| 摘要 |
PURPOSE:To improve the accuracy of detecting abnormal rotation in an endlessly-rotated rotary rack with a tray by outputting an abnormal signal when with a tray driving motor turned on electricity, a signal proportional to the tray moving speed is not input within a fixed time. CONSTITUTION:While a tray is driven, a timer 18 is operated by a motor turn- on state detecting signal F. When the tray is moved at a normal speed, before a preset time passes, a detection signal from a photoelectric switch PHS-F is input as a reset signal G to the timer 18, and the timer is set at 0. Accordingly, an abnormal rotation detection signal M with the lapse of the preset time is not output. If the moving speed decreases, and a reset signal G is not input within the preset time, however, the timer 18 is not set at 0, so that an abnormal rotation detection signal H is output with the lapse of time, and a motor-off command is provided to stop the driving of a motor. |
