Abstract: An improved structure of a spindle motor for use in a floppy disk device is provided. The spindle motor includes a stator and a radial bearing. The stator is made of a magnetic metal plate on which an electric circuit is provided and in which a bearing mount hole is formed. The radial bearing supports a spindle and includes a mounting outer wall fitted within the bearing mount hole of the stator and a bearing wall taking a radial load acting on the spindle. A groove is formed in the radial bearing between the mounting outer wall and the bearing wall to absorb the stress produced upon installation of the radial bearing which may cause the bearing wall to be deformed undesirably.

Abstract: In a magnetic recording and reproducing apparatus having a signal multiplexer circuit and a signal demultiplexer circuit disposed on each of a plurality of circuit boards, including a record/reproduce control circuit board and a motor circuit board, connected to each other by a cable, the signal multiplexer circuit located on the circuit board generating a plurality of signals to be transmitted multiplexes these signals to form a multiplexed signal to be supplied to the other circuit board through the cable, and the corresponding signal demultiplexer circuit located on the other circuit board restores the multiplexed signal into the individual signals, so that the number of signal conductors in the cable interconnecting the plural circuit boards can be decreased, thereby improving the reliability of the connection and reducing the size of the connection.