Operating circuit including an oscillating circuit capacitor coupled to an auxiliary winding for an apparatus that measures the unbalance of a rotary member

摘要

An operating circuit for use in an apparatus for measuring unbalance of a rotary member in which the drive for the rotary member is by means of a single-phase ac motor with a single-phase main winding and an auxiliary winding which is electrically displaced through 90 DEG . Under at least approximately load-free operating conditions, a capacitor is connected in parallel with the auxiliary winding to reduce fluctuating angular speeds of the rotor of the motor when the motor is operating in an approximately load-free condition.