Patent ID: 7360576

Claim:
An electric transmission module for window curtains having a winding wheel, driven by an electric motor, comprising: a winding wheel further including at least one first wheel and one second wheel, said first wheel and said second wheel being mounted along an output shaft of said electric motor coaxially and parallel to each other, said first wheel and said second wheel being each provided with a groove around the circumference thereof; a plurality of transmission strings, one of said transmission strings being wound around said first groove of said first wheel, another of said transmission strings being wound around said second groove of said second wheel; and a bracket for mounting said electric motor and a transmission set; whereby said electric motor rotates in a direction selected from a backward direction and a forward direction to urge a synchronic rotation in said winding wheel so that said transmission strings wound thereon are respectively released or drawn back at said first wheel and drawn back or released at said second wheel, causing a curtain set to open or to close; and.