Patent application number | Description | Published |
20080218023 | BRUSHLESS MOTOR AND ELECTRIC POWER STEERING DEVICE HAVING BRUSHLESS MOTOR - In a three-phase brushless motor, a rotor has a stacked structure including first to third stages which include segment magnets to which a skew process is applied. When the number of poles P in the circumferential direction is set to P, an angle of skew is set to Δ=360/(6P/2) [deg]. That is, the magnet segments are respectively arranged so that the magnet segment of the second stage is shifted by a rotating angle of Δ/3 in the circumferential direction from the magnet segment of the first stage and the magnet segment of the third stage is shifted by a rotating angle of 2Δ/3 in the circumferential direction. | 09-11-2008 |
20080224559 | BRUSH-LESS MOTOR AND ELECTRIC POWER STEERING DEVICE HAVING BRUSH-LESS MOTOR - A permanent magnet included in a rotor of a brush-less motor is a radial anisotropic magnet in which multi-poles are magnetized in the circumferential direction and is skew magnetized along the axial direction in such a manner that a surface to one end part of an upper side from a central part in the axial direction and a surface to an end part of a lower side from the central part are axially shifted by a predetermined angle in the circumferential direction from each other. In accordance with this skew-magnetization, coggings including irregularly varying components generated in the rotor owing to the three-dimensional shapes of coil ends provided at opposite ends of a tooth | 09-18-2008 |
20080283331 | VEHICLE STEERING APPARATUS - An electric motor provided in a vehicle steering apparatus includes a stator coaxially surrounding a steering shaft, an inner rotor disposed on the inner periphery of the stator, and an outer rotor disposed on the outer periphery of the stator. The facing area between the stator and the rotor can be increased by providing the inner rotor and the outer rotor in the electric motor. Consequently, the electric motor can be miniaturized while a certain output thereof is maintained. The vehicle steering apparatus can be miniaturized by miniaturizing the electric motor. | 11-20-2008 |
20090033174 | BRUSHLESS MOTOR - A brushless motor includes a stator and a rotor. The stator includes an annular stator core having teeth arranged with a spacing in a circumferential direction of the annular stator core; and coils wound around the teeth respectively. The rotor includes a rotor core and magnetic poles of segment magnets arranged annularly along a circumferential direction of the rotor core. The segment magnets are stacked at a plurality of stages in an axial direction of the rotor core. A length direction of each of the segment magnets is parallel with the axial direction of the rotor core. The following expression is satisfied: | 02-05-2009 |