Abstract: A motor controller receiving as input an encoder signal changing in response to a driving position of a motor, outputting a motor driving command in response to the encoder signal to control at least one of the driving position or a driving velocity of the motor, includes an interrupt processing section to execute interrupt operations every prescribed interrupt cycle, a low-frequency processing section to selectively execute a subset of the interrupt operations every prescribed number of the interrupt cycles, and a high-frequency processing section to execute another subset of the interrupt operations every prescribed interrupt cycle, wherein the high-frequency processing section executes at least an operation to detect the driving position indicated by the encoder signal, wherein the low-frequency processing section executes at least an operation to generate the motor driving command.

Abstract: A motor control device controls a speed of a motor. The motor control device includes: a target speed generating unit that generates a target speed; a speed detecting unit that detects a current speed of the motor; a speed comparing unit that compares the target speed with the current speed to calculate a speed error; an error amplifying unit that amplifies the speed error and outputs a control value; and a motor driving unit that drives the motor in accordance with the control value. The error amplifying unit has proportional integral characteristics by which the speed error is amplified with a proportional gain and integration is performed in a lower frequency range than an integral corner frequency, increases the proportional gain as the current speed is higher, and shifts the integral corner frequency to a lower frequency as the current speed is higher.

Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.

Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.

Abstract: Disclosed is an angle detection device including plural sensors that output corresponding sinusoidal signals, wherein each of the sinusoidal signals varies sinusoidally depending on a rotational angle of a rotor of a motor, and each of the sinusoidal signals has a phase that depends on a position of the corresponding sensor; a vector generating unit that generates a vector represented by a result of mutually operating at least two of the sinusoidal signals; a vector rotation unit that rotates the vector by operating the vector and reference sine waves having corresponding phases; and an angle search unit that causes the vector rotation unit to sequentially rotate the vector until a phase of the vector becomes a predetermined phase, and that detects an angle between the vector prior to being rotated and the predetermined phase as the rotational angle of the rotor of the motor.

Abstract: A motor control apparatus includes: a driving control unit that performs driving control of a motor in accordance with a drive command; an interrupt control unit that starts and executes interrupt processing for performing the driving control at an interrupt cycle; a first processing unit that executes same first processing every time the interrupt processing starts; and a second processing unit that selects and executes a different piece of processing from second processing every time the interrupt processing starts. The interrupt control unit executes at least one piece of the first processing before executing the second processing in the interrupt processing.

Abstract: A motor controller receiving as input an encoder signal changing in response to a driving position of a motor, outputting a motor driving command in response to the encoder signal to control at least one of the driving position or a driving velocity of the motor, includes an interrupt processing section to execute interrupt operations every prescribed interrupt cycle, a low-frequency processing section to selectively execute a subset of the interrupt operations every prescribed number of the interrupt cycles, and a high-frequency processing section to execute another subset of the interrupt operations every prescribed interrupt cycle, wherein the high-frequency processing section executes at least an operation to detect the driving position indicated by the encoder signal, wherein the low-frequency processing section executes at least an operation to generate the motor driving command.

Abstract: An image forming apparatus includes an optical scanning unit, a measurement unit, a first adjustment unit and a second adjustment unit. The optical scanning unit includes a plurality of light sources to emit laser beams, a single oscillating mirror deflector to deflect the laser beams used for scan processing in a main scanning direction, and a scan-focusing member to focus the deflected laser beams onto a plurality of photoconductors. The measurement unit measures a resonance frequency of the oscillating mirror deflector. The first adjustment unit adjusts a speed of the photoconductors in a sub-scanning direction. The second adjustment unit adjusts a magnification ratio of image data in the sub-scanning direction. The first adjustment unit and the second adjustment unit adjust the image magnification ratio of image data in the sub-scanning direction depending on the resonance frequency as measured by the measurement unit.

Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.

Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.

Abstract: Disclosed is an angle detection device including plural sensors that output corresponding sinusoidal signals, wherein each of the sinusoidal signals varies sinusoidally depending on a rotational angle of a rotor of a motor, and each of the sinusoidal signals has a phase that depends on a position of the corresponding sensor; a vector generating unit that generates a vector represented by a result of mutually operating at least two of the sinusoidal signals; a vector rotation unit that rotates the vector by operating the vector and reference sine waves having corresponding phases; and an angle search unit that causes the vector rotation unit to sequentially rotate the vector until a phase of the vector becomes a predetermined phase, and that detects an angle between the vector prior to being rotated and the predetermined phase as the rotational angle of the rotor of the motor.

Abstract: A motor driving device driving coil terminals of a three-phase motor to flow three-phase currents includes: a pulse modulator generating three-phase modulation pulses, each of which has a duty ratio in accordance with a voltage level of a coil terminal; a shift amount selection unit selecting a first shift amount corresponding to at least one of two predetermined amounts according to a pulse width of the longest pulse among the three-phase modulation pulses; a first shift unit shifting the second-longest pulse among the three-phase modulation pulses backward by the first shift amount to delay timing; a second shift unit shifting the third-longest pulse among the three-phase modulation pulses backward by a predetermined second shift amount to delay timing; and an inverter driving each of the coil terminals by switching a driving power supply with the three-phase modulation pulses by reflecting shift results of the first and second shift units.

