公开(公告)号：US20170270956A1

公开(公告)日：2017-09-21

申请号：US15611243

申请日：2017-06-01

Applicant: HOYA CORPORATION ,  HOYA GLASS DISK (Thailand) LTD.

Inventor： Toshio TAKIZAWA ,  Kraisorn PHANDON ,  Kenichi NISHIMORI

IPC: G11B5/73 ,  G11B5/82

CPC classification number: G11B5/7315 ,  G11B5/82

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.”

公开(公告)号：US20150109703A1

公开(公告)日：2015-04-23

申请号：US14551675

申请日：2014-11-24

Applicant: HOYA CORPORATION ,  HOYA GLASS DISK (Thailand) LTD.

Inventor： Toshio TAKIZAWA ,  Kraisorn PHANDON ,  Kenichi NISHIMORE

IPC: G11B5/82

CPC classification number: G11B5/7315 ,  G11B5/82

Abstract: A magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of the magnetic disk substrate is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.

Abstract translation: 即使磁盘高速旋转也适用于通过加载/卸载方法启动和停止的硬盘以及使用这种基板的磁盘，高度可靠地防止发生碰撞故障的磁盘基板。 磁盘基板的代表性结构是具有大致平坦的主表面11，端面12，形成在主表面11和端面12之间的倒角面13和偏移部分的圆盘形玻璃基板10， 在主表面11的周边处，相对于主表面11的外周面的平坦表面升高或降低，其特征在于，偏移部分的大小在玻璃的整个圆周上大致均匀 基板10。

公开(公告)号：US20150340054A1

公开(公告)日：2015-11-26

申请号：US14818796

申请日：2015-08-05

Applicant: HOYA CORPORATION ,  HOYA GLASS DISK (Thailand) LTD.

Inventor： Toshio TAKIZAWA ,  Kraisorn PHANDON ,  Kenichi NISHIMORI

IPC: G11B5/73 ,  G11B5/82

CPC classification number: G11B5/7315 ,  G11B5/82

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.”

Abstract translation: 一种磁盘基板，其具有平坦的主表面，端面和形成在主表面和端面之间的倒角面。 该基板具有偏离部分，该主体表面在距离基板中心的径向方向上在92.0至97.0％的范围内。 从基板的中心到基板的端面的径向方向的距离为100％，偏移部相对于连接主面上的两点的虚拟直线上升或下降，设定在92.0的位置 ％和97.0％。 在与虚拟直线垂直的方向上从虚拟直线到偏移部分的最大距离为“最大偏移值”。