Axial field electric machine

Abstract

An axial field electric machine having an improved efficiency includes a number of magnetic elements (e.g., as a rotor) as annular disks magnetized to provide multiple sector-shaped poles. Each sector has a polarity opposite that of an adjacent sector, and each sector is polarized through the thickness of the disk. The poles of each disk are aligned with opposite poles of each adjacent magnet. Metal members adjacent the outermost disks contain the flux. The axial field electric machine also includes one or more conductor elements (e.g., as a stator) which include a number of conductor phases that traverse the flux emanating between poles of axially adjacent magnetic elements. The design of the axial field electric machine including the gap spacing between adjacent magnetic elements, the transition width between adjacent poles on each magnetic element, the number of poles, the number and width or conductor phases in the conductor element is based on the physical characteristics of the magnetic elements to increase efficiency.

What is claimed is:  
     
         1 . An electric machine comprising: 
 a shaft having an axis and adapted for rotation about said axis;    a rotor including: 
 first and second magnetic elements, each having an outer face and a plurality of adjacent magnetic poles, said first and second magnetic elements are axially displaced from one another and coupled to said shaft; and  
 first and second endplates coupled to the outer faces of said first and second magnetic element, respectively, each of said endplates being made of a material so that flux from a first magnetic pole flows to adjacent magnetic poles of the first and second magnetic elements.  
   
     
     
         2 . A conductor element for an electric machine, comprising: 
 a substrate having first and second sides, a center and a periphery;    a plurality of first conductors disposed on the first side of said substrate,    each of said first conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate.    the radial portions of said first conductors and the substrate form a volume wherein said volume has a fill factor of between 60 and 90%.    
     
     
         3 . The conductor element of  claim 2  further comprising: 
 a plurality of second conductors disposed on the second side of said substrate;  
 each of said second conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate;  
 said substrate including a plurality of inter-side through-holes extending between and coupling selected one of the first conductor to selected ones of the second conductors.  
 
     
     
         4 . A conductor element comprising: 
 a plurality of subassemblies, each subassembly including: 
 a substrate having first and second sides, a center and a periphery;  
 a plurality of first conductors on the first side of said substrate, ea 2 h of said first conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate;  
 a plurality of second conductors disposed on the second side of said substrate;  
 each of said second conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate; and  
 said substrate including a plurality of inter-side through holes extending between and coupling selected ones of the first conductors to selected ones of the second conductors; and  
   a plurality of terminal through holes extending between adjacent subassemblies and coupling selected ones of the first and second conductors in one subassembly to selected ones of the first and second conductors in an adjacent subassembly;    the radial portions of said first and second conductors and the substrate of said subassembly form a volume wherein said volume has a fill factor greater than 60%.    
     
     
         5 . The conductor element of  claim 4  wherein said fill factor is greater than 80%.  
     
     
         6 . An axial field electric machine comprising: 
 a shaft;    a plurality of conductor elements, each conductor element including a number of conductors and at least one pin for selectively coupling a conductor from one of said conductor elements to another of said conductor elements; and    a plurality of magnetic elements capable of being mounted to said shaft, each of said magnetic elements being mounted adjacent to at least one of said conductor elements;    said conductor elements and said magnetic elements are capable of being selectively added to and subtracted from said axial field electric machine.    
     
     
         7 . A stator for an axial field electric machine, comprising: 
 a plurality of annular casings, each enclosing a conductor phase assembly and removably connectable to an adjacent one of said annular casings along an axis, said conductor phase assembly including a winding having an elongated conductor portion oriented in a generally radial direction with respect to said axis; and    a pin electrically connecting a conductor phase assembly of a casing to a conductor phase assembly of an adjacent casing.    
     
     
         8 . A conductor element comprising: 
 a plurality of conductor phases extending from a periphery toward a center of said conductor element, each of said conductor phases having a generally rectangular cross-section and a width tapering toward the center of said conductor element.    
     
