| 摘要 |
1,140,040. Selective printing. STANDARD TELEPHONES & CABLES Ltd. 31 May, 1966, No. 24191/66. Heading B6F. [Also in Division G5] Selective electro-magnetic printing heads or magnetic tape recording heads (see Divisions G4-G6) comprise a plurality of contiguous cores 11 of soft iron provided with closely wound, single-turn windings 12 the ends of which are soldered to terminals 13 and the contiguous cores 11 are embedded in an epoxy resin block 14. Surface of block 14 through which the core ends are exposed may be coated with a wear resistant plastics film, or silicon nitride may be deposited thereon by a glow discharge process. Alternatively the epoxy resin may be modified by addition of a wear resistant filler such as amorphous silica. Heads are produced by locating the ends of cores 11 (Fig. 2) in a brass plate, which is surrounded by side-plates 6 serving also as supports for terminals 13. Following casting of the epoxy resin the brass plate 3 and side-plates 6 are removed and ends of cores 11 finished flush with the epoxy resin surface. |
