Patent ID: 7353857
Filing Date: 2008-04-08
Classification: E06B,F16G,Y10T

Abstract:
1. A blind operating system comprising in combination: a sprocket wheel for driving a driven blind member; a ball chain looped over the sprocket wheel and operatively engaging it; and a cover that is over at least a portion of the sprocket wheel and that is in contact with the ball chain; the chain having a plurality of balls which are spaced apart along the length of the chain and are interconnected by a plurality of intermediate chain members that extend along the length of the chain between adjacent balls; the system being characterized by at least one chain stopper, attached to the chain about an intermediate chain member between two adjacent balls, the chain stopper having a maximum cross-sectional size (MC stopper ) that is equal to or less than the size of the maximum cross-section of the balls (MC ball ) of the chain.