Hitachi, Ltd.

Hitachi Taga Engineering, Ltd.

Jun Matsubayashi

Katsutoshi Nii

Kazuhiko Kawaike

Satosi Uno

Fumio Tajima

Kunio Miyashita

Seikichi Tanno

Takao Uematsu

Tomio Yoshida

Kuniaki Kubokura

Yoshiharu Honma

Kazuaki Takada

Eiji Toyoda

Ran Ito

There is disclosed a polygon mirror motor in which an annular projection is formed on an upper surface of a rotor support member supporting a polygon mirror, and the annular projection supports a part of a lower surface of the polygon mirror. Radial bearings supporting a shaft of the motor have a plurality of oil grooves extending over about a half of the dimension of the radial bearing in a thrust direction. A magnetic fluid is filled in a space defined by the shaft, a support tube of a bearing support member and the radial bearings.

Vertical motor, method of manufacturing same, polygon mirror motor using

A sliding bearing an an end ring are mounted on a housing. A magnetic fluid sealing member comprises a permanent magnet and a magnetic fluid. A space is formed between the magnetic fluid sealing member and a lubricating fluid. A shaft has projection member or the end ring forms a spiral groove on an inner peripheral portion. The projection member of the shaft or the spiral groove of the end ring is disposed in an opposite position of the magnetic fluid sealing member. A magnetic fluid flow is disturbed by the projection member of the shaft or the spiral groove of the end ring according to a rotation of the shaft, then a magnetic fluid film is destructed instantaneously and the pressure at the space lowers. Air in the space is discharged from the housing. The scatter degree of the magnetic fluid is made slightly.

Magnetic fluid bearing apparatus and motor having magnetic fluid bearing

A rotor of a permanent magnet type synchronous motor facing a stator having a number of slots comprises a rotor core fixed to a motor shaft and an even number of permanent magnets in a circumferential direction of the rotor core. Projecting portions are formed in the shape of a protruding portion of the rotor core over each permanent magnet. The width (A) of each projecting portion is different from the pitch (B) of the slots of the stator. A position detector for detecting the permanent magnet position of the rotor comprises detectors of the normal rotation and other detectors of the reverse rotation. These detectors are arranged having predetermined phase differences (.alpha., .beta.) to a center line. A pattern generating circuit is provided for switching the conducting position to the stator winding corresponding to the phase differences.

Permanent magnet reversible synchronous motor

A friction material made of a molded cork, a friction surface of which is covered with a liquid or semi-solid lubricant layer including a solid lubricant layer comprising a solid lubricant having a larger particle size and a solid lubricant having a smaller particle size and filling vacant spaces between the larger-sized solid lubricant in dense form, affords a long service life when used in a power controlling apparatus which can transmit power and/or change rotation speed by applying friction and using a friction material.

Power controlling apparatus using friction material

Growing community of inventors

Naka, Japan

Jun Matsubayashi