Abstract: A motor according to the present disclosure includes a stator that includes a stator core around which a stator winding is wound; a rotating body that holds a plurality of magnets in a circumferential direction facing the stator or holds a plurality of magnets in a spoke shape from a center; a rotor that includes the rotating body, and a shaft fastened to the rotating body such that the shaft penetrates a center of the rotating body; two bearings that support the rotating body; a first metal bracket that fixes one bearing of the two bearings; and a second metal bracket that fixes the other bearing of the two bearings, and a capacitive member that has a capacitance Csb1sb2 and is located between the first metal bracket and the second metal bracket.

Abstract: A motor includes a stator that includes a stator core around which a stator winding is wound; magnets; a rotating body; a shaft; a rotor; a first bearing; a second bearing; a first metal bracket that fixes the first bearing; and a second metal bracket that fixes the second bearing. The stator core, the first metal bracket, and the second metal bracket are electrically connected, and when a connection point between the stator core and the first metal bracket or the second metal bracket is defined as a connection point A of a bearing outer ring, a capacitive member having a capacitance Cn is located between a portion having the same potential as the connection point A and a portion having a zero reference potential of a drive circuit that applies a voltage to the stator core.

Abstract: A motor includes a stator that includes a stator core around which a stator winding is wound; magnets; a rotating body; a shaft; a rotor; a first bearing; a second bearing; a first metal bracket that fixes the first bearing; and a second metal bracket that fixes the second bearing. The stator core, the first metal bracket, and the second metal bracket are electrically connected, and when a connection point between the stator core and the first metal bracket or the second metal bracket is defined as a connection point A of a bearing outer ring, a capacitive member having a capacitance Cn is located between a portion having the same potential as the connection point A and a portion having a zero reference potential of a drive circuit that applies a voltage to the stator core.

Abstract: A motor according to the present disclosure includes a stator that includes a stator core around which a stator winding is wound; a rotating body that holds a plurality of magnets in a circumferential direction facing the stator or holds a plurality of magnets in a spoke shape from a center; a rotor that includes the rotating body, and a shaft fastened to the rotating body such that the shaft penetrates a center of the rotating body; two bearings that support the rotating body; a first metal bracket that fixes one bearing of the two bearings; and a second metal bracket that fixes the other bearing of the two bearings, and a capacitive member that has a capacitance Csb1sb2 and is located between the first metal bracket and the second metal bracket.

Abstract: Electric motor includes stator, rotor, a pair of bearings, outer-ring conducting part, and printed circuit board. Outer-ring conducting part electrically couples outer rings to each other that are included respectively in the pair of bearings. Printed circuit board includes drive circuit and an impedance element. Drive circuit includes ground line. Drive circuit controls an electric current that flows through stator winding. The impedance element is formed with at least not smaller than one pair of conductive patterns. One of the conductive patterns forming the impedance element is electrically coupled with outer-ring conducting part. The other of the conductive patterns forming the impedance element is electrically coupled with ground line included in drive circuit.

Abstract: Electric motor includes stator, rotor, a pair of bearings, outer-ring conducting part, and printed circuit board. Outer-ring conducting part electrically couples outer rings to each other that are included respectively in the pair of bearings. Printed circuit board includes drive circuit and an impedance element. Drive circuit includes ground line. Drive circuit controls an electric current that flows through stator winding. The impedance element is formed with at least not smaller than one pair of conductive patterns. One of the conductive patterns forming the impedance element is electrically coupled with outer-ring conducting part. The other of the conductive patterns forming the impedance element is electrically coupled with ground line included in drive circuit.

Abstract: A motor includes a stator having a stator iron core wound with stator windings, a rotor rotatably mounted on a shaft, a bearing for supporting the shaft, and a conductive bracket for fixing the bearing. The rotor is formed of a rotary body that holds a permanent magnet and the shaft that extends through the rotary body at center and joined to the rotary body. An electrostatic capacity between the shaft and an outermost wall of the rotary body is set smaller than an electrostatic capacity between an inner ring and an outer ring of the bearing during rotation of the bearing.

Abstract: A motor of the invention has a rotary body of a rotor, and the rotary body includes an outer core constituting an outer portion of the rotary body, an inner core constituting an inner portion connected to a shaft, and a dielectric layer disposed between the outer core and the inner core. The outer core has a protruding portion that protrudes inward from an inner surface thereof, and the inner core has a protruding portion that protrudes outward from an outer surface thereof, wherein the outer core and the inner core are so disposed that an end face of the protruding portion of the outer core and an end face of the protruding portion of the inner core confront partially with respect to each other.

