Patent ID: 9735630
Date: 2017-08-15
CPC Classifications: H02K

Claim:
1. A laminated core for an electrical machine, comprising: a plurality of laminations each having a radially outer edge defined by at least a first, a second and a third radius, each of the first, second and third radii being different sizes, wherein the first, second and third radii are separated by a step so as to provide circumferential projections which subtend about an angle and which change from one circumferential projection to an adjacent circumferential projection by a step, wherein the plurality of laminations are configured such that the first, second and third radii define a helical channel in a surface of the laminated core for a flow of a cooling fluid, the channel has a base defined by the first radius, and at least one circumferential side wall having a radial height defined by the third radius and formed by the second radius of one of the plurality of laminations, wherein the second radius is greater than the first radius and less than the third radius.