In order to suppress the occurrence of adhesion between magnetic disks and spacers when the magnetic disks and the spacers are removed from a hard disk drive apparatus in which the magnetic disks and the spacers are installed, a surface roughness Ra of a main surface of a ring-shaped glass spacer to be arranged in contact with a magnetic disk is set to be not larger than 1.0 m, and an average inclination Ra of the main surface is set to be at least 0.02.

A method for manufacturing a ring-shaped glass spacer to be arranged in contact with a magnetic disk in a hard disk drive device includes processing for forming a film on the surface of a glass spacer main body, which is the base of the glass spacer. In the processing, the film is formed by passing the glass spacer main body through a location where the components of the film are in a spray state while an outer circumferential edge surface of the glass spacer main body is being rotated in a circumferential direction thereof.

In order to suppress the occurrence of adhesion between magnetic disks and spacers when the magnetic disks and the spacers are removed from a hard disk drive apparatus in which the magnetic disks and the spacers are installed, a surface roughness Ra of a main surface of a ring-shaped glass spacer to be arranged in contact with a magnetic disk is set to be not larger than 1.0 m, and an average inclination Ra of the main surface is set to be at least 0.02.

In order to suppress the occurrence of adhesion between magnetic disks and spacers when the magnetic disks and the spacers are removed from a hard disk drive apparatus in which the magnetic disks and the spacers are installed, a surface roughness Ra of a main surface of a ring-shaped glass spacer to be arranged in contact with a magnetic disk is set to be not larger than 1.0 m, and an average inclination Ra of the main surface is set to be at least 0.02.

A ring-shaped glass spacer is to be arranged in contact with a magnetic disk in a hard disk drive device. A film that contains at least one of tin oxide, zinc oxide, and titanium oxide is formed on each surface of a main surface, and an outer circumferential edge surface, and an inner circumferential edge surface of the glass spacer. The thickness of the film on a center portion of the outer circumferential edge surface of the glass spacer is larger than the thickness of the film on a center portion of the inner circumferential edge surface of the glass spacer.

Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position heads proximate to a recording medium of the disks; a spindle motor configured for rotating the one or more disks; and one or more processing devices comprising a servo control processor. The servo control processor is configured to receive a spindle speed error signal indicative of an error in a rotational speed of the spindle motor. The servo control processor is further configured to output an initial frequency offset signal, wherein the initial frequency offset signal is proportional to the spindle speed error signal.

Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position heads proximate to a recording medium of the disks; a spindle motor configured for rotating the one or more disks; and one or more processing devices comprising a servo control processor. The servo control processor is configured to receive a spindle speed error signal indicative of an error in a rotational speed of the spindle motor. The servo control processor is further configured to output an initial frequency offset signal, wherein the initial frequency offset signal is proportional to the spindle speed error signal.

Example alignment members are provided herein. In one example, the alignment member includes a frame member, a stiffener member, a bracket member, and a spring member. The frame member includes a set of roller bushings. The stiffener member includes a set of cam members. The bracket member to receive the stiffener member. The spring member is connected to the stiffener member. The spring member to expand and contract based on the position of the set of roller bushings.

A disk drive assembly including a spindle motor including a hub and a central axis, at least one disk disk having a central opening positioned on the hub and concentric about the central axis, an annular ring member concentric about the central axis, wherein a first portion of the annular ring member is in contact with an outer surface of a top disk of the disk stack, and a disk clamp ring screw adjacent to and in contact with a second portion of the annular ring member, wherein the disk clamp ring screw provides a clamping force to at least partially compress the annular ring member toward the top disk of the disk stack.

A disk drive assembly including a spindle motor including a hub and a central axis, at least one disk disk having a central opening positioned on the hub and concentric about the central axis, an annular ring member concentric about the central axis, wherein a first portion of the annular ring member is in contact with an outer surface of a top disk of the disk stack, and a disk clamp ring screw adjacent to and in contact with a second portion of the annular ring member, wherein the disk clamp ring screw provides a clamping force to at least partially compress the annular ring member toward the top disk of the disk stack.