Machine-tool numerical control circuit - has X-axis and Z-axis adaptive control using an adder to vary the displacement requirement

摘要

The displacements are controlled through a digital integrator consisting of a store for the displacement, a pulse stepped adder and a sum store. The adder is enabled by pulses derived from the rotation of the machine. The output of the sum store gives the X and Z drives. The displacement store contains a value which is controlled by a cutting parameter difference signal. This comes from a comparator fed by the set-point and measured variable. The value after limiting by constants is fed to a voltage controlled oscillator the output of which, dependent on the sign of the signal is gated into the add or subtract ports of an adder. The adder controls the displacement store value. Thus when the tool is far from the required position it is moved quickly and it is slowed as the position is reached.