Work and feed control system for cutting machines

摘要

A control system for a cutting machine is disclosed in which the relative motion between a cutting tool, supported by a cutting motor, and the material to be cut is controlled by a feed motor. The cutting motor load level is continuously monitored and used to derive a load level signal which is related to the cutting motor load level and a desired cutting load level. The feed motor's forward speed is controlled to increase at a selected fixed rate until the cutting motor load level is substantially equal to the desired cutting load level. Whenever the cutting motor load level increases above the desired cutting load level, representing an overload condition, the speed of the feed motor in the forward direction is reduced at the rate of increase of the overload condition. If the cutting motor load level exceeds a threshold load level, the feed motor is driven in a reverse direction at a speed which increases or decreases at a rate related to the rate at which the cutting motor load level increases above or decreases toward said threshold load level.