GB1395212A - Electric machines especially three-phase generators for motor vehicles - Google Patents

Abstract

1395212 Adjustably securing stator cores in electric machine housings ROBERT BOSCH GmbH 1 May 1972 [28 June 1971] 20067/72 Heading H2A In an electrical machine, e.g. a 3-phase generator 10 for a motor vehicle, having a stator core 16 and a housing comprising a pair of, e.g. cup-shaped bearing plates 12, 13 by which a rotor is rotatable inside the stator core, the stator core has a part, e.g. a ring 17 which projects radially outwardly beyond the outer diameter of a stack of laminations forming the core and into a cylindrical gap between the two bearing plates, the stator core prior to the part being clamped between the bearing plates having, in the absence of radial locating means for the stator, a degree of freedom of radial movement between itself and the bearing plates in order that the core may be adjusted radially to establish a substantially uniform radial air gap between the stator and the rotor, the part when such adjustment has been effected being clamped between the bearing plates which convey a force frictionally locking the core to the plates. Whilst as shown the ring 17, of either magnetizable or non-magnetic material, is disposed mid-way of two core halves 16a, 16b, e.g. of edgeway wound laminations, it may alternatively be disposed either at the end of, or spaced from the end of, the core. After riveting the laminations together by rivets 16c the air gap 17a left by the ring may be removed or reduced by pressing the laminations together (Fig. 3) or, alternatively, the ring may, Figs. 5 and 6, have teeth of either the same size or smaller than those of the laminations. The ring may be a core lamination but of greater outside diameter. The bearing plate clamping surfaces may be machined or embossed to increase the frictional forces, the stator may be spotwelded to the housing, and the space therebetween may be filled with plastics material, after the adjustment.