Provided is a slide bearing (bearing sleeve (8)), comprising an oxidized green compact in which particles (11) of metal powder are bonded to each other by an oxide film (12) formed on surfaces of the particles (11). The oxidized green compact has a bearing surface (A, B) configured to slide, through intermediation of a lubricating film, relative to a mating member (shaft member (2)) to be supported. The bearing surface (A, B) has a large number of opening portions (13a), and the large number of opening portions (13a) and inner pores (13b) are interrupted in communication therebetween by the oxide film (12).

A fluid dynamic bearing device prevents an oleophobic agent from wetting and spreading to a tapered seal portion, including lubricating oil C filled in a condition in which the oil is separated sandwiching a separator portion 240 holding a gas layer arranged between two conical bearing members 201, and two primary tapered seal portions 230 each connecting to one of both ends along an axial direction of the separator portion 240, wherein width in a radial direction of the two primary tapered seal portion 230 decreases as each approaches toward the two conical bearing members 201, a gas-liquid interface of the lubricating oil C is located each of the two primary tapered seal portions 230, an oleophobic agent blocking portion 250 is arranged at each of both ends in an axial direction of the separator portion 240, a separator central portion 244 is arranged between the oleophobic agent blocking portions 250 of the separator portions 240, and an oleophobic coating is formed at least at the separator central portion 244 of the separator portion 240.

A rolling bearing capable of achieving reduction in torque is provided. The rolling bearing includes an inner ring and an outer ring disposed coaxially with each other, a rolling element disposed between the inner ring and the outer ring, a seal member configured to cover an area between the inner ring and the outer ring from an outside in an axial direction, and filled grease disposed between the rolling element and the seal member. The filled grease includes a first ring-like part which extends to form a circumferential shape centering on a common axis of the inner ring and the outer ring, and which has contact with one of the inner ring and the outer ring, and a second ring-like part which extends to form a circumferential shape centering on the common axis, which is connected to the first ring-like part at an outer side in the axial direction, and which has contact with the seal member.

A tolerance ring having a first axial end, a second axial end, and a central axis, the tolerance ring including an annular band; a plurality of protrusions, all of the plurality of protrusions extending from the annular band; and a guide portion extending from the annular band towards the first axial end of the tolerance ring, where the guide portion includes a guide surface that is curved in an axial section.

A bearing grease includes a base oil and a thickener, and the base oil includes mineral oil and poly-α-olefin. The poly-α-olefin may be a blend of poly-α-olefin having a kinetic viscosity higher than that of the mineral oil and poly-α-olefin having a kinetic viscosity equal to or lower than that of the mineral oil, and the kinetic viscosity of the base oil at 40° C. is in a range of 40 through 90 mm.sup.2/s. The amount of the poly-α-olefin by mass in the base oil is greater than the amount of the mineral oil by mass in the base oil. The worked penetration of the grease is in a range of 200 through 250. The grease reduces flying grease and outgas and has superior low-temperature characteristics.

A disk drive is provided with an enclosure and a disk mounted for rotation within the enclosure. The disk drive is also provided with a head mounted for rotation within the enclosure and adapted to engage the disk, a housing defining a cavity extending along an axis within the enclosure, and a shaft received within the cavity, mounted for rotation about the axis and coupled to one of the disk and the head. The disk drive is also provided with a bearing and a bearing seat. The bearing is formed generally spherical, oriented in a non-rolling configuration along the axis, and secured to one of the housing and the shaft. The bearing seat has a surface secured to the other of the housing and the shaft and biased to engage the bearing, wherein at least one of the bearing and the surface includes a low-friction coating formed thereon.

A fluid dynamic bearing device prevents an oleophobic agent from wetting and spreading to a tapered seal portion, including lubricating oil C filled in a condition in which the oil is separated sandwiching a separator portion 240 holding a gas layer arranged between two conical bearing members 201, and two primary tapered seal portions 230 each connecting to one of both ends along an axial direction of the separator portion 240, wherein width in a radial direction of the two primary tapered seal portion 230 decreases as each approaches toward the two conical bearing members 201, a gas-liquid interface of the lubricating oil C is located each of the two primary tapered seal portions 230, an oleophobic agent blocking portion 250 is arranged at each of both ends in an axial direction of the separator portion 240, a separator central portion 244 is arranged between the oleophobic agent blocking portions 250 of the separator portions 240, and an oleophobic coating is formed at least at the separator central portion 244 of the separator portion 240.

A fluid dynamic bearing device 1 includes: a shaft member 2; a bearing sleeve 8 that has the shaft member 2 inserted into the inner periphery thereof; a housing 7 that holds the bearing sleeve 8 on the inner periphery thereof and has a bottomed cylindrical shape having an opening at an end portion on one axial side; and a seal member 9 provided at the opening of the housing 7. The seal member 9 has a disk portion 9a disposed on one axial side of the bearing sleeve 8, and a protrusion (cylindrical portion 9b) protruding to the other axial side from an outer diameter end of the disk portion 9a. An outer peripheral surface 9c of the seal member 9 is fixed to an inner peripheral surface 7a1 of the housing 7.

A ball bearing includes an inner ring, an outer ring, a plurality of balls rollably provided between the inner ring and the outer ring, and a cage configured to hold the plurality of balls at equal intervals in a circumferential direction. The cage includes a plurality of pockets configured to hold the balls. The plurality of pockets include at least two types of pockets including a first pocket and a second pocket. A gap on each of an outer circumferential surface side and an inner circumferential surface side of the cage between the ball and an inner circumferential surface of the second pocket is larger than a gap on each of the outer circumferential surface side and the inner circumferential surface side of the cage between the ball and an inner circumferential surface of the first pocket.

According to one embodiment, a disk device includes a disk-shaped recording medium, a base accommodating the recording medium, the base including a bottom wall, a sidewall on a peripheral portion of the bottom wall, and a rib on a part of an upper surface of the sidewall, a first cover on a part of the upper surface of the sidewall, and a second cover on a first surface of the rib and above the first cover. The rib includes a first region with a first width, a second region with a second width less than the first width, and the first surface with a fixed width around an entire circumference of the rib. The first region and the second region are located corresponding to a side portion of the recording medium.