GB333616A - Improvements in dynamo electric machinery - Google Patents

Abstract

333,616. Lancashire Dynamo & Motor Co., Ltd., and Howard, J. W. May 17, 1929. Armatures and field magnets, cooling and ventilating.-The core of a dynamo-electric machine is provided with plates of metal of good thermal conductivity interleaved between groups of the core plates, and extending beyond them into longitudinal passages through which cooling air flows, the edge portions of the cooling plates being slotted to form teeth which are bent or twisted. The bent portions may make contact with the walls of longitudinal ducts through which air flows. In the form shown, wherein the invention is applied to a stator, the cooling plates A, in the shape of annular discs or segments, which may be of copper, are placed between groups of laminµ B, Fig. 3, and extend into the air ducts c<1>, Fig. 6. Fins a<1> are formed by notching the parts of the cooling plates which extend beyond the core, and these fins are bent either at right-angles to the plane of the cooling plate, or they may in any other way be inclined thereto. Alternatively, they may be bent down in contact with the core laminee as at a<6>, Fig. 5, and make good thermal contact with the inner peripheries of copper cooling ducts D, Fig. 6. If this arrangement is adopted, a flange a<6>, Fig. 6, may be provided on the cooling plates instead of separate narrow fins. The cooling air passes through the ducts D, which may be fitted with longitudinal heat-transmitting plates d<1>. For cooling a rotor, the fins are formed on the inner periphery, and project into air passages formed inside the rotor laminµ. The cooling plates may be so modified as to provide radial ventilating passages in the core.