GB686873A - Improvements in and relating to laminated magnetic cores - Google Patents

Abstract

686,873. Transformers and inductances; electromagnets. BRITISH THOMSONHOUSTON CO., Ltd. Dec. 5, 1950 [Dec. 22, 1949], No. 29756/50. Drawings to Specification. Classes 35 and 38 (ii). A magnetic core for electromagnetic induction apparatus has at least one joint and comprises a plurality of stacked laminations, each of which is shaped to have substantially straight leg and yoke portions at right angles to one another, the laminations being secured together by a line weld positioned at or near the line defined by the joint in the core and across the edges of the lamination on the surface thereof. In a core having butt joints the weld is preferably situated across the edges of the laminations at the line of the joint, whilst in a core having butt and lap joints three line welds per joint are used, two being positioned outside the lines defined by the joints and one weld intermediate these two. In another embodiment a rectangular core is built of substantially planar L- shaped laminations, having line welds across the edges of the core at the lines defined by the joints whilst additional spot welds are made at the joints on the faces of the outermost laminations. Specification 686,872 is referred to.