The electric-powered actuator includes a control device including: a motor angle estimation unit, and a reverse-input holding control section having a function of engaging an engaging part with an engaged part by controlling a solenoid to set the reverse-input holding mechanism into a reverse-input holding state while the electric-powered actuator is applying a load and a function of, from the reverse-input holding state, disengaging the engaging part from the engaged part to set the reverse-input holding mechanism into a reverse-input holding release state. The reverse-input holding control section includes an engagement intermediate control function section configured to control the estimated rotation angle such that the engaged part and the engaging part come into a predetermined positional relation within a certain period of time, when the engaging part is brought into engagement with the engaged part and when the engaging part is brought out of engagement with the engaged part.

An electric actuator includes a casing having a base, on which an electric motor is fixed having a stator with radially extending straight teeth and having a plurality of coils and a rotor formed by a plurality of magnets. The coils extend in a plane parallel to the base of the casing and the rotor is extended by a pinion forming a worm gear with an axis perpendicular to the orientation of the coils. The worm gear meshes with a threaded rod extending parallel to the base of the casing, wherein the threaded rod is guided at the rear by a fixed smooth bearing or by a fixed nut, with the smooth bearing or nut being rigidly connected to a cover of the casing. The axial end of the worm gear is guided by the cover and a printed circuit, to which the plurality of coils is connected, is positioned between the stator and the threaded rod.

An image forming apparatus includes a stacking unit, a pickup roller, a motor having a winding, a rotor, and a phase, an image forming unit, an operation unit, and a receiving unit. The motor drives the pickup roller to feed a recording medium stacked on the stacking unit. The image forming unit forms an image on the fed medium. A user operates the operation unit to set an image forming condition. When, in a state where the winding is not excited, the operation unit is operated before the receiving unit receives an instruction to start forming the image, an initial operation is executed in a rotor stop state that supplies current to the winding and determines the motor phase based on the current flowing through the winding. When the instruction is received after the initial operation, the winding receives current such that the rotor rotates based on the determined phase.

A vehicle door checker integrated with a power drive unit for an automobile door includes a direct current permanent magnet electric motor subject to cogging torque. The electric motor includes a central shaft. The vehicle door checker also includes a cogging torque increase device that is mounted to the central shaft externally of the motor. The cogging torque increase device includes pairs of oppositely magnetized permanent magnets that are mounted coaxially in a stator and rotor respectively about the motor shaft. The stator magnets and the rotor magnets shift into and out of alignment with each other as the shaft is rotated such that the motor is held in multiple discrete stable positions that correspond to check positions of an automobile door.

A control method of an electrical braking system for aircraft includes a plurality of electromechanical actuators capable of applying a braking force on friction members. Each electromechanical actuator includes an electric motor equipped with one or more windings. The braking system further includes at least one power module configured to send to each electric motor winding a phase current and at least one control module configured to control, in response to a braking setpoint, the sending by the power module of a setpoint phase current determined depending on the braking force to be applied. The method further includes the variation of the phase current transmitted to each winding of the electric motor so as to cause the phase current to oscillate around the setpoint phase current.

A motor control device controls a drive of a motor in a motor drive system including the motor and a detent mechanism. The detent mechanism has a detent member that rotates integrally with an output shaft to which the rotation of the motor is transmitted, and an engaging member that moves a valley portion by a rotation of the motor and positions the output shaft by stopping within a positioning range. The motor control device includes a positioning determination unit and an energization control unit. The positioning determination unit determines whether or not the engaging member is stopped within the positioning range based on control parameter other than a detection value of a motor rotation angle sensor that detects a motor rotation angle. When the energization control unit determines that the engaging member is stopped within the positioning range, the energization control unit turns off the energization of the motor.

An image forming apparatus includes a stacking portion, a pickup roller, a motor, an image forming unit, and a controller. Upon receiving an instruction for starting a first image forming job, the controller performs an initial operation of supplying current to a motor winding of the motor in a stop state and determining a phase of the rotor based on the flowing current. Based on the determined phase, the controller supplies current to rotate the rotor from its stop state and holds the rotor at a first phase when the first job ends. Upon receiving start instructions for a second image forming job within a period until a predetermined time elapses from when the rotor is held at the first phase, the controller rotates the rotor without performing the initial operation. The controller stops supplying current to the winding if no instructions are not received for starting the second job.

An image forming apparatus includes a stacking unit, a pickup roller, a motor having a winding, a rotor, and a phase, an image forming unit, an operation unit, and a receiving unit. The motor drives the pickup roller to feed a recording medium stacked on the stacking unit. The image forming unit forms an image on the fed medium. A user operates the operation unit to set an image forming condition. When, in a state where the winding is not excited, the operation unit is operated before the receiving unit receives an instruction to start forming the image, an initial operation is executed in a rotor stop state that supplies current to the winding and determines the motor phase based on the current flowing through the winding. When the instruction is received after the initial operation, the winding receives current such that the rotor rotates based on the determined phase.

A system includes a converter operatively connected to an alternating current (AC) power source and a direct current (DC) bus, an inverter operatively connected to a motor and the DC bus, and a controller. The converter includes a first plurality of switching devices in selective communication with each phase of the AC power source and the DC bus. The inverter includes a second plurality of switching devices in selective communication with each phase of a plurality of phases of the motor and the DC bus. The controller is operable to command dropping of a brake through a passive delay circuit responsive to detection of an emergency stop condition for a load driven by the motor and reduce a voltage on the DC bus by dropping at least one phase of the AC power source and/or using a dynamic braking resistor prior to the brake physically dropping.

For controlling an electric motor to maintain a current motor position, a motor controller determines the current motor position of the electric motor and selects (S41) from a set of stable positions, defined by cogging torque of the electric motor, a selected stable position closest to the current motor position. The controller controls the motor torque of the electric motor to maintain the motor position (S4) within a defined range around the selected stable position.