Permanent magnet for an electric machine and method of making the same
A permanent magnet for use in an electric machine has a magnet thickness and extends along a magnet axis. The permanent magnet defines a groove extending axially along the magnet axis. The groove has a groove depth that is less than the magnet thickness. The groove has a non-straight configuration with respect to the magnet axis.
1 . A permanent magnet for use in an electric machine, wherein the permanent magnet has a magnet thickness and extends along a magnet axis, wherein the permanent magnet defines a groove extending axially along the magnet axis that has a groove depth that is less than the magnet thickness, and wherein the groove has a serpentine configuration with respect to the magnet axis.
2 . The permanent magnet as set forth in claim 1 having a cylindrical configuration extending along and surrounding the magnet axis, with the cylindrical configuration defining a magnet interior.
3 . The permanent magnet as set forth in claim 2 having an outer magnet surface facing away from the magnet axis, wherein the groove is defined by the outer magnet surface.
4 . The permanent magnet as set forth in claim 1 , wherein an insulation material is disposed in the groove.
5 . An electric machine comprising the permanent magnet as set forth in claim 1 , wherein the electric machine further comprises a stator disposed about the permanent magnet.
6 . The electric machine as set forth in claim 5 further comprising a shaft, a compressor wheel coupled to the shaft, and compressor housing defining a compressor housing interior with the compressor wheel disposed in the compressor housing interior.
7 . The electric machine as set forth in claim 6 further comprising a turbine wheel coupled to the shaft and spaced axially from the compressor wheel, and a turbine housing defining a turbine housing interior with the turbine wheel disposed in the turbine housing interior.
8 . The permanent magnet as set forth in claim 1 comprising a first magnet end and a second magnet end spaced from the first magnet end along the magnet axis, wherein the groove has the serpentine configuration along the entirety of the permanent magnet between the first magnet end and the second magnet end.
9 . An electric machine comprising the permanent magnet as set forth in claim 1 , wherein the electric machine further comprises a stator disposed about the permanent magnet.
10 . The electric machine as set forth in claim 9 further comprising a shaft, a compressor wheel coupled to the shaft, and compressor housing defining a compressor housing interior with the compressor wheel disposed in the compressor housing interior.
11 . The electric machine as set forth in claim 10 further comprising a turbine wheel coupled to the shaft and spaced axially from the compressor wheel, and a turbine housing defining a turbine housing interior with the turbine wheel disposed in the turbine housing interior.
12 . A permanent magnet for use in an electric machine, wherein the permanent magnet has a magnet thickness and extends along a magnet axis, wherein the permanent magnet defines a groove extending axially along the magnet axis that has a groove depth that is less than the magnet thickness, wherein the groove has a zig-zag configuration with respect to the magnet axis.
13 . The permanent magnet as set forth in claim 12 comprising a first magnet end and a second magnet end spaced from the first magnet end along the magnet axis, wherein the groove has the zig-zag configuration along the entirety of the permanent magnet between the first magnet end and the second magnet end.
14 . The permanent magnet as set forth in claim 12 , wherein the groove spirals about and along the magnet axis.
15 . The permanent magnet as set forth in claim 14 , wherein the groove has a pitch angle of between 50 and 60 degrees.
16 . The permanent magnet as set forth in claim 12 , wherein an insulation material is disposed in the groove.
17 . A permanent magnet for use in an electric machine, wherein the permanent magnet has a magnet thickness and extends along a magnet axis, wherein the permanent magnet defines a groove extending axially along the magnet axis that has a groove depth that is less than the magnet thickness, wherein the groove has a non-straight configuration with respect to the magnet axis, and wherein the groove has a first groove section extending axially along the magnet axis, and a second groove section extending along the magnet axis parallel to the first groove section, wherein the first and second groove sections have a zig-zag configuration.
18 . The permanent magnet as set forth in claim 17 , wherein the first and second groove sections are continuous with one another.
19 . The permanent magnet as set forth in claim 17 , wherein the groove has a third groove section extending along the magnet axis parallel to the first and second groove sections, and wherein the third groove section has a zig-zag configuration.
20 . A permanent magnet for use in an electric machine, wherein the permanent magnet has a magnet thickness and extends along a magnet axis, wherein the permanent magnet defines a groove extending axially along the magnet axis that has a groove depth that is less than the magnet thickness, wherein the groove has a non-straight configuration with respect to the magnet axis, and wherein the groove has a first groove section extending circumferentially about the magnet axis, and a second groove section extending circumferentially about the magnet axis parallel to the first groove section, and wherein the first and second groove sections have a zig-zag configuration.