Patent ID: 9159601
Filing Date: 2015-10-13
Classification: B25J,H01L

Abstract:
1. A workpiece transfer apparatus comprising: a stationary base; an elevation base vertically movably supported by the stationary base; a first arm and a second arm each of which includes a base end and a distal end; a hand for holding a workpiece; and a hand driving mechanism for driving the hand for rotation, wherein: the base end of the first arm is supported on the elevation base such that the first arm is rotatable about a first vertical axis, the base end of the second arm is supported on the distal end of the first arm such that the second arm is rotatable about a second vertical axis, the hand is supported on the distal end of the second arm such that the hand is rotatable about a third vertical axis, the hand driving mechanism includes a motor and a transmission mechanism for transmitting rotational output of the motor to the hand, the motor is arranged in the first arm, and the transmission mechanism is arranged to extend in a region from an interior of the first arm through an interior of the second arm, and wherein the transmission mechanism comprises: a speed reducer for reducing rotation speed of an output shaft of the motor, the speed reducer being disposed right below the motor; an intermediate transmission shaft including a first end and a second end and arranged rotatably about the second vertical axis; an operation shaft including a first end and a second end and arranged rotatably about the third vertical axis; a first through a fourth pulleys; and a first and a second endless belts, the first pulley being attached to an output shaft of the speed reducer, the second pulley being attached to the first end of the intermediate transmission shaft, the first endless belt being wound around the first pulley and the second pulley, the third pulley being attached to the second end of the intermediate transmission shaft, the fourth pulley being attached to the first end of the operation shaft, the second endless belt being wound around the third pulley and the fourth pulley, and the second end of the operation shaft being connected to the hand, the first arm including a projecting portion projecting downward, wherein the first pulley, the second pulley and the first endless belt are arranged in the projecting portion.