| 摘要 |
PURPOSE:To position a head to the initial position of the single plate of a magnetic disc by one device independently of size, by providing several load points in moire. CONSTITUTION:Windows A-C of a moire 1 through which the light is transmitted are provided in positions corresponding to initial positions (loading points) of magnetic disc single plates of respective sizes, and the transmitted light is incident to a light receiving part 5. A lattice part 9 has the shape of a lattice for the seek control. The light from the loading point of each of windows A-C is converted to pulses, and they are transmitted to a controlling up/down counter 15, and the counter 15 is set or reset for carry or borrow by an FF16 to detect that the magnetic disc single plate of the size reaches the initial position. When carry is generated, the head falls softly to complete head loading. When borrow is generated to reset the FF16, it is indicated that the head is off the initial position on the magnetic disc single plate, and the head is moved forward again and seeks the initial position again. |
