An insulation device is disclosed. The insulation device is allowed to be assembled with a fuse tube device so as to form a load break fuse cutout fully closed. The insulation device comprises: a full-closed cylindrical insulator oriented vertically, a first cylindrical insulator oriented horizontally, a second cylindrical insulator oriented horizontally, a third cylindrical insulator oriented horizontally, a first electrical connection unit accommodated in the first cylindrical insulator, a second electrical connection unit accommodated in the second cylindrical insulator, a first arc extinguishing unit accommodated in the first cylindrical insulator, a second arc extinguishing unit accommodated in the second cylindrical insulator, and a mounting bracket connected to the full-closed cylindrical insulator. The full-closed cylindrical insulator, the first cylindrical insulator, the second cylindrical insulator, and the third cylindrical insulator are made integratedly so as to form a main insulation body of the insulation device.

A thermal cutoff at least includes a current-carrying fusible element having two ends connected to a first electrode and a second electrode. The current-carrying fusible element is provided in a closed cavity bounded by a housing having an opening at one end, a cover plate, and a sealant. The thermal cutoff further includes a first lead wire and a second lead wire each wrapped by an insulating sheath. One end of the first lead wire and one end of the second lead wire are electrically connected to the first electrode and the second electrode. The sealant is filled in the opening of the housing, covers an electrical joint between the first lead wire and a first electrode plate and an end of the first lead wire, and also covers an electrical joint between a second electrode plate and the second lead wire and an end of the second lead wire.

A fuse tube device is disclosed. The fuse tube device is allowed to be assembled with an insulation device so as to form a load break fuse cutout fully closed. The fuse tube comprises: an insulation housing, an accommodation tube, a first electrical connection unit, a second electrical connection unit, a conductive rod, a fuse element, a first conductive plate, a first cover, a second conductive plate, and a second cover. When assembling the fuse tube device with the insulation device, a first embedding member and a second embedding member of the insulation housing are embedded into a first terminal connecting opening and a second terminal connecting opening of the insulation device, such that the first electrical connection unit and the second electrical connection unit contact a first terminal connecting member and a second terminal connecting member of the insulation device, respectively.

A power fuse for protecting an electrical load subject to transient load current cycling events in a direct current electrical power system is provided. The power fuse includes at least one fuse element assembly that includes an elongated planar substrate, a plurality of fusible weak spots, and a conductor. The weak spots are formed on the substrate and are longitudinally spaced from one another on the substrate. The conductor is separately provided from the substrate and the weak spots. The conductor includes a solid elongated strip of metal having no stamped weak spot openings therein and therefore avoiding thermal-mechanical fatigue strain in the conductor when subjected to the transient load current cycling events. The solid elongated strip of metal includes coplanar connector sections that are mounted to respective ones of the weak spots and obliquely extending sections bent out of plane of the connector sections to extend above the substrate.

This protection element (100) has a fuse element (3), an insulating inorganic fibrous material (4) that is disposed in contact with or close to at least a part of the fuse element (3), and a case member (5) configured to enclose a part of the fuse element (3) and the insulating inorganic fibrous material (4).

An electrical fuse is provided. The electrical fuse includes a short circuit fusible element and a trigger element connected in series with the short circuit fusible element. The trigger element is chemically activated rather than mechanically activated to interrupt a predefined overload condition with a predetermined time delay.

In a chip fuse, a heat-storing layer is formed on an insulated substrate, a fuse film is formed on the heat-storing layer, and a protective film is formed on the fuse element section. The chip fuse includes surface electrode sections on both ends in the length direction of the chip fuse and a fuse element section between the surface electrode sections. In this chip fuse, a rectangular bank section is formed over the heat-storing layer and the surface electrode sections to surround the fuse element section, and a first protective layer is formed on the inner side of the bank section. In addition, during the bank formation process, a sheet-like photosensitive-group-containing material is laminated on the fuse element section, surface electrode sections, and heat-storing layer, and the sheet-like photosensitive-group-containing material is exposed to ultraviolet light and developed to form the rectangular bank section.

A high-voltage direct-current thermal fuse includes one or more fusible components each having two fusible alloy support arms, a fluxing agent, a fusing cavity, two pins, and an insulation block. Two fusible alloy support arms are arranged opposite, and the fusible component is U-shaped. The fusible component and the fluxing agent are sealed within the fusing cavity. The two pins are respectively connected to the two fusible alloy support arms. The insulation block is arranged between the two fusible alloy support arms and separates the two pins. A volume ratio of the fluxing agent to the fusing cavity is approximately 50% or less, preferably, 10%-50%. The number of the one or more fusible components is at least two, and the at least two fusible components are arranged separately. The thermal fuse can avoid the burst and quickly cut off the current, which provides effective thermal protection for a circuit.

A power fuse includes a housing, first and second conductive terminals extending from the housing, and at least one fatigue resistant fuse element assembly connected between the first and second terminals. The fuse element assembly includes at least a first conductive plate and a second conductive plate respectively connecting the first and second conductive terminals, and a plurality of separately provided wire bonded weak spots interconnecting the first conductive plate and the second conductive plate.

A power fuse for protecting an electrical load subject to transient load current cycling events in a direct current electrical power system is provided. The power fuse includes at least one fuse element assembly that includes one or more substrates, one or more sets of weak spots, and a conductor. The weak spots are formed on the substrates, and the substrates are longitudinally spaced apart from one another along the conductor. The conductor is separately provided from the substrate and the weak spots. The conductor includes one or more strips of metal having no stamped weak spot openings therein and therefore avoiding thermal-mechanical fatigue strain in the conductor when subjected to the transient load current cycling events. The conductor includes connector sections that are attached to respective ones of the sets of weak spots, and extending sections coupling the connector sections.