摘要 |
A motor assembly for ceiling fans includes a top cover having a plurality of protrusions extending from a top thereof, a bottom cover and a ring-shaped member connected between the top cover and the bottom cover so as to form a case. A shaft rotatably extends through the top cover and the bottom cover. A stator is fixed to the shaft and located in the case, and a permanent magnet is fixed to an inner periphery of the ring-shaped member. A light detection device is connected to the frame and includes a light detection member. A circuit board is located in the light detection device. The protrusions pass through the light detection member to block a light beam emitted from the light detection member to activate the light detection member to send a signal to the circuit board to count the revolution of the shaft.
|