Abstract: A motor speed controller controls a motor speed to generate a phase reference pulse; generates a FG pulse per rotary angle of the motor; detects a difference between the number of phase reference pulses and the number of FG pulses for output as an integer number phase difference; detects and measures a time difference between an edge of the phase-reference pulse and an edge of the FG pulse in units of the reference clock for output as a decimal fraction phase difference; adds the integer number phase difference to the decimal fraction phase difference at a predetermined ratio for output as a phase difference; and controls driving of the motor in accordance with the phase difference.

Abstract: A motor driving device driving coil terminals of a three-phase motor to flow three-phase currents includes: a pulse modulator generating three-phase modulation pulses, each of which has a duty ratio in accordance with a voltage level of a coil terminal; a shift amount selection unit selecting a first shift amount corresponding to at least one of two predetermined amounts according to a pulse width of the longest pulse among the three-phase modulation pulses; a first shift unit shifting the second-longest pulse among the three-phase modulation pulses backward by the first shift amount to delay timing; a second shift unit shifting the third-longest pulse among the three-phase modulation pulses backward by a predetermined second shift amount to delay timing; and an inverter driving each of the coil terminals by switching a driving power supply with the three-phase modulation pulses by reflecting shift results of the first and second shift units.

Abstract: An optical scanner is disclosed that has an optical source unit that emits a laser beam; a vibration mirror by which the laser beam from the optical source unit is deflected to scan; a driving circuit that vibrates the vibration mirror based on a driving signal generated from a reference clock; a light-receiving element that receives the laser beam within the scanning area of the laser beam; and a controlling unit that corrects the driving signal so as to make a phase deviation between the reference phase clock and the output signal of the light-receiving element constant.

Abstract: An image forming apparatus includes an optical scanning unit, a measurement unit, a first adjustment unit and a second adjustment unit. The optical scanning unit includes a plurality of light sources to emit laser beams, a single oscillating mirror deflector to deflect the laser beams used for scan processing in a main scanning direction, and a scan-focusing member to focus the deflected laser beams onto a plurality of photoconductors. The measurement unit measures a resonance frequency of the oscillating mirror deflector. The first adjustment unit adjusts a speed of the photoconductors in a sub-scanning direction. The second adjustment unit adjusts a magnification ratio of image data in the sub-scanning direction. The first adjustment unit and the second adjustment unit adjust the image magnification ratio of image data in the sub-scanning direction depending on the resonance frequency as measured by the measurement unit.

Abstract: A recording condition setting method includes the steps of: a) obtaining identification information from an information recording medium; b) searching through a table including history information indicative of temperature information detected in the vicinity of a light source and corresponding optimum recording power; c) extracting history information corresponding to the identification information; d) detecting temperature information detected in the vicinity of the light source; e) acquiring an optimum recording power by referring to the temperature information detected in step d) and the history information extracted in step c); and f) setting the optimum recording power acquired in step e) as a recording condition.

Abstract: An information recording device includes a buffer memory, a buffer management unit and a phase adjusting unit. The buffer memory temporarily stores data to be written in a recording medium. The buffer management unit starts writing the data in the recording medium if a size of the data stored in the buffer memory exceeds a first predetermined size, and suspends writing the data in the recording medium if the size of the data stored in the buffer memory becomes less than a second predetermined size. Additionally, the phase adjusting unit starts adjusting a phase error between a signal synchronous to the data and a signal synchronous to a location on the recording medium when the buffer management unit starts writing the data in the recording medium, and finishes adjusting the phase error so that the phase error becomes substantially zero before the buffer management unit suspends writing the data in the recording medium.

Abstract: An optical disk device records data on a recordable or rewritable optical disk. The optical disk device comprises zone storing means for preliminarily storing locations of a plurality of zones set by dividing a recordable or rewritable area of the optical disk from an inner periphery thereof to an outer periphery thereof, position detecting means for detecting a position on the optical disk so as to record data at the position, judging means for judging which of the zones the position corresponds to by referring to the zone storing means, and controlling means for controlling the device to perform a data-recording by a CLV method to each of the zones specified by the judging means by setting a recording velocity and a recording power for each of the zones so as to enable the data-recording to provide an equal recording density to all of the zones.

Abstract: An optical scanner is disclosed that has an optical source unit that emits a laser beam; a vibration mirror by which the laser beam from the optical source unit is deflected to scan; a driving circuit that vibrates the vibration mirror based on a driving signal generated from a reference clock; a light-receiving element that receives the laser beam within the scanning area of the laser beam; and a controlling unit that corrects the driving signal so as to make a phase deviation between the reference phase clock and the output signal of the light-receiving element constant.