Gas-blast downstream-type of high-voltage circuit breaker having field-controlling shields and single venting movable contact

Claim 2

In a circuit interrupter, in combination, a metal tank containing an interrupting gas at a relatively high pressure, terminal bushings extending through opposite ends of the tank, a hollow stationary contact supported by the inner end of each bushing, hollow movable contacts for engaging the stationary contacts to establish a circuit through the interrupter, means for actuating the movable contacts to interrupt the circuit at two breaks, a main blast valve controlling the flow of gas from inside the tank through the movable contacts to the exterior of the tank, and a secondary blast valve at each stationary contact responsive to the current flow through the interrupter controlling the flow of gas from inside the tank through the stationary contacts to the exterior of the tank during interruption of the circuit.

Claim 3

The combination defined in claim 1, including electromagnetic means for operating the secondary blast valves.

Claim 4

The combination defined in claim 2, wherein the electromagnetic means is inductively energized by the current to be interrupted.

Claim 5

The combination defined in claim 1, including a main conductor for the current to be interrupted, a flexible conductor physically and electrically paralleling the main conductor, and linkage means connected to the flexible conductor for operating a secondary blast valve.

Claim 6

The combination defined in claim 1, including an arc probe at each stationary contact, and electromagnetic means connected to the arc probe to be energized by the arc current to operate a secondary blast valve.

Claim 7

The combination defined in claim 1, including mechanical means for operating the secondary blast valves, and time delay means for stopping the flow of gas a predetermined time after the secondary valves are opened.

Claim 8

The combination defined in claim 1, including fluid-pressure actuating means for opening the secondary blast valves, and means for reclosing the secondary valves a predetermined time after interruption of the circuit.

Claim 9

The combination defined in claim 1, including a cross arm rotatably mounted in the tank, and wherein the hollow movable contacts are on the ends of the cross arm, and the circuit through the interrupter is interrupted at two breaks when the cross arm is rotated in one direction.

Claim 10

The combination defined in claim 1, including a central housing disposed within the tank, and wherein the hollow movable contacts are reciprocably disposed in the central housing, and including linkage means for actuating said movable contacts.

Claim 11

The combination defined in claim 9, wherein the central housing connects the movable contacts in series-circuit relation.

Claim 12

A compressed-gas circuit interrupter including, in combination, stationary contact means, first shield means spaced away from said stationary contact means and having a first orifice opening provided therethrough, resistance contact means disposed within said first orifice opening, resistance means electrically connected between said stationary contact means and said resistance contact means for lowering the rate of rise of the recovery-voltage transient during the opening operation, second shield means having a second orifice opening therethrough, a movable tubular venting coNtact movable through said second orifice opening and through said first orifice opening and also into contacting engagement with the stationary contact means during the closing operation, whereby during the opening operation a resistance arc is established between the movable tubular venting contact and the resistance contact means, means for forcing a blast of compressed gas through the movable tubular venting contact to effect extinction of the resistance arc, and the two shield means directing the gas flow during the opening operation and additionally providing a substantially uniform voltage gradient across the separated contacts in the open-circuit position.

Claim 13

A compressed-gas circuit interrupter including, in combination, stationary contact means, first shield means spaced away from said stationary contact means and having a first orifice opening provided therethrough, resistance contact means disposed within said first orifice opening, resistance means electrically connected between said stationary contact means and said resistance contact means for lowering the rate of rise of the recovery-voltage transient during the opening operation, second shield means having a second orifice opening therethrough, a movable tubular venting coNtact movable through said second orifice opening and through said first orifice opening and also into contacting engagement with the stationary contact means during the closing operation, whereby during the opening operation a resistance arc is established between the movable tubular venting contact and the resistance contact means, means for forcing a blast of compressed gas through the movable tubular venting contact to effect extinction of the resistance arc, and the two shield means directing the gas flow during the opening operation and additionally providing a substantially uniform voltage gradient across the separated contacts in the open-circuit position.

Claim 14

The combination according to claim 11, wherein venting means is additionally provided through the stationary contact means.

Claim 15

The combination according to claim 12, wherein a secondary blast-valve is associated with the venting means through the stationary contact means.

Claim 16

The combination of claim 13, wherein the secondary blast-valve is electromagnetically operated.

Claim 17

The combination of claim 13, wherein a filter surrounds the secondary blast-valve.

Claim 18

The combination of claim 14, wherein induction coils are utilized.