Minebea Company, Limited

Minebea Kabushiki-kaisha

Toshisada Koyama

Mutsumi Matsuura

Takashi Sano

Yasuhiro Mouri

Rikuro Obara

Taiichi Miya

Kunihiro Tsuchiya

Akio Okamiya

Akimi Furukoshi

Hiroyuki Yajima

Yoshihito Osanai

Taro Kasahara

Yasuhiro Mori

Kenichi Goto

To supply a pivot assembly for hard disk drive use that can reliably fix a seal member and solve the problem of out gas, thus reducing the expense and time incidental to the pre-load of a ball bearing. Ball bearings have been joined to both ends of a shaft, and on the outer circumference of these ball bearings, the spacer part is joined to a sleeve disposed between both ball bearings, and a seal member that covers the outer end of the ball bearing has been fixed to the outer circumference of the shaft by laser welding. Because the seal member is fixed by laser welding, the seal member can be reliably fixed and the problem of out gas from the seal member can be solved.

Pivot assembly for hard disk drive use

A rotation angle sensor includes: (a) a multi-resolver housing with a high precision structure; (b) stator terminals that do not cause deformation or loosening of terminal pins from the substrates to which they are attached; and (3) a signal line connection structure that is not affected by thermal stress. The housing () includes divisional housings (), and one resolver is installed in each of the divisional housings (). The divisional housings () are assembled by aligning respective openings therein in an axial direction. The lead lines of stator windings are connected to printed circuit substrates () installed on insulators (), and pins () connect the printed circuit substrates () to a connecting signal output line via flexible connectors ().

Multi-resolver rotation angle sensor with integrated housing

A pivot assembly for use in a hard disk drive, in which ball bearings are placed at both ends of a shaft, and a spacer is disposed between outer rings of the ball bearings. The spacer is fixed to the outer rings by laser welding.

Pivot assembly preloaded by laser welding for hard disk drive use

A variable reluctance resolver has a rotor with magnetic poles with 2&#xd7; or greater axis combination angles, and is structured so that reliable and accurate zero point detection can be carried out. Concave and convex portions are provided on at least two, but fewer than all, of the magnetic poles of the rotor, and the zero point detection winding is provided on a plurality of electrical poles of the stator. Two or more zero point detection signals are generated simultaneously by a plurality of zero point detection windings. Therefore, even if a portion of the zero point detection signals is lost, the zero point can still be identified based on the correlation between the two or more zero point detection signals.

Variable reluctance resolver including rotor with multiple detection portions

The bearing device contains two rolling bearings installed on a shaftand a preload is applied to the inner ring of the rolling bearings. The respective dimension for the two rolling bearing inner rings is shortened on both sides in the orientation of the width dimensions of the inner ring, centered on the grooves for the inner ring, with each being set smaller than the dimension of the outer rings. The difference in dimensions is double the difference in the dimensions capable of eliminating rattling of the rolling bearings, when a preload is applied to the outer edge of the inner ring. The outer rings and races are respectively formed to be in a position at half the width dimension of the inner ring from the outer edges of the two outer rings for the two rolling bearings.

Bearing device

A pivot bearing includes a stepped shaft having an enlarged diameter shaft portion and a reduced diameter shaft portion; a plurality of balls of a lower row are interposed between the enlarged diameter shaft portion and a sleeve outer ring surrounding the enlarged diameter shaft portion; a ball bearing including inner and outer rings and a plurality of balls interposed therebetween is provided around the reduced diameter shaft portion so that the inner ring is secured around the reduced diameter shaft portion while applying an appropriate pre-load on the upper end surface of the inner ring, and the outer ring is urged to contact the lower surface thereof intimately onto the upper surface of the sleeve outer ring. The pivot bearing has a reduced number of parts, is facilitated in incorporation into a swing arm, and is expected to be manufactured at a reduced cost.

