Up-and-over garage door - has electric motor drive with chain to raise pivoted arms, and door counterbalanced by spring strut

摘要

The lower edge of the door leaf is located by rollers running in vertical guides secured to the door frame. An electric motor (15) with a reduction gear, drives a transverse shaft with a sprocket (19) at each end. The chain (21) driven by thesprocket (19) passes over three further wheels (23, 25, 26) with fixed mountings. The chain actuates the arm (33) which has a fixed pivot (27) at the end and is pivoted on the door plate at the other (13). The door is counterbalanced by a spring strut (9) and in its open position is supported in a ceiling mounted guide (35).