To obtain a highly reliable power converter capable of quickly detecting a fire by applying or sticking an overheat detecting material consisting of a substance causing the separation of particles by thermally decomposition when the temperature of each electric part exceeds a maximum using temperature.
Main circuit conductors 21a, 21b consisting of copper bar materials are mutually connected by clamping them by a bolt 23 and a nut 24. Since a current allowed to flow into the conductors 21a, 21b is large, the looseness of the connection part causes overheat by Joule heat due to contact resistance, and in an extreme case, the connection part is melted and an arc is generated, causing a fire. Thereby an overheat detection material 22 consisting of a substance causing the separation of particles by thermal decomposition when the temperature of the connection part exceeds a maximum using temperature in normal use is applied or stuck to the vicinity of the connection part. Since the maximum using temperature of the conductors 21a, 21b including the connection part does not exceed 100°C usually, the thermal decomposition temperature of the material 22 is set up to about 150 to 220°C, so that overheat can be detected before exerting the influence of the overheat upon other electric parts.
SHIRAHAMA HIDEFUMI
UEDA SHIGETA
YAMATO IKUO
| JPS5585572A | 1980-06-27 | |||
| JPS56133270A | 1981-10-19 |