GB1181194A - Submersible Electric Motors - Google Patents

Abstract

1,181,194. Submersible electric motors. V. K. SMITH. 1,9 April, 1968, No. 18566/68. Heading H2A. A submersible electric motor 1, e.g. for a domestic well pump, comprises a tubular shell 10 around a stator assembly 2 in whose bore 3 is a liner 20 within which bearings 40, 80 rotatably support a rotor assembly 4, end rings 11, 12 adjacent the stator assembly and disposed between and welded to the shell and liner while being held concentric with the stator bore, and end cores 61, 94 mounted one at each end of the motor one, 61, having a central axially outwardly extending part-spherical socket 63 engaging part-spherical surfaces 55 on the axially outer face 52 of the adjacent bearing 40 in order to assist in maintaining concentricity of the bearing with the bore. As shown, the stator assembly comprises a stack of yoke laminations 7 shrunk upon a stack of spider laminations 5 in whose exterior slots are windings 6 embedded in an epoxy casting resin 26 and whose leads 18 emerge through a neoprene gasket 30 and support 99, whilst the rotor is of the squirrel-cage type. A metal thrust washer 37 is keyed at 35, 36 to rotate with the rotor shaft 32, and the bearings 40, 80 have axial and radial grooves 46, 47 (Fig. 5), 85 for a liquid lubricant which may be mainly a propylene glycol/distilled water mixture. The motor is sealed against the entry of the immersing well water by diaphragms 70, 88 of which the former is so resiliently constructed as to permit thermal expansion of the lubricant: The shell, end rings, and liner are all of stainless steel.