Abstract: A motor of the invention has a rotary body of a rotor, and the rotary body includes an outer core constituting an outer portion of the rotary body, an inner core constituting an inner portion connected to a shaft, and a dielectric layer disposed between the outer core and the inner core. The outer core has a protruding portion that protrudes inward from an inner surface thereof, and the inner core has a protruding portion that protrudes outward from an outer surface thereof, wherein the outer core and the inner core are so disposed that an end face of the protruding portion of the outer core and an end face of the protruding portion of the inner core confront partially with respect to each other.

Abstract: An electric motor includes a stator that has a stator winding wound on a stator iron core; a rotor having a rotating body with a rotating shaft in the center; a bearing for journaling the rotating shaft; and two conductive brackets for fixing the bearing. The rotating body holds a magnet such that the magnet faces the stator, and is fastened to the rotating shaft penetrating through the center of the rotating body. In the rotating body, a dielectric layer is formed between the rotating shaft and the outer circumference of the rotating body. The dielectric layer has a polygonal shape with the rotating shaft in the center. An electric device includes the thus configured electric motor.

Abstract: An electric motor includes a stator that has a stator winding wound on a stator iron core; a rotor having a rotating body with a rotating shaft in the center; a bearing for journaling the rotating shaft; and two conductive brackets for fixing the bearing. The rotating body holds a magnet such that the magnet faces the stator, and is fastened to the rotating shaft penetrating through the center of the rotating body. In the rotating body, a dielectric layer is formed between the rotating shaft and the outer circumference of the rotating body. The dielectric layer has a polygonal shape with the rotating shaft in the center. An electric device includes the thus configured electric motor.

Abstract: A rolling bearing for an inverter-driven motor has the thickness of an oil film in a steady operation condition stably maintained in a specific range, by which the withstand voltage can be controlled, and the discharge due to the shaft voltage of the inverter-driven motor is prevented and electrolytic corrosion can be suppressed. The rolling bearing for an inverter-driven motor has an inner ring, an outer ring, a rolling element, and grease, wherein a root mean square roughness of a raceway surface of at least one of the inner ring and the outer ring is 4 to 16 nm, and an oil film parameter ? in steady operation is at least 17.5.

Abstract: A motor includes a stator having a stator iron core wound with stator windings, a rotor rotatably mounted on a shaft, a bearing for supporting the shaft, and a conductive bracket for fixing the bearing. The rotor is formed of a rotary body that holds a permanent magnet and the shaft that extends through the rotary body at center and joined to the rotary body. An electrostatic capacity between the shaft and an outermost wall of the rotary body is set smaller than an electrostatic capacity between an inner ring and an outer ring of the bearing during rotation of the bearing.

Abstract: A PWM converter includes a power source current detector (9), current instruction generator (7), current controller (6) and a main circuit power control section (8), and the current controller is constituted of comparators (17, 18, 19) which compare the line current measurement results with the line current instruction values, and a logic circuit (10) which generates switching instruction signals (PU, PV, PW) based on the comparison results with use of timing signals so that the switching power devices (Q1-Q6) are selectively turned ON and OFF in the direction of reducing the difference between the line current measurement results and the line current instruction values, and thus essentially solves the prior art problems associated with gain adjustment of current error amplifiers, which is completely adjustment-free and yet inexpensive.

Abstract: A motor control apparatus supplies a current to the motor according to the control either by an average current controller or by an instantaneous current controller. The selection of the controller is done by a switching command signal selector, which selects the average current controller when the position deviation is within a specified range, and selects the instantaneous current controller when the position deviation is outside this specified range.

Abstract: In a current command type PWM inverter apparatus including first to sixth main circuit switching power devices for supplying line currents to a three-phase motor, at a periodical state updating first timing, and at least one second timing when any one of first, second and third comparison signals between respective detected line currents and respective line current command signals change after the state updating first timing, a logic circuit generates and outputs first to sixth switching command signals to the main circuit switching power devices so as to minimize errors between respective line current command signals and respective detected line currents.

Abstract: A low-cost, completely adjustment-free current-controlled PWM inverter substantially solving the conventional problems associated with the gain adjustment of a current error amplifier is provided. The current-controlled PWM inverter comprises a motor current detector, a main circuit power controller, a current comparator, a timing signal generator, and a switching control signal generator configured such that the switching control signal generator sets the switching control signal to switch the main circuit switching power elements on or off at the refresh timing and at the timing at which the current comparison result state changes.

Abstract: In a current command type PWM inverter apparatus including first to sixth main circuit switching power devices for supplying line currents to a three-phase motor, at a periodical state updating first timing, and at least one second timing when any one of first, second and third comparison signals between respective detected line currents and respective line current command signals change after the state updating first timing, a logic circuit generates and outputs first to sixth switching command signals to the main circuit switching power devices so as to minimize errors between respective line current command signals and respective detected line currents.