Abstract: A linear motor includes a stator including a plurality of salient poles arranged at regular intervals in the Y-axis direction, and a mover movable in the Y-axis direction and facing the stator in the X-axis direction, in which the mover includes a plurality of teeth arranged in the Y-axis direction, three-phase alternate current windings wound around the teeth, a mover magnetic yoke that connects the plurality of teeth, permanent magnets each disposed in a gap between the teeth of identical phase, and magnetic flux barriers each embedded near the base of each tooth of the plurality of teeth, disposed completely within a width of each tooth in the X-axis direction, and spaced apart from the permanent magnet in the X-axis direction.

Abstract: A linear motor includes a stator having a plurality of salient poles, and a slider configured to move along a direction of extension of the stator. A U-phase coil core of the slider includes a yoke, a plurality of teeth, permanent magnets provided in respective magnet-receiving cavities located between the teeth, coil-receiving cavities formed on outer sides of the teeth set, and a U-phase coil wound in the coil-receiving cavities. The plurality of teeth project radially from the yoke toward the stator, and the width of each of the teeth as measured at the yoke side is narrower than its width as measured at the stator side.

Abstract: A linear motor includes a stator including a plurality of salient poles arranged at regular intervals in the Y-axis direction, and a mover movable in the Y-axis direction and facing the stator in the X-axis direction, in which the mover includes a plurality of teeth arranged in the Y-axis direction, three-phase alternate current windings wound around the teeth, a mover magnetic yoke that connects the plurality of teeth, permanent magnets each disposed in a gap between the teeth of identical phase, and magnetic flux barriers each embedded near the base of each tooth of the plurality of teeth, disposed completely within a width of each tooth in the X-axis direction, and spaced apart from the permanent magnet in the X-axis direction.

Abstract: A rotor of a synchronous motor includes a rotor core that includes magnet insertion holes and a plurality of slits formed on an outer peripheral side of the magnet insertion holes, and permanent magnets embedded in the magnet insertion holes. Magnetic-path forming slits are formed at intervals in a direction along a side of the permanent magnet. Magnetic paths are formed between the magnetic-path forming slits and at portions on the outside of the magnetic-path forming slits on the outermost side. An adjusting slit is formed between a predetermined magnetic-path forming slit and the permanent magnet such that a difference between quantities of magnetic flux passing through the magnetic paths adjacent to each other for widths in a direction intersecting an orientation of a magnetic pole of the permanent magnet is small.

Abstract: A rotor of a synchronous motor has a rotor core and a permanent magnet. The rotor core has a plurality of magnet insertion apertures and a plurality of slits. The permanent magnet is disposed in each of the magnet insertion apertures such that the magnetic poles of the permanent magnets are directed in a diameter direction. The slits are formed on an radially outer side of the magnet insertion aperture so as to align with intervals along a side of the permanent magnet. Magnetic paths are defined between adjacent slits. A gap that is a slot open in the axial direction of the rotor core is formed on the opposite side from a plurality of magnetic paths across the permanent magnet to adjust the magnetic resistance of the magnetic paths for making a change in magnetic flux between adjacent magnetic paths small.

Abstract: A rotor of a synchronous motor includes a rotor core that includes magnet insertion holes and a plurality of slits formed on an outer peripheral side of the magnet insertion holes, and permanent magnets embedded in the magnet insertion holes. Magnetic-path forming slits are formed at intervals in a direction along a side of the permanent magnet. Magnetic paths are formed between the magnetic-path forming slits and at portions on the outside of the magnetic-path forming slits on the outermost side. An adjusting slit is formed between a predetermined magnetic-path forming slit and the permanent magnet such that a difference between quantities of magnetic flux passing through the magnetic paths adjacent to each other for widths in a direction intersecting an orientation of a magnetic pole of the permanent magnet is small.

Abstract: A method for determining a cogging torque may include applying a substantially constant rotation torque to an output shaft of a motor without electrically energizing the motor; detecting, an angle of rotation of the output shaft of the motor at each of a plurality of angles of rotation; calculating an angular acceleration of the motor at each of the plurality of angles of rotation by second order differentiating the angle of rotation; calculating a measured torque value at each of the plurality of angles of rotation by multiplying the angular acceleration by a moment of inertia of a rotor in the motor; obtaining a measured torque waveform of the measured torque value at each of the plurality of angles of rotation as a function of the plurality of angles of rotation; and calculating a cogging torque waveform based on a frequency of the measured torque waveform.

Abstract: A rotor of a synchronous motor has a rotor core and a permanent magnet. The rotor core has a plurality of magnet insertion apertures and a plurality of slits. The permanent magnet is disposed in each of the magnet insertion apertures such that the magnetic poles of the permanent magnets are directed in a diameter direction. The slits are formed on an radially outer side of the magnet insertion aperture so as to align with intervals along a side of the permanent magnet. Magnetic paths are defined between adjacent slits. A gap that is a slot open in the axial direction of the rotor core is formed on the opposite side from a plurality of magnetic paths across the permanent magnet to adjust the magnetic resistance of the magnetic paths for making a change in magnetic flux between adjacent magnetic paths small.

Abstract: A plurality of coils C1 to Cm that constitutes a whole winding L of each phase is divided into g coil groups G1 to Gg for each phase. Each coil group is, for example, constituted by coils C1 to C4 wound around four polar teeth continuously disposed. The number of turns of respective end coils C1 to C4 of the coil group is less than the number of turns of central coils C2 and C3. Further, the whole winding L includes n partial windings N1 to Nn, in which a coil Cj (j is an integer in the range from 1 to m) is constituted by n sub coils S(1,j) to S(n,j) that are formed by the n partial windings. It is feasible to set a non-integer value as an effective number of turns of a coil when the number of turns of each sub coil is appropriately selected.

Abstract: There is provided a cogging torque measuring apparatus including a drive mechanism for rotatively driving an output shaft of a motor without energizing the motor, a rotation angle detector for detecting an angle of rotation of the motor, an angular acceleration calculating unit for calculating an angular acceleration from the angle of rotation, a torque calculating unit for converting the angular acceleration into a torque, and a signal processing unit for calculating, based on the angle of rotation detected by the rotation angle detector and the torque calculated in the torque calculating unit, a waveform of a cogging torque for the angle of rotation.

Abstract: A plurality of coils C1 to Cm that constitutes a whole winding L of each phase is divided into g coil groups G1 to Gg for each phase. Each coil group is, for example, constituted by coils C1 to C4 wound around four polar teeth continuously disposed. The number of turns of respective end coils C1 to C4 of the coil group is less than the number of turns of central coils C2 and C3. Further, the whole winding L includes n partial windings N1 to Nn, in which a coil Cj (j is an integer in the range from 1 to m) is constituted by n sub coils S(1,j) to S(n,j) that are formed by the n partial windings. It is feasible to set a non-integer value as an effective number of turns of a coil when the number of turns of each sub coil is appropriately selected.