Abstract: [Object] To provide a fluid dynamic bearing filled with a lubricating oil composition containing a base oil and an ionic liquid, and to provide a spindle motor in which evaporation is suppressed in the lubricating oil composition provided in the fluid dynamic bearing by incorporating the fluid dynamic bearing in the spindle motor, and thus occurrence of a read/write error in an HDD can be suppressed, and a disk drive device including the spindle motor. [Solution means] A fluid dynamic bearing filled with a lubricating oil composition containing a base oil and an ionic liquid, wherein the ionic liquid contains at least one cation selected from the group consisting of a tetraalkylphosphonium cation and a tetraalkylammonium cation and at least one anion selected from the group consisting of an imide anion, a methide anion, and borate anions represented by formulae (C-1) to (C-3).

Abstract: [Object] To provide a fluid dynamic bearing filled with a lubricating oil composition containing a base oil and an ionic liquid, and to provide a spindle motor with evaporation being suppressed in the lubricating oil composition provided in the fluid dynamic bearing by incorporating the fluid dynamic bearing in the spindle motor, and thus occurrence of a read-write error in an HDD can be suppressed, and a disk drive device including the spindle motor. [Solution means] A fluid dynamic bearing filled with a lubricating oil composition containing a base oil and an ionic liquid, the ionic liquid including at least one cation selected from the group consisting of tetraalkylammonium cations and at least one anion selected from the group consisting of borate anions represented by Formulas (C-1) to (C-3): (where in the formula, R9 to R12 each independently represent a linear or branched alkyl group.

Abstract: Object To provide a fluid dynamic pressure bearing oil and a fluid dynamic pressure bearing filled with the fluid dynamic pressure bearing oil, and to provide a spindle motor and a disk drive device including the spindle motor in which the fluid dynamic pressure bearing oil and the bearing are used, thereby suppressing adhesion of a volatile component to a magnetic disk or the like even when the fluid dynamic pressure bearing oil is volatilized, so that occurrence of HDD read/write errors can be suppressed.

Abstract: A communication apparatus receives status information including a value of a status regarding reception or non-reception of a beacon signal. The status is associated with each of pieces of identification information 25_1 to 25_n. When receiving the status information after transmitting a beacon signal, the communication apparatus selects, based on the status information, another identification information different from identification information of the beacon signal transmitted most recently and transmits a beacon signal including the selected identification information, instead of the beacon signal transmitted most recently.

Abstract: The invention provides a grease composition for lubrication of a sliding surface made of resin, including a fluorine-based base oil and a synthetic hydrocarbon oil as a base oil; a fluorine-based thickener, and a lithium soap thickener or a lithium complex soap thickener as a thickener; and an extreme pressure additive as an additive. The invention also provides a sliding member including a sliding surface made of a resin wherein the grease composition for lubrication is applied to the sliding surface made of a resin.

Abstract: The invention provides a grease composition for lubrication of a sliding surface made of resin, including a fluorine-based base oil and a synthetic hydrocarbon oil as a base oil; a fluorine-based thickener, and a lithium soap thickener or a lithium complex soap thickener as a thickener; and an extreme pressure additive as an additive. The invention also provides a sliding member including a sliding surface made of a resin wherein the grease composition for lubrication is applied to the sliding surface made of a resin.

Abstract: There is provided a bolt sensor which detects a fastened state of a bolt. The bolt sensor includes a sensor body including a through hole into which a shaft of the bolt is to be inserted, a light guide extending along an outer periphery of the sensor body, and a light source configured to emit light to the light guide based on output of the sensor body.

Abstract: There is provided a bolt sensor which detects a fastened state of a bolt. The bolt sensor includes a sensor body including a through hole into which a shaft of the bolt is to be inserted, a light guide extending along an outer periphery of the sensor body, and a light source configured to emit light to the light guide based on output of the sensor body.