Minebea Mitsumi Inc.

Minebea Company, Limited

Toshihiro Tamitsuji

Yuya Hisatomi

Hidetoshi Hijikata

Yuuya Hisatomi

Hiroyuki Kaidu

Shinichi Suzuki

Shunsuke Kamimura

Hiroaki Murakami

Yuma Ohno

Ken Yoshida

Masahiro Tanaka

Hitoshi Umeda

A motor includes a rotor having a rotation shaft, a stator arranged oppositely in a circumferential direction of the rotor, and a pair of bearing portions rotatably supporting the rotation shaft, the pair of bearing portions each include a first bearing being rotatable together with the rotation shaft and a second bearing being rotatable together with the first bearing, the first bearing rotates together with the rotation shaft when the first bearing is normal, and the second bearing as well as the first bearing rotates together with the rotation shaft when the first bearing is abnormal.

Motor, motor state detection device, and motor state determination device

A motor drive control device capable of determining a drive state of a motor is provided. The motor drive control device includes a plurality of motor drive circuits performing, based on drive control signals (Scaand Sca) for controlling the number of rotations of a motor, control of energization of the motor and outputting FG signals (fgand fg) having a cycle corresponding to the actual number of rotations of the motor, a composite signal generation circuit receiving an input of each of the FG signals output from the motor drive circuits and generating a composite signal by combining input signals, and a drive control circuit generating, based on a speed command signal indicating a target number of rotations of the motor, the drive control signals and outputting the drive control signals to each of the motor drive circuits. The FG signals output from the motor drive circuits have a phase difference from each other.

Motor drive control device, fan, and motor drive control method

The present application makes it possible to measure a PWM signal in a wide frequency range. A PWM signal measurement device () includes: a first duty cycle measurement unit () of a capture type configured to measure a frequency (f) and a duty cycle of a PWM signal (Sc); a voltage measurement unit () configured to measure a smoothed voltage (Vad) obtained by smoothing the PWM signal using a smoothing circuit (); a second duty cycle measurement unit () of a smoothing type configured to measure a duty cycle of the PWM signal on the basis of a measured voltage value (Vadm) of the smoothed voltage; and a measurement-type selecting unit () configured to select one of the capture type or the smoothing type on the basis of a measured value of the frequency and a measured value of the smoothed voltage.

PWM signal measurement device, motor drive control device, PWM signal measurement method, and motor drive control method

A motor drive control device driving a motor having a first system coil and a second system coil, the motor drive control device comprising: a first drive circuit controlling energization of the first system coil; a second drive circuit controlling energization of the second system coil; and a signal output circuit detecting a first voltage that is a voltage at a middle point of the first system coil and a second voltage that is a voltage at a middle point of the second system coil, and outputting an output signal concerning whether or not any one of the first system coil and the second system coil is in an open state, based on a detection result of the first voltage and a detection result of the second voltage.

Motor drive control device

A motor drive control device driving a motor having a first system coil and a second system coil, the motor drive control device comprising: a first drive circuit controlling energization of the first system coil; a second drive circuit controlling energization of the second system coil; a first temperature sensor detecting a temperature of the first drive circuit; a second temperature sensor detecting a temperature of the second drive circuit; and a signal output circuit outputting an output signal concerning whether or not any one of the first system coil and the second system coil is in an open state, based on a detection result by the first temperature sensor and a detection result by the second temperature sensor.

A motor drive control device causes a single phase motor including a coil of a first system and a coil of a second system to be driven. The motor drive control device has a first driving circuit configured to perform control to energize the coil of the first system, a second driving circuit configured to perform control to energize the coil of the second system, and a driving control unit configured to control an operation of the first driving circuit and an operation of the second driving circuit. The driving control unit has a driving voltage detecting unit configured to detect a driving voltage applied to the first driving circuit and a driving voltage applied to the second driving circuit, and a compensation control unit configured to cause one driving circuit between the first driving circuit and the second driving circuit to execute a maintenance operation for maintaining rotation of the single phase motor, based on a detection result of the driving voltage detecting unit.

