Accurate control of relative speed and cut in a continuous process line
E. G. Anger, D. L. Pettit · Transactions of the American Institute of Electrical Engineers Part II Applications and Industry · 1955
Magnetic amplifier controls one d-c generator to drive a group of d-c motors to process wallboard and plasterboard. Co-ordination of belt speeds to a small fraction of 1 per-cent uses differential control synchro. Rotating knife synchronism is held by synchro-metering device.