| 摘要 |
<p>An improved up-and-down pulley device for suspending height adjustable lamps or any other article requiring a regulated descent. The device comprises an adjustable friction system for the lamp descent, wherein the suspension wire winding drum is free to rotate in the wire return or rewinding direction, while its rotation, around a central stationary axis, is braked and regulated by the friction system in the direction of wire unwinding and therefore of lamp descent, rotation being controlled by a ratchet wheel of special structure. The device has a silent, precise and adjustable operation and a compact, sturdy structure comprising a limited number of elements.</p> |
