Counter-balance mechanism for up-and-over garage door - has gas spring which holds door in closed or in open positions

摘要

An up-and-over garage door has a roller (3) attached to each side near the upper edge of the door. This roller runs on an overhead rail (4). The weight of the door is counterbalanced by a gas spring (11) which acts on one end of a pivoted arm (5) the other end of which is pivoted to the lower end of the door. The geometry of the arm and gas spring is such that the spring applies a force which holds the door in its fully open position and also applies a force when the door is closed which holds the door in that position. USE - Up-and-over garage door.