A thermal fuse for an electrical circuit is described, with a contact arm by way of which two electrical conductors are electrically conductively connected to each other, wherein the connection of the contact arm to at least one of the two conductors is a soldered joint, which loses its strength when a activation temperature of the fuse is reached. In accordance with this disclosure a permanent magnet is provided, which generates a magnetic force, which lifts the contact arm from at least one of the two conductors as soon as the soldered joint loses its strength.

The invention relates to a triggered fuse for low-voltage applications for protecting devices that can be connected to a power supply system, in particular surge protection devices, consisting of at least one fusible conductor which is located between two contacts and is arranged in a housing, and also consisting of a trigger device for controlled disconnection of the fusible conductor in the event of malfunctions or overload states of the respective connected device, wherein an arc quenching medium is introduced into the housing. By way of example, an arc quenching medium-free region is formed in the housing such that the at least one fusible conductor is exposed, and a mechanical disconnection element can be introduced into the arc quenching medium-free region via an access point in the housing in order to mechanically destroy the at least one fusible conductor depending on the trigger device, and independently of its melting integral.

A method of manufacturing a control device suitable for use in a vehicle includes providing a housing, a circuit board, and thermal fuse. A first contact of the fuse is soldered at the circuit board at a first solder joint and a second contact is soldered at the circuit board at a second solder joint. During assembly of the circuit board at the housing, an engaging tab of the thermal fuse engages the housing whereby the housing urges the engaging tab and the first contact of the thermal fuse in a direction away from a surface of the circuit board. When the control device is assembled and in use, and when a temperature exceeds a threshold temperature so that the first solder joint at the first contact sufficiently melts, the first contact moves away from the circuit board to break the electrical connection at the first solder joint.

An arc-preventing fast-breaking surge protection device is disclosed. In one of implement, surge protection device includes an arc-preventing assembly consisted of an arc-preventing catapult and an elastic element, comprising a voltage sensitive assembly, a response switch assembly, a thermosensitive element, an inner shell and an outer cover. The voltage sensitive assembly is tightly coupled with the response switch assembly. When the instantaneous surge voltage in circuits causes the voltage sensitive assembly to continuously heat up due to the fault short-circuit current, the response switch assembly causes the arc-prevent assembly to be catapulted and separated by the thermal coupling response of the thermosensitive element, meanwhile the response switch assembly is conceal by the arc-preventing assembly, thus preventing the arc generated when the switch is s catapulted and separated from forming a short-circuit and an overload, thus effectively avoiding fire and explosion hazards and further preventing secondary damage of electronic devices.

An arc-preventing fast-breaking surge protection device is disclosed. In one of implement, surge protection device includes an arc-preventing assembly consisted of an arc-preventing catapult and an elastic element, comprising a voltage sensitive assembly, a response switch assembly, a thermosensitive element, an inner shell and an outer cover. The voltage sensitive assembly is tightly coupled with the response switch assembly. When the instantaneous surge voltage in circuits causes the voltage sensitive assembly to continuously heat up due to the fault short-circuit current, the response switch assembly causes the arc-prevent assembly to be catapulted and separated by the thermal coupling response of the thermosensitive element, meanwhile the response switch assembly is conceal by the arc-preventing assembly, thus preventing the arc generated when the switch is s catapulted and separated from forming a short-circuit and an overload, thus effectively avoiding fire and explosion hazards and further preventing secondary damage of electronic devices.

The present invention relates to a multistage fuse, and more particularly, to a multistage fuse including: a fuse module including a first fuse bar formed in a bar shape as a conductive member; a melted portion which supports the first fuse bar and is melted when overcurrent flows; and a second fuse bar which supports the melted portion; and a contact terminal which contacts the first fuse bar by elastic force, in which when the overcurrent flows on the melted portion, the melted portion is melted to disconnect the first fuse bar and the contact terminal.

The present invention relates to a multistage fuse, and more particularly, to a multistage fuse including: a fuse module including a first fuse bar formed in a bar shape as a conductive member; a melted portion which supports the first fuse bar and is melted when overcurrent flows; and a second fuse bar which supports the melted portion; and a contact terminal which contacts the first fuse bar by elastic force, in which when the overcurrent flows on the melted portion, the melted portion is melted to disconnect the first fuse bar and the contact terminal.

The present invention provides a heat destructive disconnecting switch, which is composed of a first conductive member, a second conductive member, a movable conductive member, an overheating destructive member, an operating component, and a second elastic member. The movable conductive member enables conducting electricity to the first conductive member and the second conductive member. The overheating destructive member butts against a limiting member, which causes a first elastic member to be compressed to between a contact member and the overheating destructive member, thereby providing the first elastic member with a first elastic force and providing the second elastic member with a second elastic force. When the overheating destructive member is destructed due to overheating, the first elastic force is smaller than the second elastic force, which causes the movable conductive member to disconnect the first conductive member from the second conductive member, thereby achieving a protective effect from overheating.

The present invention proposes a protection device which has a large rated voltage and a large rated current, which is capable of sufficiently suppressing arc generation during activation, and which is also capable of providing suitable protection against overcurrent due to short circuiting or the like of a main circuit. The protection device of the present invention includes (i) a protection element which includes a first thermal fuse and a resistor, and in which the resistor generates heat as a result of current passing through the resistor when there are abnormalities, and the first thermal fuse is activated due to this heat and interrupts the current, (ii) a PTC element and a second thermal fuse which are electrically connected in parallel to the first thermal fuse and which are electrically connected in series to each other, and (iii) a current fuse which is electrically connected in series to the first thermal fuse.

The present invention proposes a protection device which has a large rated voltage and a large rated current, which is capable of sufficiently suppressing arc generation during activation, and which is also capable of providing suitable protection against overcurrent due to short circuiting or the like of a main circuit. The protection device of the present invention includes (i) a protection element which includes a first thermal fuse and a resistor, and in which the resistor generates heat as a result of current passing through the resistor when there are abnormalities, and the first thermal fuse is activated due to this heat and interrupts the current, (ii) a PTC element and a second thermal fuse which are electrically connected in parallel to the first thermal fuse and which are electrically connected in series to each other, and (iii) a current fuse which is electrically connected in series to the first thermal fuse.