Recorder chart motor drive - synchronises motor with adjustable time control provided by electronic circuit with Miller integrator and triggered condenser

摘要

The motor drive system permits the motor to be driven accurately at a speed within a predetermined range for the drive of recorder charts in which the chart displacement by the motor is used as a time scale. A main oscillator (10) generates pulses which are fed to a power amplifier (24) which in turn drives the motor through a matching unit. The pulse frequency is controlled from a source (18, 20, 22) stabilised in frequency and voltage. The main oscillator may contain a Miller integrator (14) with a current generator (12) controlled by the control voltage to a charge a condenser as well as a trigger circuit (16) for the periodic discharge of the condenser. Speed is controlled by switching condensers of charging current.