Electric machine rotor and method of forming
A method and apparatus for forming a rotor for an electric machine includes serially adding layers of material to form a rotor body having a radially-extending post configured to receive a set of electrically-conductive windings, and also having a radially-extending winding end turn support formed contiguously from the rotor body.
1. A method of forming a rotor for an electric machine, the method comprising:
serially adding layers of material along a build direction to form a rotor body having a radially-extending post configured to receive a set of electrically-conductive windings, and the rotor body having a radially-extending winding end turn support, and wherein the radially-extending post and the radially-extending winding end turn support are formed contiguous—with the rotor body; and
removing material from the rotor body by relative rotation of one of the rotor body or a removal tool such that a radial segment of the radially-extending winding end turn support is not contiguous with the rotor body.
2. The method of claim 1 wherein the serially adding layers of material further comprises serially adding layers of material along the build direction to form the rotor body with a bolster between the radially-extending post and the radially-extending winding end turn support.
3. The method of claim 2 wherein the removing further comprises removing material from the bolster.
4. The method of claim 1 wherein the serially adding layers of material further comprises serially adding layers of material along the build direction to define a recess in the rotor body between the radial segment of the radially-extending winding end turn support and the radially-extending post.
5. The method of claim 1 , further comprising forming an exposed surface of the radially-extending post via the removal tool.
6. The method of claim 5 wherein forming the exposed surface includes polishing the exposed surface to have a surface roughness average between 0.4 and 3.0 micrometers.
7. The method of claim 1 wherein removing further comprises removing material from the rotor body by relative rotation of one of the rotor body or the removal tool, wherein the removal tool comprises a computer-numerical-control (CNC) lathe having a carbide tool.
8. The method of claim 1 , further comprising forming a conduit within the rotor body defining a fluid passage having at least one U-shaped bend.
9. The method of claim 8 wherein forming the conduit comprises forming the at least one U-shaped bend with a first leg extending radially, a second leg extending radially, and a third leg extending circumferentially thereby connecting the first leg to the second leg.
10. The method of claim 9 wherein forming the conduit comprises forming the at least one U-shaped bend of the conduit within the radially-extending winding end turn support.
11. The method of claim 8 wherein forming the at least one U-shaped bend further comprises forming a first U-shaped bend in a first portion of the conduit, forming a second portion of the conduit extending axially and fluidly coupled to the first portion of the conduit, and forming a second U-shaped bend in a third portion of the conduit fluidly coupled to the second portion of the conduit.
12. The method of claim 8 wherein the serially adding layers of material further comprises serially adding layers of material along the build direction to form a first U-shaped bend within a first winding end turn support and a second U-shaped bend within a second winding end turn support.
13. The method of claim 1 , further comprising winding a set of electrically-conductive windings about the radially-extending post, wherein the radially-extending winding end turn support radially underlies an end turn portion of the set of electrically-conductive windings.