| 摘要 |
PURPOSE:To prevent dislocation of a stopping position when a conveyed material holding means is lowered by lowering it again after the lowering is stopped once in a position higher by a prescribed height shown by the height information when the conveyed material holding means is lowered. CONSTITUTION:A raising-lowering sensor 38 detect a height of a tongue unit 4, and a motor driver 723 energizes a raising-lowering motor 35 in a direction indicated by a controller 6, and an interface 724 reads a condition of the raising- lowering sensor 38, and transfers it to the controller 6. When being lowered, it indicates reverse energization of the raising-lowering motor 35 to the motor driver 723, and starts to lower the unit 4, and indicates de-energization of the raising-lowering motor 35 when a present height of the tongue unit 4 becomes equal to or lower than a sum value of a present stacked height at a pickup point and a prescribed margin, and stands by for sufficient time to stop to lower the unit 4. Afterward, the lowering is started by energizing reversely the raising-lowering motor 35 again. Thereby, the tongue unit 4 can be stopped in a proper height correctly. |
