GB374595A - Improvements relating to the ventilation or cooling of electric motors - Google Patents

Abstract

374,595. Dynamo-electric machines. FILMER, C., 55, Ashfield Road, Altrincham, Cheshire and ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Crown House, Aldwych, London. May 11, 1931, No. 13924. [Class 35.] Cooling and ventilating.-A motor of the enclosed type for rotating a fan or propeller for drawing or driving a fluid, e.g. air, through a wind trunk or casing, is provided with a casing formed in part by a hollow fairing 7 and in part by the motor frame 3, and a fan and cooling channels are so provided within the casing that, on the one hand, the active material of the stator is adapted to be cooled directly by the main external air or fluid blown or propelled by the motor, and on the other hand the imprisoned air or gas is circulated so as to cool the rotor and provide additional cooling for the stator, the imprisoned air being directed, during its circulation, so that it flows on the inner surface of the fairing, the outer surface of which is cooled by the main external air or fluid propelled by the motor. In the construction shown, the stator yoke or frame 3 has a plurality of lugs 4 carrying radial arms 5 by means of which the motor is supported axially in a wind trunk or casing, a fan or propeller (not shown), mounted on the end 1 of the motor shaft 2, being adapted to draw fluid, e.g. dust-laden air, over the fairing 7 and frame 3 in the direction shown by the arrows 6. The bracket 8 for the bearing 9 at the commutator end of the motor is of reduced diameter, as shown, and is provided with openings 11 for the passage of air. A fan 20, mounted on the end of the rotor shaft, and surrounded by a guide 23 secured to the bracket 8, effects the circulation of the internal air in the direction shown by the arrows. The armature is provided with cooling channels 18, and baffles 14, 15, 16 are arranged to direct the circulation of the air. When the motor is of the alternating-current type, the stator core may be provided with axially extending ducts or channels.