Up and over garage door - has parallelogram linkage and diagonal spring between swing support on vertical track and inner leaf of door

摘要

The counter-balancing spring is for an up-and-over door. The door (2) is operated with a pair of horizontal rails (5) and roller (4), and a pair of vertical rails (3). To balance the door in cases of sudden removal of the operating force, either manual or motor, a parallelogram linkage (13) with a diagonal spring (15) is arranged between the vertical track slide (9) and the rear of the door panel. USE/ADVANTAGE - Door is balanced at all phases of operation.