Method and control circuit for controlling phase splitting start single-phase induction motor
AssigneeTsubaki Emerson Co.
InventorsTsuneo Nagahama, Yoshiaki Yokoi
Life of this patent
Estimating the term…
Abstract
After a power source is turned on, the motor stars by feeding a current to the auxiliary wiring for a first predetermined period. Then, a voltage induced in the auxiliary wiring is detected. Whether or not the detected inducted voltage is lower than a predetermined voltage is judged. The detected induced voltage is judged to be lower than the predetermined voltage when the shredder cannot cut the paper and the rotation speed of the motor is decreased. In this case, since the current is fed to the auxiliary wiring for a second predetermined period, the rotation speed of the motor is increased and an output torque is also increased, which leads to the cuttable state.
Claims6
A method for controlling a drive of a phase splitting start single-phase induction motor having an auxiliary wiring for starting, comprising the steps of:
- feeding a current to said auxiliary wiring for a first predetermined period, after a power source is turned on;
- interrupting the current fed to said auxiliary wiring and detecting a voltage induced in said auxiliary wiring, after an elapse of said first predetermined period;
- judging whether or not the detected induced voltage is lower than a predetermined voltage;
- and
- feeding the current to said auxiliary wiring for a second predetermined period, each time said induced voltage is judged to be lower than the predetermined voltage.
A control circuit for driving and controlling a phase splitting start single-phase induction motor having an auxiliary wiring for starting, comprising:
- current feeding means for feeding a current to said auxiliary wiring;
- interrupting means for interrupting the current fed to said auxiliary wiring and detecting means for detecting a voltage induced in said auxiliary wiring;
- judging means for judging whether the induced voltage detected by said detecting means is lower than a predetermined voltage;
- and
- controlling means for controlling said current feeding means, interrupting means, detecting means and judging means so that after a power source is turned on, said motor is started by once feeding the current to said auxiliary wiring for a first predetermined period, interrupting the current fed to said auxiliary wiring and detecting the voltage induced in said auxiliary wiring after the current is fed for the first predetermined period, and each time the induced voltage detected by said detecting means is judged to be lower than the predetermined voltage by said judging means, the current is fed to said auxiliary wiring for a second predetermined period.
Dependencies are inferred from the claim text.