Path control for drives of handling equipment

摘要

The invention is concerned with simplifying and reducing the price of path controls for drives of handling equipment, especially those of stacking and transfer apparatus. To this end, a shaft encoder (9, 10) is provided which has, in each case, an absolutely coded code disc (11) with preferably eight or more tracks (12, 13). The track signals are analysed in a freely programmable control circuit (14) which can operate at a clock frequency of 50 Hz or less. This is possible as a result of combined incremental and absolute analysis of the track signals. Until certain predetermined braking points on the track curve are reached, the track signals are counted incrementally. As the speed of the disc decreases, more and more tracks can be analysed, until ultimately, at creep speed, absolute analysis takes place over all tracks for absolute path measurement. For the drive control, it is recommended that the control circuit (14) be connected via a frequency converter (15) to three-phase motors (7, 8). <IMAGE>