MAGNETIC-DISK GLASS SUBSTRATE AND MAGNETIC DISK

    公开(公告)号:US20170194025A1

    公开(公告)日:2017-07-06

    申请号:US15467492

    申请日:2017-03-23

    申请人: HOYA CORPORATION

    IPC分类号: G11B5/73

    摘要: A magnetic-disk glass substrate according to the present invention is a doughnut-shaped magnetic-disk glass substrate having a circular hole provided in the center, a pair of main surfaces, and an outer circumferential end surface and an inner circumferential end surface each including a side wall surface and a chamfered surface that is formed between each main surface and the side wall surface. A measurement point is provided on the outer circumferential end surface every 30 degrees in the circumferential direction with reference to a center of the glass substrate, and when a curvature radius of a shape of a portion between the side wall surface and the chamfered surface is determined at each measurement point, the difference in the curvature radius between neighboring measurement points is 0.01 mm or less.

    Dual Circuit Isolation of Writer to Reader Crosstalk for SGV Modules

    公开(公告)号:US20240312482A1

    公开(公告)日:2024-09-19

    申请号:US18227510

    申请日:2023-07-28

    IPC分类号: G11B5/02 G11B5/11 G11B5/73

    摘要: The present disclosure generally relates to a tape head and a tape head drive including a tape head. The tape head comprises at least one same gap verify (SGV) module comprising a plurality of write transducer and read transducer pairs. Each write transducer is coupled to writer bonding pads via writer leads, and each read transducer is coupled to reading bonding pads via reader leads. An isolation shield is disposed between the write transducer and read transducer such that the isolation shield is disposed between each writer lead and each reader lead. The isolation shield acts as a Faraday cage to reduce cross-talk between the write and read transducers. The SGV module is configured to write data to a tape using the write transducers and read verify the data written on the tape using the read transducers such that the write transducers and read transducers are concurrently operable.

    Dual circuit isolation of writer to reader crosstalk for SGV modules

    公开(公告)号:US12094496B1

    公开(公告)日:2024-09-17

    申请号:US18227510

    申请日:2023-07-28

    摘要: The present disclosure generally relates to a tape head and a tape head drive including a tape head. The tape head comprises at least one same gap verify (SGV) module comprising a plurality of write transducer and read transducer pairs. Each write transducer is coupled to writer bonding pads via writer leads, and each read transducer is coupled to reading bonding pads via reader leads. An isolation shield is disposed between the write transducer and read transducer such that the isolation shield is disposed between each writer lead and each reader lead. The isolation shield acts as a Faraday cage to reduce cross-talk between the write and read transducers. The SGV module is configured to write data to a tape using the write transducers and read verify the data written on the tape using the read transducers such that the write transducers and read transducers are concurrently operable.

    Magnetic tape device comprising a characteristic magnetic head and a characteristic medium

    公开(公告)号:US12087337B2

    公开(公告)日:2024-09-10

    申请号:US17872651

    申请日:2022-07-25

    发明人: Norihito Kasada

    摘要: A magnetic tape device. The angle θ formed by the axis of the element array of the magnetic head with respect to a width direction of the magnetic tape is changed during running of the magnetic tape in the magnetic tape device. In a case where a maximum value of an absolute value of a difference between a servo band spacing obtained before storage in a predetermined environment and a servo band spacing obtained after storage in the environment for a storage time T is defined as A, and T is set to a plurality of predetermined times, a medium life calculated by a linear function of A and a logarithm loge T of T, that are derived from a value of A and a value of the logarithm loge T of T obtained for each T is 5 years or longer.

    Substrate for magnetic disk, magnetic disk, and hard disk drive apparatus

    公开(公告)号:US11694718B2

    公开(公告)日:2023-07-04

    申请号:US17472567

    申请日:2021-09-10

    申请人: HOYA CORPORATION

    发明人: Kinobu Osakabe

    IPC分类号: G11B5/73

    摘要: A substrate for a magnetic disk includes a substrate main body having two main surfaces and an outer circumferential edge surface that has a side wall surface and chamfered surfaces, and a film that is an alloy film containing Ni and P and provided on a surface of the substrate main body. A disk shape of the substrate main body has an outer diameter of 90 mm or more. A thickness T of the substrate that includes the film provided on the main surfaces is 0.520 mm or less. A total thickness D mm of the film on the main surfaces and the thickness T mm satisfy D≥0.0082/T−0.0015. A film thickness of the film on the outer circumferential edge surface is larger than a film thickness of the film on the main surfaces, and is 150% or less of the film thickness of the film on the main surfaces.

    SUBSTRATE FOR MAGNETIC DISK, MAGNETIC DISK, AND HARD DISK DRIVE APPARATUS

    公开(公告)号:US20230298623A1

    公开(公告)日:2023-09-21

    申请号:US18321166

    申请日:2023-05-22

    申请人: HOYA CORPORATION

    发明人: Kinobu OSAKABE

    IPC分类号: G11B5/73

    摘要: A substrate for a magnetic disk includes a substrate main body having two main surfaces and an outer circumferential edge surface, and a film that is an alloy film containing Ni and P and provided on a surface of the substrate main body. A disk shape of the substrate main body has an outer diameter of 90 mm or more. A thickness T of the substrate that includes film thicknesses of sections of the film provided on the main surfaces is 0.520 mm or less. A total thickness D mm, which is a sum of the film thicknesses of the sections of the film on the main surfaces and the thickness T mm satisfy D≥0.0082/T−0.0015. A surface roughness maximum height Rz of the film provided on the outer circumferential edge surface is smaller than that of the substrate main body at the outer circumferential edge surface.

    Magnetic tape device
    8.
    发明授权

    公开(公告)号:US11735213B2

    公开(公告)日:2023-08-22

    申请号:US17872566

    申请日:2022-07-25

    IPC分类号: G11B5/592 G11B5/73 G11B5/008

    摘要: A magnetic tape device. The angle θ formed by the axis of the element array of the magnetic head with respect to a width direction of the magnetic tape is changed during running of the magnetic tape in the magnetic tape device. The magnetic tape satisfies Equation 1: TDSage+TDSenv−TC≤0.10 μm. In Equation 1, the TDSage is a maximum value of an absolute value of a difference between a servo band spacing obtained before storage for 24 hours in a predetermined environment and a servo band spacing obtained after the storage. TDSenv is a value calculated by multiplying a difference between a maximum value and a minimum value of servo band spacings obtained in each of five predetermined environments by ½, and TC is a value calculated by TC=L{cos (θinitial−Δθ)−cos (θinitial+Δθ)}.