Abstract: In an information storage apparatus, a relatively thin attachment member has a cylindrical boss section projecting from a surface thereof and a path passing through the attachment member and reaching the extreme end of the boss section and is attached to a relatively thick base member. The base member has a through hole which passes therethrough in the thickness direction thereof and into which the boss section is inserted. The attachment member is caulked to the base member by plastically deforming the boss section by causing a caulking ball whose diameter is larger than that of the path to pass therethrough in the state that the boss section is inserted into the through hole. The through hole has an escape section into which a part of the plastically deformed boss section escapes, thereby a large amount of plastic deformation of the boss section can be suppressed.

Abstract: Upon correction, an amplitude measurement unit repeats a process of attaining a write heat state by a write clearance control unit and writing user data to a data region of a measurement track in the state in which a head is positioned to an arbitrary measurement track and then switching the state to a read heat state by a read clearance control unit so as to detect an amplitude of a read signal from a preamble unit in a servo region. A variance calculation unit calculates a variance from the plurality of amplitude measurement values measured by the amplitude measurement unit; and a contact determination unit repeats the measurement process by the amplitude measurement unit while sequentially increasing the base heater control value when the variance is less than a predetermined threshold value and determines contact between the head and the medium when the variance exceeds the threshold value.

Abstract: Upon correction, an amplitude measurement unit repeats a process of attaining a write heat state by a write clearance control unit and writing user data to a data region of a measurement track in the state in which a head is positioned to an arbitrary measurement track and then switching the state to a read heat state by a read clearance control unit so as to detect an amplitude of a read signal from a preamble unit in a servo region. A variance calculation unit calculates a variance from the plurality of amplitude measurement values measured by the amplitude measurement unit; and a contact determination unit repeats the measurement process by the amplitude measurement unit while sequentially increasing the base heater control value when the variance is less than a predetermined threshold value and determines contact between the head and the medium when the variance exceeds the threshold value.

Abstract: A head slider includes a positive pressure generating portion constituting an air bearing surface that is formed at land portions higher than a base surface of a head slider body formed opposite to a storage medium by a predetermined difference in level, and that generates a positive pressure; a head element portion formed in the vicinity of an air flowing-out edge of the slider body for making an access to a recording medium; and expansion portions constituting expansion members that have a higher thermal expansion coefficient than that of a constituent material of land portions and that expand/contract in response to change of environmental temperature.

Abstract: In an information storage apparatus, a relatively thin attachment member has a cylindrical boss section projecting from a surface thereof and a path passing through the attachment member and reaching the extreme end of the boss section and is attached to a relatively thick base member. The base member has a through hole which passes therethrough in the thickness direction thereof and into which the boss section is inserted. The attachment member is caulked to the base member by plastically deforming the boss section by causing a caulking ball whose diameter is larger than that of the path to pass therethrough in the state that the boss section is inserted into the through hole. The through hole has an escape section into which a part of the plastically deformed boss section escapes, thereby a large amount of plastic deformation of the boss section can be suppressed.