Hitachi Metals, Ltd.

Other

Toshiko Takahashi

Masahiro Mita

Masahiro Masuzawa

Fumio Kimura

Kenichi Kitta

Takehiro Takahashi

Disclosed is a permanent magnet generator incorporated in a 3.5&Prime; diskette that can be used as an input/output adapter for memory cards that can generate a power generation output of 40 mW or more when the rotor of the generator is rotated at 300 rpm. The permanent magnet generator has such a construction that rotor magnetic poles are provided only on one end face of a disc-shaped permanent magnet serving as a rotor, a plurality of stator magnetic poles are provided only on that end face of the permanent magnet in such a manner as to face the rotor magnetic poles, and a soft magnetic hub is fixedly fitted to the other end face of the permanent magnet. Even when a bonded NdFeB magnet is used as the permanent magnet, a sufficient power can be produced.

Thin type permanent magnet generator and diskette incorporating same

A diskette incorporating a flat disk-shaped permanent magnet generator is disclosed. This permanent magnet generator comprises a rotor having a permanent magnet that can rotate together with a hub; the permanent magnet having a plurality of rotor magnetic poles on the circumference thereof, and a stator comprising a plurality of magnetic pole teeth having on one end thereof stator magnetic poles that can face the rotor magnetic poles via a magnetic gap. The magnetic pole teeth extend from the stator magnetic poles outside of the rotor, with stator coils wound on the extended portions of the magnetic pole teeth and the outside ends of the magnetic pole teeth connected to each other by a back yoke. The thickness of the outward extending magnetic pole teeth is smaller than the thickness of the permanent magnet. The diskette should preferably be a 3.5&Prime; floppy disk.

Diskette incorporating a permanent magnet generator having a stator with magnetic pole teeth that are axially thinner than a permanent magnet that cooperates with the stator

A permanent magnet generator incorporated in a diskette that can be inserted into a floppy disk drive is disclosed. In the permanent magnet generator, electric power is generated as a rotor is caused to rotate at a revolution twice to ten times as high as that of the drive shaft of a floppy disk drive by transmitting the rotation of the drive shaft to a rotor via a speed increasing mechanism incorporated in a diskette. Since the cogging torque of the generator is reduced, the rotor can be caused to rotate with a small drive torque. This allows the generator to produce a high output.

Diskette incorporating permanent magnet generator

In a diskette, such as a 3.5&Prime; floppy disk, having adjoiningly a permanent magnet generator and a space for inserting a memory card with a magnetic stripe, the affection of leakage magnetic flux from the generator permanent magnet to the memory card and another floppy disk that may be put in the neighborhood of the diskette is substantially eliminated and the generator output is increased. A magnetic shield is disposed only at the portion corresponding to the magnetic stripe of the memory card on a generator housing or a partition between the generator permanent magnet and the memory card space. A magnetic shield ring with a diameter substantially equal to or larger than the outside diameter of the permanent magnet is fixed or pasted on one side end of the rotor permanent magnet adjacent to one of the ends of the diskette case.

Diskette incorporating permanent magnet generator with low leakage flux

A permanent magnet generator is so thin as to be incorporated in a 3.5&Prime; diskette. The generator having so low cogging torque that can be rotated smoothly even by a low torque driving source as a 3.5&Prime; FDD to generate stable output is disclosed. It has stator magnetic poles facing via a magnetic gap an outer circumferential surface of the stator permanent magnet having a plurality of magnetic poles on it. One to six of the stator magnetic poles are removed and instead of the removed magnetic poles provided is a soft magnetic piece to face the rotor magnetic poles. Grooves are preferably provided on the soft magnetic piece, facing the rotor magnetic poles. A notch is provided on the permanent magnet generator to avoid interference with an input/output terminal and/or a card contact terminal of the diskette for inserting a memory card.

Growing community of inventors

Fukaya, Japan

Toshiko Takahashi