| 摘要 |
<p>A tensioning assembly for a door system, which includes an upwardly acting door supported by a frame and connected to a counterbalance system having a counterbalance spring, the tensioning assembly including a rotatable tension plate coupled to the counterbalance spring and rotatable relative to the counterbalance spring, the tension plate being selectively moveable between a disengaged position where the tension plate is freely rotatable and an engag ed position where the tension plate is rotationally fixed to the frame; and a spring adapted to urge the tension plate toward the engaged position, whereb y when in the disengaged position the tension plate is rotatable to adjust tension in the counterbalance spring and the tension plate is returned to th e engaged position to maintain the tension.</p> |
