Roller shutter security locking mechanism - has spring strip fastening chain to spindle, and link blocked at obtuse angle

摘要

A chain hung on the winding spindle, has links foldable together against the spindle, but blocking at an obtuse angle the other way, and engaged by a spring element, in the roller shutter or large rolling door. The chain (a) is attached to the spindle (2) by a spring strip (5), longer than the distance (7) of the spindle from the inside edge of the shutter case above the guiderails, but less than this plus spindle dia. The chain link (10') attached to the shutter screen is blocked in the folding direction at an angle less than 180 deg. to the plane of the guide rails (22). The locking mechanism induces load release from spindle and case front, from forces incurred when the screen by an intruder.