A gas circuit breaker having a pair of contacts and a pair of exhaust conductors. An exhaust hole in the pair of exhaust conductors is provided with an insulation cover having an opening. The cover has a guide on an opening end on the side near the pair of contacts and an opening end on the side far from the pair of contacts respectively. The guide has an exhaust hole protective guide and a high-temperature gas passage dividing guide. A first gas flow passage is between an exhaust hole protective guide and a high-temperature gas passage dividing guide, and a second gas flow passage is between the high-temperature gas passage dividing guides. The first gas flow passage is narrower than the second gas flow passage. An end of the exhaust hole protective guide on the first gas flow passage side is projected toward the high-temperature gas passage dividing guide.

In a gas circuit breaker according to an embodiment, a container is filled with an arc extinguishing gas. A movable part housed in the container and includes a movable arc contact. The movable part is provided with an accumulation part for increasing pressure of the arc extinguishing gas. A counter part is housed in the container and includes a counter arc contact, an exhaust pipe, and a shield. The shield is disposed in the exhaust pipe in a state that a flow of the arc extinguishing gas inside the exhaust pipe is allowed. A nozzle is housed in the container and provided with a space. An arc discharge occurs between the movable arc contact and the counter arc contact in the space. The arc extinguishing gas having an increased pressure in the accumulation part flows into the space to extinguish the arc discharge and flows into the exhaust pipe. The shield has a first shield wall crossing the axial direction of the exhaust pipe.

In a gas circuit breaker according to an embodiment, a container is filled with an arc extinguishing gas. A movable part housed in the container and includes a movable arc contact. The movable part is provided with an accumulation part for increasing pressure of the arc extinguishing gas. A counter part is housed in the container and includes a counter arc contact, an exhaust pipe, and a shield. The shield is disposed in the exhaust pipe in a state that a flow of the arc extinguishing gas inside the exhaust pipe is allowed. A nozzle is housed in the container and provided with a space. An arc discharge occurs between the movable arc contact and the counter arc contact in the space. The arc extinguishing gas having an increased pressure in the accumulation part flows into the space to extinguish the arc discharge and flows into the exhaust pipe. The shield has a first shield wall crossing the axial direction of the exhaust pipe.

An interrupter unit for a circuit breaker includes a gas-insulated housing, which is fillable with a quenching gas, and a gas-guiding structure, which is disposed in the housing and has a guide tube and at least one diverting element. The guide tube extends in tubular manner about a longitudinal axis of the interrupter unit in order to guide hot gas, which is created in an electric arc region of the interrupter unit by the heating of quenching gas by an electric arc, away from the electric arc region. The at least one diverting element is configured to set hot gas exiting from the guide tube in a circular flow running around the longitudinal axis.

An interrupter unit for a circuit breaker includes a gas-insulated housing, which is fillable with a quenching gas, and a gas-guiding structure, which is disposed in the housing and has a guide tube and at least one diverting element. The guide tube extends in tubular manner about a longitudinal axis of the interrupter unit in order to guide hot gas, which is created in an electric arc region of the interrupter unit by the heating of quenching gas by an electric arc, away from the electric arc region. The at least one diverting element is configured to set hot gas exiting from the guide tube in a circular flow running around the longitudinal axis.

An insulating molded body to be used for an arc extinguishing device of a gas circuit breaker is provided. The insulating molded body includes a fluororesin mixture which contains a fluororesin and an oxygen generator configured to generate oxygen through thermal decomposition at 450° C. or more and 1,150° C. or less with an arc generated when a conduction current is interrupted. The oxygen generator is dispersed in the fluororesin. Also provided is a gas circuit breaker including an insulating nozzle formed of the insulating molded body.

An insulating molded body to be used for an arc extinguishing device of a gas circuit breaker is provided. The insulating molded body includes a fluororesin mixture which contains a fluororesin and an oxygen generator configured to generate oxygen through thermal decomposition at 450° C. or more and 1,150° C. or less with an arc generated when a conduction current is interrupted. The oxygen generator is dispersed in the fluororesin. Also provided is a gas circuit breaker including an insulating nozzle formed of the insulating molded body.

A high voltage circuit-breaker comprising a housing defining a volume for an insulating gas, at least two making and breaking (M&B) units arranged therein, each M&B unit comprising a first and second contact element for forming an electrically conductive connection, at least the first contact element is movable along an axially extending switching axis of the high voltage circuit-breaker, and the first contact elements of the at least two M&B units are motion-coupled; a drive device connected to the first contact element of at least one M&B unit and configured for moving the first contact element along the switching axis over a moving distance for separating conductive connections; and a gas damper connected to the first contact element of the at least one M&B unit and configured for damping movement of the first contact element with a damping force increasing in relation to the moving distance.

A gas circuit breaker of an embodiment includes a sealed container, a first contact part and a second contact part, an operation mechanism, an insulating nozzle, a pressure accumulator, and an electric field shield. The insulating nozzle is displaced in conjunction with the first contact part in a separation process of the first contact part and the second contact part. The insulating nozzle surrounds arc discharge generated between the first contact part and the second contact part. The electric field shield is attached to the insulating nozzle. The electric field shield has a floating potential during a period of at least part of the separation process. The electric field shield is electrically connected to the second contact part such that the electric field shield has the same potential in a completely open electrode state in which separation between the first contact part and the second contact part is terminated.

The present application concerns a high-voltage circuit breaker filled with insulating gas having a main axis A, including arcing contacts and an insulating nozzle, wherein an insulating gas flowing from a storage chamber and heated by an electric arc between the two arcing contacts is partitioned into a first gas flow and a second gas flow conducted outside of the insulating nozzle from opposite directions toward a main gas chamber, wherein the first gas flow flows through a first intermediary gas chamber and the second gas flow flows through a second intermediary gas chamber and is partitioned in a first portion directed to the main gas chamber and a second portion directed to an exhaust gas chamber, characterized in that the first portion of the second gas flow is smaller than the second portion of the second gas flow.