Electromagnetic clutch-controlled electric blind

1. An electromagnetic clutch-controlled electric blind comprising:

a blind body, said blind body having a headrail and a slat set, said headrail having an internal holding chamber, said slat set having a plurality of slats;

a power drive, said power drive comprising only a single motor, and at least one first electromagnetic clutch controlled by a single receiver to actuate said first electromagnetic clutch between a first position engaged to said single motor and a second position disengaged from said single motor;

an amplitude modulation set, said amplitude modulation set having a spindle engaged to said single motor for rotation with said single motor to lift/lower said slats to a desired elevation;

a frequency modulation set, said frequency modulation set having a spindle engaged to said single motor through said first electromagnetic clutch when said first electromagnetic clutch is actuated to be in said first position to rotate and control a tilting angle of said slats.

2. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said motor is a single side reversible motor.

3. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said motor is a double side reversible motor.

4. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein the spindle of said amplitude modulation set is engageable to said motor through at least one second electromagnetic clutch controlled by the signal receiver to actuate said second between a first position engaged to said single motor and a second position disengaged from said single motor.

5. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said power drive further comprises a transmission gear set coupled between said motor and said amplitude modulation set.

6. The electromagnetic clutch-controlled electric blind as claimed in claim 4 , further comprising an amplitude modulation detection unit mounted in the internal holding chamber of said headrail which stops said motor when said amplitude modulation detection unit lifts/lowers said slats to a limit position.

7. The electromagnetic clutch-controlled electric blind as claimed in claim 4 , further comprising a frequency modulation detection unit mounted in the internal holding chamber of said headrail and adapted to stop said motor when said frequency modulation set tilted said slats to a limit angular position.

8. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said power drive further comprises a signal transmitter which transmits one of a series of control signals, said signal receiver electrically connected to said single motor and said at least one first or second electromagnetic clutch and adapted to receive a control signal from said signal transmitter and to switch on/off said at least one first or second electromagnetic clutch and said motor subject to the control signal received, and a battery electrically connected to said motor and said at least one first or second electromagnetic clutch to provide the necessary working power.

9. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said amplitude modulation set further comprises two holders fixedly mounted in the internal holding chamber of said headrail, two bobbins respectively mounted in said holders and fixedly mounted on the spindle of said amplitude modulation set for synchronous rotation, and two amplitude modulation lift cords, said amplitude modulation lift cords connected in parallel between said the bobbins of said amplitude modulation set and said bottom rail.

10. The electromagnetic clutch-controlled electric blind as claimed in claim 1 , wherein said frequency modulation set further comprises a transmission gear set fixedly connected to the spindle of said frequency modulation set and coupled to said motor through said at least one first electromagnetic clutch, two wheels respectively mounted on the spindle of said frequency modulation set for synchronous rotation, and two frequency modulation lift cords respectively wound round the wheels of said frequency modulation set, said frequency modulation lift cords each having two ends respectively connected in parallel to said slats and said bottom rail.

11. The electromagnetic clutch-controlled electric blind as claimed in claim 4 , wherein said amplitude modulation set is engaged to said single motor through said second electromagnetic clutch to lift/lower said slats to the described elevation.

12. An electromagnetic clutch-controlled electric blind comprising:

a blind body, said blind body having a headrail and a slat set, said headrail having an internal holding chamber, said slat set having a plurality of slats;

a power drive, said power drive comprising only a single motor, and an electromagnetic clutch controlled by a single receiver to actuate said electromagnetic clutch between a first position engaged to said single motor and a second position disengaged from said single motor;

an amplitude modulation set, said amplitude modulation set having a spindle engaged to said single motor and said electromagnetic clutch for rotation with said single motor to lift/lower said slats to a desired elevation when said electromagnetic clutch is actuated to be in said first position;

a frequency modulation set, said frequency modulation set having a spindle engaged to said single motor clutch to control a tilting angle of said slats when the signal receiver actuates said single motor.