Heating oven for dynamo-electric machine component manufacture

Abstract

A heating oven for use in dynamo-electric machine component manufacture is provided. The oven uses forced air heating to raise the temperature of in-process component subassemblies to suitable process temperatures. The heating oven includes a rotating drum mounted in a cabinet. A number of open-ended tubular cradles are disposed in circular arrays between the drum faces. Batches of component subassemblies may be individually loaded into the cradles for heat treatment. Air flow channels are set up in the oven cabinet to evenly distribute heated air through individual cradles. Heated air after passing over the individual in-process subassemblies, exits the cradles through side slots in the cradle walls into the interior of the drum. The exiting air is reheated and recirculated through the heating oven.

1 - 30 . (canceled)  
   
   
       31 . A method for heat treatment of dynamo-electrical machine components, comprising: 
 loading said dynamo-electrical machine components in cradles disposed on a movable structure, wherein each of said cradles comprises a cavity having an air-flow inlet opening and an air-flow outlet opening; and    directing heated air through said cavities over said dynamo-electrical machine components loaded in said cradles along flow paths which enter said cavities through said inlet openings and exit said cavities through said air-exit openings.    
   
   
       32 . The method of  claim 31  wherein said directing heated air through said cavities further comprises using a common manifold to distribute heated air from a heated-air source to said cavities.  
   
   
       33 . The method of  claim 31  wherein said directing heated air through said cavities further comprises using air-injection nozzles.  
   
   
       34 . The method of  claim 31  wherein said directing heated air through said cavities further comprises intermittently injecting air through said cavities.  
   
   
       35 . The method of  claim 31  wherein said directing heated air through said cavities comprises establishing a pressure gradient across said cavities.  
   
   
       36 . The method of  claim 31  wherein said directing heated air further comprises using a common low-pressure region to draw air out of said cavities.  
   
   
       37 . The method of  claim 31  wherein said directing heated air further comprises collecting air exiting from said cavities using a conduit.  
   
   
       38 . The method of  claim 31  wherein said directing heated air further comprises recirculating air exiting from said cavities through an air heater.  
   
   
       39 . The method of  claim 31  further comprising using a fan to draw air from an air-heater by suction and to force said drawn air through said cavities.  
   
   
       40 . The method of  claim 31  wherein said moveable structure is disposed in a cabinet, further comprising using a fan whose outlet is connect to said cabinet to draw heated air from an air-heater and using said fan to force the drawn heated air into said cabinet.  
   
   
       41 . The method of  claim 40  wherein said using said fan to force the drawn heated air into said cabinet further comprises using a manifold disposed on said cabinet to distribute the heated air into said cabinet.  
   
   
       42 . The method of  claim 40  further comprising drawing air exiting said cavities through said outlet openings out of said cabinet.  
   
   
       43 . The method of  claim 42  further comprises reheating said air drawn out of said cabinet and recirculating said reheated air through said cabinet.  
   
   
       44 . The method of  claim 42  wherein said moveable structure is a rotating structure mounted on an hollow axial shaft which is open to the interior of said rotating structure, wherein said cavity outlet openings lead to the interior of said rotating structure, and wherein said drawing air exiting said cavities through said outlet openings out of said cabinet further comprises drawing air out of said cabinet through said hollow axial shaft.  
   
   
       45 . The method of  claim 40  further comprising using a first baffle in said cabinet to direct heated air entering said cabinet to said cavity inlet openings.  
   
   
       46 . The method of  claim 40  further comprising using a second baffle in said cabinet to reduce dead space in the flow of said heated air through said cabinet.  
   
   
       47 . A method for heat treatment of dynamo-electrical machine components, comprising: 
 providing a cabinet comprising a front cover; a back wall; a central support structure; and a side wall;    disposing a drum in said cabinet, wherein said drum comprises: a front plate; a back plate; cylindrical side walls; and a hollow axial shaft, wherein said hollow axial shaft is attached to said back plate, is open to the interior of said drum, and is rotatably mounted in said central support structure;    disposing a plurality of open-ended tubular cradles in the interior of said drum between said front plate and said back plate such that the open ends of said tubular cradles are aligned with flow openings in said front and back plates, wherein said tubular cradles comprise slots connecting the interior of said tubular cradles to the interior of said drum;    connecting an outlet of an air-recirculating unit which includes an air heater to said cabinet; and    using said air-recirculation unit to force heated air through said cabinet.    
   
   
       48 . The method of  claim 47  further comprising disposing said air-recirculation unit within said hollow axial shaft.  
   
   
       49 . The method of  claim 47  wherein said connecting the outlet of an air-recirculating unit to said cabinet further comprises using a manifold disposed on said cabinet to distribute air into said cabinet.  
   
   
       50 . The method of  claim 47  wherein said using said air recirculation unit further comprises using a first baffle to direct a portion of heated air flow received into said cabinet to said flow openings in said back plate, and to direct another portion of said received heated air flow to said flow openings in said front plate.  
   
   
       51 . The method of  claim 47  further comprising attaching an inlet of said air-recirculating unit to said hollow axial shaft, and using a suction force of said air-recirculating unit to draw air exiting said tubular cradles via said slots into said hollow axial shaft through the interior of said drum.  
   
   
       52 . The method of  claim 51  further comprising using said air heater to reheat said air drawn into said hollow axial shaft.  
   
   
       53 . The method of  claim 47  wherein using said air-recirculation unit further comprises using a second baffle to reduce air flow dead space in said cabinet.