Method and kit for improved distribution of cooling air in an electric machine

Abstract

Method and kit for retrofitting an electric machine to reduce temperature rise therein are provided. The method allows for removing an originally assembled coil support on a spider structure of the machine. The originally assembled coil support is configured to allow axial flow to cooling air from a plurality of cooling vents in the armature of the machine. The method further allows for mounting a new coil support on the spider structure. The new coil support is configured to provide axial and radial routing to cooling air passing from the plurality of cooling vents. The air routing provided by that new coil support enables reduction of temperature rise.

What is claim is:  
     
         1 . A method for retrofitting an electric machine to reduce temperature rise therein, said method comprising: 
 removing an originally assembled coil support on a spider structure of the machine, said originally assembled coil support configured to allow axial flow to cooling air from a plurality of cooling vents in the armature of the machine; and    mounting a new coil support on said spider structure, said new coil support configured to provide axial and radial routing to cooling air passing from said plurality of cooling vents, the air routing provided by said new coil support enabling said temperature rise reduction.    
     
     
         2 . The retrofitting method of  claim 1  wherein said removing step comprises machining the originally assembled coil support to provide on said spider structure a cylindrical surface configured to receive the new coil support.  
     
     
         3 . The retrofitting method of  claim 2  wherein the plurality of cooling vents is arranged on said armature to provide respective inner and outer circles of cooling vents and wherein air flow from said outer circle of cooling vents is radially deflected by an annular chamber in said new coil support.  
     
     
         4 . The retrofitting method of  claim 3  wherein air flow from said inner circle of cooling vents is allowed to axially continue through corresponding openings in said new coil support.  
     
     
         5 . The retrofitting method of  claim 4  further comprising heating said new coil support to provide sufficient clearance between a central bore in said new coil support and the receiving cylindrical surface on the spider structure.  
     
     
         6 . The retrofitting method of  claim 5  wherein upon cooling of said new coil support a sufficiently tight interference fit is provided between said bore and said receiving surface on the spider structure.  
     
     
         7 . A method for retrofitting an electric machine to reduce temperature rise therein, said method comprising: 
 modifying an originally assembled coil support on a spider structure of the machine to provide axial and radial routing to cooling air passing from a plurality of cooling vents in the armature of the machine, the air routing provided by said modified coil support enabling said temperature rise reduction.    
     
     
         8 . The retrofitting method of  claim 7  wherein said modifying step comprises removing an outer flange of said coil support.  
     
     
         9 . The retrofitting method of  claim 8  wherein said modifying step further comprises providing a ring affixable between the armature and the coil support.  
     
     
         10 . The retrofitting method of  claim 9  wherein the plurality of cooling vents is arranged on said armature to provide respective inner and outer circles of cooling vents and wherein air flow from said outer circle of cooling vents is radially deflected by an outer wall of said ring to a space previously occupied by said outer flange.  
     
     
         11 . The retrofitting method of  claim 10  wherein air flow from said inner circle of cooling vents continues axially unimpeded by way of an inner wall of said ring.  
     
     
         12 . A kit for retrofitting an electric machine to reduce temperature rise therein, said kit comprising: 
 a new coil support mountable on a receiving surface of a spider structure of the machine, said new coil support configured to provide axial and radial routing to cooling air passing from a plurality of cooling vents in the armature of the machine, said receiving surface having been cleared from an originally assembled coil support lacking said radial routing.    
     
     
         13 . The retrofit kit of  claim 12  wherein the plurality of cooling vents is arranged on said armature to provide an inner circle of cooling vents and an outer circle of cooling vents and wherein air flow from said outer circle of cooling vents is radially deflected by an annular chamber in said new coil support.  
     
     
         14 . The retrofit kit of  claim 13  wherein air flow from said inner circle of cooling vents is allowed to axially continue through corresponding openings in said new coil support.  
     
     
         15 . The retrofit kit of  claim 12  further comprising a tool configured to remove the originally assembled coil support on said spider structure.  
     
     
         16 . The retrofit kit of  claim 15  further comprising a heating tool configured to heat said new coil support to provide sufficient clearance between a central bore in said new coil support and the receiving cylindrical surface on the spider structure.  
     
     
         17 . The retrofit kit of  claim 16  wherein upon cooling of said new coil support a sufficiently tight interference fit is provided between said bore and said receiving surface on the spider structure.  
     
     
         18 . A kit for retrofitting an electric machine to reduce temperature rise therein, said kit comprising: 
 a modified coil support mountable on a receiving surface of a spider structure of the machine, said modified coil support configured to provide axial and radial routing to cooling air passing from a plurality of cooling vents in the armature of the machine, said modified coil support produced from an originally assembled coil support lacking said radial routing.    
     
     
         19 . The retrofit claim of  claim 18  further comprising a modifying tool configured to modify said originally assembled coil support and wherein said modifying tool comprises a cutting tool configured to remove an outer flange of said coil support.  
     
     
         20 . The retrofit kit of  claim 19  wherein said modifying tool further comprises an affixing tool configured to affix a ring between the armature and the coil support.  
     
     
         21 . The retrofit kit of  claim 20  wherein the plurality of cooling vents is arranged on said armature to provide respective inner and outer circles of cooling vents and wherein air flow from said outer circle of cooling vents is radially deflected by an outer wall of said ring to a space previously occupied by said outer flange.  
     
     
         22 . The retrofit kit of  claim 21  wherein air flow from said inner circle of cooling vents continues axially unimpeded by way of an inner wall of said ring.