GB212664A - Improvements in electric motors - Google Patents

Abstract

212,664. Lancashire Dynamo & Motor Co., Ltd., Wood, A. P., McLeod, R. S., and Stansfield, W. Dec. 19, 1922. Armatures and field magnets, cooling. - In electric motors of the squirrel-cage type wherein the rotor bars are provided with high-resistance end connectors, these connectors are located at the end of the motor casing beyond the stator windings and the inlets and outlets for the cooling-air are arranged so that the air utilized to cool the stator windings and the core plates is not affected by the air heated by cooling the said end connectors. In the construction shown in Fig. 2, the end connectors G are supported by an extension c<2> of the rotor and are located in an end compartment between the end E of the motor casing and a partition formed by the extension c<2> and a fixed ring F with which it makes a running joint. The connectors are cooled by air which enters through inlets e<2> in the end cover E and leaves bv an outlet J. The stator windings &c. are cooled by air from an inlet I passing to an outlet O. At the opposite end of the machine the inlet I is arranged close to the end cover if ordinary connectors are used at that end of the, rotor, but connectors G<2> similar to the connectors G, and of smaller resistance, may be provided and cooled by air either from the inlet I as shown, or from a special inlet in the end cover at that end of the machine, the air leaving by an outlet J<2>. In the construction shown in Fig. 4, air from an inlet I first cools the windings &c. and is then divided by the partition F into two streams, one of which cools the end connectors G, and the two streams leave by outlets 0, J. In the consruction shown in Fig. 6, both ends of the machine are arranged similarly and the air inlets I<2> are placed centrally. Specification 198,726 is referred to in the Provisional Specification.