Patent ID: 8522852

Claim:
A window covering comprising: a head rail having a longitudinal axis; a weighted element; a window cover material connected between the head rail and the weighted element; a rotary axle placed in the head rail along the longitudinal axis; and a plurality of control modules placed in the head rail and coupled with the rotary axle at spaced-apart positions along the longitudinal axis, wherein each of the control modules includes: a housing; a winding drum pivotally assembled in the housing, wherein the winding drum includes a first and a second drum portion adapted to mount with the rotary axle, the first and second drum portions being formed integrally with the winding drum; a suspension cord having a first and a second end, the first end being connected with the first drum portion, and the second end extending outside the housing and being connected with the weighted element; and a spring connected with the second drum portion, the spring being operable to bias the winding drum and the rotary axle for rotation in a direction to wind the suspension cord around the first drum portion; wherein the rotary axle passes through the winding drum and the spring.