摘要 |
An automatic control for various domestic appliances has a ferrite core which surrounds the run winding for the drive motor of the appliance. The run winding represents the primary winding for the ferrite core, which has a secondary winding at which a brief output voltage is generated whenever the run winding current changes direction. This sensor in combination with a voltage zero detector circuit and post-connected logic circuitry generates a voltage pulse and a phase pulse which are respectively related to the voltage level of the drive motor and the motor output torque which is required to operate a movable member in the appliance. A microcomputer is utilized to generate a representative digital phase number which corresponds to the torque expended in the appliance. The phase number is utilized in various programs of the microcomputer for automatically controlling various functions of the appliance as well as other events in an operational sequence upon the attainment of selected torque levels.
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