A temperature-dependent switch comprising first and second stationary contacts and a temperature-dependent switching mechanism having a movable contact member. The switching mechanism, in its first switching position, presses the contact member against the first contact and thereby produces an electrically conductive connection and, in its second switching position, keeps the contact member spaced apart from the first contact and thereby disconnects the electrically conductive connection. The switch further comprises a closing lock that, once activated, prevents the switch once having opened from closing again by keeping the switching mechanism in its second switching position. The closing lock comprises a locking element having a shape-memory alloy and is configured to change its shape upon exceeding a locking element switching temperature from a first shape, in which the locking element does not activate the closing lock, into a second shape, in which the locking element activates the closing lock.

An electrical connector provided with a varistor, and to a protection device for incorporation into an electrical connector and having a varistor comprising at least two pins including a first pin which is a live (502) or neutral (504) pin and a second pin which is an earth pin (506), the first and second pins (502, 504, 506) extending through respective apertures (512) in a varistor plate (514) which has first and second faces, wherein a first conductive layer on the first face of the varistor plate (514) connects electrically to the first pin (502, 504) and a second conductive region on the second face of the varistor plate connects electrically to the second pin (506), so that in response to an excessive voltage across the first (502, 504) and second (506) pins the varistor plate will conduct electricity between the first (502, 504) and second (506) pins. The arrangement can easily be adopted in connectors conforming to existing standards, such as existing mains electrical plugs (500).

An electrical connector provided with a varistor, and to a protection device for incorporation into an electrical connector and having a varistor comprising at least two pins including a first pin which is a live (502) or neutral (504) pin and a second pin which is an earth pin (506), the first and second pins (502, 504, 506) extending through respective apertures (512) in a varistor plate (514) which has first and second faces, wherein a first conductive layer on the first face of the varistor plate (514) connects electrically to the first pin (502, 504) and a second conductive region on the second face of the varistor plate connects electrically to the second pin (506), so that in response to an excessive voltage across the first (502, 504) and second (506) pins the varistor plate will conduct electricity between the first (502, 504) and second (506) pins. The arrangement can easily be adopted in connectors conforming to existing standards, such as existing mains electrical plugs (500).

A temperature-dependent switch with a housing, which comprises a cover part having an upper side and a lower part having a raised peripheral wall, the upper section of which is bent onto the upper side of the cover part and thereby holds the cover part on the lower part, wherein two contact surfaces are provided outside at the housing and a switching mechanism is arranged in the housing, wherein the switching mechanism is configured to switch, depending on its temperature, between a closed state, in which the switching mechanism establishes an electrically conductive connection between the two contact surfaces, and an open state, in which the switching mechanism interrupts the electrically conductive connection between the two contact surfaces. A sealing ring is arranged on the upper side of the cover part, which sealing ring is in sealing contact with the bent upper section of the wall.

A temperature-dependent switch with a housing, which comprises a cover part having an upper side and a lower part having a raised peripheral wall, the upper section of which is bent onto the upper side of the cover part and thereby holds the cover part on the lower part, wherein two contact surfaces are provided outside at the housing and a switching mechanism is arranged in the housing, wherein the switching mechanism is configured to switch, depending on its temperature, between a closed state, in which the switching mechanism establishes an electrically conductive connection between the two contact surfaces, and an open state, in which the switching mechanism interrupts the electrically conductive connection between the two contact surfaces. A sealing ring is arranged on the upper side of the cover part, which sealing ring is in sealing contact with the bent upper section of the wall.

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.

The breaker 1 is provided with a fixed contact 21, a movable piece 4 having an elastic portion 43 and a movable contact 41, a thermally-actuated element 5 deforming with a change in the temperature so as to shift the movable piece 4 from a conduction state to a cut-off state, a case main body 7 housing the movable piece 4 and the thermally-actuated element 5, a lid member 8 attached to the case main body 7, and a plate-shaped cover piece 9 embedded in the lid member 8. The case main body 7 is provided with a first fixing surface 75 fixed to the lid member 8, and the lid member 8 is provided with a second fixing surface 85 fixed to the case main body 7. The second fixing surface 85 is provided with a protruding portion 86 protruding toward the first fixing surface 75, and the protruding portion 86 and the cover piece 9 are overlapped with each other in the plan view as viewed in the thickness direction of the cover piece 9.

The breaker 1 is provided with a fixed contact 21, a movable piece 4 having an elastic portion 43 and a movable contact 41, a thermally-actuated element 5 deforming with a change in the temperature so as to shift the movable piece 4 from a conduction state to a cut-off state, a case main body 7 housing the movable piece 4 and the thermally-actuated element 5, a lid member 8 attached to the case main body 7, and a plate-shaped cover piece 9 embedded in the lid member 8. The case main body 7 is provided with a first fixing surface 75 fixed to the lid member 8, and the lid member 8 is provided with a second fixing surface 85 fixed to the case main body 7. The second fixing surface 85 is provided with a protruding portion 86 protruding toward the first fixing surface 75, and the protruding portion 86 and the cover piece 9 are overlapped with each other in the plan view as viewed in the thickness direction of the cover piece 9.

A temperature switch includes a temperature detection unit configured to detect a temperature so as to move a movable contact to a position that is in contact with a fixed contact and to a position that is separated from the fixed contact, a first lead wire that is connected to the fixed contact and that includes a covering member, a second lead wire that is connected to the movable contact and that includes a covering member, and a first-insulation-case member and a second-insulation-case member each of which includes a first-lead-wire concave portion and a second-lead-wire concave portion, and which are fit into each other so as to form accommodation space S that accommodates the temperature detection unit, the movable contact, and the fixed contact, where first-lead-wire concave portion accepts insertion of the covering member of the first lead wire and the second-lead-wire concave portion accepts insertion of the covering member of the second lead wire.

A DC circuit breaker includes a case, two fixed contacts, two movable contacts, a bypass plate electrically connecting the two movable contacts, a moving block to move the bypass plate, a moving block biasing member to bias the moving block in a direction away from the fixed contacts, a thermally responsive member, a latch, a shutter, and a shutter biasing member. The thermally responsive member deforms when an installation surface equals or exceeds a prescribed temperature. The latch restricts movement of the moving block by locking the moving block when the thermally responsive member is in a pre-deformation state. The latch cancels the restriction of the movement the thermally responsive member deforms. The shutter is insertable between the fixed contacts and the movable contacts. The shutter biasing member constantly biases the shutter in a direction to be inserted between the fixed contacts and the movable contacts.