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.

A current cut-off device 1 includes a plate-shaped terminal piece 2 having a contact 21, a movable piece 4 including an elastic portion 44 formed in a plate shape so as to be elastically deformed and a movable contact 41 arranged at one end portion of the elastic portion 44 and having the movable contact 41 so as to be pressed against and in contact with the contact 21, and a thermally actuated element 5 which biases the movable piece 4 by deforming in accordance with a temperature change and causes a state of the movable piece 4 to be shifted from a conductive state in which the movable contact 41 is in contact with the contact 21 to a cut-off state in which the movable contact 41 is separated from the contact 21. When the state of the movable piece 4 is shifted from the conductive state to the cut-off state, as the movable contact 41 moves, it gets over the contact 21.

A temperature-dependent switching mechanism is equipped with a bimetal snap-action disc and a spring snap-action disc, which carries a movable contact part, the bimetal snap-action disc and the spring snap-action disc being captively held in an annular frame.