A circuit interrupter includes: a first fixed terminal including a first fixed contact; a movable contactor which is formed as a separate part from the first fixed terminal and includes a first movable contact; a holding unit configured to hold the movable contactor so that the first movable contact is connected to the first fixed contact; and a squib configured to generate gas by combustion. In the circuit interrupter, pressure of the gas generated by the squib causes movement of the movable contactor in a direction away from the first fixed terminal so that the first movable contact is separated from the first fixed contact.

A breaker includes a fixed piece having a fixed contact, a movable piece having an elastically deformable elastic portion and a movable contact formed at a tip portion of the elastic portion and pushed to contact with the fixed contact, a thermally actuated element deformable according to a temperature change to shift the state of the movable piece from a conductive state to a cut-off state, and a case accommodating the fixed piece, the movable piece, and the thermally actuated element. The movable piece is cantilevered by the case on a base end portion side of the elastic portion, the elastic portion includes a first narrow portion having a smaller width dimension in a short direction perpendicular to a longitudinal direction of the elastic portion than the base end portion, and the first narrow portion has an arc-shaped contour in plan view from a thickness direction of the elastic portion.

A switch includes: an ignition chamber; a pyrotechnic actuator for releasing gas into the ignition chamber upon ignition; a first conductor and a second conductor, the first and second conductors including connection contacts; a third conductor moveable in a direction from a first position towards a second position upon actuation by the pyrotechnic actuator; and a breakable retaining member for retaining the third conductor in the first position prior to actuation by the pyrotechnic actuator, the retaining member breaking upon actuation of the pyrotechnic actuator to allow movement of the third conductor. In the first position, the third conductor is arranged between, and in electrical and physical contact with, the first and second conductors to define a current conduction path. In the second position, the third conductor is electrically and physically separate from the first and second conductors.

The breaker 1 is provided with a fixed contact 20, a movable piece 4 extending in a first direction (D1), a thermally actuated element 5, a case 7 accommodating the movable piece 4 and the thermally actuated element 5, and a terminal piece 2 which partially protrudes outside the case 7 and is to be electrically connected with an external circuit. The terminal piece 2 has a first portion 21 and a second portions 22 having different heights from a bottom surface of the case 7, a first bent portion (23a) bent in a first bending direction, and a second bent portion (23b) bent in a second bending direction opposite to the first bending direction. The first bent portion (23a) and the second bent portion (23b) extend in parallel with the first direction (D1).

A breaker 1 includes a fixed piece 2 having a fixed contact 21, a movable piece 4 having an elastically deformable elastic portion 44 and a movable contact 41 formed at a tip portion of the elastic portion 44 and pushed to be in contact with the fixed contact 21, a thermally actuated element 5 deformable in accordance with a temperature change to shift the state of the movable piece 4 from a conductive state to a cut-off state, and a case 10 accommodating the fixed piece 2, the movable piece 4, and the thermally actuated element 5. The movable piece 4 is cantilevered and supported by the case 10 on a base end portion (44s) side of the elastic portion 44, the elastic portion 44 includes a first narrow portion 45 having a smaller width dimension (W) in a short direction (D2) perpendicular to a longitudinal direction (D1) of the elastic portion 44 than that of the base end portion (44s), and the first narrow portion 45 has an arc-shaped contour 46 in a plan view seen from a thickness direction of the elastic portion 44.

A switch includes: an ignition chamber; a pyrotechnic actuator for releasing gas into the ignition chamber upon ignition; a first conductor and a second conductor, the first and second conductors including connection contacts; a third conductor moveable in a direction from a first position towards a second position upon actuation by the pyrotechnic actuator; and a breakable retaining member for retaining the third conductor in the first position prior to actuation by the pyrotechnic actuator, the retaining member breaking upon actuation of the pyrotechnic actuator to allow movement of the third conductor. In the first position, the third conductor is arranged between, and in electrical and physical contact with, the first and second conductors to define a current conduction path. In the second position, the third conductor is electrically and physically separate from the first and second conductors.

A breaker has a fixed contact, a movable piece which has an elastic portion formed in a plate shape and being elastically deformable, and a movable contact in one end portion of the elastic portion so as to press the movable contact against the fixed contact, a thermally-actuated element which is deformed in accordance with a temperature change and shifts from a conduction state in which the movable contact contacts with the fixed contact to a shut-off state in which the movable contact separates from the fixed contact, and a case which accommodates the fixed contact, the movable piece, and the thermally-actuated element. The case has a side wall extending in a long direction of the movable piece, and the side wall is provided, in an adjacent portion to the thermally-actuated element, with a convex portion protruding toward the outside of the case.

Provided is a breaker capable of further downsizing without impairing rigidity and strength of a case. The breaker 1 comprises a fixed contact 21, a movable piece 4 having and pressing a movable contact 41 to the fixed contact 21, a thermally responsive element 5 for moving the movable piece 4 to separate the movable contact 41 from the fixed contact 21 by deformation thereof responding to temperature change, a case for containing the fixed piece 21, the movable piece 4 and the thermally responsive element 5, and a cover piece 8 attached on the case 7. The case 7 has an end face 72 on which the cover piece 8 is disposed, a containing recess 73 caved from the end face 72 and forming a space to which the movable piece 4 and the thermally responsive element 5 are contained, and a first protrusion protruding from the end face 72 and to which the cover piece 8 is fitted.

A temperature actuated switch (1) includes: first and second temperature sensing sections (10, 20) that each include a contact (12, 22) and a thermally deformable member (first bimetal 11, second bimetal 21) that is bent in accordance with a temperature rise from a normal temperature in a manner such that the contacts (12, 22) shift from an open state to a connected state, the contacts (12, 22) being provided on a free-end side and located on the individual surfaces of the first and second temperature sensing sections that face each other; first, second, and third terminals (31, 32, 33) connected to an external circuit; and an insulation section (40) that maintains the first, second, and third terminals (31, 32, 33) in an insulated state, wherein the first temperature sensing section (10) includes first and second regions (A1, A2) with a slit (13) that extends from a fixed-end side to the free-end side provided therebetween, the first terminal (31) is connected to the first region (A1), the second terminal (32) is connected to the second region (A2), and the third terminal (33) is connected to the second temperature sensing section (20).

The breaker 1 is provided with a fixed contact 20, a movable piece 4 extending in a first direction (D1), a thermally actuated element 5, a case 7 accommodating the movable piece 4 and the thermally actuated element 5, and a terminal piece 2 which partially protrudes outside the case 7 and is to be electrically connected with an external circuit. The terminal piece 2 has a first portion 21 and a second portions 22 having different heights from a bottom surface of the case 7, a first bent portion (23a) bent in a first bending direction, and a second bent portion (23b) bent in a second bending direction opposite to the first bending direction. The first bent portion (23a) and the second bent portion (23b) extend in parallel with the first direction (D1).