Patent ID: 6548930
Filing Date: 2003-04-15
Classification: H02K

Abstract:
An electric motor for a fluid pump comprising:(a) a rotor assembly having coils arranged on a shaft; and (b) a stator assembly surrounding the rotor assembly and defining an annular fluid passage between the rotor and the stator, the stator assembly including: (1) a tubular stator housing having an inner wall and a diaphragm portion that covers circumferential stops of the stator housing; (2) a plurality of magnetic shells disposed in contact with the tubular housing inner walls at arcuately spaced apart locations, wherein the shells have arcuate inner surfaces that are all the same radial distance from the tubular housing inner wall and the rotor assembly; and (3) a spring element located in each space between each pair of adjoining magnetic shells to hold the shells in assembled position within the tubular housing, wherein each spring element has a substantially smooth arcuate surface that is substantially level with a radially inner boundary of the magnetic shells.