GB877743A - Improvements in or relating to fluid cooled dynamo-electric machines - Google Patents

Abstract

877,743. Air-gap partitions. GENERAL ELECTRIC CO. Feb. 12, 1960 [Feb. 12, 1959], No. 5099/60. Class 35. In a dynamo-electric machine, of which the rotor and stator are cooled by separate fluids, the rotor is surrounded by and attached to a cylindrical shell to provide a cooling duct around it and to prevent its cooling fluid from entering the gap between the rotor and stator. The shell 12 may be of polyester resin and fibre glass. The stator 2 is enclosed in space 23, the gap 14 between the stator and the cylinder 12 being evacuated by means of a steam ejector 25 to decrease the windage loss. The stator core is cooled by liquid cooled pads sandwiched between core members 2b ; the windings 6 being cooled by liquid flowing through the conductors to conduits 7 and thence to external heat exchangers. To cool the rotor 3 air under pressure is circulated by blower 8 by way of chamber 21 inside casing 4 past heat exchangers 11b, channels 3b in each end of the rotor, axial channels to holes 3a in the rotor, annular duct 13, compartment 22 and heat exchangers 11a to blower 8. The cooling path may include radial passages in the rotor. The pressure is maintained by make-up pump 27. Compartments 21, 22, 23 are sealed by rotating seals 17, 18, 4a. Cylinder 12 is fixed to the rotor 3 by means of spring-loaded slot wedges 26, with extending fingers 26a, the cylinder being slipped over the rotor whilst the wedges are depressed. Alternatively, cylinder 12 may be sprung on to support blocks defining a non-circular periphery (Fig. 3, not shown) on the rotor. Specifications 725,260, 786,725 and 875,360 are referred to.