The invention relates to a medium-, high-, or very high-voltage circuit breaker, comprising at least one arc-control chamber and an outer casing in which the arc-control chamber is arranged. The circuit breaker includes a discharge cap (40) forming a portion of the outer wall external of the arc-control chamber (12), the discharge cap being situated inside the outer casing and internally defining a gas-flow chamber (31). In the invention, the discharge cap (40) includes at least one portion (40′) that is movable under the effect of the gas pressure in the gas-flow chamber (31), in such a manner that its volume is extensible.

A circuit breaker including a stationary frame, at least a pair of arc contacts, an actuation rod, a compression chamber in which a portion of the dielectric gas is compressed; a cylinder and a piston connected with the rod, which are movable within the stationary frame along main axis, for compressing the portion of the dielectric gas in the compression chamber; a link mechanism connecting the piston to the rod, wherein the stationary frame includes a cylindrical portion with which each of the piston and of the cylinder are radially in gastight contact and which bounds the compression chamber together with the piston and the cylinder.

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.

The invention relates to a medium-, high-, or very high-voltage circuit breaker, comprising at least one arc-control chamber and an outer casing in which the arc-control chamber is arranged. The circuit breaker includes a discharge cap (40) forming a portion of the outer wall external of the arc-control chamber (12), the discharge cap being situated inside the outer casing and internally defining a gas-flow chamber (31). In the invention, the discharge cap (40) includes at least one portion (40) that is movable under the effect of the gas pressure in the gas-flow chamber (31), in such a manner that its volume is extensible.

A circuit breaker including a stationary frame, at least a pair of arc contacts, an actuation rod, a compression chamber in which a portion of the dielectric gas is compressed; a cylinder and a piston connected with the rod, which are movable within the stationary frame along main axis, for compressing the portion of the dielectric gas in the compression chamber; a link mechanism connecting the piston to the rod, wherein the stationary frame includes a cylindrical portion with which each of the piston and of the cylinder are radially in gastight contact and which bounds the compression chamber together with the piston and the cylinder.

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 contact arrangement has a longitudinal axis and includes a first contact group with a first contact and a second contact and a second contact group with a third contact and a fourth contact. The first contact interacts electrically and mechanically with the third contact, and/or the second contact interacts electrically and mechanically with the fourth contact, for closing and opening the contact arrangement. At least one mechanical coupling is provided for transmitting an actuation force to the second contact group and thereby moving the second contact group. The at least one mechanical coupling is adapted to move the third and the fourth contact in such a way that their speeds differ along at least a portion of a travel path of the third contact or along at least a portion of a travel path of the fourth contact.

The invention provides electric power line switchgear (10) comprising a main movable contact (14) and a secondary movable contact (16), capable of moving along a main axis A of the switchgear (10), in which the main movable contact (14) is connected to the secondary movable contact (16) by means of a crank mechanism (20) that transforms the movement of the main movable contact (14) in one direction into a movement of the secondary movable contact (16) in an opposite direction; the switchgear being characterized in that the crank mechanism (20) comprises two levers (22, 24) mounted to pivot relative to the stationary housing (12) about respective parallel pivot axes (B, C), each lever (22, 24) being connected firstly to a respective one of the main movable contact (14) and the secondary movable contact (16), and secondly to the other lever (24, 22).