摘要 |
A motor-driven curtain assembly includes a drive shaft mounted rotatably in a top rail, a motor for driving rotatably the drive shaft, and a curtain unit coupled to the drive shaft for movement between closed and open positions. A motor-control device includes a driving circuit for enabling rotation of the motor in one of positive and negative directions under the control of a control unit, a current limiting circuit for limiting current flow from an external power source to the driving circuit when the motor is subjected to an increase in load resistance, and an over load detector for generating a control signal that is indicative of the amount of current flowing from the current limiting circuit to the driving circuit and that is provided to the control unit, thereby enabling the control unit to deactivate the driving circuit for stopping operation of the motor when overloading of the motor occurs.
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