GB500487A - Improvements in frames for dynamo electric machines - Google Patents

Abstract

500,487. Dynamo - electric machines. BRITISH THOMSON-HOUSTON CO., Ltd., and. POLLOCK, A. A. Aug. 9, 1937, No. 21899. [Class 35] [Also in Group XXII] In a dynamo-electric machine having a magnet frame consisting of a ring f with one or more plane annular stiffening ribs, the ribs are of polygonal form and are formed from a number of straight pieces c, Fig. 1, joined together. The magnet frame is constructed of steel bars bent to form a ring or two half rings. Holes b may be formed at the corners of the polygon to constitute lifting eyes. The inner edges of the bars may be shaped to a circle to conform with the outer periphery of the ring f. In a modification, the stiffening rib is formed from a bar e, Fig. 2 having notches a therein at regular intervals, the bar being bent until the notches close whereby a regular polygon or a portion of a polygon is formed, the contiguous edges of the material being secured together. The notches may terminate in holes b constituting lifting eyes and they may be flame cut. The polygon may also be flame cut to a circle to fit outside the magnet ring and may be electrically welded thereto. Alternatively, the ribs may be placed against the ends of the magnet ring, and where the ring is axially divided, an additional rib may be placed between the two portions of the ring as shown in Fig. 6.