GB172939A - Improvements in the high-voltage slot-windings of electrical machines and in the process for the manufacture of same - Google Patents

Abstract

172,939. Akt.-Ges. Brown, Boveri, et Cie. Dec. 16, 1920, [Convention date]. Insulation.-In a method of insulating hightension windings in half-closed slots, the slot, Fig. 1, is first lined with an insulating layer a, after which a lower U-shaped channel b is inserted. The former-wound coil c is introduced laterally wire by wire through the slot opening d, the layers being insulated from one another by strips g. A U-shaped channel e is next slipped over the coil in an axial direction, and a wedge f firmly supports the whole. In a modification, Fig. 2, the walls of the channels are wedgeshaped, there being thus a lateral pressure upon the coil. The abutting surfaces of the insulating members are made smooth, and are preferably covered with insulating varnish. If it is required to lengthen the surface leakage path for high voltages, the lower channel b may have double walls, the flanks of the upper channel being adapted to fit into the spaces between the walls. The slot wedge f may be dispensed with if the upper and lower channel members are pressed together inside the slot until the insulating varnish causes them to adhere.