Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Extended-Arm Rotary Actuator for Magnetic Recording Disk Drive

IP.com Disclosure Number: IPCOM000036876D
Original Publication Date: 1989-Nov-01
Included in the Prior Art Database: 2005-Jan-29
Document File: 3 page(s) / 36K

Publishing Venue

IBM

Related People

Sohn, WJ: AUTHOR

Abstract

Disclosed is an extended-arm rotary actuator which has a minimized skew-angle variation and a minimized angle of rotation for a complete stroke. This actuator is therefore compatible with sliders and recording heads used in magnetic recording disk drives which prefer low skew angles. Furthermore, the reduced angle of rotation of the arm partially compensates for the increased moment of inertia so that low access times can be achieved. The minimized angle of rotation allows for the design of a more compact voice coil motor which facilitates the design of disk drives with high volumetric density.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 83% of the total text.

Page 1 of 3

Extended-Arm Rotary Actuator for Magnetic Recording Disk Drive

Disclosed is an extended-arm rotary actuator which has a minimized skew- angle variation and a minimized angle of rotation for a complete stroke. This actuator is therefore compatible with sliders and recording heads used in magnetic recording disk drives which prefer low skew angles. Furthermore, the reduced angle of rotation of the arm partially compensates for the increased moment of inertia so that low access times can be achieved. The minimized angle of rotation allows for the design of a more compact voice coil motor which facilitates the design of disk drives with high volumetric density.

Referring to Fig. 1, in order to minimize the skew-angle variation and the full-stroke angle of rotation, the length of the arm must be:

(Image Omitted)

where L = Distance from recording head to arm pivot. R = Distance from arm pivot to center of disk.

rID = Inner data radius.

rOD = Outer data radius.

(Image Omitted)

The total variation of the skew angle for the extended arm is given by:

(Image Omitted)

where

(Image Omitted)

The median value of the skew angle is dependent on the angle between the recording head and the arm and is given by:

(Image Omitted)

where

(Image Omitted)

g = Angle between the perpendicular bisector

of the recording head and a line from the

pivot

of the arm to the center of the recording

head.

Typically, using an extended-arm instead of a standard length arm reduces the skew-angle variati...