Manufacturing processes for 2.5D laminated stacks

Laminated cores for radial flux electrical machines are generally prismatic, such that each individual lamination is identical. This approach lends itself to cost-effective die stamping in medium- to high-volume production. However, in some applications it may be advantageous to employ non-prismatic designs, for example, by varying geometry lamination by lamination in order to approximate three-dimensional (3D) features in an approach that might be called 2.5D. Alternatively these features might be cut into a core after stamping and assembly. These approaches could be employed to create geometric features to assist assembly, or to incorporate sensors or cooling channels within the stator. We explore some of these opportunities and evaluate two different manufacturing processes. We present both the use of remote laser cutting to manufacture a complete 2.5D stator for low volume production, and the use of subtractive machining to add-in features to prismatic designs for higher volume production.