Minebea Company, Limited

Minebea Mitsumi Inc.

Kunihiro Tsuchiya

Atsushi Kaneko

Tadashi Uchida

Toshisada Koyama

Shinya Ohnuma

There is provided a bearing device including: a tubular sleeve; a shaft held inside the sleeve; and a first bearing, a second bearing, a third bearing, and a fourth bearing, rotatably holding the shaft with respect to the sleeve and arranged in this order in an axial direction. An outer circumferential surface of an outer ring of each of the first to fourth bearings is fixed to an inner circumferential surface of the sleeve, a gap is provided between inner circumferential surfaces of inner rings of the second and third bearings and the shaft, and a spring applying a constant pre-load is provided between the inner rings of the second and third bearings.

Bearing device with pre-load configuration, method for producing same, and hard disk drive device

A pivot assembly bearing apparatus includes: a shaft extending in an axial direction, a first rolling bearing, a second rolling bearing and a first sleeve bonded to an outer peripheral surface of the first outer ring of the first rolling bearing, a second sleeve bonded to an outer peripheral surface of the second outer ring of the second rolling bearing and a spacer abutting on a lower end surface of the first outer ring and an upper end surface of the second outer ring. A part of the first sleeve protruding downwards in the axial direction from the first outer ring is bonded to the spacer, and a part of the second sleeve protruding upwards in the axial direction from the second outer ring is bonded to the spacer.

Pivot assembly bearing apparatus

A technique for swinging swing arms stably by reducing vibrations of bearing units due to resonance in rolling bearings is provided. A pivot assembly bearing deviceincludes a shaftextending in an axis Ydirection, and an upper bearing unitand a lower bearing unitthat are provided along the axis Ydirection of the shaft. A natural frequency of the upper bearing unitand a natural frequency of the lower bearing unitin the axis Ydirection of the shaftdiffer from each other.

Pivot assembly bearing device and pivot assembly bearing device fabrication method

A pivot assembly bearing device includes a shaft having an outer peripheral surface and a rolling bearing fixed to the shaft. An annular sealing surface axially overlapping with at least a part of an end surface of the rolling bearing is provided on an axially outer side of the rolling bearing. An oil-repellent film is annularly formed on at least one of the sealing surface and a part of the outer peripheral surface of the shaft located axially outward from the rolling bearing.

Pivot assembly bearing device

In order to prevent leaking of lubricant, the bearing device includes a rolling bearing having an outer ring and an inner ring, a shaft fixed to the inner ring, and a sleeve fixed to the outer ring. A flange part is formed on at least one end part of the shaft. The flange part includes a disk part extending from the shaft toward an outside in a radial direction and a cylindrical part extending from the disk part along an axial direction. The cylindrical part is disposed at an outside of the outer ring, and a labyrinth gap which bends at two places is formed by gaps.

Bearing device

A pivot assembly bearing includes a shaft, a sleeve provided coaxially with the shaft, and a pair of rolling bearings arranged to be separated from each other in an axial direction between the shaft and the sleeve. The sleeve includes a ventilation path configured to communicate a region surrounded by the shaft, the pair of rolling bearings, and the sleeve with the outside of the sleeve.

Pivot assembly bearing and hard disk drive device

A pivot assembly bearing includes: a sleeve, a shaft inserted into the sleeve, a pair of rolling bearings disposed between the sleeve and the shaft such that the rolling bearings are separated apart from each other in an axial direction. The rolling bearings include an inner ring fixed to the shaft, an outer ring fixed to the sleeve, and a rolling element provided between the inner ring and the outer ring. In at least one of the rolling bearings, a first sealing member contacts an end face of the outer ring facing an outer side in the axial direction. Thus, a first labyrinth gap between the first sealing member and an end face of the inner ring facing the outer side in the axial direction, and a second labyrinth gap between the first sealing member and the shaft are formed.

Pivot assembly bearing and disk drive device

A bearing device includes a shaft having an axis, plural rolling bearings arranged at axially separated positions and rotatably supporting the shaft, a first cylindrical member for supporting the rolling bearings therein and having a first screw on a part of an outer surface thereof, a second cylindrical member having a second screw engaging with the first screw on an inner surface thereof and mounted to the outer surface of the first cylindrical member by engaging the first screw with the second screw, a restricting member provided on the outer surface of the second cylindrical member for preventing relative axial movement of the second cylindrical member with respect to the first cylindrical member when a portion of the second member contacts the restricting member.

Bearing device and swing arm assembly for magnetic disk

A pivot assembly bearing having a bearing inner ring, a shaft, a bearing outer ring, a housing, and an UV curable anaerobic adhesive fixing the bearing inner ring to the shaft, and the bearing outer ring to the housing, wherein the adhesive includes 15 to 25% of urethane acrylate, 45 to 55% of acrylic acid diester, less than 3% of acrylic acid monomer, 15 to 30% of hydroxyalkylmethacrylate, less than 3% of anaerobic catalyst, and less than 3% of photopolymerization initiating agent, and in addition, a coloring agent, if necessary. The pivot assembly bearing reduces outgas, shortens adhesive curing time, and no tack at the adhesive surface is obtained.

Pivot assembly bearing

A pivot assembly that narrows the gap of the seal member as much as possible and can effectively restrain the diffusion of gas and dirt from the inside, and, moreover, can also solve the problem of out gas from a hub cap, is presented. The pivot assembly has ball bearings mated to both ends of a shaft, a spacer mated to a sleeve disposed between both ball bearings at the outer circumferences of these ball bearings, and has a hub cap member that covers the outside end face of the ball bearings at one end of the shaft. The hub cap is laser welded to the outer circumference of the shaft and the inner circumference of the sleeve, and after laser welding, is thin-width cut by a laser along the entire circumference at the radial middle part.

Apparatus for the sealing of a pivot assembly used in a hard disk drive

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.

Growing community of inventors

Tomioka, Japan

Kunihiro Tsuchiya