Pivot bearing for a swing arm of a hard disk drive device

A rotation angle sensor and a method of winding a rotation angle sensor involve a single electrical wire that is wound from a rotor transformer to a magnetic rotor. The magnetic rotor is axially spaced on a shaft from the rotor transformer. A notch is formed in a wall of a bobbin of the rotor transformer to permit the wire to pass from the rotor transformer to the magnetic rotor. The ends of the single wire are electrically connected together at a junction, and the junction is fixed to the rotor transformer with resin.

Rotation angle sensor having single wire windings and method for winding a rotation angle sensor

An apparatus for a pivot assembly that can strongly and reliably fix a sleeve to an outer ring, and in addition, that can also solve the problem of out gas. Ball bearingare mated to both ends of a shaft, and to the outer circumference of these ball bearings, an inner wall partmates a sleeve disposed between both ball bearings, and the sleevewas fixed by laser welding to the outer ringof the bell bearings

A pivot bearing assembly that can be easily assembled without deformation and featuring a lower amount of outgas and thermal compensation of bond strength. Further, with the pivot bearing assembly, a bearing inner ring and a shaft and a bearing outer ring and a housing are slidingly fitted, bonded and secured to each other with an ultraviolet curing type anaerobic adhesive having a high vitrification temperature, respectively.

Pivot bearing assembly and a method of manufacturing the same

In order to facilitate fixing a pivot assembly to an actuator block and to obtain the stable coaxiality, a screw hole passing from the outside is provided towards a fitting hole into which the pivot assembly is inserted. Moreover, a set screw is screwed into a screw hole to press a sleeve of the pivot assembly, which has been inserted into the fitting hole with an end portion of the set screw. The sleeve pressed at a pressure F with the set screw is clamped and fixed by a inside wall surface of the fitting hole and the end portion of the set screw revealing in the inner side of the fitting hole.

Actuator block

A pivot bearing assembly comprises a shaft having a main body portion and a reduced portion integrally and coaxially formed therewith, an outer ring-sleeve member coaxially surrounding the shaft, a first bearing arranged between the reduced portion of the shaft and the outer ring-sleeve member, a second bearing arranged between the main body portion of the shaft and the outer ring-sleeve member and a tolerance ring mounted on the outer peripheral surface of the outer ring-sleeve member. The inner ring of the second bearing is a part of the main body portion of the shaft. The outer ring-sleeve member can comprise an outer ring and a sleeve tightly mounted on the outer ring or an outer ring portion and a sleeve portion surrounding the outer ring and integrally formed therewith.

Pivot bearing assembly

A pivot assembly for sustaining a magnetic head, a head suspension and an actuator block pivotally parallel to magnetic disks oscillates slowly. Hence the invention has been made in light of examining a sealing structure for retaining sufficient capability of preventing a leakage of lubricant and retaining sufficient capability of preventing a contamination of lubricant, characterized in that retaining required sealing capabilities, an annular shield plate is secured to the shaft, achieving pivot assembly manufacturing cost by reducing machining process and a number of sealing members.

Pivot assembly for driving a magnetic head

Spindle motor and pivot assembly

A pivot bearing of the present invention comprises inner rings, outer rings surrounding the inner rings and rollable balls arranged between the inner and outer rings. This pivot bearing does not have a sleeve which is provided on the outer rings of a conventional pivot bearing. Each of the outer rings is made thicker substantially by the thickness of the sleeve of the conventional pivot bearing than the outer rings of the conventional pivot. The other components of the pivot bearing according to the present invention than the outer bearings use commercially available components or standardized components manufactured in the ordinary manufacturing line at ball bearing manufacturers' factories. Thus, a simple, inexpensive and precise pivot bearing can be manufactured.

Pivot bearing

A hard disk drive is made small in size, large in storage capacity and high in data reading/writing speed. Two actuator blocks ( ) are fixed to a sleeve A of a first pivot and sleeve ( B) of a second pivot, respectively. Position of magnetic heads to be accessed to different magnetic disks are controlled independently by the actuator block basis. Therefore, it is possible to distribute the reading/writing processing to the plurality of magnetic disks and perform these processing in parallel, to thereby increase the data reading/writing speed while increasing the storage capacity.

Growing community of inventors

Miyota-machi, Japan

Toshisada Koyama