The present disclosure relates to an arc extinguishing unit of a molded case circuit breaker with a barrier provided between a fixed contact and a movable contact when a circuit is cut off. The arc extinguishing unit includes fixed contacts fixed to part of a base assembly case; movable contacts that contact or are separated from the fixed contacts; and an arc extinguishing part that extinguishes an arc generated when the movable contacts are separated from the fixed contacts. The arc extinguishing part includes a pair of side plates; multiple grids installed at a fixed interval between the side plates; and arc barriers each rotatably installed on the side plates, and configured to open between the movable contacts and the fixed contacts by being rotated when a current flows on the circuit, and to close between the movable contacts and the fixed contacts when the current is cut off.

This limiter pole (B) for a multipole DC electrical switch (2) comprises a compartment in which an input terminal and an output terminal for a direct electric current are provided, along with a first electrical contact connected to the input terminal and a second electrical contact connected to the output terminal, third and fourth electrical contacts connected to one another in series, the third and fourth contacts being capable of being moved simultaneously relative to the first and second electrical contacts, respectively, between a closed position, in which the first and third contacts and the second and fourth contacts make contact with one another so as to allow the direct electric current to flow between the input terminal and the output terminal, and an open position, in which said contacts are located away from one another, interrupting the flow of the current between the input terminal and the output terminal. The limiter pole (B) comprises a first electric arc formation chamber in which the first and third electrical contacts are placed, a second electric arc formation chamber in which the second and fourth electrical contacts are placed, and first and second electric arc extinguishing chambers which are associated with the first and second electric arc formation chambers, respectively.

An unit has a plurality of arc quenching plates and an electrically isolative housing, the plurality of arc quenching plates adjacent to each other are spaced to form an arc channel. Each one of the plurality of arc quenching plates has a mounting portion and a receiving portion, the receiving portion has a distributing part, the distributing part has a through hole penetrating through the receiving portion and an inclined plane protruding from the receiving portion, the inclined plane is arranged to a side of the through hole away from an arc entrance and extending to the arc entrance, an angle between the inclined plane and the receiving portion is an acute angle, a root of the inclined plane is continuous with the receiving portion. An inclined plane of a first arc quenching plate is interlacing and opposite with an inclined plane of a second arc quenching plate.

The present disclosure relates to an arc extinguishing unit of a molded case circuit breaker with a barrier provided between a fixed contact and a movable contact when a circuit is cut off. The arc extinguishing unit includes fixed contacts fixed to part of a base assembly case; movable contacts that contact or are separated from the fixed contacts; and an arc extinguishing part that extinguishes an arc generated when the movable contacts are separated from the fixed contacts. The arc extinguishing part includes a pair of side plates; multiple grids installed at a fixed interval between the side plates; and arc barriers each rotatably installed on the side plates, and configured to open between the movable contacts and the fixed contacts by being rotated when a current flows on the circuit, and to close between the movable contacts and the fixed contacts when the current is cut off.

The invention relates to an arc quenching plate for quenching arcs. The arc quenching plate comprises a mounting portion suitable for mounting and a receiving portion suitable for receiving arcs, the receiving portion comprises a distributing part suitable for separating arcs, the distributing part comprises a through hole penetrating through the receiving portion and an inclined plane protruding from the receiving portion, the inclined plane is arranged to a side of the through hole away from an arc entrance and extending to the arc entrance, an angle between the inclined plane and the receiving portion is an acute angle, a root of the inclined plane is continuous with the receiving portion. The arc quenching plate and the arc quenching unit of the present invention have following benefit, in the same space, an arc can be separated into much more pieces of short arc.

The electrical switch includes a first and a second fixed contact, and a rotatable knife contact including at least one pair of blades being flexibly connected to each other and rotating around a rotational axis. A third fixed contact is positioned on an opposite side of the rotational axis in relation to the adjacent first and second fixed contact and a middle portion of the rotatable knife contact is electrically connected to the third fixed contact. The rotatable knife contact connects in a first switching position the first fixed contact and in a second switching position the second fixed contact to the third fixed contact.

The electrical switch includes a first and a second fixed contact, and a rotatable knife contact including at least one pair of blades being flexibly connected to each other and rotating around a rotational axis. A third fixed contact is positioned on an opposite side of the rotational axis in relation to the adjacent first and second fixed contact and a middle portion of the rotatable knife contact is electrically connected to the third fixed contact. The rotatable knife contact connects in a first switching position the first fixed contact and in a second switching position the second fixed contact to the third fixed contact.

A switch includes a first fixed contact, a second fixed contact, a movable contact, a drive shaft, a first outside yoke, a second outside yoke, a first inside yoke, a second inside yoke, and a permanent magnet. The permanent magnet magnetically couples the first outside yoke, the second outside yoke, the first inside yoke, and the second inside yoke, and produces a magnetic field component in a direction in which the first fixed contact point and the second fixed contact point are aligned, between the first fixed contact point and the first movable contact point and between the second fixed contact point and the second movable contact point.

Switching devices having a contact point, and an arc extinguishing chamber are used to blow switch arcs. The arc extinguishing chamber may have an exit opening through which plasma, generated inside the switching device by a switch arc developing when the contact point opens, exits out of the switching device. Inside the extinguish chamber a first arc guide plate may be provided that extends from the contact point toward the exit opening and which guides and stretches the switch arc. The switch arc may be initially stretched beyond the dimensions of the exit opening by the first arc guide plate and then the stretching may be reduced to be within the dimensions of the exit opening by an arc guide pin projecting from the first arc guide plate.

Switching devices having a contact point, and an arc extinguishing chamber are used to blow switch arcs. The arc extinguishing chamber may have an exit opening through which plasma, generated inside the switching device by a switch arc developing when the contact point opens, exits out of the switching device. Inside the extinguish chamber a first arc guide plate may be provided that extends from the contact point toward the exit opening and which guides and stretches the switch arc. The switch arc may be initially stretched beyond the dimensions of the exit opening by the first arc guide plate and then the stretching may be reduced to be within the dimensions of the exit opening by an arc guide pin projecting from the first arc guide plate.