Tdk Corporation

Nobuyuki Shimbo

Koji Mitake

Masashi Gotoh

Toshihiro Kuroshima

Michio Ishikawa

Fumio Ono

Takatoshi Oyama

Junichi Ishiwata

A motor deviceincludes an SPM motorthat includes a statorincluding an iron coreand a plurality of windingswound on the iron core, and a rotorwhich is rotatable with respect to a rotation axis and in which a plurality of permanent magnetsare mounted along a circumferential direction to form a plurality of magnetic poles in the circumferential direction; and a power supply unitthat supplies a current to the plurality of windingsof the SPM motor. Each of the plurality of magnetic poles is oriented such that directions of axes of easy magnetization are concentrated toward a stator side, and the current supplied from the power supply unit is a trapezoidal wave.

Motor device

In an IPM motor, since an end surface portion which is a pressed powder compact made of soft magnetic powder has a higher electrical resistivity than an electrical resistivity of a main body portion made of a laminated steel sheet, compared to when the electrical resistivity of the end surface portion is the same as the electrical resistivity of the main body portion, the occurrence of an eddy current in the end surface portion is further prevented. For this reason, in the IPM motor, a deterioration in efficiency caused by an eddy current loss is prevented, and an improvement in efficiency is realized.

Rotating electrical machine

In an IPM motor, since a first portion which is a pressed powder compact made of soft magnetic powder and has a lower magnetic permeability and a lower saturation magnetic flux density than those of a main body portion made of a laminated steel sheet is replaced and disposed in the vicinity of an inner arc side portion of a right end portion of a permanent magnet, local demagnetization is prevented.

This arcuate magnet piece includes: coupling side surfaces which are coupled with other adjacently joined arcuate magnet pieces; a curved inner peripheral surface; and a curved outer peripheral surface which faces the inner peripheral surface. The coupling side surfaces include tip surfaces which intersect, at prescribed angles, tangents to the direction of curvature of the outer peripheral surface. The coupling side surfaces are polarized such that, in cases when the gaps formed with the coupling side surfaces of the other arcuate magnet pieces are disposed so as to be substantially parallel, the magnetic poles of the other joined arcuate magnet pieces are different.

Arcuate magnet piece, permanent magnet piece, permanent magnet assembly, permanent magnet application device, and motor

A Hall effect sensing apparatus for a moving object includes a moving magnetic member having concave and convex segments alternately at is periphery, a detector including a pair of Hall effect elements for converting a magnetic signal to an electric signal, a processing circuit for processing signals from the detector, a magnet for providing magnetic field to the Hall effect elements, and a yoke provided in close proximity to the magnet. The yoke has a smaller surface area than that of the magnet and is movably arranged so as to adjust detecting sensitivity of the sensing apparatus. Therefore, even though there are some variances of magnetic characteristics in the detector, the detecting sensitivity of the sensing apparatus can be adjusted to an optimum level by observing a signal outputted from the processing circuit.

Growing community of inventors

Tokyo, Japan

Nobuyuki Shimbo