Motor drive control device and control method for motor drive control device

A motor drive control device for driving a single phase motor having a coil of a first system and a coil of a second system includes a first drive circuit configured to control energization to the coil of the first system, a second drive circuit configured to control energization to the coil of the second system, and an adjustment circuit to which a first monitor voltage output from the first drive circuit and a second monitor voltage output from the second drive circuit are input. One or both of the first and second drive circuits has at least one of an input terminal and an output terminal. The adjustment circuit performs an adjustment operation of applying a predetermined voltage to at least one of the input terminal and the output terminal based on the first and second monitor voltages.

Motor drive control device and method of controlling motor drive control device

A motor device includes a motor, a motor driving control device and a position detector for outputting a position detection signal. The motor includes magnetic poles (n*6) and coils wound around teeth (n*4) where n is a positive integer. The coils are arranged in a peripheral direction such that the first-system coils and the second-system coils are alternately arranged. The motor driving control device includes a first drive circuit and a second drive circuit, each including an inverter circuit and a control circuit portion. The first drive circuit energizes the first-system coils and the second drive circuit energizes the second-system coils at an energization timing different from that of the first-system coils.

Motor device, motor driving control device and motor driving method

A motor drive controller includes: an advance-angle reference voltage generator that generates an advance-angle reference voltage; a back electromotive voltage comparator that generates phase signals of phases at a cross timing of the advance-angle reference voltage and back electromotive voltages of phases of a motor; and a controller that operates to perform a process including: detecting a rotation speed of the motor based on the phase signals of the phases; increasing the advance-angle reference voltage when the rotation speed moves from a high speed to a low speed; and decreasing the advance-angle reference voltage when the rotation speed moves from a low speed to a high speed.

Motor drive controller and method for controlling motor

A motor driving device comprises: an AC/DC converter that converts alternating current power into direct current power; a motor driving unit that operates based on the direct current power supplied from the AC/DC converter and outputs a driving signal to a motor; and a start-up auxiliary circuit that is arranged on a path connecting the AC/DC converter and the motor driving unit, wherein the start-up auxiliary circuit: delays an output of the driving signal for a first predetermined time period after the supply of the alternating current power from the alternating current power supply to the AC/DC converter starts; and gradually increases a driving voltage so that current flowing in a driving coil of the motor is limited to a predetermined value or smaller for a second predetermined time period after the output of the driving signal from the motor driving unit starts.

Motor driving control device

A DC-DC converter, which is configured to step down a direct current voltage and then outputs to a load, the DC-DC converter comprising: a switching device that converts the direct current voltage into an alternating current voltage; a rectification unit that rectifies the alternating current voltage; an output capacitor that is connected in parallel with the load, and a smoothing inductor comprising a plurality of divided inductors connected in series, wherein at least one of the number of windings and the number of layers of respective windings of the divided inductors of the smoothing inductor is adjusted so that a sum total of inductances of the divided inductors become a desired inductance and so that a sum total of floating capacitances of the plurality of the divided inductors is smaller than a floating capacitance of single inductor having an equivalent inductance.

DC-DC converter

An image input device includes a turn-on circuit and a converting circuit for receiving light reflected at an object and converting it into an electrical signal. The image input device is connected to a laser device as an output device. The turn-on circuit includes a triangular wave generating circuit, an error amplifier, a pulse width modulator, a lamp turn-on circuit, a xenon lamp and a protection circuit. The converting circuit includes an oscillator, a system control unit having a microprocessor to control the whole image input device, and image sensors. A same clock having a certain frequency from the oscillator is supplied to the turn-on circuit and the system control unit in the converting circuit thereby controlling the turn-on circuit to synchronize with driving signals of the image sensors.

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Iwata, Japan

Toshihiro Tamitsuji