Abstract:
An electrical device includes a plurality of stacked laminates that form a tubular stator portion, a cooling passage partially defined by orifices formed in the plurality of stacked laminates, a housing including a cavity further defining the cooling passage, the cooling passage defining a fluid flow path parallel to a rotational axis of the stator portion, a sump portion communicative with the cooling passage, the sump portion including a cavity defined by the stator portion and the housing member.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/346,964, filed May 21, 2010. 
    
    
     BACKGROUND OF THE INVENTION 
     Electric machines such as alternators typically utilize stators that have a plurality of slots therein within which conductive windings are positioned. Current flowing through the windings during operation of the machine generates magnetic fields that facilitate the machine&#39;s conversion of mechanical energy into electrical energy or vice versa. The operation of an electric machine often increases the temperature of the stator. Temperature is a cause of operational concern for electrical machines as it reduces performance during operation and over a longer term reduces machine life. In view hereof, assemblies and methods that tend to reduce operating temperatures of electric machines are well received by the art. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In an exemplary embodiment an electrical device includes a plurality of stacked laminates that form a tubular stator portion, a cooling passage partially defined by orifices formed in the plurality of stacked laminates, a housing including a cavity further defining the cooling passage, the cooling passage defining a fluid flow path parallel to an axis of the stator portion, a sump portion communicative with the cooling passage, the sump portion including a cavity defined by the stator portion and the housing member. 
     In another exemplary embodiment an electrical device includes a plurality of stacked laminates that form a tubular stator portion, a cooling passage partially defined by orifices formed in the plurality of stacked laminates, a housing including a cavity further defining the cooling passage, the cooling passage defining a fluid flow path that is aligned radially relative to an axis of the stator portion, a sump portion communicative with the cooling passage, the sump portion including a cavity defined by the stator portion and the housing member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
         FIG. 1  depicts a partial perspective view of a stator assembly disclosed herein; 
         FIG. 2  depicts a partial perspective view of an alternate embodiment of a stator assembly disclosed herein; 
         FIG. 3  depicts a partial perspective view of another alternate embodiment of a stator assembly disclosed herein; 
         FIG. 4  depicts a partial perspective view of yet another alternate embodiment of a stator assembly disclosed herein; 
         FIG. 5  depicts a perspective view of an exemplary embodiment of an electrical device assembly disclosed herein; 
         FIG. 6  illustrates a front view of the electrical device assembly of  FIG. 5 ; and 
         FIG. 7  illustrates a side partially cut-away view of the electrical device assembly of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A detailed description of an embodiment of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
       FIG. 1  illustrates a portion of an exemplary embodiment of a stator assembly  10 . The assembly  10  includes a stator  12  having a tubular body with a plurality of slots  14 . The stator  12  is constructed from a plurality of stacked and attached laminations  16 . The illustrated assembly includes a plurality of cooling passages  18 . The illustrated cooling passages  18  are shown with examples of a variety of shapes and profiles including, for example, circular shaped, star shaped, oval shaped, and crescent shaped. In operation, a cooling fluid flows through the cooling passages  18  and cools that stator  12 . 
     In fabrication, the laminations  16  are cut or stamped into the stator shape from a metallic sheet material. The stamping and cutting of the laminations into the stator shape includes the stamping or cutting of the cooling passages  18  in the laminations by forming orifices in the laminations  16 . Thus, the stator shape and the cooling passages  18  may be stamped or cut in a single step, or in multiple steps. Once the stator laminations  16  are fabricated, the laminations  16  are stacked in a desired order, the orifices are aligned to form cooling passages  18 , and the laminations  16  are attached together to form the stator  12  having the cooling passages  18 . One exemplary method for attaching the laminations  16  is to apply an adhesive to the metallic sheet material prior to the fabrication of the laminations  16 . Once cut and stacked, heat and pressure may be applied to the laminations  16  to activate the adhesive and bond the laminations  16  together. 
       FIG. 2  illustrates an alternate exemplary embodiment of a stator assembly  20 . The stator assembly  20  includes a stator  22  having cooling passages  18 . In the stator assembly  20 , the cooling passages  18  include portions that are orientated parallel to axis  21 . The cooling passages  18  include curved portions  24  that connect the parallel portions. Cooling fluid may flow parallel and substantially perpendicular to the axis  21  along a fluid flow path indicated by the arrows  25  and defined by the cooling passages  18 . The curved portions  24  of the cooling passages  18  and the cooling passages  18  of  FIG. 2  may be formed in a similar manner as the cooling passages  18  of  FIG. 1  above by, for example, stamping or cutting the laminations  16  to form the curved portions  24 . 
       FIG. 3  illustrates an alternate exemplary embodiment of a stator assembly  30 . The stator assembly  30  is similar to the stator assembly  20  (of  FIG. 2 ) described above, however the curved portions  34  of the cooling passages  18  are formed in a housing portion  35  that is fastened to the stator  32 . 
       FIG. 4  illustrates another alternate exemplary embodiment of a stator assembly  40 . The stator assembly  40  includes laminations  16  and is fabricated in a similar manner as described above. The stator assembly  40  includes cooling passages  41  that are orientated substantially radially relative to axis  42 . A radial line relative to the axis  42  is illustrated by the line  47 . The flow of fluid is illustrated by the arrows  43 . The illustrated embodiment includes ports  44  that are disposed on the arcuate outer radial surface  49  of the stator assembly  40 . The cooling passages  45  are similar to the cooling passages  41  and include ports  46  that are disposed on the planar surface  48  of the stator assembly  40 . The stator assembly  40  may include any combination of ports  46  and  44  that may be located on the outer radial surface  49  or the planar surface  48  of the stator assembly  40 . In alternate embodiments, ports  46  may be located on the planar surface (not shown) opposing the planar surface  48 . 
       FIG. 5  illustrates a perspective view of an exemplary embodiment of an electrical device assembly (device)  50  that includes a stator  12 . The electrical device assembly  50  may be operated as, for example, a motor, alternator, or generator device. The stator  12  is shown for illustrative purposes, however any of the stator assemblies described above may be similarly disposed in the device  50 . The motor assembly  50  includes housing portions  35  that may be fastened to the stator  12 . 
       FIG. 6  illustrates a front view of the motor assembly  50  with a housing portion  35  removed. The device  50  includes a sump portion  60  that includes cavities  61  defined by portions of the stator  12  and the housing portions  35 . In the illustrated embodiment the sump portion  60  is arranged as an extension from the stator portion  40 . The sump portion  60  is formed in the laminations  16  using a similar process as described above to form the cooling passages  45  (of  FIG. 4 ). The sum may be used to retain and cool cooling lubricant that flows through the cooling passages  45  of the stator assembly  40 . The sump portion  60  is sized and arranged to hold a sufficient amount of cooling lubricant to cool the stator assembly  40 . The amount of cooling lubricant may, for example, depend on the amount of heat that is desired to be removed from the stator assembly  40 . A rotor assembly  62  is disposed in the device  50 . The rotor assembly  62  is aligned coaxially with the stator  12  and is operative to rotate relative to the stator  12 . 
       FIG. 7  illustrates a side cross-sectional view of the device  50  that includes the cooling passages  18 . 
     While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims.