| 摘要 |
1,116,195. Coils. SQUARE D. CO. 8 Feb., 1967 [8 Feb., 1966], No. 5931/67. Heading HIP. An encapsulated electrical coil comprises an annular coil body formed of a plurality of turns of insulated conductor, an insulative cord forming a plurality of peripherally spaced convolutions about the coil body and passing through the central opening, and a layer of insulating material encapsulating the coil body and the cord. As shown, Fig. 1, a coil body 10 is wound on a removable former and the ends of the wire are connected to a terminal board 15. An insulative cord 24 is wound round the coil and terminal board and the assembly is then placed in a mould and encapsulated with an insulating material Figs. 2 to 4 (not shown). The cord spaces the coil body from the walls of the mould to determine the thickness of the insulating material surrounding the coil. The encapsulant may be liquid and flows along the passages formed by the helically wound cord. The cord may be of vegetable fibre, which may be impregnated with insulating varnish, or of synthetic material. The encapsulant may be thermosetting, or may be of a type which hardens at room temperature with or without a hardener, e.g. an epoxy compound. |
