Nsk Corporation

Nsk Steering Systems Co., Ltd.

Atsushi Horikoshi

Hayao Watanabe

Takaaki Sekine

Shigeo Shinohara

Takeshi Senba

Nobuyasu Kanekawa

Seiichi Kobayashi

Kenji Mori

Shoji Sasaki

Shigeru Endo

Yusuke Kikuchi

Tetsuro Otsuka

Masahiro Miyashita

Satoshi Ozaki

Hideaki Kawada

Yuho Aoki

Yoshihiro Aosaki

Tamotsu Oumi

Hisayoshi Koiwai

Yasuhiro Shimizu

Keiji Kashimoto

Atsushi Ooshima

Tetsuya Kodama

Naoki Hyoudou

Masahiro Okutani

Mitsuo Shimoda

A motor control apparatus includes a motor current shutoff unit inserted between a multi-phase inverter circuit and a multi-phase electric motor to shut off a current for each of plural phases, the inverter circuit including an arm for each of the plural phases, a redundant arm unit including one or more arms, a connection selecting unit selecting which one of windings of the electric motor is to be connected to each of the one or more arms of the redundant arm unit, an abnormal arm detection unit detecting an abnormality in each of the plural phases of the inverter circuit, and an abnormality control unit shutting off connection between an abnormal arm and the motor when the abnormal arm detection unit detects the abnormal arm, and connecting the one or more arms of the redundant arm unit to a winding of the motor shut off.

Motor control apparatus, electric power steering apparatus and vehicle using the same

A motor control apparatus includes a steering column having inserted therein a steering shaft to which steering torque is transmitted, a reduction gear box coupled to the steering shaft, and an electric motor that transmits a steering assisting force to the steering shaft via a reduction mechanism in the reduction gear box. The electric motor and its control unit including a control board mounted with a control circuit, are provided side by side in the reduction gear box. A connection terminal of the electric motor is electrically connected to the control unit directly. This minimizes a connection distance between the control unit and the electric motor.

Electric power steering apparatus and method of assembling the same

Since an abnormality is judged by executing a square calculating process with respect to sin &#x3b8; and cos &#x3b8; for detecting an abnormality in an angular resolver, a processing time is elongated, and a burden to a CPU is great. Since the invention prepares a map which can judge whether the combination of sin &#x3b8; and cos &#x3b8; is normal or abnormal, and judges by mapping the combination of the detected sin &#x3b8; and cos &#x3b8;, a process can be easily executed, a processing speed is high, and a burden to the CPU can be reduced. Further, an assist can be maintained by controlling a motor by a rectangular wave current by detecting a rotation angle signal at low resolution level, such as Hall sensors arranged around the motor.

Control unit for electric power steering apparatus

In a resolver digital converter comprising a resolver, a resolver digital conversion part, and an excitation signal generation part, the resolver digital converter for inputting an excitation signal generated in the excitation signal generation part to the resolver and inputting resolver signals outputted from the resolver to the resolver digital conversion part, a locus in which amplitude of a sine component signal among the resolver signals sin(&#x3b8;), cos(&#x3b8;) outputted from the resolver is plotted as the ordinate axis and amplitude of a cosine component signal is plotted as the abscissa axis is approximated by a polygon and when the locus matches with sides of the approximated polygon, it is determined that the resolver is in a normal state and when the locus does not match, it is determined that the resolver is in a failure state.

Resolver digital converter

A sealed actuator includes a motor stator having rotation-drive magnetic poles; a motor rotor arranged so as to confront magnetic pole surfaces of the motor stator while interposing a small distance therebetween and rotatably supported through roller bearings; and displacement detecting means for measuring displacement of the motor rotor. A partition wall made of a nonmagnetic metal is disposed in a clearance between the motor stator and the motor rotor, so that the inner space where the motor stator is disposed is hermetically covered. The bearings are disposed at both sides of the partition wall in the axial direction so that the load applied to the bearings are directly received by a housing. At least a part of the partition wall is reinforced by reinforcing members and a mold agent is charged into the space on the motor stator side.

Sealed actuator

A linear motor includes a row of permanent magnets fixed at a position above a stator, and a plurality of magnetic pole members fixed at a position below a movable member. The row of permanent magnets is formed from N poles and S poles alternately arranged at given intervals. The plurality of magnetic pole members extend toward the row of permanent magnets and in a vertical direction and have the same height. The extremities of the magnetic pole members oppose the row of permanent magnets via an air gap. The magnetic pole members are coated with insulators, and a former-wound coil is fitted around the insulator. The part of the magnetic pole member coated with the insulator, except for the extremity thereof, is made thin by the amount corresponding to the thickness of the insulator.

Linear motor

Growing community of inventors

Kanagawa, Japan

Atsushi Horikoshi