary discharge gaps to ground a predetermined time after the interrupter is opened.

8. In an electrical circuit, the combination with a circuit interrupter, of electrolytic valves connected in series across the terminals of the said interrupter, and arc-quenching means connected between the said valves and the ground.

9. In an electric circuit, the combination with a circuit interrupter, of an electrolytic valve connected across the terminals thereof for preventing the strikin back of an interrupted arc, and means For discharging the energy tending to create an arc to the ground.

10. In an electric circuit, the combination with a circuit interrupter, of an electrolytic valve connected across its terminals for preventing the striking back of an interrupted arc, and means connected between the valve and the ground to protect the circuit from discharges.

In testimony whereof, I have hereunto subscribed my name this 19th day of Dec. 1913.

LEWIS W. CHUBB.

Witnesses:

O. W. A. On'r'rmo, B. B. I-Invns.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C.

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