Automatic positioning system for a carriage in a storage and retrieval system

Claim 1

An automatic positioning system for a commodity carriage in an automatic storage system, comprising, shelves arranged to have commodity storage positions extending in the vertical and horizontal direction, a commodity carriage adopted to move up and down and right and left along a front face of the shelves, vertical position code marks and horizontal position code marks identifying said storage positions, said code marks arranged within the movable range of the carriage, a code scanning device included within the carriage for reading said position code marks, a control circuit responsive to an output of said code scanning devices for controlling the operation of the carriage and for stopping the carriage at a position facing a designated storage position, said position code marks identifying N storage positions in either the vertical or horizontal direction as one group of storage spaces, wherein N is a natural number larger than 1 but much less than the total number of storage positions extending in either the vertical or horizontal direction, each group of N storage spaces including a reference mark at a predetermined position within the N storage spaces, N mark scanning devices for detecting the N marks are installed on the carriage to correspond to N spaces of storing positions face to face, the detecting circuit is built into the above-mentioned first control circuit to detect which one of the N pieces of mark detective devices has output, and the feature controlling the movement of the carriage to receive output from the mark detective device corresponding to the designated storing position.