Interlocking segmented coil array

Abstract

Disclosed is a Segmented Coil Array (“SCA”) for use in rotary electromotive devices, such as motors and generators, which employ multiple coils operating within an axial gap magnetic structure. Individual conductor coils have offset circumferentially extending portions so as to allow interlocking of adjacent coils radially extending portions to form a circular array in which all of the coils' working conductors, which are those in the axial magnetic field, can be oriented in the same plane. This construction allows minimum magnet gap spacing, thus, maximizing the available magnetic flux. The resulting SCA may easily be commuted as a three-phase motor, actuator, or generator. The invention also provides a structure whereby multiple coil arrays and associated magnetic rotors may be alternately stacked in layers so as to further increase the total coil working area within a motor or generator of a given diameter.

1. A segmented coil array for use in rotary electromotive devices with one or two magnet rotors, such as motors and generators, of the type which employ an axial gap magnetic structure, composed of an even multiple of individual wire-wound coils, each coil having substantially the same structure and size and comprising circumferentially extending base portions and radially extending side portions, the radially extending side portions and circumferentially extending base portions joined at their respective ends to define a generally trapezoidal shape: the coil array formed into a ring of partially overlapped alternating coils such that the radially extending side portions of each coil are coplanar. 
     
     
       2. The coil array of  claim 1  wherein each individual coil has offsetting bends near each end of said radially extending side portions which cause the circumferentially extending base portions of the coil to lie outside the plane containing the radially extending side portions so as to allow partial overlapping of each coil by its two adjacent coils. 
     
     
       3. A segmented coil array, according to  claim 2 , in which each coil's circumferentially extending base portions and radially extending side portions define a space containing one radially extending portion from each of its two adjacent coils thereby doubling the density of the coil's working conductors. 
     
     
       4. The coil array of  claim 1  wherein a plurality of the individual coils have offsetting bends near each end of said radially extending side portions which cause the circumferentially extending base portions of the coil to lie outside the plane containing the radially extending side portions so as to allow partial overlapping of each coil by at least two adjacent coils. 
     
     
       5. A segmented coil array, according to  claim 1 , in which the individual coils are over-molded with a moldable material to form a ring of suitable structural integrity and heat tolerance. 
     
     
       6. The segmented coil array of  claim 5  in which the moldable material is epoxy. 
     
     
       7. The segmented coil array of  claim 5  additionally comprising layers of fiber reinforcing fabric. 
     
     
       8. A segmented coil array, according to  claim 1 , herein the coils are oriented to form a linear array. 
     
     
       9. A segmented coil array, according to  claim 1 , wherein the coils are oriented to form a partial ring. 
     
     
       10. The coil array of  claim 1  A segmented coil array for use in rotary electromotive devices with one or two magnet rotors, such as motors and generators, of the type which employ an axial gap magnetic structure, composed of an even multiple of individual wire- wound coils, each coil having substantially the same structure and size and comprising circumferentially extending base portions and radially extending side portions, the radially extending side portions and circumferentially extending base portions joined at their respective ends to define a generally trapezoidal shape: the coil array formed into a ring of partially overlapped alternating coils such that the radially extending side portions of each coil are coplanar,  wherein the individual coils are formed such that the radially extending side portions of a coil have a smaller cross-sectional electrical conductor area than at least one of the circumferentially extending base portions. 
     
     
       11. The coil array of  claim 1 , wherein the multiple individual wire-wound coils A rotary electromotive device comprising two rotors, at least one of which comprises a magnet rotor, said two rotors sandwiching therebetween a segmented coil array to provide two axial magnetic gaps, said segmented coil array being composed of an even multiple of individual wire- wound coils, each coil having substantially the same structure and size and comprising circumferentially extending base portions and radially extending side portions, the radially extending side portions and circumferentially extending base portions joined at their respective ends to define a generally trapezoidal shape, the coil array being formed into a ring of partially overlapping alternating coils such that the radially extending side portions of each coil are coplanar, said coils being  affixed to each other to form a coil platter, having a central axis and known inner and outer diameters, in which the radially extending coil portions are the working conductors, and the working length of said conductors is being approximately 42% of the distance between the central axis of the coil platter and the outer diameter of the coil's working length, thereby optimizing the array for maximum torque, when used as a motor, or voltage production, when used in a generator. 
     
     
       12. The coil array of  claim 1 , wherein the coil array is operably located in a rotary electromotive device, such as a motor or generator, the motor or generator having alternating layers of magnetic material to produce an axial gap magnetic structure, and further having several additional coil arrays arranged in layers of electromagnetic coil arrays which are stacked so as to further increase the total coil area within said electromotive device, each layer of coil structure operating in a separate axial magnetic flux gap formed by the layers of magnetic material. 
     
     
       13. The device of  claim 12  wherein said magnetic material is a disc shaped permanent magnet rotor affixed to a rotatable shaft. 
     
     
       14. The device of  claim 12  wherein said magnetic material is a disc shaped electromagnet rotor affixed to a rotatable shaft. 
     
     
       15. A segmented coil array for use in rotary electromotive devices, such as motors and generators, of the type which employ an axial gap magnetic structure, comprising an even multiple of identically shaped individual wire-wound coils, each coil comprising circumferentially extending base portions, and radially extending side portions joined at their respective ends to form a trapezoid shape, each side portion having offsetting bends at each end of said side portion adjacent to each base portion so that said base portions lie in a plane parallel to said side portions; the coil array formed by arranging a first set of coils into a ring with side portions being adjacent, and overlapping a second set of coils such that the radially extending side portions of each set of coils are all coplanar and the offsetting bends of alternate coils are oriented in different directions so that the base portion of the first set of coils are parallel to the base portions of the second set of coils. 
     
