Enlarged substrate for magnetic recording medium

Patent metadata

Field	Value
Publication number	US-9799364-B2
Application number	US-201715595514-A
Country	US
Kind code	B2
Filing date	May 15, 2017
Priority date	May 16, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

An enlarged substrate configuration for magnetic recording media. In some embodiments, an apparatus comprises a disc shaped member of metal or glass configured as a substrate for a magnetic data recording disc for a 2½ inch form factor data storage device or a 3½ inch form factor data storage device. The disc shaped member has a top planar surface, an opposing bottom planar surface, an outermost annular sidewall that extends between the top planar surface and the bottom planar surface at an outermost diameter of nominally 67 or 97 millimeters, respectively, and an inner annular sidewall that extends between the top planar surface and the bottom planar surface to define a central aperture.

First claim

What is claimed is:

1. An apparatus comprising a disc shaped member of metal or glass configured as a substrate for a magnetic data recording disc for a 3½ inch form factor data storage device, the disc shaped member having a top planar surface, an opposing bottom planar surface, an outermost annular sidewall that extends between the top planar surface and the bottom planar surface at an outermost diameter of nominally 97 millimeters, mm, and an inner annular sidewall that extends between the top planar surface and the bottom planar surface to define a central aperture.

2. The apparatus of claim 1 , wherein the inner annular sidewall extends at an innermost diameter of nominally 25 mm.

3. The apparatus of claim 1 , wherein the disc shaped member further has an upper chamfered surface that annularly extends between the top planar surface and the inner annular sidewall at a selected angle non-orthogonal to the top planar surface.

4. The apparatus of claim 3 , wherein the selected angle is nominally 45 degrees with respect to the top planar surface.

5. The apparatus of claim 3 , wherein the selected angle is nominally 25 degrees with respect to the top planar surface.

6. The apparatus of claim 3 , wherein the disc shaped member further has a lower chamfered surface that annularly extends between the bottom planar surface and the inner annular sidewall at the selected angle.

7. The apparatus of claim 6 , wherein the upper chamfered surface is an inner upper chamfered surface and the lower chamfered surface is an inner lower chamfered surface, and wherein the disc shaped member further has an outer upper chamfered surface that annularly extends between the top planar surface and the outer annular sidewall at a second selected angle non-orthogonal to the top planar surface and an outer lower chamfered surface that annularly extends between the bottom planar surface and the outer annular sidewall at the second selected angle.

8. The apparatus of claim 1 , wherein the disc shaped member further comprises an upper annular relief zone that curvilinearly transitions between the top planar surface and the outermost annular sidewall, and a lower annular relief zone that curvilinearly transitions between the bottom planar surface and the outermost annular sidewall.

9. The apparatus of claim 1 , wherein at least one of the upper annular relief zone or the lower annular relief zone is characterized as a duboff (DO) zone.

10. The apparatus of claim 8 , wherein at least one of the upper annular relief zone or the lower annular relief zone is characterized as a ski jump (SJ) zone.

11. An apparatus comprising a disc shaped member of metal or glass configured as a substrate for a magnetic data recording disc for a 2½ inch form factor data storage device, the disc shaped member having a top planar surface, an opposing bottom planar surface, an outermost annular sidewall that extends between the top planar surface and the bottom planar surface at an outermost diameter of nominally 67 millimeters, mm, and an inner annular sidewall that extends between the top planar surface and the bottom planar surface to define a central aperture.

12. The apparatus of claim 11 , wherein the inner annular sidewall extends at an innermost diameter of nominally 25 mm.

13. The apparatus of claim 11 , wherein the disc shaped member further has an upper chamfered surface that annularly extends between the top planar surface and the inner annular sidewall at a selected angle non-orthogonal to the top planar surface.

14. The apparatus of claim 13 , wherein the selected angle is nominally 45 degrees with respect to the top planar surface.

15. The apparatus of claim 13 , wherein the selected angle is nominally 25 degrees with respect to the top planar surface.

16. The apparatus of claim 13 , wherein the disc shaped member further has a lower chamfered surface that annularly extends between the bottom planar surface and the inner annular sidewall at the selected angle.

17. The apparatus of claim 16 , wherein the upper chamfered surface is an inner upper chamfered surface and the lower chamfered surface is an inner lower chamfered surface, and wherein the disc shaped member further has an outer upper chamfered surface that annularly extends between the top planar surface and the outer annular sidewall at a second selected angle non-orthogonal to the top planar surface and an outer lower chamfered surface that annularly extends between the bottom planar surface and the outer annular sidewall at the second selected angle.

18. The apparatus of claim 11 , wherein the disc shaped member further comprises an upper annular relief zone that curvilinearly transitions between the top planar surface and the outermost annular sidewall, and a lower annular relief zone that curvilinearly transitions between the bottom planar surface and the outermost annular sidewall.

19. The apparatus of claim 11 , wherein at least one of the upper annular relief zone or the lower annular relief zone is characterized as a duboff (DO) zone.

20. The apparatus of claim 18 , wherein at least one of the upper annular relief zone or the lower annular relief zone is characterized as a ski jump (SJ) zone.

Assignees

• Seagate Technology Llc

Inventors

• Adachi Koji
• Beresford Ian J
• Chang Thomas Y
• Hwang Kuo Hsing
• Hennessy James
• Perez David

Classifications

• G11B19/28

  Speed controlling, regulating, or indicating (G11B19/24 takes precedence) · CPC title

• G11B5/82 Primary

  Disk carriers · CPC title

• G11B5/5526

  Control therefor; circuits, track configurations or relative disposition of servo-information transducers and servo-information tracks for control thereof (G11B5/556 takes precedence) · CPC title

• G11B5/39

  using magneto-resistive devices {or effects} · CPC title

• G11B2020/1238

  track, i.e. the entire a spirally or concentrically arranged path on which the recording marks are located · CPC title