Abstract: A three-dimensional fabrication apparatus includes a flattening member and a rotation drive unit. The flattening member moves on layers of a fabrication material to flatten an upper surface of the layers of the fabrication material. The rotation drive unit rotates the flattening member and determines a circumferential position of the flattening member.

Abstract: A permanent magnet motor is provided, which includes a rotor including a rotation axle and a plurality of magnetized rotor magnets on a periphery, which rotor magnets are magnetized to form alternately N-poles and S-poles; first and second ring-shaped-claw-pole units, whose inner circumferences face the rotor magnets, including a plurality of first and second claw-poles along the inner circumference, the first and the second claw-poles being closely adjacent to each other extending alternately in upward and downward axis directions of the rotation axle, bottom sides of the first and the second claw-poles forming a ring shape. A first opening portion is formed in a first joint surface of the first ring-shaped-claw-pole unit, to be joined to the second ring-shaped-claw-pole unit, and the second opening portion is formed in a second joint surface of the second ring-shaped-claw-pole unit, to be joined to the first ring-shaped-claw-pole unit.

Abstract: A current detecting device includes: a drive signal generating unit configured to generate a control signal based on a control voltage value indicating drive force to be applied to a target; a current detecting unit configured to detect a current value output based on the control signal generated by the drive signal generating unit; and a correction unit configured to correct the current value detected by the current detecting unit, based on at least a magnitude of the control voltage value.

Abstract: A motor controller that controls a motor in a first control method based on a first current command value and a second control method based on a second current command value. The motor controller includes an analog-to-digital converter to generate the second current command value based on a reference signal externally input to the motor controller and a current limit generator to generate an upper limit value of the first current command value based on the second current command value.

Abstract: A novel motor controller controls a stepping motor and includes a command value calculator to calculate and output a speed command value and an angle command value based on a reference clock. A control method selector is included to select one of the open-loop control and the closed-loop control in accordance with the speed command value. A command value output unit is included to output a first target value as the first current command value when the open-loop control is selected and outputs a second target value as the second current command value when the closed-loop control is selected. The motor controller controls the stepping motor based on the first target value when the open-loop control is selected and the second target value when the closed-loop control is selected.

Abstract: A motor controller that controls a motor in a first control method based on a first current command value and a second control method based on a second current command value. The motor controller includes an analog-to-digital converter to generate the second current command value based on a reference signal externally input to the motor controller and a current limit generator to generate an upper limit value of the first current command value based on the second current command value.

Abstract: A novel motor controller controls a stepping motor and includes a command value calculator to calculate and output a speed command value and an angle command value based on a reference clock. A control method selector is included to select one of the open-loop control and the closed-loop control in accordance with the speed command value. A command value output unit is included to output a first target value as the first current command value when the open-loop control is selected and outputs a second target value as the second current command value when the closed-loop control is selected. The motor controller controls the stepping motor based on the first target value when the open-loop control is selected and the second target value when the closed-loop control is selected.

Abstract: A current detecting device includes: a drive signal generating unit configured to generate a control signal based on a control voltage value indicating drive force to be applied to a target; a current detecting unit configured to detect a current value output based on the control signal generated by the drive signal generating unit; and a correction unit configured to correct the current value detected by the current detecting unit, based on at least a magnitude of the control voltage value.

Abstract: A motor driving apparatus for causing drive current to flow in first and second armature coils of two-phases to rotate a rotator, includes a drive unit configured to give first and second PWM pulse signals to ends of the first and second armature coils. The drive unit includes a first shift unit configured to, when a difference between pulse widths of the first PWM pulse signals given to the ends of the first armature coil is less than or equal to a first predetermined value, shift forward any one of pulses of the first PWM pulse signals, and a second shift unit configured to, when a difference between pulse widths of the second PWM pulse signals given to the ends of the second armature coil is less than or equal to a second predetermined value, shift backward any one of pulses of the second PWM pulse signals.

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: A motor driving apparatus for causing drive current to flow in first and second armature coils of two-phases to rotate a rotator, includes a drive unit configured to give first and second PWM pulse signals to ends of the first and second armature coils. The drive unit includes a first shift unit configured to, when a difference between pulse widths of the first PWM pulse signals given to the ends of the first armature coil is less than or equal to a first predetermined value, shift forward any one of pulses of the first PWM pulse signals, and a second shift unit configured to, when a difference between pulse widths of the second PWM pulse signals given to the ends of the second armature coil is less than or equal to a second predetermined value, shift backward any one of pulses of the second PWM pulse signals.

Abstract: A permanent magnet motor is provided, which includes a rotor including a rotation axle and a plurality of magnetized rotor magnets on a periphery, which rotor magnets are magnetized to form alternately N-poles and S-poles; first and second ring-shaped-claw-pole units, whose inner circumferences face the rotor magnets, including a plurality of first and second claw-poles along the inner circumference, the first and the second claw-poles being closely adjacent to each other extending alternately in upward and downward axis directions of the rotation axle, bottom sides of the first and the second claw-poles forming a ring shape. A first opening portion is formed in a first joint surface of the first ring-shaped-claw-pole unit, to be joined to the second ring-shaped-claw-pole unit, and the second opening portion is formed in a second joint surface of the second ring-shaped-claw-pole unit, to be joined to the first ring-shaped-claw-pole unit.

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 position estimation device for estimating a position of a rotator of a motor includes an estimation unit configured to estimate a rotational position of the rotator of the motor using a magnetic flux estimation value of the motor, which is calculated by inputting an electric voltage instruction value to be inputted to the motor and a coil electric current value detected from the motor into a motor model in which the motor is identified; and a derivation unit configured to derive a magnetic flux deviation amount due to a distortion of a magnetic flux waveform of the motor according to the estimated rotational position. The estimation unit corrects the magnetic flux estimation value based on the derived magnetic flux deviation amount, modifies the estimated rotational position based on the corrected magnetic flux estimation value, and outputs the modified rotational position.

Abstract: A motor drive control apparatus supplies drive currents including orthogonal alternating current components to armature coils of a motor so that a magnetized rotor is rotated. The motor drive control apparatus includes a high frequency generator that generates a high frequency signal which is superimposed on one of the drive currents, a position estimator that receives position information indicating an estimated position of the rotor based on a response signal to the high frequency signal, and an amplitude controller that controls amplitudes of the drive currents according to the position information.

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 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 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.