| 摘要 |
Garage door assemblies having a frame for receiving a door mounted for over head swinging movement and a spring element as an energy storing member which compensates for at least a part of the weight of the door. For the transfer of the force of the spring element to the door, there is provided a lever system including a lever capable of pivoting between a first position in which the spring force has a low leverage and a second position in which the spring force has an increased leverage sufficient to provide a turning moment capable of swinging the door. The lever is retained in its first position by a releasable locking device.
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