摘要 |
A spreader unit for controlling a multi-legged stand is presented comprising a hub having a central axis and a plurality of arms hinged to the hub to swing in radial planes with respect to the hub axis. A control shaft is mounted in the hub for rotation about the axis with a reversible gear drive between the shaft and arms so that rotation of the shaft swings the arms with respect to the hub in unison and vice versa. A control for locking the shaft against rotation with respect to the hub is provided to hold the arms in required spread positions with respect to the hub. |