A metal housing or casing for a thermal fuse (i.e., a thermal cut-off device) that has a multilayer metal construction including a copper-based layer, a first nickel layer disposed on a first side of the copper-based layer and including an outer surface of the casing, a second nickel layer disposed on a second side of the copper-based layer opposite to the first side of the copper-based layer, and a single silver layer disposed only on the second nickel layer and comprising the inner surface of the casing.

The invention relates to a short-circuiting device for use in low-voltage and medium-voltage systems for the protection of property and persons, comprising: a switching element, which can be operated by the tripping signal of a fault detection device; two mutually opposite contact electrodes having power supply means, which contact electrodes can be brought into contact with an electrical circuit having connection points at different potential; furthermore, in at least one of the contact electrodes, a movable contact part, which is under mechanical preload and executes a movement to the further contact electrode with the assistance of spring force in the event of a short circuit; and a sacrificial element as a spacer between the contact electrodes, with an electrical connection between the sacrificial element and the switching element on the one hand and one of the contact electrodes on the other hand, in order to deliberately cause current-flow-induced thermal deformation or destruction of the sacrificial element. According to the invention, the movable contact part is in the form of a hollow cylinder which is closed on one side, and a spring for generating preload is inserted in the hollow cylinder. The hollow cylinder is movably guided in a complementary cutout in the first contact electrode, a sliding contact thus being formed. In the region of the base of the closed hollow cylinder, the cylinder wall of said hollow cylinder transitions into a cone at the outer circumference. Furthermore, a first pin-like extension, opposite to which a second pin-like extension insulated from the contact electrodes is situated, extends within the hollow cylinder, proceeding from the base. The sacrificial element, in the form of a bolt or screw, is arranged between the first and the second pin-like extension. A cutout, which has an internal cone and is matched to the external cone of the movable contact, is provided in the second contact electrode. The external cone and the internal cone form a bounce-free short-circuit contact region having frictional locking and interlocking connection on account of plastic deformation which occurs. Furthermore, according to the invention the switching element is designed as an auxiliary short-circuiter on the basis of an electric match.

The temperature sensitive pellet type thermal fuse includes a cylindrical case which has a first end and a second end, a temperature sensitive pellet, an insulating tube, a first lead which is inserted into the insulating tube and has an inner end serving as a contact portion, a movable contact which is electrically connected to the cylindrical case, a weak compression spring, a strong compression spring, and a second lead which is disposed on the second end of the cylindrical case. The movable contact includes a projecting contact portion which is provided at a central part of the movable contact, and the projecting contact portion and the contact portion of the first lead are in contact with each other inside the insulating tube.

The invention relates to a short-circuiting device for use in low-voltage and medium-voltage systems for the protection of property and persons, comprising: a switching element, which can be operated by the tripping signal of a fault detection device; two mutually opposite contact electrodes having power supply means, which contact electrodes can be brought into contact with an electrical circuit having connection points at different potential; furthermore, in at least one of the contact electrodes, a movable contact part, which is under mechanical preload and executes a movement to the further contact electrode with the assistance of spring force in the event of a short circuit; and a sacrificial element as a spacer between the contact electrodes, with an electrical connection between the sacrificial element and the switching element on the one hand and one of the contact electrodes on the other hand, in order to deliberately cause current-flow-induced thermal deformation or destruction of the sacrificial element. According to the invention, the movable contact part is in the form of a hollow cylinder which is closed on one side, and a spring for generating preload is inserted in the hollow cylinder. The hollow cylinder is movably guided in a complementary cutout in the first contact electrode, a sliding contact thus being formed. In the region of the base of the closed hollow cylinder, the cylinder wall of said hollow cylinder transitions into a cone at the outer circumference. Furthermore, a first pin-like extension, opposite to which a second pin-like extension insulated from the contact electrodes is situated, extends within the hollow cylinder, proceeding from the base. The sacrificial element, in the form of a bolt or screw, is arranged between the first and the second pin-like extension. A cutout, which has an internal cone and is matched to the external cone of the movable contact, is provided in the second contact electrode. The external cone and the internal cone form a bounce-free short-circuit contact region having frictional locking and interlocking connection on account of plastic deformation which occurs. Furthermore, according to the invention the switching element is designed as an auxiliary short-circuiter on the basis of an electric match.

