Western Digital Corporation

Western Digital Technologies, Inc.

Lance A Gabrielson

Peter E Brooks

A disk drive is usable in a chassis having first and second guide channels mounted on side surfaces of the chassis. The disk drive includes a head disk assembly that includes first and second side walls. The disk drive further includes first and second side rails and a securing system for securing the side rails to the side walls. The first and second side rails engage the first and second guide channels, respectively, for supporting the disk drive within the chassis. The securing system includes an engagement mechanism and a double-sided adhesive resilient mechanism. The engagement mechanism projects between the first and second side rails and the first and second side walls, respectively, of the head disk assembly. The double-sided adhesive resilient mechanism is adhesively attached between the first side rail and the first side wall and between the second side rail and the second side wall for mounting the first and second side rails to the first and second side walls, respectively, of the head disk assembly. The securing system provides for relative movement between the side rails and the side walls to accommodate the side rails engaging the guide channels in the chassis. In one embodiment, the relative movement is a damped relative movement.

Disk drive including resilient securing system providing relative movement between side rails and head disk assembly to accommodate side rails engaging guide channels in a chassis

A method of centering a disk pack on a base rotatably supporting the disk pack includes performing a series a steps while the disk pack is rotating. A reference timing signal is generated. A first imbalance in the rotating disk pack is detected, and a first imbalance signal is produced. The first imbalance signal is correlated with the reference timing signal to produce a first correlation value, which indicates a location of the first imbalance relative to the reference timing signal. Based upon the first correlation value, a first impact is applied to the base, causing the base to shift relative to the disk pack. As a result of the first impact, the first imbalance moves to a second imbalance. The second imbalance is detected, and a second imbalance signal is produced. The second imbalance signal is correlated with the reference timing signal to produce a second correlation value, which indicates a location of the second imbalance relative to the reference timing signal. A phase compensation value is also determined, based upon the first and second correlation values. The phase compensation value indicates a phase difference between an actual location of the first imbalance and a desired location of the first imbalance when the first impact was applied. Based upon the phase compensation value, a second impact is applied to the base, again causing the base to shift relative to the disk pack.

Method of centering a disk pack of a disk drive

A system for balancing devices having motors and rotating masses to be coupled to the motors utilizes a momentum transfer mechanism to shift the rotating mass based on sensed imbalance. In this manner the mass is shifted to a position which accounts for the inherent imbalance in both the motor and the mass. A controller receives imbalance information from a velocity sensor and controls a solenoid to strike a base coupled to the motor to shift a lightly clamped mass relative to the motor. In one embodiment, a disk drive has disks initially biased by the system against a hub, and then shifted during rotation to create a disk drive having concentrically aligned disks offsetting imbalance inherent in a motor used to rotate the disks. In one embodiment, the disks are held to the hub by a clamp having screws. The screws are driven simultaneously through the same angle of rotation to ensure that the axial clamping force of each one is substantially equal. In a further embodiment, the screws are formed of a heat shrink material, and shrunk following initial light tightening to provide consistent axial clamping force.

Growing community of inventors

Rochester, MN, United States of America

Lance A Gabrielson