US 12,394,439 B2
Hard disk drive including annular spacer with inclined region on main surface
Masao Takano, Akishima (JP)
Assigned to HOYA CORPORATION, Tokyo (JP)
Filed by HOYA CORPORATION, Tokyo (JP)
Filed on Jun. 26, 2024, as Appl. No. 18/754,466.
Application 18/754,466 is a continuation of application No. 18/029,251, granted, now 12,051,442, previously published as PCT/JP2021/036234, filed on Sep. 30, 2021.
Claims priority of provisional application 63/085,262, filed on Sep. 30, 2020.
Prior Publication US 2024/0347076 A1, Oct. 17, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. G11B 17/038 (2006.01); G11B 25/04 (2006.01)
CPC G11B 17/038 (2013.01) [G11B 25/043 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A hard disk drive comprising:
a magnetic disk; and
an annular spacer including
two main surfaces,
an inner circumferential surface,
an outer circumferential surface, and
a chamfered surface present between the outer circumferential surface and each of the two main surfaces,
the annular spacer being disposed such that one of the two main surfaces is in contact with the magnetic disk, wherein
at least one main surface of the two main surfaces includes an inclined region, and the inclined region is inclined in an outer circumferential region of the at least one main surface toward a boundary between the at least one main surface and the chamfered surface such that a surface height of the spacer gradually decreases toward the boundary,
the magnetic disk has a thickness of 0.55 mm or less, and
a material of a substrate for the magnetic disk includes aluminum alloy.