Gas blast circuit breaker of the axial blast type with magnetic means for rotating an arc terminal

Claim 1

AN ELECTRIC CIRCUIT BREAKER OF THE AXIAL-BLAST, GASBLAST TYPE COMPRISING: (A) A PAIR OF ELECTRODES BETWEEN WHICH AN ARC IS ESTABLISHED DURING CIRCUIT INTERRUPTION, (B) AN ORIFICE HAVING AN OPENING THROUGH WHICH SAID ARC IS ADAPTED TO EXTEND WHEN PRESENT BETWEEN SAID ELECTRODES, (C) MEANS FOR CAUSING A STREAM OF GAS TO PASS THROUGH SAID ORIFICE OPENING AXIALLY OF THE ARC ABOUT THE PERIPHERY OF SAID ARC, (D) PORTIONS OF SAID GAS STREAM FLOWING CLOSELY ADJACENT TO THE OUTER PERIPHERY OF THE ELECTRODE LOCATED UPSTREAM FROM SAID ORIFICE BUT SEPARATING FROM THE SURFACE OF SAID ELECTRODE IN A REGION FACING THE ORIFICE OPENING, WHEREBY TO DEFINE A STAGNATION ZONE IN SAID LATTER REGION, (E) SAID ARC HAVING AN UPSTREAM TERMINAL THAT IS HELD CAPTIVE IN SAID STAGNATION ZONE DURING A CIRCUIT INTERRUPTING OPERATION, (F) MAGNETIC MEANS FOR ROTATING SAID UPSTREAM TERMINAL ABOUT A POINT ON SAID UPSTREAM TERMINAL THAT IS HELD SAID UPSTREAM ARC TERMINAL IS HELD CAPTIVE IN SAID STAGNATION ZONE, (F'') SAID UPSTREAM ELECTRODE COMPRISING A GENERALLY CUP-SHAPED MEMBER SURROUNDING SAID MAGNETIC MEANS WITH THE BASE OF SAID CUP-SHAPED MEMBER FACING DOWNSTREAM WITH SAID STAGNATION ZONE POSITIONED ON SAID BASE, MEANS FOR FORCING CURRENT FLOWING THROUGH SAID CUP-SHAPED MEMBER TO AN ARC TERMINAL IN SAID STAGNATION ZONE TO FLOW FROM THE OUTER PERIPHERY OF SAID CUP-SHAPED MEMBER RADIALLY INWARDLY, THEREBY DEVELOPING A RADIALLY-INWARDLY ACTING MAGNETIC FORCE IN SAID ARC TO HELP HOLD THE ARC IN SAID STAGNATION ZONE. (G) SAID CUP-SHAPED MEMBER HAVING A CENTRAL REGION OF SAID BASE DISPOSED WITHIN SAID STAGNATION ZONE IN WHICH SAID MAGNETIC MEANS HAS RELATIVELY WEAK ARC ROTATING ABILITIES, (H) AND MEANS FOR PREVENTING ENTRY OF SAID UPSTREAM ARC TERMINAL INTO SAID CENTRAL REGION.