| 摘要 |
1,191,776. Inductors. TRW Inc. 28 Nov., 1968 [12 Dec., 1967], No. 56612/68. Heading H1T. An inductive device comprises a flanged bobbin 10 of magnetic material, a wire coil 17 wound on the bobbin, a cylindrical casing 20 of magnetic material enclosing the coil and the flanges, and connecting means for the wire, the periphery of at least one of the flanges being in contact with or uniformly spaced from the wall of the casing. In order to achieve a precise spacing between the flanges and the casing, the bobbin is expanded radially, after insertion in the casing, e.g. by driving wedges (33 and 34, Figs. 2 and 3, not shown) into a slot 14 either until the flanges press against the casing or until a predetermined air-gap, as measured by the reluctance of the magnetic circuit, is achieved. A layer of insulating material may be provided around the peripheries of the flanges to limit movement of the flanges towards the casing during expansion. The cylinder 11 and inner surfaces of the flanges 12, 13 may have a thin coating of insulation (18) and insulation tape (26) may be applied around the coil 17 (Fig. 5, not shown). Cement or resin (27, 28, 29) having high insulation, moisture resistance and bonding properties is applied; and insulating boards 30, 31 complete the assembly. The slot 14 in the bobbin may be filled by a slug of magnetic material. The device may have more than two flanges and more than one sleeve and winding, and unequal flanges. An auxiliary saturating winding may be provided. Specification 1,191,777 is referred to. |
