| 摘要 |
A drive shaft of an intermittently movable conveyor is alternately entrainable, via respective slipping clutches, by a high-speed and a low-speed input shaft, the switchover to low speed occuring shortly before the arresting of the drive shaft at the end of an operating cycle. A pulse counter excited by the drive shaft measures a braking interval in the final phase of each operating cycle and, at the inception of that interval, triggers a generator of progressively increasing voltage whose output causes the switchover upon reaching a reference value registered in a storage circuit. Depending upon the length of time required for the drive shaft speed to reach its lower limit, the stored reference voltage is either increased or reduced to delay or advance the switchover point to a predetermined instant slightly preceding the end of the cycle.
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