Armature for an electromotive device

Abstract

An armature apparatus for brushless and brush type electric motors and a manufacturing method for same armature. The armature represents and improved design for electric motors having a rigid, thinwall configuration and high conductor packing density in the magnetic flux air gap that results in motors with higher torque and speed capabilities and the ability to operate at higher temperature than conventional motor designs. The armature is fabricated from pre-machined copper sheet metal parts with an electrical conductor pattern of numerous axially extending conductive bands. These precision machined sheet metal parts are cold rolled to form two work hardened cylinders, each cylinder having a complimentary pattern of electrically conductive bands creating a half-electric circuit. The two cold rolled metal cylinders are sized such that the smaller diameter inner cylinder fits inside the larger diameter outer cylinder. The surface of the inner cold rolled cylinder is over-wrapped with fiber strands, woven in several layers to provide physical spacing and electrical insulation. The fiber wrapped inner cylinder is placed inside the larger outer cylinder radially oriented to ensure that an electrical circuit is created by welding the inner and outer cylinder at the conductor tabs. The surface of this cylinder assembly is over-wrapped with fiber strands, woven in several layers and holding the two cylinders together. The entire armature coil is encapsulated in a potting material to add composite strength and electrical insulation. The result of this assembly is a freestanding, ironless core, inductive armature coil for brushless or brush type electric motors.

1 . An inductive coil for an electromotive device, comprising: 
 a pair of concentriclly disposed 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 separated by an encapsulation material introduced between the winding portions while the winding portions are concentrically disposed.    
     
     
         2 . The inductive coil of  claim 1  wherein the encapsulation material is introduced between the winding portions during an encapsulation process.  
     
     
         3 . The inductive coil of  claim 2  wherein the encapsulation process comprises dipping the concentric winding portions into an encapsulating material.  
     
     
         4 . The inductive coil of  claim 3  wherein the encapsulation process further comprises centrifuging the dipped concentric winding portions.  
     
     
         5 . The inductive coil of  claim 1  wherein the encapsulation material is introduced between the winding portions after the winding portions are coupled together.  
     
     
         6 . The inductive coil of  claim 1  wherein the winding portions are further separated by a non-conductive filament wrapped around said one of the winding portions before the encapsulation material is introduced between the winding portions.  
     
     
         7 . The inductive coil of  claim 6  further comprising a second non-conductive filament wrapped around the other winding portion before the encapsulation material is introduced between the winding portions.  
     
     
         8 . The inductive coil of  claim 1  wherein the conductive sheet metal winding portions are concentrically disposed by telescoping said one of the winding portions into the other winding portion.  
     
     
         9 . An inductive coil for an electromotive device, comprising: 
 a pair of concentriclly disposed 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 concentrically disposed by telescoping said one of the winding portions into the other winding portion.    
     
     
         10 . The inductive coil of  claim 9  wherein the winding portions are separated by a non-conductive filament wrapped around said one of the winding portions before the winding portions are concentrically disposed.  
     
     
         11 . The inductive coil of  claim 10  further comprising a second non-conductive filament wrapped around the other winding portion, and an encapsulation material introduced between the winding portions while the winding portions are concentrically disposed.  
     
     
         12 . The inductive coil of  claim 9  wherein the winding portions are separated by an encapsulation material introduced between the winding portions while the winding portions are concentrically disposed.  
     
     
         13 . The inductive coil of  claim 12  wherein the encapsulation material is introduced between the winding portions during an encapsulation process.  
     
     
         14 . The inductive coil of  claim 13  wherein the encapsulation process comprises dipping the concentric winding portions into an encapsulating material.  
     
     
         15 . The inductive coil of  claim 12  wherein the encapsulation process further comprises centrifuging the dipped concentric winding portions.  
     
     
         16 . The inductive coil of  claim 12  wherein the encapsulation material is introduced between the winding portions after the winding portions are coupled together.