| 摘要 |
<p>The invention relates to a drive arrangement for manoeuvering a generally vertically moveable door (12), the arrangement comprising at least one bendable door lifting element (50,60) which is connected to at least one of the two longitudinal side edges of the door (12). In order to enable the force required to manoeuvre the door (12) to be held substantially constant, or to vary only significantly over the full opening range of the door (12), particularly in the case of doors of the kind in which the force required to open or manoeuvre the door increases with the extent to which the door is opened, it is proposed in accordance with the invention that the door lifting element (50,60) has connected thereto an elongated, bendable counterbalance device (72), and in that the door lifting element (50,60) will function to move the counterbalance device (72) between an inactive position, in which it is generally horizontal, and an active position in which at least a part of the weight of the counterbalance device will exert a lifting force on the door (12) through the intermediary of the door lifting element (50,60). <IMAGE></p> |
