Stator of an electric motor

Abstract

A stator for an electric motor has a stator core, a winding and a housing enclosing the stator core and winding. The stator core has a yoke and a plurality of poles extending inwardly from the yoke. The winding formed by coils wound about the poles of the stator core. The housing grips the stator core and has at least one inwardly deformed portion that retains the stator core in the housing and prevents rotational movement of the stator core relative to the housing.

1 . A stator of an electric motor, comprising:
 a stator core comprising a yoke and a plurality of poles extending inwardly from the yoke;   a winding formed by coils wound about the poles of the stator core; and   a housing enclosing the stator core, wherein the housing grips the stator core and has at least one inwardly deformed portion that retains the stator core in the housing without rotational movement of the stator core relative to the housing.   
     
     
         2 . The stator of  claim 1 , wherein a number of recesses are formed in an outer surface of the yoke, and the at least one deformed portion comprises protrusions extending inwardly from an inner surface of the housing and engaging respective recesses. 
     
     
         3 . The stator of  claim 2 , wherein the stator core comprises a plurality of individual stator segments coupled to each other in a circumferential direction of the stator. 
     
     
         4 . The stator of  claim 3 , wherein each stator segment forms a respective one of the recesses. 
     
     
         5 . The stator of  claim 4 , wherein the recesses are slots, and the protrusions are continuous or discontinuous ridges. 
     
     
         6 . The stator of  claim 3 , wherein each stator segment comprises a plurality of laminations stacked together, each lamination comprises a rim section and a pole section extending inwardly from the rim section, the stacked rim sections forming a rim of the segment, the rims of adjacent segments being arranged to form the yoke of the stator core, and the stacked pole sections of each segment forming one of the poles of the stator core. 
     
     
         7 . The stator of  claim 6 , wherein each rim section has a notch in an outer edge thereof, the notches of each segment cooperatively forming one of the recesses of the yoke. 
     
     
         8 . The stator of  claim 3 , wherein an interlocking structure is formed between adjacent ends of adjacent segments. 
     
     
         9 . The stator of  claim 8 , wherein the interlocking structure comprises a coupling projection on one end of the rim of one segment and a coupling recess in the adjacent end of the rim of an adjacent segment, the coupling projection engaging with the coupling recess. 
     
     
         10 . A stator of an electric motor, comprising:
 a stator core comprising a plurality of individual segments each having a rim and a pole extending inwardly from the rim;   a winding formed by coils wound about the poles of the stator core; and   a housing enclosing and gripping the stator core,   wherein the housing has at least one inwardly deformed portion that retains the stator core in the housing without rotational movement of the stator core relative to the housing, the at least one inwardly deformed portion comprising at least one protrusion extending inwardly from an inner surface of the housing and at least one groove formed in an outer surface of the housing at a position corresponding to the at least one protrusion.   
     
     
         11 . The stator of  claim 10 , wherein the stator core comprises six segments and the winding comprises six coils each wound on a corresponding segment, the six coils being connected into 3 phases each having two coils connected in series, the two coils of each phase being wound on two segments which are arranged diametrically opposed. 
     
     
         12 . The stator of  claim 10 , wherein each segment forms a recess in an outer surface of the rim thereof, and the at least one deformed portion comprises a plurality of protrusions engaging respective recesses. 
     
     
         13 . The stator of  claim 12 , wherein the recesses are slots, and the protrusions are continuous ridges. 
     
     
         14 . The stator of  claim 12 , wherein the recesses are slots, and the protrusions are discontinuous ridges. 
     
     
         15 . The stator of  claim 10 , wherein an interlocking structure is formed between adjacent ends of the rims of adjacent segments. 
     
     
         16 . The stator of  claim 15 , wherein the interlocking structure comprises a coupling projection on one end of the rim of one segment and a coupling recess formed in the adjacent end of the rim of an adjacent segment, the coupling projection engaging with the coupling recess. 
     
     
         17 . The stator of  claim 10 , wherein the at least one groove has two opposite axial ends each of which is spaced from a corresponding one of two opposite axial ends of the housing.