Information recording apparatus

• US 20070223132A1
• Filed: 03/20/2007
• Published: 09/27/2007
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: HGST Netherlands B.V. (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Tsuchinaga, Hiroyuki
• Granted Patent: US 7,417,821 B2
• Time in Patent Office: Days
• US Class Current: 360/75
• CPC Class Codes: G11B 20/1258 where blocks are arranged within multiple radial zones, e.g. Zone Bit Recording or Constant Density Recording discs, MCAV discs, MCLV discs
• CPC Class Codes: G11B 2020/1238 track, i.e. the entire a spirally or concentrically arranged path on which the recording marks are located
• CPC Class Codes: G11B 2020/1242 the area forming one or more zones, wherein each zone is shaped like an annulus or a circular sector
• CPC Class Codes: G11B 2020/1267 Address data
• CPC Class Codes: G11B 2020/1288 Formatting by padding empty spaces with dummy data, e.g. writing zeroes or random data when de-icing optical discs
• CPC Class Codes: G11B 2220/2516 Hard disks
• CPC Class Codes: G11B 27/24 by sensing features on the record carrier other than the transducing track ; sensing signals or marks recorded by another method than the main recording
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence

Abstract

According to embodiments of the present invention, tracks can be formed on a magnetic recording medium on a zonal area at intervals of either a first track pitch or a second track pitch, both of which differ from each other. For an reference track defined in each zonal area, regardless of whether tracks are formed with the first track pitch or the second track pitch, the first track pitch and the second track pitch are specified so that a head position at the time of writing or reading information to or from the reference track, is common to both of the first track pitch and the second track pitch.

Claims

1. An information recording apparatus, comprising:

a magnetic recording medium;

a head for writing/reading information to/from the magnetic recording medium;

a storage unit; and

a controller;

wherein tracks are formed on the magnetic recording medium, said tracks being formed on a zonal area at intervals of either a first track pitch or a second track pitch, both of which differ from each other, and, for an reference track defined in said each zonal area, regardless of whether tracks are formed with the first track pitch or the second track pitch in said each zonal area, the first track pitch and the second track pitch are specified so that a position of the head at the time of writing or reading information to or from the reference track is common to the first track pitch and the second track pitch;

wherein said storage unit stores a table that specifies a position of the head at the time of writing information to an reference track of each zonal area in which tracks are formed with the first track pitch, and a position of the head at the time of reading information from an reference track of each zonal area in which tracks are formed with the first track pitch; and

wherein if a track, which is specified as a target track to or from which information is written or read, is included in a zonal area in which tracks are formed with the second track pitch, said controller determines, through arithmetic operation, a position of the head at the time of writing or reading information to or from the specified track on the basis of information stored in said table.

2. The information recording apparatus according to claim 1, wherein:

said second track pitch is the track pitch with which an attention track is partially overwritten by a track adjacent to the attention track;

said controller generates said table on the basis of the tracks formed with the first track pitch;

erases part of the reference track among the tracks formed with the first track pitch to form each track having the same width as that of the tracks formed with the second track pitch;

determines a position of the head at the time of reading information from each track having the same width as that of the tracks formed with the second track pitch; and

then stores the positions in the storage unit as an offset table; and

if a track, which is specified as a target track from which information is read, is included in a zonal area in which tracks are formed with the second track pitch, the controller uses the offset table to determine a position of the head.