PURPOSE: To facilitate advance and retract of a slide table, irrespective of installation height, by providing a driving roller which can rotate on a guide rail, and a motor which interlocks with a driving roller in the slide table.

CONSTITUTION: A pair of right and left motors are synchronously driven by the direction of a controller 35, and a driven roller 24 interlocks with the operation to rotate a driving roller 24 forward. Besides, a target slide table 20 is supported and guided by a guide rail 10 through a guide rail 21 and side guide rollers 22, 23 to protrude to the front part of a rack. As indicated with a virtual line, a magnet 32 reaches the position which faces a magnetic proximity switch 30 when the slide table 20 is withdrawn to a protruding limit position, and the magnetic proximity switch 30 is turned on to send a detected signal to the controller 35. With this constitution, the controller 35 stops the driving of both the motors automatically, and the slide table 20 stops at the protruding limit position where a side guide roller 23 comes into contact with a stopper plate 16.