| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric heater suppressing electromagnetic waves generated from a heating element by passing currents through a first heating wire and a second heating wire in mutually opposite directions, and securing safety when either one of the first heating wire and the second heating wire becomes a partially disconnected state. SOLUTION: In the electric heater, the first heating wire 1 and the second heating wire 2 are serially connected, and currents of mutually opposite directions flow through the first heating wire 1 and the second heating wire 2. It is equipped with a malfunction detection circuit 9 detecting that either one of the first heating wire 1 or the second heating wire 2 has become a partially disconnected state on the basis of a comparison result of a voltage between an input terminal T1 and an input terminal T3, and a voltage between an input terminal T2 and the input terminal T3, and a breaker 10 breaking energization to a serial connection body of the first heating wire 1 and the second heating wire 2 when the malfunction detection circuit 9 detects that either one of the first heating wire 1 and the heating wire 2 has become a partially disconnected state. COPYRIGHT: (C)2009,JPO&INPIT
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