Process control apparatus

Abstract

The invention relates to process control in general and to numerical control machining in particular. A programmable digital controller is associated with a digital motion control unit in which are stored numerical data for point-to-point operation of a machine tool, for instance a grinder. The motion control unit is of the incremental type and generates command pulses which are applied to a stepping motor. Numerical data are stored defining desired displacement, velocity and sign of travel, and dress compensation. A feedback loop with the machine tool provides corrective pulses when the command pulses sent are not in exact relation with the increments of displacement effectively imparted on the tool. The programmable controller can be coupled to a plurality of motion control unit controlling one or more machine tools, or axes, and it is performing sequence control in relation to industrial process as well.

Dependencies are inferred from the claim text.