ELECTRIC MOTOR WITH HEAT SAFETY DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent fire accients of a motor due to thermal overload by providing an electric motor such as a commutator motor and a wound wire-rotor motor. SOLUTION: Isolation constants 50 on the ground are disposed at an interval outside a cylinder 32 of a brush 24 of an electric motor. When the brush 24 is heated up to the softening temperature of a plastic brush supporter 46, a brush spring 34 pushes the cylinder 32 outwards, to bring it into contact with the isolation contacts 50 to generate a short circuit to blow off the fuse in the electric motor.