| 摘要 |
1516678 Electromagnetic devices; printed circuits INTERNATIONAL BUSINESS MACHINES CORP 20 June 1975 26267/75 Addition to 1342495 Heading H1P and H1R [Also in Division G5] A record/play-back assembly comprises an actuator mechanism for positioning the transducer of disc information storage apparatus having (Fig. 1) a triangular insulant laminar substrate 1 on each face of which planar printed circuit coils 2 are impressed for series connection over through-hole 3. The substrate is movable in its plane on pivot 5 at the apex, and the axes of the coils intersect the pivot. C- shaped permanent magnet structures 6 have narrow gaps 10 of polepieces 8, 9 which embrace the lamina symmetrically of the radial portions of the coils, and an arm 11 is also mounted on the pivot to support a transducer head at its free end. Energization of the coils with current of predetermined sense and magnitude through flexible leads (not shown) produces corresponding movement of the head over a limited arc, e.g. in response to a servo controlled loop supplied with information defining the head position. In a complete information storage apparatus (Fig. 2) a magnetic disc 13 is supported on magnetizable hub 14 in a plastic cartridge 15. carried by a frame (not shown) whereby the disc is rotatable on spindle 16 of motor 17; a magnetic chuck carried by the spindle locking the disc in place. The actuator is mounted so that head 12 projects into an elongated radial slot of a wall of the cartridge for opposition to the disc surface, and the head is movable radially to access concentric data tracks and select therefrom, the actuator energization being controlled in known manner so that the track is followed. The substrate may be a multilayer sandwich enclosing further coils in addition to these on the surface, and an aluminium layer may be included for eddy current damping of movement. |
