A protection device comprises a resin base, PTC component, bimetal component, arm and upper plate which are housed in a resin housing wherein the base includes a terminal integrated with the base by insert molding. A resin cover is formed by insert molding to cover the PTC component, bimetal component, arm and upper plate which are superposed in this order over the terminal within a space in the base. The space in the resin base is substantially closed by the upper plate, the base and the cover are integrally bonded to define the resin housing, the terminal and the arm are electrically connected in series in a normal state, and in an abnormal state where the bimetal component is activated, the terminal and the arm are electrically cut off, while the terminal, PTC component, bimetal component, and arm are electrically connected in series in this order.

A thermal cut-off device includes a plastic base, two electrodes, a temperature sensing element, and a plastic cover that fits over the base. The temperature sensing element is curved downward, and may be a bimetal or a trimetal. When the device is subject to an over-temperature condition, the orientation of the curve flips such that the temperature sensing element is then curved upward. When the temperature sensing element is curved upward, it lifts an arm of one of the electrodes, which severs the electrical connection between the electrodes. In this manner the device shuts off during an over-temperature condition in order to protect the circuit in which the device is installed. To prevent corrosion of the temperature sensing element, a first moisture insulation layer is applied to the outer surface of the thermal cut-off device. The moisture insulation layer may be an epoxy adhesive or a UV/visible light-cured adhesive or light/heat cured adhesive. In some embodiments, a second moisture insulation layer is formed on the surface of the temperature sensing element.

At a contact switch, an arc generated between two contacts is controlled. An arc binding mechanism 100 includes: a first contact 111 and a second contact 121 that are capable of being contacted and separated; and a substantially ring-shaped arc binder 130 that is made of a magnetic material, is electrically insulated from a circuit including the first contact and the second contact, has an axis in parallel with a direction of a gap between the first contact and the second contact in a case in which the first contact and the second contact are in a non-contact state, and is provided so as to encircle the gap.

A temperature switch includes an elastically deformable movable plate, a movable contact on the movable plate, a fixed contact facing the movable contact, a thermally deformable member, a vibration suppression section, and a cover. The thermally deformable member is elastically deformed in accordance with a temperature change to elastically deform the movable plate such that the movable contact is in contact with the fixed contact or spaced apart from the fixed contact. The vibration suppression section suppresses vibrations of the movable plate by contacting a fixed-edge side when the movable plate is elastically deformed to shift the movable plate from being in contact with the fixed contact to being spaced apart therefrom. The cover surrounds the movable and fixed contacts, and the vibration suppression section is a projecting section provided on the cover.

A temperature switch includes an elastically deformable movable plate, a movable contact on the movable plate, a fixed contact facing the movable contact, a thermally deformable member, a vibration suppression section, and a cover. The thermally deformable member is elastically deformed in accordance with a temperature change to elastically deform the movable plate such that the movable contact is in contact with the fixed contact or spaced apart from the fixed contact. The vibration suppression section suppresses vibrations of the movable plate by contacting a fixed-edge side when the movable plate is elastically deformed to shift the movable plate from being in contact with the fixed contact to being spaced apart therefrom. The cover surrounds the movable and fixed contacts, and the vibration suppression section is a projecting section provided on the cover.

A temperature-dependent switch comprises first and second stationary contacts and a temperature-dependent switching mechanism having a movable contact member and a temperature-dependent snap-action part, which transitions between geometric low- and high-temperature configurations based on a temperature of the switch. Switching the snap-action part from its geometric low- to high-temperature configuration moves the switching mechanism from a first to a second switching position and thereby opens the switch. A closing lock prevents the switch once having opened from closing again by keeping it in its second switching position. The closing lock comprises a fusible medium which melts when a melting temperature of the medium is exceeded, contacts, in a molten state, a part of the switching mechanism when it is in its second switching position, and solidifies again and thereby locks it in its second switching position when the temperature of the switch falls below the melting temperature of the medium again.

A temperature switch 1 includes first terminal unit 2 having a first terminal 5 and a first fixed contact 6, a switch body unit 3 including a bimetal element 22 in which both ends engage a movable plate 15 holding, via an tongue portion 17, first and second fixed contacts 6 and 8 arranged in an internal center portion of an insulation material 10 at prescribed intervals and also holding a movable contact 18 arranged above them, and a second terminal unit 4 having a second terminal 7 and the second fixed contact 8. The first terminal unit 2, the switch body unit 3, and the second terminal unit 4 are sequentially arranged in line. At an ambient temperature, the bimetal element 22 deforms into a convex shape in the contact direction so as to push out the tongue portion 17 and the movable contact 18 at the center of the convex shape, and the movable contact 18 is closed with respect to the first and second fixed contacts 6 and 8 so that a current flows between the first and second terminals 5 and 7. At an ambient temperature equal to or higher than a prescribed value, the bimetal element 22 causes inversion to become concave in the contact direction, releases the biasing force of the spring property toward the space above the tongue portion 17, the movable contact 18 moves away from the first and second fixed contacts 6 and 8, and a current is cut off.

A heater-bimetal apparatus is disclosed. The heater-bimetal apparatus has a heating element having a first portion and a second portion, a bimetal element coupled to the heating element at a third portion between the first and second portions, and a support member coupled to the heating element at the third portion, the support member including registration surfaces adapted to be received in pockets formed in spaced portions of circuit breaker housing. Assemblies including the heater-bimetal apparatus and methods of assembly of heater-bimetal assemblies are provided, as are other aspects.

A heater-bimetal apparatus is disclosed. The heater-bimetal apparatus has a heating element having a first portion and a second portion, a bimetal element coupled to the heating element at a third portion between the first and second portions, and a support member coupled to the heating element at the third portion, the support member including registration surfaces adapted to be received in pockets formed in spaced portions of circuit breaker housing. Assemblies including the heater-bimetal apparatus and methods of assembly of heater-bimetal assemblies are provided, as are other aspects.

A varistor (50) comprising: a feed-through conductor (52) and a varistor disc (72) interposed between, and electrically connected to, conductor layers disposed on opposite surfaces of the varistor disc (72), the conductor layers being electrically isolated from one another; wherein the varistor disc (72) comprises a through aperture (60) through which the feed-through conductor extends; a first one of the conductor layers is electrically connected to the feed-through conductor; a second one of the conductor layers is, in normal use, permanently electrically connected to ground the varistor (50). This configuration enables one side of the disc (72) to be connected to the feed-through terminal, and the other side of the disc (72) to be connected to a ground plane, such as an earthed bulkhead of a wall or cabinet, via a metal plate forming part of the varistor (50) housing.