Low loss reciprocating electromagnetic device
View Patent ↗The present invention relates generally to reciprocating electromagnetic devices, and more particularly to a construction of a reciprocating electromagnetic device for reducing secondary losses in magnetically-permeable elements, but without compromising manufacturability as required in prior art. The device provides for shaped pole faces to reduce local magnetic flux density and/or interruptions of electrically-conductive paths in the planes of the laminated layers of the stationary element of the device.
1. An electromagnetic device having a linear moving element, a stationary element including magnetically permeable laminate layers, and a region subject to a changing magnetic flux component substantially perpendicular to the laminate layers, the device comprising:
at least one interruption of an electrically-conductive path within a laminate layer in the region.
2. The device of claim 1 , further comprising a pole interface between the linear moving element and the stationary element, the pole interface shaped to locally reduce magnetic flux density.
3. The device of claim 1 , wherein the at least one interruption is at least one slot placed in the laminated layers.
4. The device of claim 3 , wherein the at least one slot runs perpendicular to a planar surface of each laminate layer.
5. The device of claim 1 , wherein the at least one interruption directs magnetic flux into and out of the laminate layers.
6. The device of claim 1 , wherein the at least one interruption directs magnetic flux in alignment with a plane of the laminate layers.
7. The device of claim 1 , wherein the at least one interruption is bordered by or contained in a magnetically-permeable structure capable of accepting adversely directed magnetic flux.
8. The device of claim 1 , wherein the linear moving element is driven by electric current flowing through the stationary element.
9. The device of claim 1 , wherein motion of the linear moving element causes electric current to flow in the stationary element.
10. The device of claim 1 , wherein the device is a reciprocating device and the laminate layers extend transverse to a reciprocating axis.
11. An electromagnetic device having a linear moving element and a stationary element including magnetically permeable laminate layer, and a region subject to a changing magnetic flux component substantially perpendicular to the laminate layers, the device comprising:
means for magnetically interfacing the linear moving element and the stationary element to minimize local magnetic flux density; and
means for interrupting an electrically-conductive path within a laminate layer in the region.
12. A method of reducing eddy-current losses in a region of three-dimensional magnetic flux orientation in an electromagnetic device having a linear moving element and a stationary element including layered laminates of magnetically-permeable material, the method comprising the steps of:
shaping a pole interface between the linear moving element and the stationary element of the electromagnetic device to reduce local magnetic flux density; and
providing an interruption in electrically-conductive paths in the planes of the laminated layers of the stationary element to reduce eddy currents.
13. The method of claim 12 , wherein the step of providing an interruption is provided by placing a void in the layered laminates of the stationary element.
14. The method of claim 13 , wherein the void is at least one slot.
15. The method of claim 14 , wherein the at least one slot runs perpendicular to a planar surface of each laminate layer.
16. The method of claim 12 , wherein the step of providing an interruption is provided by placing an insulated composite between the linear moving element and the stationary element.
17. A reciprocating electromagnetic device having a linear moving element, a stationary element including magnetically permeable laminate layers extending transverse to a reciprocation axis, and a region subject to a changing magnetic flux component substantially perpendicular to the laminate layers, the device comprising:
at least one interruption of an electrically-conductive path within the planes of a laminated layer in the region.
18. The device of claim 17 , further comprising a pole interface between the linear moving element and the stationary element, the pole interface shaped to locally reduce magnetic flux density.
19. The device of claim 17 , wherein the at least one interruption is at least one slot placed in the laminated layers.
20. The device of claim 19 , wherein the at least one slot runs perpendicular to a planar surface of each laminate layer.
21. The device of claim 17 , wherein the at least one interruption directs magnetic flux into and out of the laminate layers.
22. The device of claim 17 , wherein the at least one interruption directs magnetic flux in alignment with a plane of the laminate layers.
23. The device of claim 17 , wherein the at least one interruption is a magnetically-permeable structure capable of accepting adversely directed magnetic flux.
24. The device of claim 17 , wherein the linear moving element is driven by electric current flowing through the stationary element.
25. The device of claim 17 , wherein motion of the linear moving element causes electric current to flow in the stationary element.
26. An electromagnetic device having a linear moving element, a stationary element constructed of a magnetically permeable material, and a region subject to a changing three-dimensional magnetic flux component, the device comprising:
at least one interruption of an electrically-conductive path within the magnetically permeable material in the region.
27. The device of claim 26 , wherein the magnetically permeable material is a composite material.
28. The device of claim 26 , wherein the device is a reciprocating device and the magnetically permeable material is constructed of a wound material.