Vertically movable rolling door - is held in equilibrium in any position by coupled spring mechanism

摘要

The rolling door is movable in the vertical direction, being deflected in the transverse direction at one end. A spring mechanism (5-10) is coupled to the door (1), its tension being varied as the latter moves, so as to hold it in a state of equilibrium in virtually any position. Coupling can be by means of a pinion (5) rotated by door movement, and meshing with teeth formed in the door slats.