Matsushita Electric Industrial Co., Ltd.

Hiroyoshi Teshima

Hironobu Nishida

Makoto Hasegawa

Hiroyasu Fujinaka

Kouji Kuyama

Miyuki Furuya

Shigenori Uda

Akihide Matsuo

Kazuya Nakamura

A plate form housing includes a winding. A sleeve which is a bearing is provided in a bearing mounting hole formed in the housing so as to be in the central position of the winding. A shaft mounting a rotor having a magnet confronting the winding supported on the sleeve. A magnetic disk is provided at the end of the shaft. The sleeve is fixed in the bearing mounting hole of the housing by using a conductive adhesive. In this manner, discharge breakdown or destruction of the information recorded in a magnetic disk due to electric charge generated in the magnetic disk rotating at high speed is prevented.

Magnetic disk driving apparatus with bearing fixed with conductive adhesive

A spindle motor includes a housing, a rotor hub section arranged rotatably with respect to the housing, a sleeve section, a shaft fit rotatably in the sleeve section, and a thrust plate mounted to the sleeve section opposite to an end surface of the shaft. A thrust dynamic pressure bearing has a dynamic pressure bearing groove formed on the thrust plate, the thrust dynamic pressure bearing including lubricating oil at a relative slide interface between the thrust plate and the end surface of the shaft. The dynamic pressure bearing groove and a circumferential portion of the thrust plate are formed by etching, and a radial dynamic pressure bearing includes lubricating oil at a peripheral interface between the shaft and the sleeve section.

Spindle motor having an etched thrust plate and a process of making the spindle motor by etching of the thrust plate

In a thin type flexible disk drive motor, in order to improve undesirable jittering of rotation, an inertia ring of larger diameter than that of the rotor frame is fixed immediately under the rotor. The inertia ring consists of a short cylinder part of the larger diameter to be fixed under the rotor frame and a flange part of the diameter not smaller than that of FG (frequency generation) magnet part. The disk drive motor also has a drive pin engaging assembly that allows a drive pin to be secured within a hub of the flexible disk while stabilizing the drive pin and after disk chucking.

Motor for driving information medium

A disk driving apparatus using a dynamic pressure-type bearing device of an oil lubrication type, wherein the bearing device includes a housing main body, a sleeve part fixed to the housing main body, a rotor part relatively rotatable to the housing main body, a shaft having a spherical front end clamped to the rotor part, a bottom plate at an end face of the shaft and a thrust member interposed between the shaft and the bottom plate has a dynamic pressure radial bearing constructed by the shaft and the sleeve part and having herringbone grooves formed at either of the shaft and sleeve part, the thrust member being formed of a high polymer, and a thrust pivot bearing constructed by the thrust member set at the bottom plate secured to one side of the sleeve part and one end of the shaft.

Disk driving apparatus using dynamic pressure-type bearing device

Motor

A spindle motor includes a housing, a rotor hub section arranged rotatably with respect to the housing, a sleeve section, a shaft fit rotatably in the sleeve section, a thrust plate mounted to the sleeve section and opposite to an end surface of the shaft. A thrust dynamic pressure bearing has a dynamic pressure bearing groove formed on the thrust plate, the thrust dynamic pressure bearing including lubricating oil at a relative slide interface between the thrust plate and the end surface of the shaft. The dynamic pressure bearing groove and a circumferential portion of the thrust plate are formed by etching, and a radial dynamic pressure bearing includes lubricating oil at a peripheral interface between the shaft and the sleeve section.

Spindle motor having a thrust plate etched to form a dynamic pressure

A disk driving spindle motor wherein a hub portion having a flange portion on which a disk is to be clamped is supported for rotation relative to a housing body and a rotor frame is attached to the flange portion, the hub portion being driven for rotation by magnetic repulsive action produced between the housing body and the rotor frame. A clearance extending from the outer to the inner periphery of the flange portion is formed between the abutment surfaces of the flange portion and the rotor frame. This structure results in decreased warping of a disk attached to a disk support surface.

Disk driving spindle motor

In a thin type flexible disk drive motor, in order to improve undesirable jittering of rotation, an inertia ring of larger diameter than that of the rotor frame is fixed immediately under the rotor. The inertia ring consists of a short cylinder part of the larger diameter to be fixed under the rotor frame and a flange part of the diameter not smaller than that of a FG (frequency generation) magnet part. The disk drive motor also has a drive pin engaging assembly that allows a drive pin to be secured within a hub of the flexible disk while stabilizing the drive pin and after disk chucking.

Disk drive motor having a drive pin assembly which facilitates

A spindle motor has a tapped hole formed in the end surface of a rotor hub at the center of rotation of the rotor hub. A clamping member presses a disk against a disk holding surface of the rotor hub by a clamp screw threaded in the tapped hole. Since the disk is clamped through a clamping member by threading and tightening one clamp screw, the clamping operation is efficiently carried out and disk imbalance due to the clamping clamp screw is decreased.

Spindle motor

A dynamic pressure bearing spindle motor includes a housing; a sleeve fixed to the housing and having a projecting lip; a rotor hub rotatable with respect to the housing and having a stopper which is engageable with the projecting lip; a shaft fixed to the rotor hub and rotatably inserted into the sleeve; a thrust plate attached to the sleeve so as to be opposed to an end face of the shaft; and lubricating oil provided between the thrust plate and the end face of the shaft to form a thrust bearing and also provided between the shaft and the sleeve to form a radial dynamic pressure bearing. The stopper is put into engagement with the projecting lip of the rotor hub when the rotor hub moves in a thrust direction, thereby preventing the rotor hub from coming off from the sleeve, and wherein dimensions of the motor satisfy the expression a&lt;2d&lt;b where an outer diameter of the sleeve excluding the projection lip is a, an outer diameter of the projecting lip is b, and a radius of curvature of an inner periphery of the stopper is d.

Dynamic pressure bearing spindle motor

In order to prevent clouding of a hard disc and a polygon mirror, a tin-free electrodepositing coating composition is used as an insulating coated film of a motor for driving the hard disc and polygon mirror.

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Saihaku-gun, Japan

Hiroyoshi Teshima