| 摘要 |
<p>PURPOSE:To obtain stable contact between a magnetic head and a magnetic tape over the whole range around a cylinder by changing the position of a tape guide member over against the outer circumferential surface of the rotary cylinder in accordance with a signal of a position detecting means. CONSTITUTION:A position detecting sensor is composed of a magnet 12 and an MR element 13, and the magnet 12 if fitted to the rotary cylinder 1, while the MR element 13 is fitted opposite to the magnet 12 to a stationary cylinder 16. The stationary cylinder 16 is provided with a tape guide for guiding the magnetic tape 11. An output obtained from the MR element 13 is changed when the magnet 12 approaches the MR element 13, so that the rotary position of the rotary cylinder at that time can be detected. Then, the tape guide member is controlled to be changed in its position over against the outer circumferential surface of the rotary cylinder in accordance with an output signal of the position detecting sensor. By this method, the magnetic tape on its inlet side where the magnetic tape floating amt. is large is pulled to a magnetic head window part, so that the stable contact between the magnetic head and the magnetic tape can be obtained.</p> |
