Screw jack

摘要

A screw jack which comprises a motor mounted in a housing which also houses a vertically mounted lifting screw assembly, a transmission unit for transmitting the output motion of the motor to the lifting screw assembly, and a limit switch means which is actuated by the screw assembly. The limit switch means includes an upper limit switch and a lower limit switch provided where the upward movement and the downward movement of the screw assembly are intended to be ended.