Sony Corporation

Sanyo Electric Co., Ltd.

Koichi Inagaki

Noriaki Okada

Yuichi Nanae

A sensorless motor driving circuit including a detection circuit for detecting a reference position for the rotating rotor based on an excitation coil induction voltage, a differential pulse generating circuit for generating a differential pulse using a detection circuit output signal, a phase-locked loop circuit capable of generating a clock pulse, having a phase comparator for comparing the differential pulse with the clock pulse after the clock pulse has been frequency divided, an activation pulse generator for counting the clock pulses and generating an activation pulse when the differential pulse is not generated within the duration of a prescribed number of counts, a latch circuit for generating a delayed pulse delayed by a prescribed amount from the reference position of the rotor by counting the clock pulses or by using the activation pulse, a generating circuit for generating conduction switching signals for the excitation coils based on the delayed pulse and a driver circuit for bringing about conduction in the excitation coils based on the conduction switching signal.

Sensorless motor driving circuit having a comparative phase lock loop arrangement

An iron motor device includes an iron core motor the rotor of which is rotationally driven a pre-set angle by electromagnetic induction responsive to phase switching of current supply to two-phase coils wound on an iron core, and a driving control unit for generating a driving control signal based on the phase information of differentially phased backward voltages induced in the two-phase coils. The driving control unit causes shorting of the backward voltage induced in the coil the current supply in which is interrupted by phase switching of current supply to the two-phase coils by providing a pre-set time delay in the turn-off timing of the switching device connected to the coil the current conduction in which is interrupted. The method for drive controlling the iron core motor device is also disclosed.

Iron core motor device

A brushless sensorless motor driving circuit for driving a motor having a rotatable rotor and a plurality of excitation coils in which a motor starting mode may be smoothly switched to a normal driving mode so as to reduce a fluctuation in a starting time. The sensorless motor driving circuit includes a detection circuit for detecting a generated induction voltage from the excitation coils; a phase-locked loop circuit for generating a clock pulse; a delay pulse generating circuit for generating a delay pulse based on the clock pulse; a switching signal generating circuit for generating conduction switching signals in accordance with the delay pulse and an output signal from the detection circuit for causing an excitation pattern of the excitation coil to be switched to another excitation pattern; and starting pulse inserting circuits for inserting a starting pulse based on the clock pulse in the detection circuit when the induction voltage is not generated.

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Chiba, Japan

Koichi Inagaki