Patent ID: 6125582
Filing Date: 2000-10-03
Classification: E05D,E05Y

Abstract:
A counterbalance system for an upward acting door, the counterbalance system comprising: at least one rotatable drum and a flexible element for winding thereon, said flexible element being adapted for connection to said upward acting door for exerting counterbalance forces thereon, a torsion spring operably engaged with said drum and with a winder mechanism for adjusting a torsional force of said spring, said winder mechanism including a support plate operably engaged with a wall bracket of said counterbalance system by cooperating elements on said support plate and said wall brackets, whereby rotational movement between said wall bracket and said support plate in one direction provides for disconnection of said support plate with respect to said wall bracket and rotational movement between said support plate and said wall bracket in the opposite direction causes said support plate to forcibly engage said wall bracket, said cooperating elements on said support plate and said wall bracket being arranged to prevent further rotational movement between said wall bracket and said support plate in said opposite direction, said cooperating elements for engaging said support plate with said wall bracket include a first pair of spaced apart tab members formed on said support plate and registered in spaced apart slots formed in said wall brackets, wherein one of said tab members engages an edge of one of said slots and the other of said tab members engages an opposing edge of the other of said slots.