| 摘要 |
The present invention discloses a mechanism (100) particularly suitable for use with lifting systems of sectional doors comprising at least a pair of independent main bodies (120), each provided with a cavity (190) and conjugate profiles (130) operatively associated with one another formed on a portion of lateral surface of said main bodies (120). The remaining portion (140) of said lateral surface of said main bodies (120) is arranged for winding of lifting cables of said lifting systems; there is also a rotating shaft (150) for each main body (120) housed in said cavity (190); an elastic member (170) connected to said shaft (150) and to a surface (192) of said cavity (190); and an overrunning mechanism (180) operatively connected with said shaft (150). The disclosed mechanism more particularly comprises an elastic member (170) which is under full load when the sectional door is closed, and is fully released when the sectional door is fully open, and the relief curve of said elastic member (170) is proportional to the weight vertically exerted by said sectional door, said weight being variable along the vertical during the lifting operation of the door, the weight of the already lifted door portion being supported by horizontal guides (230) and no longer by said elastic member (170). |
