| 摘要 |
1,237,410. Transformers; inductors. SMIT NIJMEGEN ELECTROTECHNISCHE FABRIEKEN N.V. 6 Aug., 1968 [14 Aug., 1967; 12 Feb., 1968], No. 37552/68. Heading H1T. A winding 1 for a transformer or choke coil is compressed in the axial direction by means of hydraulically or pneumatically expanded bags 4 placed between one or both end faces of the winding and an envelope 6, 7 wrapped around the winding. In Fig. 1, pressure rings 2, 3 are placed adjacent the end faces of the windings and an annular bag is placed against ring 3. A paper cap 5 is placed over the bag and bundles or bands of glass fibre wires 6 are wound around the assembly. Gas or liquid under pressure is then supplied to the bag to exert the required compressive force on the winding. The assembly may then be coated in a hardening synthetic material 7 to render the envelope gas-andliquid-tight and the space 15 inside the envelope filled with transformer oil. If two concentric windings (as 16, 17, Fig. 3, not shown) are to be placed on one core leg, they may be separated by an insulating tube (19) and wrapped in a common envelope, but provided with separate annular bags (22, 23). The pressure ring may be formed with a projecting portion so that the adjacent surface of the bag is indented (Fig. 4, not shown). In this embodiment the bag(s) may be made of rubber or synthetic material reinforced by fibrous substances. In a further modification (Figs. 5, 6, not shown) a plurality of angularly-spaced cupshaped bags are disposed between two complementary-shaped wooden pressure rings. The bags may be constituted by bellows of metal, which may also act as potential-controlling rings. |
