Abstract: 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.

Abstract: A current cut-off device includes a plate-shaped terminal piece having a contact, a movable piece including an elastic portion formed in a plate shape so as to be elastically deformed and a movable contact arranged at one end portion of the elastic portion and having the movable contact so as to be pressed against and in contact with the contact, and a thermally actuated element which biases the movable piece by deforming in accordance with a temperature change and causes a state of the movable piece to be shifted from a conductive state in which the movable contact is in contact with the contact to a cut-off state in which the movable contact is separated from the contact. When the state of the movable piece is shifted from the conductive state to the cut-off state, as the movable contact moves, it gets over the contact.

Abstract: The breaker is provided with a fixed contact, a movable piece having an elastic portion and a movable contact, a thermally-actuated element deforming with a change in the temperature so as to shift the movable piece from a conduction state to a cut-off state, a case main body housing the movable piece and the thermally-actuated element, a lid member attached to the case main body, and a plate-shaped cover piece embedded in the lid member. The case main body is provided with a first fixing surface fixed to the lid member, and the lid member is provided with a second fixing surface fixed to the case main body. The second fixing surface is provided with a protruding portion protruding toward the first fixing surface, and the protruding portion and the cover piece are overlapped with each other in the plan view as viewed in the thickness direction of the cover piece.

Abstract: A breaker comprises: a fixed piece having a fixed contact; a movable piece having a movable contact and pressing the movable contact against the fixed contact to contact therewith; a thermally-actuated element for shifting the movable piece from a conduction state in which the movable contact contacts with the fixed contact to a turn-off state; a PCT thermistor; and a resin case. The fixed piece has a contacting portion contacting with the PCT thermistor. The resin case has a bottom surface provided with a concave portion. In a planar view when the fixed piece is viewed from the PCT thermistor, the contacting portion is disposed within the concave portion. The concave portion has a bottom recessed from the bottom surface of the resin case to prevent the bottom from protruding outwardly from the bottom surface when the thermally-actuated element is deformed.

Abstract: 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).

Abstract: 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.

Abstract: 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.

Abstract: A circuit protection element includes a first leg part formed by being bent once from a first end part of a ceiling part that is the bending reference plane; a second leg part formed by being bent once with respect to the bending reference plane; a first mounting part and a second mounting part each formed by being bent twice with respect to the bending reference plane so as to be flush mutually and parallel to a mounting surface of the circuit board; and a plastic deformation part (a curved part) set in a predetermined region of the second leg part and plastically deformed by applying a load in the vicinity of a second end part of the ceiling part toward the mounting surface of the circuit board.

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

Abstract: A breaker 1 includes a fixed piece 2 having a fixed contact 21, a movable piece 4 including a movable contact 41 and having the movable contact 41 so as to be pressed against and in contact with the fixed contact 21, a thermally actuated element 5 shifting the movable piece 4 from a conductive state to a cut-off state in accordance with a temperature change, and a case 7 accommodating the fixed piece 2, the movable piece 4, and the thermally actuated element 5. The case 7 includes a case main body 71 accommodating the movable piece 4 and the thermally actuated element 5, a lid member 81 covering a housing concave portion 73 of the case main body 71, and a metal plate 9 embedded in the lid member 81. Heat capacity of the metal plate 9 is larger than heat capacity of the fixed piece 2.