PURPOSE: To perform accurate positioning and facilitate teaching operation, by reducing manual operating force.

CONSTITUTION: To cause a robot to perform teaching, a jig is removed and a four-way shift valve 12 and a teaching lever 13 are attached together to a jig holding plate 11. Then, a solenoid valve 1 is energized to a position (a) to push the lever 13 forth. At that time, fluid is conducted to the top of a cylinder 8 through a valve 14, passages Ps and Cs and a uelve 18 to expand the cylinder 8 through. As a result, a vetical arm 1 is moved down to move a horizontal arm 2 forth in response to the motion of the lever 13. When the horizontal arm 2 is moved forth, the lever 13 is brough into a neutral hang position and the shift valve 12 is set into neutral position. Therefore, the arms can be lightly moved to desired position only by both the drive resistance of the horizontal arm 2 and the turning operation of the lever 13