Stacker crane control system - has upper and lower photoelectric sensors side by side in vertical position on lift side

摘要

A level detector device (3,4) is provided and a lifting platform is located on an upper or a lower level in a fork zone, in which the fork can move in the extended state. A drive extent detector (9,10) detects a drive extent for a linear lifting part. A memory device (11) stores a drive extent value in a predetermined position, and a control unit (8) controls the operation of the linear lifting part on the basis of the stored value. The value stored in the memory (11) is updated when the lifting platform moves vertically between the upper and lower levels of the fork zone. The extent of the fork zone is equal to the length of a plate in a vertical direction, which is provided on a mast along which the lifting platform moves. The level detector (3,4) has an upper and a lower photo-electric sensor for detection of the plate. USE/ADVANTAGE - The stacker crane control permits a precise determn. of a stopping position.