| 摘要 |
<p>A torsion spring counterbalancing assembly (10) for a downwardly moveable door (eg. a garage door) has an elongate counterbalance shaft (12) rotatable about its elongate axis (X-X), a torsion spring (14) coiled around the counterbalance shaft (12), and an adjuster (16) rotatably mounted on the counterbalance shaft (12). The torsion spring (14) is secured at one end (18) to the counterbalance shaft (12) and is secured at its other end (20) to the adjuster (16). The adjuster (16) permits adjustment of tension in the torsion spring (14) and includes a gripper member (26) that grips the counterbalance shaft (12) and prevents rotation of the adjuster (16) about the counterbalance shaft (12) in the absence of application of an external driving force to said adjuster (16). A moveable actuator member (30), which can be in form of a clip, is included for causing selective movement of the gripper member (26) in at least one direction.</p> |
