GB1253145A - - Google Patents

Abstract

1,253,145. Inductors. GENERAL ELECTRIC CO. Ltd. 15 May, 1970 [24 Feb., 1969], No. 9682/69. Heading H1T. An electromagnetic choke comprises a central magnetic core part consisting of two stacks of T-shaped laminations 1, 2 arranged end-toend into H form, a coil 4 wound on the central limb of the H core part, four outer magnetic core parts 6 consisting of a stack of laminations of L-shape in cross-section which core parts extend lengthwise parallel to each other and to the central limb and are located one at or near each corner of the H core part across the space between the opposed parallel limbs thereof so as to provide an outer shell return path for the magnetic circuit of the core and to substantially enclose the coil, and an outer casing 12 which clamps the core parts in position. Metal side-plates (9) (Fig. 2, not shown) may be held in position by, and spot-welded to, inwardly turned flanges (8) (Fig. 2, not shown) extending along the sides of the outer casing 12. The interior of the choke is filled with a suitable potting compound, such as a polyester silica resin, and closed by a front plate welded across the mouth of the outer casing. Said front plate is apertured to permit access to a terminal block 10 attached to the inner side of the casing, the choke coil being connected to the terminals of the block. The core may be provided with one or more suitably positioned air gaps 3 and a sleeve 5 fitted around the core centre limb.