| 摘要 |
1,272,637. Magnetic heads. MATSUSHITA ELECTRIC INDUSTRIAL CO. Ltd. 21 May, 1969 [21 May, 1968 (2); 22 May, 1968, 12 Oct., 1968; 2 Dec., 1968], No. 26032/69. Heading G5R. Each track of a multitrack head has a single gap 14-17 formed by sets of polepieces 10a, 10b having back-cores 30-33 carrying windings 34-37, the gaps being aligned on two lines 18, 19 perpendicular to the intended transducing direction 20. The polepieces are stacked with spacing blocks 22-28 and are either staggered as shown or arranged in pairs (Fig. 8, not shown) with the top and bottom back cores shaped to increase the distance between the windings. The head may be made by fixing C-corepieces (43-46, Figs. 9-12, not shown) and spacing blocks (50-53) to opposite sides of a common, magnetic plate 42, removing inter-head section and replacing with further spacers, lapping the operative surface, removing the rear face to isolate the polepieces, and attaching the wound back cores. The corepieces and spacers may be of permalloy and bronze respectively, or of ferrites bonded with glass. The reluctances of the respective magnetic circuits may be made equal by choice of material or cross-section of the back cores or by providing gaps between the back cores and corresponding polepieces. |
