Patent ID: 11955259
Assignee: PROTERIAL, LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 1:
2. A multi-core cable, comprising:
a heat detection line comprising a twisted pair wire comprising a pair of heat detecting wires being twisted together, each heat detecting wire comprising a conductor and an insulator covering a periphery of the conductor, wherein the conductor is non-magnetic and comprises a copper alloy composed of a phosphor bronze consisting of 7 mass % or more and 9 mass % or less of Sn, and 0.03 mass % or more and 0.35 mass % or less of P and the balance being Cu and inevitable impurities with a tensile strength of 900 MPa or more;
a plurality of electric wires; and
a sheath covering the heat detection line and the plurality of electric wires together,
wherein a melting point of the insulator of the heat detection line is lower than a melting point of an insulator of each of the plurality of electric wires,
wherein when the insulators are softened or melted at a given temperature, the conductors of the pair of heat detecting wires move toward a center of the twisted pair wire and contact each other, by a force which allows the conductors to move closer to each other,
wherein the plurality of electric wires are spirally twisted around the heat detection line,
wherein the heat detection line closely contacts with the electric wires so that heat transfers from the electric wires to the heat detection line,
wherein the electric wires are pressed against the heat detection line and conductors of the heat detection line contact to each other when a temperature in the multi-core cable rises,
wherein the insulator of each of the electric wires is composed of a same material and a single layer,
wherein an outer diameter of the conductor is 0.5 mm or more and 1.0 mm or less, and
wherein a thickness of the insulator of the heat detection line is 0.1 mm or more and 0.3 mm or less.