The present invention provides a protection device which provides a greater degree of freedom in a disposition of the bimetal switch as well as be able to more accurately control an actuation of the bimetal member of the bimetal switch. The protection device characterized in that the device comprises a bimetal switch wherein a first PTC member and a bimetal member are connected electrically in parallel with each other; and a second PTC member; and the bimetal member is disposed to be actuated by tripping of the second PTC member.

The present invention provides a protection device which provides a greater degree of freedom in a disposition of the bimetal switch as well as be able to more accurately control an actuation of the bimetal member of the bimetal switch. The protection device characterized in that the device comprises a bimetal switch wherein a first PTC member and a bimetal member are connected electrically in parallel with each other; and a second PTC member; and the bimetal member is disposed to be actuated by tripping of the second PTC member.

A controllable circuit protector for power supplies with different voltages includes a first fuse and a second fuse connected in series to each other, a first heating unit, and at least one second heating unit in parallel to the first heating unit. A connected end of the first heating unit is electrically connected to a series-connected node between the first fuse and the second fuse, and a free end thereof forms a control terminal. When a load is irregular, the control terminal is connected to a ground terminal through a switch. For power supplies with different voltages, the effective resistance of the first heating unit and a part of the at least one second heating unit not melting is altered without causing drastic change arising from voltage variation to the total heating power, and the first fuse or the second fuse can duly melt down to protect the load.

RF commutator including: a phase change material (7) arranged between a first conducting element (2) and a second conducting element (4), means of heating (11, 13) the phase change material provided with a first electrode (11) and a second electrode (13), the means of heating being capable of modifying the state of the phase change material (7) by injection of an electrical activation signal between the first electrode and the second electrode, at least one given electrode (11, 13) among the first electrode (11) and second electrode (13) comprising a conducting part (15a) arranged between the first conducting element (2) and the second conducting element (4), zones of the phase change material being laid out between the first conducting element (2) and the second conducting element (4) and being arranged on either side of this conducting part (15a).

RF commutator including: a phase change material (7) arranged between a first conducting element (2) and a second conducting element (4), means of heating (11, 13) the phase change material provided with a first electrode (11) and a second electrode (13), the means of heating being capable of modifying the state of the phase change material (7) by injection of an electrical activation signal between the first electrode and the second electrode, at least one given electrode (11, 13) among the first electrode (11) and second electrode (13) comprising a conducting part (15a) arranged between the first conducting element (2) and the second conducting element (4), zones of the phase change material being laid out between the first conducting element (2) and the second conducting element (4) and being arranged on either side of this conducting part (15a).

The object of the present invention is to provide a protection device capable of sufficiently suppressing the occurrence of arc at the time of activation with large rated voltage and rated current, as well as capable of fully opening the circuit. The present invention provides a protection device comprising: (i) a protection component comprising a first thermal fuse and a resistive body, the resistive body being supplied with a current in an abnormal state to generate heat, the heat activating the first thermal fuse to cut off the current; (ii) a PTC component; and (iii) a second thermal fuse, the second thermal fuse being electrically connected in series to the PTC component, the first thermal fuse of the protection component being electrically connected in parallel to the PTC component and to the second thermal fuse, and the protection component being activated in the abnormal state so that the PTC component trips to generate heat, the heat blowing the second thermal fuse.

The object of the present invention is to provide a protection device capable of sufficiently suppressing the occurrence of arc at the time of activation with large rated voltage and rated current, as well as capable of fully opening the circuit. The present invention provides a protection device comprising: (i) a protection component comprising a first thermal fuse and a resistive body, the resistive body being supplied with a current in an abnormal state to generate heat, the heat activating the first thermal fuse to cut off the current; (ii) a PTC component; and (iii) a second thermal fuse, the second thermal fuse being electrically connected in series to the PTC component, the first thermal fuse of the protection component being electrically connected in parallel to the PTC component and to the second thermal fuse, and the protection component being activated in the abnormal state so that the PTC component trips to generate heat, the heat blowing the second thermal fuse.

A protective element includes: a rectangurarly shaped insulating substrate; a heat-generating element formed on the insulating substrate; first and second electrodes laminated on a surface of the insulating substrate; first and second connecting terminals provided on a back surface of the insulating substrate and being continuous with the first and second electrodes; a heat-generating element extracting electrode provided on a current path between the first and the second electrodes and electrically connected to the heat-generating element; and a meltable conductor laminated on a region extending from the heat-generating element extracting electrode to the first and second electrodes and to be melted by heat to interrupt the current path between the first electrode and the second electrodes; wherein at least one of the corner portions of the insulating substrate is chamfered.

A protective element includes: a rectangurarly shaped insulating substrate; a heat-generating element formed on the insulating substrate; first and second electrodes laminated on a surface of the insulating substrate; first and second connecting terminals provided on a back surface of the insulating substrate and being continuous with the first and second electrodes; a heat-generating element extracting electrode provided on a current path between the first and the second electrodes and electrically connected to the heat-generating element; and a meltable conductor laminated on a region extending from the heat-generating element extracting electrode to the first and second electrodes and to be melted by heat to interrupt the current path between the first electrode and the second electrodes; wherein at least one of the corner portions of the insulating substrate is chamfered.

Disclosed is an SMD micro mixed fuse with a thermal fuse function that stably operates at high voltage surges and can interrupt electrical current at a predetermined temperature. The SMD micro mixed fuse includes: a fuse substrate provided with a first electrode and a second electrode; a variator layer formed on a front surface of the fuse substrate; a first contact terminal and a second contact terminal respectively arranged at a first side and a second side of a front surface of the varistor layer and respectively connected to the first electrode and the second electrode; at least one thermal fuse that is arranged on the front surface of the variator layer, is not connected to the first and second contact terminals, but is connected to the fuse substrate; and a fusible element that is wire-bonded to the first and second contact terminals and is not connected to the thermal fuse.