Lift truck control system

Claim 1

A lift truck control system comprising: a clamp for clamping an object to be transported at a controllable pressure; a rotator for rotating said clamp by a controllable amount; clamp pressure sensor means, coupled to said clamp, for detecting a clamp pressure data, indicative of a pressure with which said object to be transported is clamped by said clamp; angle sensor means for detecting a rotator angle data indicative of a rotational angle of said rotator from a reference angle position; pressure memory means for storing a plurality of clamp pressure data to be set for said clamp, in a plurality of memory areas; angle memory means for storing a plurality of rotator angle data to be set for said rotator, in a plurality of memory areas; selector means for selecting one of said plurality of memory areas of said pressure memory means and one of said plurality of memory areas of said angle memory means; readout means for, in a selection mode, reading out clamp pressure data and rotator angle data from said selected memory areas of said pressure memory means and said angle memory means respectively; command generating means for generating a clamp command to said clamp, and generating turn commands which include right turn and left turn commands; and control means, responsive to said clamp command from said command generating means and coupled to said readout means, for comparing said clamp pressure data, read out by said readout means, with said detected clamp pressure data detected by said clamp pressure sensor means and adjusting a pressure of said clamp to have a clamp pressure equal to said readout clamp pressure, and responsive to said turn commands from said command generating means, for comparing said rotator angle data read out by said readout means with said detected rotator angle data detected by said angle sensor means and adjusting an angle of said rotator by commanding said rotator to rotate to an angular position equal to the readout rotator angle.