The invention relates to a thermally triggered, mechanical switching device, consisting of a heat-sensitive means and a mechanical force-storage means, wherein the heat-sensitive means blocks or unblocks the movement path of a switching piece; furthermore, the switching piece is preloaded and held by the mechanical force-storage means, and comprising a housing that accommodates the aforementioned means. According to the invention, the housing is designed as a cartridge-shaped shell which receives a plunger in the interior thereof, which plunger is mounted in a movable manner through a first end-side opening in the housing and is supported against a fusible shaping part under pretension, wherein the fusible shaping part is arranged so as to cover a second opening, which is located opposite the first end-side opening, in such a way that, when the melting temperature of the fusible shaping part is reached, said fusible shaping part is displaced by the plunger and the plunger takes on a changed position.

The temperature sensitive pellet type thermal fuse includes a cylindrical case which has a first end and a second end, a temperature sensitive pellet, an insulating tube, a first lead which is inserted into the insulating tube and has an inner end serving as a contact portion, a movable contact which is electrically connected to the cylindrical case, a weak compression spring, a strong compression spring, and a second lead which is disposed on the second end of the cylindrical case. The movable contact includes a projecting contact portion which is provided at a central part of the movable contact, and the projecting contact portion and the contact portion of the first lead are in contact with each other inside the insulating tube.

A thermal fuse includes a casing wall configured to transfer heat energy generated exterior to the casing wall to a thermally activated device disposed in an interior of the casing wall. The thermally activated device is configured for activation at a preselected temperature. The casing wall includes a coating layer disposed on an adjacent layer. The coating layer forms an outermost surface of the casing wall and has an emissivity greater than the adjacent layer of the casing wall.

The invention relates to a thermally triggered, mechanical switching device, consisting of a heat-sensitive means and a mechanical force-storage means, wherein the heat-sensitive means blocks or unblocks the movement path of a switching piece; furthermore, the switching piece is preloaded and held by the mechanical force-storage means, and comprising a housing that accommodates the aforementioned means. According to the invention, the housing is designed as a cartridge-shaped shell which receives a plunger in the interior thereof, which plunger is mounted in a movable manner through a first end-side opening in the housing and is supported against a fusible shaping part under pretension, wherein the fusible shaping part is arranged so as to cover a second opening, which is located opposite the first end-side opening, in such a way that, when the melting temperature of the fusible shaping part is reached, said fusible shaping part is displaced by the plunger and the plunger takes on a changed position.

The invention relates to a short-circuiting device for use in low-voltage and medium-voltage systems for protecting parts and personnel, comprising a switching element which can be operated by the tripping signal of a fault detection device, two mutually opposite contact electrodes having power supply means, wherein contact can be made with said contact electrodes at an electrical circuit having connections at different potentials, furthermore, in at least one of the contact electrodes, a moving contact part which is under mechanical prestress and executes a movement to the further contact electrode in a manner assisted by spring force in the event of a short circuit, a sacrificial element as spacer between the contact electrodes and also having an electrical connection between the sacrificial element and the switching element on the one hand and one of the contact electrodes on the other hand, in order to cause current flow-induced thermal deformation or destruction of the sacrificial element in a targeted manner. According to the invention, the moving contact part is in the form of a hollow cylinder which is closed on one side and a spring for generating prestress is used in the hollow cylinder. The hollow cylinder is guided in a movable manner in a complementary cutout in the first contact electrode so as to form a sliding contact. In the region of the base of the closed hollow cylinder, the cylinder wall of said hollow cylinder is configured to turn into a cone on its outer circumferential side. Furthermore, starting from the base, a first pin-like extension which is situated opposite a second pin-like projection which is insulated from the contact electrodes is arranged in the interior of the hollow cylinder, wherein the sacrificial element, in the form of a bolt or screw, is arranged between the first and the second pin-like projection. A cutout which is matched to the external cone of the moving contact and has an internal cone is provided in the second contact electrode, wherein the external cone and internal cone form a bounce-free short-circuit contact region with a force-fitting and interlocking connection on account of the plastic deformation which occurs.

A temperature fuse assembly for a high-power DC circuit is provided. The temperature fuse assembly includes a case extending from a first case end to a second case end and an isolated lead projecting from the second case end. A bushing electrically isolates the isolated lead from the case. A high-gauge wire is electrically connected to the case at a first wire end and electrically connected to the isolated lead at a second wire end. A portion of the high-gauge wire is helically wound about an exterior of the bushing. When a temperature of the temperature fuse assembly exceeds a threshold temperature, the temperature fuse assembly is configured to conduct a DC current of the high-power DC circuit through the high-gauge wire. The high-gauge wire is configured to melt under a load of the DC current and interrupt the high-power DC circuit.