| 摘要 |
A tape recorder which comprises; a capstan for driving a magnetic recording tape at a normal constant speed; a first motor for rotating the capstan, including a first rotor magnet, a first rotating shaft mounted to the first rotor magnet and the capstan coaxially, and a first stator coil for applying a rotating magnetic field to the first rotor magnet; a first reel for taking up the tape; a second motor for rotating the first reel, including a second rotor magnet, a second rotating shaft mounted to the second rotor magnet and the first reel coaxially, and a second stator coil for applying a rotating magnetic field to the second rotor magnet; a second reel for supplying the tape; a third motor for rotating the second reel, including a third rotor magnet, a third rotating shaft mounted to the third rotor magnet and the second reel coaxially, and a third stator coil for applying a rotating magnetic field to the third rotor magnet; an FG pattern for producing a signal which has a frequency in accordance with a rotational frequency of the first rotor magnet; an output mechanism for producing a signal which has a reference frequency; and a comparator for comparating outputs from the FG pattern and the output mechanism and for controlling to drive the first motor at a predetermined rotational frequency. |