     
       16. A segmented coil array, according to  claim 15 , in which the individual coils are over-molded with a moldable material to form a ring of suitable structural integrity and heat tolerance. 
     
     
       17. The segmented coil array of  claim 16  in which the moldable material is epoxy. 
     
     
       18. The segmented coil array of  claim 15  additionally comprising layers of fiber reinforcing fabric. 
     
     
       19. The coil array of  claim 15  A segmented coil array for use in rotary electromotive devices, such as motors and generators, of the type which employ an axial gap magnetic structure, comprising an even multiple of identically shaped individual wire- wound coils, each coil comprising circumferentially extending base portions, and radially extending side portions joined at their respective ends to form a trapezoid shape, each side portion having offsetting bends at each end of said side portion adjacent to each base portion so that said base portions lie in a plane parallel to said side portions; the coil array formed by arranging a first set of coils into a ring with side portions being adjacent, and overlapping a second set of coils such that the radially extending side portions of each set of coils are all coplanar and the offsetting bends of alternate coils are oriented in different directions so that the base portions of the first set of coils are parallel to the base portions of the second set of coils,  wherein the individual coils are formed such that the radially extending side portions of a coil have a smaller cross-sectional electrical conductor area than at least one of the circumferentially extending base portions. 
     
     
       20. The coil array of  claim 15 , wherein the multiple A segmented coil array for use in rotary electromotive devices, such as motors and generators, of the type which employ an axial gap magnetic structure, comprising an even multiple of identically shaped individual wire- wound coils, each coil comprising circumferentially extending base portions, and radially extending side portions joined at their respective ends to form a trapezoid shape, each side portion having offsetting bends at each end of said side portion adjacent to each base portion so that said base portions lie in a plane parallel to said side portions; the coil array being formed by arranging a first set of coils into a ring with side portions being adjacent, and overlapping a second set of coils such that the radially extending side portions of each set of coils are all coplanar and the offsetting bends of alternate coils are oriented in different directions so that the base portions of the first set of coils are parallel to the base portions of the second set of coils and slightly above and below the co - planar radially extending side portions, the  individual wire-wound coils being affixed to each other to form a coil platter, having a central axis and known inner and outer diameters, in which the radially extending side portions include a working length, and the working length is approximately 42% of the distance between the central axis of the coil platter and the outer diameter of the coil's working length, thereby optimizing the array for maximum torque, when used in a motor, or voltage production, when used in a generator. 
     
     
       21. In a method of manufacturing a stator for an axial gap electrical machine, the steps comprising
   spiral winding a flat ribbon conductor into a plurality of coils having radially extending sides and circumferential ends in substantially the same structure and size around a central void;        forming at least one portion of the plurality of spiral wound coils to offset their circumferential ends from their radially extending sides by machining the radially extending sides of said at least one portion of coils to provide said offset of their circumferential ends; and        arranging the coils into a circumferentially extending stator with their radially extending sides lying generally coplanar by overlapping said at least one portion of coils in the arrangement with their radially extending side portions lying in the central voids of the remaining portion of the unformed coils and with their offset circumferential ends overlapping the circumferential ends of the remaining portion of the unformed coils.     
     
     
       22. A segmented coil array for use in rotary electromotive devices of the type which employ an axial gap magnetic structure, composed of a plurality of individually wound coils comprised of flat ribbon conductor, each coil comprising circumferentially extending base portions and radially extending side portions, the radially extending side portions and circumferentially extending base portions being joined at their respective ends to define a generally trapezoidal shape; a portion of individually wound coils being machined to offset their circumferentially extending base portions from their radially extending side portions, the coil array being formed into a ring of partially overlapped alternating coils such that the radially extending side portions of each coil are coplanar. 
     
     
       23. The coil array of  claim 22 , wherein the individual coils are formed such that the circumferentially extending base portions of a coil have a larger cross- sectional area than one of the radially extending side portions.   
     
     
       24. The coil array of  claim 22  wherein at least one circumferentially extending base portion has less electrical resistance than the radially extending side portions. 
     
     
       25. The coil array of  claim 22  wherein each individual coil has offsets near each end of said radially extending side portions which cause the circumferentially extending base portions of the coil to lie outside the plane containing the radially extending side portions so as to allow partial overlapping of each coil by its two adjacent coils. 
     
     
       26. A coil array, according to  claim 25 , in which each coil's circumferentially extending base portions and radially extending side portions define a space containing one radially extending portion from each of its two adjacent coils thereby doubling the density of the coil's working conductors. 
     
     
       27. A coil array, according to  claim 22 , in which the individual coils are over- molded with a moldable material to form a coil platter with structural integrity and heat tolerance.   
     
     
       28. The coil array of  claim 27  in which the moldable material is epoxy. 
     
     
       29. The coil array of  claim 27  comprising at least one layer of fiber reinforcing fabric incorporated in the coil platter. 
     
     
       30. The coil array of  claim 22 , wherein the multiple individual wound coils are affixed to each other form a coil platter, having a central axis and known inner and outer diameters, in which the radially extending coil portions are the working conductors, and the working length of said conductors is approximately  42 %  of the distance between the central axis of the coil platter and the outer diameter of the coil's working length.