| 摘要 |
PURPOSE:To use effectively a disc reproducing face at its maximum by fitting plural magnetic heads to the tip of a movable arm, which rotates with the fulcrum as the center, with differenct rotation radiuses from the fulcrum so that the track density of respective reproducing areas on the magnetic disc dependent upon magnetic heads may be different from one another. CONSTITUTION:Two magnetic heads 2 and 3 are fitted to the tip of movable arm 1, which rotates with fulcrum C as the center, so that they may correspond to inside data zone a and outside data zone b of magnetic disc 4 respectively. The relation between rotation radiuses r1 and r2 of magnetic heads 2 and 3 is r1>r2, and movement distances of magnetic heads 2 and 3 are l1 and l2 respectively, and l1/l2 =r1/r2is true. The track density is T/l2>T/l1 when the number of tracks is denoted as T, and the track density of the outside zone is higher. Thus, the recording and reproducing face can be used effectively at its maximum, and the hole of the memory capacity is increased. |
