GB1325239A - Magnetic head and method of manufacture thereof - Google Patents

Abstract

1325239 Magnetic heads AMPEX CORP 23 Aug 1971 [28 Aug 1970] 39357/71 Heading G5R Magnetic heads 10 having a non-magnetic gap 11 in a magnetic core 13, 14 are formed with glass islands or pockets 15, 16 at each end of the gap 11 to reduce edge erosion 18, 19. A plurality of such heads 10 are manufactured from two blocks 26, 27 of magnetic material, e.g. ferrite, by (a) forming a plurality of spaced notches 29 in an edge 28 of the block 26, to define lands 39; (b) forming an elongate groove 40 in a plane surface 41 of the block 27; (c) holding the blocks 26, 27 together, Fig. 4 (not shown) with the groove 40 overlying part of the notches 29 and with a non-magnetic spacer (53) interposed between lands 39 and confronting strip 51 of the block 27; (d) bonding the blocks 28, 27 together by placing one or more rods (56), Fig. 4 (not shown) or (72), Fig. 9 (not shown) of glass material in the groove 40, and heating to a temperature at which the glass melts and flows by capillary action into the notches 29, and out of the groove 40 so that a winding window 21 is formed in the head 10; (e) slicing the blocks 26, 27 along planes (64), Fig. 7 (not shown) parallel to and bisecting the notches 29. Glass also flows into the gap formed below spacer (53) between lands 39 and the strip 51, and a top portion (61), Fig. 6 (not shown) of both blocks 26, 27 is lapped off, thereby removing spacer (53) and leaving a glass-filled gap 11. Spacer (53) may be formed by a particle deposition process. Alternatively, Fig. 9 (not shown), the spacer may be a shim (71) of a glass of higher melting point, which is not caused to melt.