| 摘要 |
PURPOSE:To surely stop the electrification of a motor before it causes a burn or the like, by providing a shape memory alloy, which deelectrifies the motor by the sensing action of temperature, in the field of a motor part. CONSTITUTION:A bracket 35 mounts a field 37, winding a field winding 36 to be mounted, and a brush holder 39, holding a brush 38, while arranges an armature 40 so as to surround it by the field 37, and an armature winding 41 is connected to a commutator segment 42. A shape memory alloy piece 43, internally provided in the field 37, forms one end of the piece 43 to be protruded in a side of the brush 38 and formed in an L-shaped piece 43a, while a stopper member 47 for stopping the L-shaped piece 43a is mounted to be attached to the brush holder 39. In this way, destruction of a motor can be prevented before its occurrence by transmitting heat to the shape memory alloy piece 43 and deforming the L- shaped piece 43a so as to separate the brush 38 from the commutator segment 42 when an impeller 32 is locked causing the flow of an overcurrent. |
