| 摘要 |
PURPOSE:To detect a reversing error of a semiconductor-wafer transfer part by judging whether a reversing-position-detecting means has detected that the semiconductor-wafer transfer part is situated in a prescribed position during a prescribed time after the semiconductor-wafer transfer part has started a reversing operation. CONSTITUTION:A motor 46 to drive a reversing operation of a reversing fork 40 (wafer transfer part) is actuated, and the reversing fork 40 starts the reversing operation. Simultaneously with the actuation of the motor 46, a timer inside a control unit is cleared. It is judged by a detection signal of a photoelectric device PHSW 4 whether the reversing fork 40 is situated in a prescribed position. If this photoelectric device PHSW 4 does not detect said reversing position, said timer confirms whether a time limit has been exceeds or not. If the time limit is exceeded, it is judged that the reversing fork 40 has not been reversed for one cause or another, and an error is displayed. |
