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.

The invention relates to a use of a high-voltage high-power fuse for securing direct current transmission, wherein the direct voltage of the direct current and/or the rated voltage of the high voltage fuse (1) is greater than 4 kV.

A high-voltage fusing apparatus includes a current fuse, a temperature fuse, and a current-carrying fuse. The current fuse is connected in series with the temperature fuse, and a series branch of the current fuse and the temperature fuse is connected in parallel with the current-carrying fuse. A resistance value of the current-carrying fuse is less than a resistance value of the current fuse, and a fusing temperature of the current-carrying fuse is lower than a fusing temperature of the temperature fuse. The high-voltage fusing apparatus can cut off a high-voltage circuit quickly, and effectively protect the high-voltage heating circuit from overheating.

A high-voltage fusing apparatus includes a current fuse, a temperature fuse, and a current-carrying fuse. The current fuse is connected in series with the temperature fuse, and a series branch of the current fuse and the temperature fuse is connected in parallel with the current-carrying fuse. A resistance value of the current-carrying fuse is less than a resistance value of the current fuse, and a fusing temperature of the current-carrying fuse is lower than a fusing temperature of the temperature fuse. The high-voltage fusing apparatus can cut off a high-voltage circuit quickly, and effectively protect the high-voltage heating circuit from overheating.

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.

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.

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 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 protective element includes a fuse element, a movable member, a concave member, and a press. The fuse member includes, a first end, a second end, and a cut part positioned between the first end and the second end. The fuse element is energized in a first direction from the first end to the second end. The movable member and the concave member are disposed facing each other such that the cut part is interposed therebetween. The press applies a force to the movable member in a pressing direction in which a distance between the movable member and the concave member shortens. At a temperature at or above a softening temperature of the fuse element, the cut part is cut by the force of the press.