METHOD AND APPARATUS FOR CONTROLLING THE SHUTTLE OF A STORAGE AND RETRIEVAL MACHINE

摘要

A shuttle control for a storage and retrieval machine has a supervisory control means mounted on the base of the storage and retrieval machine and shuttle control means mounted on the carriage of the storage and retrieval machine. The supervisory control means receives shuttle operating commands and information signals and provides operating instruction signals for the shuttle to the shuttle control means. The shuttle control means receives the operating instruction signals from the supervisory control means, produces operating information signals to the supervisory control means, and controls the operation of a shuttle motor drive. Circuit means having sliding contactors moving with the carriage on vertical slide bars mounted on the mast transmit operating instruction signals and information signals between the supervisory control means and the shuttle control means at a maximum transmission rate limited by the problems of transmitting the signals through the sliding contact means. Sensing means mounted on the carriage of the storage and retrieval machine produce shuttle operating condition indicating signals to the shuttle control means at a transmission rate faster that the maximum transmission rate of the circuit means. The indicating signals are used by the shuttle control means to control the operation of the shuttle motor.