The invention concerns a double-motion circuit breaker comprising primary and secondary movable contacts slidingly mounted within primary and secondary holders, wherein the primary movable contact comprises a tulip and a contact cylinder attached thereto, and the secondary movable contact comprises a pin for engaging the tulip but no counter-contact for engaging the contact cylinder. The circuit breaker also has a non-linear linkage mechanism with a pin and slot mechanism, and a fixed dielectric shield provided on the secondary holder. During disconnection, the linkage mechanism is preferably arranged to move the pin more than the tulip, proportionally to their maximum stroke, so as to quickly bring the pin tip within the fixed dielectric shield, whereafter the tulip moves more than the pin. This circuit breaker is cheaper, lighter and can be disconnected more quickly.

A bidirectional driving mechanism 10 has a drive-side linkage rod 11, a driven-side linkage rod 13, two levers 12 that link the drive-side linkage rod with the driven-side linkage rod, and a guide 14 that regulates the operation of the drive-side linkage rod 11 and the driven-side linkage rod 13. A moveable pin 18 is passed through a first groove cam 16 of the drive-side linkage rod 11, a second groove cam 17 of the guide 14, and third groove cams 19 of the levers 12, and by operation of the drive-side rod 13, the moveable pin 18 moves within the respective groove cams 16, 17, 19, causing the levers 12 to rotate, the driven-side linkage rod 13 to be driven in a direction opposite to the drive-side linkage rod 11, and a driven-side arc electrode 5 to be driven in a direction opposite to a drive-side arc electrode 4.

To provide a gas circuit breaker having a space-saving reliable double motion mechanism having a high degree of freedom in design. A double motion mechanism section of the gas circuit breaker is formed of a drive-side connecting rod, a driven-side connecting rod, levers connecting them and a guide regulating operations of the drive-side connecting rod and the driven-side connecting rod. A movable pin is connected to a first grooved cam formed in the drive-side connecting rod, a second grooved cam formed in the guide and third grooved cams formed in the levers respectively, and posture holding members are provided in the movable pin. The movable pin moves in the respective grooved cams by an operation of the drive-side connecting rod, thereby rotating the levers, driving the driven-side connecting rod in an opposite direction of the drive-side connecting rod, and driving the driven-side arcing contact in an opposite direction of the driven-side arcing contact.

The present disclosure may allow the movable base and the second movable contact driven in a dual-motion manner to be connected by a plurality of levers, and a force transferred to the movable base while the plurality of levers are in close contact with one another or released from the close contact may be transferred to the second movable contact, and thus a size of the levers may not be required to increase even when a stroke ratio between the movable base and the second movable contact increases, thereby having an effect capable of minimizing a size of the gas circuit breaker as well as appropriately controlling a stroke ratio between the movable base and the second movable contact.

The present disclosure may allow the movable base and the second movable contact driven in a dual-motion manner to be connected by a plurality of levers, and a force transferred to the movable base while the plurality of levers are in close contact with one another or released from the close contact may be transferred to the second movable contact, and thus a size of the levers may not be required to increase even when a stroke ratio between the movable base and the second movable contact increases, thereby having an effect capable of minimizing a size of the gas circuit breaker as well as appropriately controlling a stroke ratio between the movable base and the second movable contact.

Realized is a shape of a grooved cam that maximizes break performance by appropriately setting an electrode operation, with a minimum weight increase. A gas circuit breaker includes a drive side electrode and a driven side electrode which are disposed to face each other in a sealed tank, the drive side electrode having a drive side main electrode and a drive side arcing contact, the driven side electrode having a driven side main electrode and a driven side arcing contact, the drive side arcing contact being connected to an operating device, and the driven side arcing contact being connected to a double motion mechanism portion, in which the double motion mechanism portion includes a drive side connection rod that receives driving force from the drive side electrode, a driven side connection rod that is connected to the driven side arcing contact, a lever that is bent to the operating device side around a rotation axis by causing the driven side connection rod to operate in an opposite direction with respect to an operation of the drive side connection rod, and a guide that defines operations of the drive side connection rod and the driven side connection rod.

A bidirectional driving mechanism 10 has a drive-side linkage rod 11, a driven-side linkage rod 13, two levers 12 that link the drive-side linkage rod with the driven-side linkage rod, and a guide 14 that regulates the operation of the drive-side linkage rod 11 and the driven-side linkage rod 13. A moveable pin 18 is passed through a first groove cam 16 of the drive-side linkage rod 11, a second groove cam 17 of the guide 14, and third groove cams 19 of the levers 12, and by operation of the drive-side rod 13, the moveable pin 18 moves within the respective groove cams 16, 17, 19, causing the levers 12 to rotate, the driven-side linkage rod 13 to be driven in a direction opposite to the drive-side linkage rod 11, and a driven-side arc electrode 5 to be driven in a direction opposite to a drive-side arc electrode 4.

To provide a gas circuit breaker having a space-saving and highly reliable double motion mechanism with high design freedom. In a double motion mechanism of the gas circuit breaker, a driven side movable pin is communicated with a lever driven side hole cut in the opposite side with respect to a rotation axis of a lever. A round hole through which a driving side movable pin is inserted and an elongate hole through which the driven side movable pin is inserted are cut in the outside of the lever. A position retaining member to suppress rotation of the driving side movable pin about two axes vertical to a pin axis is provided. The driving side movable pin is moved in respective grooved cams with an operation of the driving side rod, to rotate the lever, drive the driven side connecting rod in an opposite direction to the driving side connecting rod, and drive the driven side arcing contact in an opposite direction to the driving side arcing contact.

A gas circuit breaker includes a driving side electrode having a driving side main contact and a driving side arc contact, and a driven side electrode having a driven side main contact and a driven side arc contact in a sealed tank. The driving side electrode is connected to an operation device. The driven side electrode is coupled to a bidirectional driving mechanism unit. A sliding guide, on which the driven side main contact slides, is provided on an inner periphery side of the driven side main contact. The driven side main contact is energized by a coil spring in a direction of the sliding guide and has two contact surfaces. Only during normal conduction, one of the contact surfaces contacts a projected portion of the sliding guide and the other of the contact surfaces contacts the driving side main contact.

An electric switching device contains a first contact piece and a second contact piece. The first contact piece can be driven by a first kinematic chain. The second contact piece can be driven by a second kinematic chain. The electric switching device contains a first switching point and a second switching point, which are electrically connected in series, the first contact piece being associated with the first switching point and the second contact piece with the second switching point.