Armature for an electromotive device
View Patent ↗An inductive coil for an electromotive device includes a pair of concentric conductive sheet metal winding portions each comprising a plurality of axially extending conductive bands each being separated from an adjacent conductive band by a space, each of the conductive bands of one of the winding portions being coupled to one of the conductive bands of the other winding portion, the winding portions being encapsulated in a material that extends through at least one of the spaces from an exterior portion of the induction coil to an interior portion of the induction coil.
1. An inductive coil for an electromotive device, comprising:
a pair of concentric inner and outer sheet metal winding portions separated by a continuous non-conductive fiber strand extending around the circumference of the inner winding portion a plurality of times to form an insulation layer, each of the winding portions comprising a plurality of axially extending conductive bands with each of the conductive bands of one of the winding portions being coupled to one of the conductive bands of the other winding portion, the inductive coil being encapsulated with a material that impregnates the winding portions and the insulation layer.
2. The inductive coil of claim 1 further comprising a second continuous non-conductive fiber strand extending around the circumference of the outer winding portion a plurality of times.
3. The inductive coil of claim 2 wherein the second continuous non-conductive fiber stand forms an outer layer around the circumference of the outer winding, and wherein the material encapsulating the coil impregnates the outer layer.
4. The inductive coil of claim 1 wherein the continuous non-conductive fiber strand extends around the circumference of the inner winding portion from one of the inner winding portion ends to the other inner winding portion end.
5. The induction coil of claim 4 further comprising a second non-conductive fiber strand extending around the circumference of the insulation layer a plurality of times from one end of the inner winding portion to the other end of the inner winding portion to form a second insulation layer between the inner and outer winding portions.
6. The inductive coil of claim 5 wherein the material encapsulating the coil impregnates the second insulation layer.
7. The inductive coil of claim 1 wherein each space separating the conductive bands is less than 1.5 time the thickness of every one of the conductive bands.
8. The inductive coil of claim 1 wherein the continuous non-conductive fiber strand comprises glass.
9. The inductive coil of claim 8 where the continuous non-conductive fiber strand comprises a thickness between 0.00030-0.00075 inch.
10. The inductive coil of claim 1 wherein the encapsulation material comprises polyimide.
11. The inductive coil of claim 1 wherein each of the winding portions comprises precision machined and rolled copper.
12. The inductive coil of claim 1 wherein each of the conductive bands comprises a tensile strength greater than 40,000 psi.
13. The inductive coil of claim 1 wherein each of the conductive bands comprises a yield strength greater than 30,000 psi.
14. The inductive coil of claim 1 wherein each of the conductive bands comprises a percent elongation less than 20%.
15. The inductive coil of claim 1 wherein each of the conductive bands comprises a hardness greater than a Brunell number of 70.
16. The inductive coil of claim 1 further comprising an electrically insulated metal flywheel coupled to an interior portion of the induction coil.
17. The inductive coil of claim 16 wherein the electrical insulation comprises an anodized outer surface of the flywheel, the anodized outer surface being in contact with the interior portion of the induction coil.
18. The inductive coil of claim 17 wherein the metal comprises aluminum.