Abstract: A base plate is a portion of a housing of a hard disk drive, and includes a cast base body. The base body includes an inner surface including an inside machined surface that is machined and an inside non-machined surface that is not machined. The base body includes an outer surface including an outside machined surface that is machined and an outside non-machined surface that is not machined. The outside machined surface and the inside non-machined surface overlap in an axial direction that is a direction parallel or substantially parallel to a rotation axis of a disk of the hard disk drive.

Abstract: A base plate is a portion of a housing of a hard disk drive, and includes a cast base body. The base body includes an inner surface including an inside machined surface that is machined and an inside non-machined surface that is not machined. The base body includes an outer surface including an outside machined surface that is machined and an outside non-machined surface that is not machined. The outside machined surface and the inside non-machined surface overlap in an axial direction that is a direction parallel or substantially parallel to a rotation axis of a disk of the hard disk drive.

Abstract: A disk drive housing includes an accommodation unit in which a disk and a motor are accommodated, the disk rotating about a center axis extending vertically, the motor rotating the disk; and a non-piercing first screw hole including a die-cast metal in which an upper surface is opened, the non-piercing first screw hole extending from a first end surface toward a second end surface. The first screw hole includes a first region disposed at a leading end of an inner surface of the first screw hole, the first region including a first portion of the die-cast metal member covered with a chill layer; and a second region in which a screw is disposed on an inner circumferential surface of the first screw hole, the second region including a second portion of the die-cast metal member that is exposed.

Abstract: A disk drive housing includes an accommodation unit in which a disk and a motor are accommodated, the disk rotating about a center axis extending vertically, the motor rotating the disk; and a non-piercing first screw hole including a die-cast metal in which an upper surface is opened, the non-piercing first screw hole extending from a first end surface toward a second end surface. The first screw hole includes a first region disposed at a leading end of an inner surface of the first screw hole, the first region including a first portion of the die-cast metal member covered with a chill layer; and a second region in which a screw is disposed on an inner circumferential surface of the first screw hole, the second region including a second portion of the die-cast metal member that is exposed.

Abstract: A base of a disk drive apparatus includes a bottom plate portion, a pivot post, and a recessed portion. A lower surface of the bottom plate portion includes a first lower surface and a second lower surface. The first lower surface is arranged to extend perpendicularly to the first and second axes on a side of the recessed portion on which the first axis lies. The second lower surface is arranged to extend perpendicularly to the first and second axes on an opposite side of the recessed portion with respect to the first axis and at a level higher than that of the first lower surface. The first lower surface includes a projecting portion arranged adjacent to the recessed portion, and arranged to project in a direction away from the first axis.

Abstract: A base of a disk drive apparatus includes a bottom plate portion and a wall portion. The wall portion includes an increased thickness portion and a decreased thickness portion. An inner surface of the increased thickness portion includes a first slanting surface arranged to extend radially outward away from a central axis while extending axially away from the bottom plate portion. An inner surface of the decreased thickness portion includes a second slanting surface arranged to extend radially outward away from the central axis while extending axially away from the bottom plate portion, and protrude radially inward relative to the first slanting surface. An inclination angle of the second slanting surface with respect to an axial direction is arranged to be smaller than an inclination angle of the first slanting surface with respect to the axial direction.

Abstract: A fluid dynamic bearing mechanism includes a stationary shaft, a sleeve portion arranged to rotate with respect to the shaft, and a thrust portion including an upper end surface arranged oppose to a lower end surface of the sleeve portion. An inside surface of the thrust portion includes an inside surface contact portion arranged in contact with an outside surface of the shaft, and an inside surface lower non-contact portion spaced away from the outside surface of the shaft, and arranged to extend downward from a lower end of the inside surface contact portion. An outside surface of the thrust portion includes an outside surface inclined portion arranged in contact with an interface of a lubricating oil. The lower end of the inside surface contact portion is arranged at a level axially higher than that of a lower end of the outside surface inclined portion.

Abstract: A fluid dynamic bearing mechanism includes a stationary shaft, a sleeve portion arranged to rotate with respect to the shaft, and a thrust portion including an upper end surface arranged oppose to a lower end surface of the sleeve portion. An inside surface of the thrust portion includes an inside surface contact portion arranged in contact with an outside surface of the shaft, and an inside surface lower non-contact portion spaced away from the outside surface of the shaft, and arranged to extend downward from a lower end of the inside surface contact portion. An outside surface of the thrust portion includes an outside surface inclined portion arranged in contact with an interface of a lubricating oil. The lower end of the inside surface contact portion is arranged at a level axially higher than that of a lower end of the outside surface inclined portion.

Abstract: In the base bracket of the motor, the bottom-inner surface of the base bracket includes a first bottom-inner area arranged over a circuit board attaching portion of a bottom-outer surface to which the circuit board is attached, and a second bottom-inner area arranged other than the first bottom-inner area in a level axially lower than the first bottom-inner area. The second bottom-inner area defines a base of the concave portion arranged in the bottom-inner surface of the base bracket. A characteristic frequency of the disk storage device using the motor with the base bracket is preferably adjustable by changing the depth or width of the concave portion while the strength of the base bracket is preferably maintained.

Abstract: In the base bracket of the motor, the bottom-inner surface of the base bracket includes a first bottom-inner area arranged over a circuit board attaching portion of a bottom-outer surface to which the circuit board is attached, and a second bottom-inner area arranged other than the first bottom-inner area in a level axially lower than the first bottom-inner area. The second bottom-inner area defines a base of the concave portion arranged in the bottom-inner surface of the base bracket. A characteristic frequency of the disk storage device using the motor with the base bracket is preferably adjustable by changing the depth or width of the concave portion while the strength of the base bracket is preferably maintained.

Abstract: In the base bracket of the motor, the bottom-inner surface of the base bracket includes a first bottom-inner area arranged over a circuit board attaching portion of a bottom-outer surface to which the circuit board is attached, and a second bottom-inner area arranged other than the first bottom-inner area in a level axially lower than the first bottom-inner area. The second bottom-inner area defines a base of the concave portion arranged in the bottom-inner surface of the base bracket. A characteristic frequency of the disk storage device using the motor with the base bracket is preferably adjustable by changing the depth or width of the concave portion while the strength of the base bracket is preferably maintained.

Abstract: In the base bracket of the motor, the bottom-inner surface of the base bracket includes a first bottom-inner area arranged over a circuit board attaching portion of a bottom-outer surface to which the circuit board is attached, and a second bottom-inner area arranged other than the first bottom-inner area in a level axially lower than the first bottom-inner area. The second bottom-inner area defines a base of the concave portion arranged in the bottom-inner surface of the base bracket. A characteristic frequency of the disk storage device using the motor with the base bracket is preferably adjustable by changing the depth or width of the concave portion while the strength of the base bracket is preferably maintained.