Hoya Assigned Five Patents

Spacer and hard disk drive
Hoya Corporation, Tokyo, Japan, has been assigned a patent (10,872,635) developed by Takano, Masao, Akishima, Japan, for “spacer and hard disk drive apparatus.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”When removing magnetic disks and spacers from a hard disk drive apparatus, as necessary, during the assembly of the hard disk drive apparatus, in order to suppress the occurrence of removal failures when removing the spacers using a gripping jig, a surface roughness Rz of an outer circumferential edge surface of a spacer is set to be at least 1.5 .mu.m.”

The patent application was filed on August 31, 2018 (16/634,079).

Glass spacer and HDD
Hoya Corporation, Tokyo, Japan, has been assigned a patent (10,783,921) developed by Takano, Masao, Akishima, Japa, and Eda, Shinji, Hung Yen Province, VietNam, for “glass spacer and hard disk drive apparatus.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”In order to suppress the occurrence of adhesion between magnetic disks and spacers when the magnetic disks and the spacers are removed from a hard disk drive apparatus in which the magnetic disks and the spacers are installed, a surface roughness Ra of a main surface of a ring-shaped glass spacer to be arranged in contact with a magnetic disk is set to be not larger than 1.0 .mu.m, and an average inclination R.DELTA.a of the main surface is set to be at least 0.02.”

The patent application was filed on October 1, 2018 (16/634,128).

Magnetic-disk glass substrate, glass substrate intermediate and manufacturing
Hoya Corporation, Tokyo, Japan, has been assigned a patent (10,720,180) developed by Azuma, Shuhei, Akishima, Japan, for “magnetic-disk glass substrate, magnetic-disk glass substrate intermediate, and method for manufacturing magnetic-disk glass substrate.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic-disk glass substrate containing an alkaline earth metal component as a glass composition includes an edge surface that is a mirror surface, and has a roughness percentage of 40% or more when a bearing ratio of a roughness cross-sectional area is 50% in a bearing ratio curve of roughness cross-sectional areas obtained when a surface roughness of the edge surface obtained after the edge surface is etched by 2.5 .mu.m is measured.”

The patent application was filed on September 30, 2016 (15/579,033).

Magnetic disk substrate with specified changes in height or depth between adjacent raised or lowered portions and offset portion on main surface
Hoya Corporation, Tokyo, Japan, has been assigned a patent (10,607,647) developed by Takizawa, Toshio, Tokyo, Japan, Phandon, Kraisorn, Lamphun, Thailand, and Nishimori, Kenichi, Tokyo, Japan, for “magnetic disk substrate with specified changes in height or depth between adjacent raised or lowered portions and an offset portion on a main surface within a range of 92.0 to 97.0% in a radial direction from a center, a magnetic disk with substrate and magnetic disk device.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”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.’”

The patent application was filed on June 1, 2017 (15/611,243).

Magnetic-disk glass substrate, magnetic disk and manufacturing
Hoya Corporation, Tokyo, Japan, has been assigned a patent (10,580,448) developed by Ueda, Masaaki, Yokohama, Japan, for “magnetic-disk glass substrate, magnetic disk and method for manufacturing magnetic-disk glass substrate.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic-disk glass substrate of the present invention includes a pair of main surfaces, a side wall surface, and a chamfered surface between the main surfaces and the side wall surface. Regarding surface properties of at least one of the side wall surface and the chamfered surface of the glass substrate, an arithmetic average roughness, (Ra) is 0.015 .mu.m or less, and a bearing factor of a roughness cross-sectional area when a roughness percentage is 60% is 95% or more in a bearing curve of a roughness cross-sectional area.’”

The patent application was filed on May 30, 2017 (15/608,346).