Puffer-type gas circuit-interrupter

Claim 1

A puffer-type gas-blast circuit-interrupter including an elongated hollow insulating casing means (32), a first metallic end-plate member (163) closing one open end of said hollow insulating casing means (32), a tubular elongated relatively-stationary venting contact, relatively stationary contact-supporting metallic means mounted upon the inner side of said metallic end-plate member (163) and supporting said relatively-stationary tubular venting contact by a lost-motion connection, said metallic supporting means for said tubular elongated relatively-stationary venting contact (150) being disposed rearwardly from the forward contacting tip of said venting contact (150), contact-biasing means (179) associated with said contact-supporting means and biasing said relatively-stationary tubular venting contact in a direction toward the interior of said elongated hollow insulating casing means (32), a movable operating cylinder-assembly comprising an axially-extending hollow insulating nozzle (157) and a tubular elongated venting movable contact making contacting valve-like abutment engagement with said relatively-stationary tubular venting contact in the closed-circuit position of the circuit-interrupter, a second metallic end-plate member (164) closing the other open end of said hollow insulating casing means (32), means defining a fixed piston member located intermediate the ends of said hollow insulating casing means over which said movable operating cylinder-assembly operatively slides during the opening operation to thereby compress gas therewithin, supporting means affixed to the inner side of said second metallic end-plate member (164) and extending interiorly of said hollow insulating casing means to fixedly support therein said fixed piston member, said axially-extending hollow insulating nozzle (157) surrounding said relatively-stationary tubular venting contact in the closed-circuit position of the circuit-interrupter, means defining an annular apertured metallic cooler-member (56) disposed entirely interiorly of said hollow insulating nozzle (157) so as not to project externally up to the surface of said movable operating cyclinder-assembly, cylinder-assembly, said stationary and movable venting contacts being separable to establish an arc during a circuit-interrupter opening operation, said annular apertured metallic cooler member being closely located to the contact tip of the movable tubular venting elongated contact so as thereby to cool the compressed gas ejected from the interior of said movable operating cylinder through said hollow nozzle and axially along said drawn arc, the abutting contacting engagement between the stationary and movable venting contacts during the opening operation of the circuit-interrupter and also during the time of take-up of the lost-motion travel for the stationary venting contact providing a desirable valve-closed action to thereby retain and build up gas pressure during the compression phase within said movable operating cylinder until a predetermined time, coincident with the take-up of said lost-motion, whereupon contact separation between the stationary and movable venting contacts occurs and only then compressed gas ejection takes place through the hollow movable insulating nozzle for arc-extinction purposes therein, supporting means affixed to the inner side of the second metallic-end-plate member (164) including longitudinally-extending guide rail means, and a lazy-tong multiplying operating mechanism disposed internally of said casing means and guided by said guide rail means to provide a very fast opening and closing motion of the movable operating cylinder and the movable venting contact movable therewith.