A temperature-sensitive pellet type thermal fuse having a cylindrical metal case (11), a first lead (1) fixedly installed and insulated from the case (11) and a second lead (2) electrically connected to the case (11). A temperature-sensitive pellet (12) is installed by melting inside the case (11) and has a variable height. A moving terminal (16) is elastically coupled by a first spring (17) to the temperature-sensitive pellet (12) and an activating member (15) moves in a height decrease direction of the temperature-sensitive pellet (12) by an elastic repulsive force of a second spring (18). When the temperature-sensitive pellet (12) is melted and thereby is reduced in height, a first moving contact (16b) of the moving terminal (16) is separated from a first contact (1a) of the first lead (1).

A temperature-sensitive pellet type thermal fuse having a cylindrical metal case (10) with one end electrically connected to a first lead (L1) and a second lead (L2) installed on the other end via an insulating bushing (50). A temperature-sensitive pellet (30) on a spring (13) is in an inner space (S1) of the case (10). A switch terminal (40) has an upper surface (42) electrically connected to the second lead (L2) by an elastic force of the spring (13). A contact terminal piece (41) extends from the upper surface (42) to contact the inner wall surface (11) of the case 10. An activating member operates when the temperature-sensitive pellet (30) is reduced in height to a predetermined level or less, and releases contact between the contact terminal piece (41) and the case (10) to cut off an electrical connection between the first lead (L1) and the second lead (L2).

A temperature-sensitive pellet type thermal fuse having a cylindrical metal case (10) with one end electrically connected to a first lead (L1) and a second lead (L2) installed on the other end via an insulating bushing (50). A temperature-sensitive pellet (30) on a spring (13) is in an inner space (S1) of the case (10). A switch terminal (40) has an upper surface (42) electrically connected to the second lead (L2) by an elastic force of the spring (13). A contact terminal piece (41) extends from the upper surface (42) to contact the inner wall surface (11) of the case 10. An activating member operates when the temperature-sensitive pellet (30) is reduced in height to a predetermined level or less, and releases contact between the contact terminal piece (41) and the case (10) to cut off an electrical connection between the first lead (L1) and the second lead (L2).

A high breaking capacity chip fuse including a bottom insulative layer, a first intermediate insulative layer, a second intermediate insulative layer, and a top insulative layer disposed in a stacked arrangement in the aforementioned order, a fusible element disposed between the first and second intermediate insulative layers and extending between electrically conductive first and second terminals at opposing longitudinal ends of the bottom insulative layer, the first intermediate insulative layer, the second intermediate insulative layer, and the top insulative layer, wherein the first and second intermediate insulative layers are formed of porous ceramic.

A high breaking capacity chip fuse including a bottom insulative layer, a first intermediate insulative layer, a second intermediate insulative layer, and a top insulative layer disposed in a stacked arrangement in the aforementioned order, a fusible element disposed between the first and second intermediate insulative layers and extending between electrically conductive first and second terminals at opposing longitudinal ends of the bottom insulative layer, the first intermediate insulative layer, the second intermediate insulative layer, and the top insulative layer, wherein the first and second intermediate insulative layers are formed of porous ceramic.

A compact, high breaking capacity fuse that includes a top and bottom insulative layer and a single piece fusible element disposed between the top and bottom insulative layer. The top and bottom insulative layers include cavities that are aligned at assembly to form a chamber in which a fusible element portion of the single piece fusible element is disposed. The single piece fusible element additionally includes terminal portions that extend along outer surfaces of the top and bottom insulative layers.

A compact, high breaking capacity fuse that includes a top and bottom insulative layer and a single piece fusible element disposed between the top and bottom insulative layer. The top and bottom insulative layers include cavities that are aligned at assembly to form a chamber in which a fusible element portion of the single piece fusible element is disposed. The single piece fusible element additionally includes terminal portions that extend along outer surfaces of the top and bottom insulative layers.

A fuse and a production method therefor. The fuse comprises upper and lower insulating layers (2) provided with end electrodes (4), and a fuse body (1) between the upper and lower insulating layers (2). The fuse further comprises a functional layer (3) provided between the fuse body (1) and the insulating layers (2). The functional layer (3) comprises a base material (32) and an arc extinguishing material (31) uniformly or substantially uniformly distributed in the base material (32); the arc extinguishing material (31) comprises a sealed hole; the base material (32) comprises low-temperature co-fired ceramic powder, aerosol silicon oxide, silicon oxide, inert resin, phosphoric acid, and phosphate ester polyester; the content of the arc extinguishing material (31) is 1-50 wt %. The fuse overcomes the shortcomings in the prior art of phenomena such as deformation, bending, and defects occurring to a fuse body (1) caused by the shrinkage mismatch of the fuse body (1) with a buffer layer and an arc extinguishing layer in a sintering process because there is no support, the flatness, consistency and integrity of the fuse body (1) are ensured, and the fuse characteristics and production efficiency are remarkably improved.

An improved electric circuit structure for short circuit protection is applicable to examining a device under test, comprising a circuit breaking element, a thermistor, a filtering and rectifying module and a capacitor. A first end of the circuit breaking element is connected to a power source. The filtering and rectifying module is connected to a second end of the circuit breaking element, a ground, a first end of the thermistor and a first end of the capacitor. A second end of the capacitor is connected to a second end of the thermistor. The capacitor is connected in parallel with the device under test. The circuit breaking element disclosed in the present invention is a ceramic tube fuse and forms an open circuit when the device under test forms a short circuit. Meanwhile, the ceramic tube fuse withstands voltage between its first and second end without generating any physical damage.

An improved electric circuit structure for short circuit protection is applicable to examining a device under test, comprising a circuit breaking element, a thermistor, a filtering and rectifying module and a capacitor. A first end of the circuit breaking element is connected to a power source. The filtering and rectifying module is connected to a second end of the circuit breaking element, a ground, a first end of the thermistor and a first end of the capacitor. A second end of the capacitor is connected to a second end of the thermistor. The capacitor is connected in parallel with the device under test. The circuit breaking element disclosed in the present invention is a ceramic tube fuse and forms an open circuit when the device under test forms a short circuit. Meanwhile, the ceramic tube fuse withstands voltage between its first and second end without generating any physical damage.