| 摘要 |
1456835 Transformers and inductors MULLARD Ltd 15 Nov 1973 [11 Dec 1972] 57060/72 Heading HIT A magnetic core body comprising two ferrite members fixed together to define an air-gap is provided with a metal plate adhesively fastened to a surface of the core but not in the air gap, the plate having a temperature coefficient of expansion different from that of the ferrite, so that on temperature change the difference in expansion causes variation in the air gap and hence the reluctance of the core. The variation may be such as to compensate for temperature variation of inductance of a coil wound on the core. As shown in Fig. 4 a two-part core 1, 2, is provided with a brass strip 6 attached thereto by epoxy resin, differential expansion varying a gap 7. A ring may replace the strip (Fig. 9, not shown). The two core parts may be held together by spring clips or adhesive. Cores having X, E and U configurations are disclosed (Figs. 10, 11 and 12, not shown). The plate may alternatively be secured by polydiacrylic ester adhesives, glass bonding, soldering or welding, and may be located inside the winding space. |
