Patent ID: 6644375
Filing Date: 2003-11-11
Classification: E06B

Abstract:
A window blind comprising:a head rail; a bottom rail; a window covering extending between and operatively connected to the head rail and bottom rail; a lift cord extending between the bottom rail and the head rail; a cord spool rotatably mounted in one of the head rail and the bottom rail, an end of the lift cord proximate the one of the head rail and the bottom rail being coupled to the cord spool; a spring motor operatively coupled to the cord spool, the spring motor being adapted to rotate the cord spool to wind the lift cord thereon when the bottom rail moves toward the top rail, wherein the spring motor biases the bottom rail toward the head rail; and a one way brake engaging a moving component of the window blind, wherein friction of the one way brake prevents rotation of the cord spool when the bottom rail is moved toward the head rail, and permits rotation of the cord spool when the bottom rail is moved away from the head rail.