     
         9 . A method for selecting a voltage in a motor/generator, comprising the steps of: 
 providing a stator comprising a plurality of annular casings, each enclosing a plurality of conductor phase assemblies and removably connectable to another one of said annular casings along an axis;    disposing each casing at an angular orientation with respect to an adjacent annular casing; and    electrically connecting conductor phase assemblies of said plurality of annular casings to one another.    
     
     
         10 . A method of manufacturing an axial field electric machine comprising: 
 creating a number of adjacent magnetic poles in a magnetic element such that a transition area is present between adjacent magnetic poles;    mounting said magnetic element to a shaft capable of rotation;    providing a conductor element capable of being mounted adjacent to said magnetic element, said conductor element including a number of conductors extending from a periphery to a center of said conductor element, said conductors having a maximum width less than or equal to a width of said transition area.    
     
     
         11 . The method of  claim 10  wherein said conductors extending from the periphery to the center of said conductor element have a width substantially equal to the width of the transition area.  
     
     
         12 . An axial field electric machine comprising: 
 a conductor element including a plurality of subassemblies, each subassembly comprising: 
 a substrate having first and second sides, a center and a periphery;  
 a plurality of first conductors on the first side of said substrate,  
 each of said first conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate;  
 a plurality of second conductors disposed on the second side of said substrate;  
 each of said second conductors including a radial portion extending in a generally radial direction from the periphery to the center of said substrate; and  
 said substrate including a plurality of inter-side through holes extending between and coupling selected ones of the first conductors to selected ones of the second conductors; and  
 a plurality of terminal through holes extending between adjacent subassemblies and coupling selected ones of the first and second conductors in one subassembly to selected ones of the first and second conductors in an adjacent subassembly;  
   first and second magnetic elements disposed axially adjacent to said first and second sides of said conductor element, each of said first and second magnetic elements having an outer face and a plurality of adjacent magnetic poles; and    first and second endplates coupled to the outer faces of said first and second magnetic element, respectively, each of said endplates being made of a material so that flux from a first magnetic pole flows to adjacent magnetic poles of the first and second magnetic elements;    said conductor element and said first and second magnetic elements are adapted to rotate relative to each other.    
     
     
         13 . The axial field electric motor of  claim 12  further comprising: 
 a shaft capable of rotation, said first and second magnetic elements being coupled to said shaft.  
 
     
     
         14 . A method of manufacturing an conductor element, comprising: 
 (a) providing a composite material sheet including a first conductive material layer coupled to a first side of a substrate;    (b) selectively etching said first conductive material layer so as to form a plurality of first conductors, each of said first conductors including a radial portion extending in a generally radial direction from a periphery to a center of said conductor element.    
     
     
         15 . The method of  claim 14  wherein in said providing step, said composite material sheet further includes a second conductive material layer coupled to a second side of said substrate, the method further comprising: 
 (c) selectively etching said second conductive material layer so as to form a plurality of second conductors, each of said second conductors including a radial portion extending in a generally radial direction from the periphery to the center of said conductor element.  
 
     
     
         16 . The method of  claim 14  fuirther comprising: 
 (c) depositing a dielectric material between the radial portions of adjacent first condcutors in said conductor element.  
 
     
     
         17 . The method of  claim 14  further comprising: 
 (d) providing a plurality of inter-side through-holes extending between and coupling selected ones of the first conductors to selected ones of the second conductors.  
 
     
     
         18 . The method of  claim 17  further comprising: 
 (e) depositing a dielectric material between the radial portions of adjacent first conductors and adjacent second conductors in said conductor element.  
 
     
     
         19 . The method  claim 18 , wherein performing steps (a) through (e) produces a first subassembly of said conductor element, the method further comprising: 
 (f) repeating steps (a) through (e) to produce a second subassembly of said conductor element;    (g) providing an insulative material between said first and second subassemblies of said conductor element; and    (h) providing a plurality of terminal through holes extending between said first and second subassemblies and coupling selected ones of the first and second conductors in the first subassembly to selected ones of the first and second conductors in the second layer.