GB1441544A - Housings for electro-magnets - Google Patents

Abstract

1441544 Electromagnets P ISLIKER 25 April 1974 [25 April 1973] 18215/74 Heading H1P A magnetic closure path housing surrounding the coil of an electromagnet is fabricated in two parts of strip magnetic metal folded into U- shape and fitted together one in the other with the legs of the respective parts directed in mutual opposition and one part rotated by 90 degrees respective to the other; the lateral edges of each leg being formed with steps of depth equivalent to the thickness of the metal, and the last width of the legs of one part being equivalent to the gap between the legs of the other part, and the total of the lengths of the steps in any one leg being equal to the leg length. An electromagnet housing (Fig. 1) comprises two U-shaped identical parts 11, 12 with legs 14, 15 and yoke 13 with a central opening for the magnet core (not shown) and threaded fixing bores 16. At half their lengths the lateral edges of the legs are stepped at 18 to a depth equivalent to the metal thickness, and the least width 19 of leg 14 at its free end is equal to the gap between legs 11 and vice versa. Dovetailing lugs 20 of the legs engage recesses 21 of the edges of the yoke for positive interconnection and steps 18 closely engage. A cut-out 23 between lugs 20 gives access to the interior of the housing for the coil connections (not shown). In modifications (Fig. 2, not shown) the steps 18 are staggered, (Fig. 3, not shown) the least width of the legs adjoins the yoke, and (Fig. 4, not shown) the steps are tongued and grooved for locking engagement. Magnetic resistance is minimized, and for AC working the adjacent surfaces are mutually insulated, e.g. with varnish.