Abstract:
A stator comprises a cavity formed into the insulator of the windings. The non-wound wire sections that extend from the windings and the electrical conductors attached thereto are housed within the cavity. A cap locks onto the stator insulator and prevents the non-wound sections of wire from migrating out of the cavity.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       APPENDIX 
       [0003]    Not Applicable. 
       BACKGROUND OF THE INVENTION 
       [0004]    1. Field of the Invention 
         [0005]    This invention pertains generally to electric motors and generators. More specifically, this invention pertains to stators wherein the non-wound sections of wire that lead from the windings are retained within a cavity formed in the stator. 
         [0006]    2. General Background 
         [0007]    In most electric motors and generators, protecting and restraining the non-wound sections of wire that extend from and are formed integrally with the windings is important. This is particularly the case with stators of the type found in direct drive laundry washing machines. Prior art methods of restraining such wires, the electrical conductors that are attached thereto, and the junctions between them include the use of numerous cable ties to secure the wires and connectors tightly against the stator body. However, such cable ties are time consuming to install and can result in inconsistencies between assembled stators. Still further, such prior art methods do not protect the wires, conductors, and junctions from abrading against foreign object debris or against other components that move, vibrate, or rotate relative to the stator. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention provides stators with an efficient means for retaining and protecting the non-wound sections of wire, electrical conductors, and the junctions therebetween. Such components are retained within a cavity that is formed in the stator and that is capped in a manner that retains and protects the components. 
         [0009]    In one aspect of the invention, a stator comprises a core formed of ferromagnetic material. The core has a plurality of teeth arranged circumferentially about an axis. The stator also comprises a plurality of wire coils. Each of the wire coils is wound around a respective one of the core&#39;s teeth. The stator further comprises at least two non-wound sections of wire that extend from the plurality of wound wire coils, and at least two electrical conductors. Each of the electrical conductors is electrically connected to a respective one of the non-wound sections of wire in a manner forming an electrical junction. Still further, the stator comprises first and second retaining members that are secured to each other. The first and second retaining members substantially enclose a cavity that extends circumferentially about a substantial portion of the core. The cavity houses at least a portion of the non-wound sections of wire. 
         [0010]    In another aspect of the invention, a stator comprises a core formed of ferromagnetic material. The core has a plurality of teeth arranged circumferentially about an axis. The stator also comprises a plurality of wire coils. Each of the wire coils is wound around a respective one of the stator&#39;s teeth. The stator further comprises at least two non-wound sections of wire that extend from the plurality of wire coils, and at least two electrical conductors. Each of the electrical conductors is joined to a respective one of the non-wound sections of wire in manner forming an electrical junction. Still further, the stator comprises a cavity and a cap. The cavity extends at least partially around the axis in an arcuate manner. The non-wound sections of wire and the electrical junctions are positioned in the cavity. The electrical conductors extend out of the cavity. The cap extends at least partially around the axis in an arcuate manner and is secured to the cavity in a manner that prevents the non-wound sections of wire from migrating out of the cavity. 
         [0011]    In yet another aspect of the invention, a stator comprises a core formed of ferromagnetic material. The core has a plurality of teeth arranged circumferentially about an axis. The stator also comprises an electrical insulator that has a plurality of teeth arranged circumferentially about the axis. The teeth of the electrical insulator are aligned with the teeth of the core. The stator further comprises a plurality of wire coils. Each of the wire coils is wound around a respective one of the teeth and a corresponding one of the teeth of the electrical insulator. Still further, the stator comprises at least two non-wound sections of wire that extend from the plurality of wound wire coils, and at least two electrical conductors. Each of the electrical conductors is electrically connected to a respective one of the non-wound sections of wire in a manner forming an electrical junction. The electrical conductors are secured to the electrical insulator in a manner such that forces acting on portions of the electrical conductors cannot be transferred to the electrical junctions. 
         [0012]    In still another aspect of the invention, a method of assembling a stator comprises attaching a stator insulator to a stator core. The stator core has a plurality of teeth formed of ferromagnetic material that are arranged circumferentially about an axis. The stator insulator comprises a cavity. The method also comprises winding wire around the teeth of the stator core in a manner forming a plurality of wire coils that are each wound about a respective one of the teeth of the stator core, and in a manner forming a least two non-wound sections of wire that extend from the wire coils. The method further comprises attaching each of at least two electrical conductors to a respective one of the non-wound sections of wire in manner forming an electrical junction, routing the non-wound sections of wire and the electrical conductors in the cavity of the stator insulator, and attaching a cap to the stator insulator in a manner such that the non-wound sections of wire are retained between the cap and the stator insulator. 
         [0013]    Further features and advantages of the present invention, as well as the operation of the invention, are described in detail below with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a perspective view of an embodiment of a stator in accordance with the invention. 
           [0015]      FIG. 2  is a perspective view of the stator of  FIG. 1  with its cap omitted. 
           [0016]      FIG. 3  is a bottom perspective view of the stator of  FIG. 1 . 
           [0017]      FIG. 4  is a perspective exploded view of the insulator components of the stator of  FIG. 1 . 
           [0018]      FIG. 5  is a detail perspective view of the lower insulator component by itself showing the cable tie fitting on the bottom thereof. 
           [0019]      FIG. 6  is a perspective view of the cap of the stator by itself. 
           [0020]      FIG. 7  is a bottom perspective view of the cap of  FIG. 5 . 
           [0021]      FIG. 8  is a detail bottom perspective view of the cap of  FIG. 5 . 
           [0022]      FIG. 9  is a perspective view of the stator core. 
           [0023]      FIG. 10  is a perspective view of a second embodiment of a stator in accordance with the invention. 
       
    
    
       [0024]    Reference numerals in the written specification and in the drawing figures indicate corresponding items. 
       DETAILED DESCRIPTION 
       [0025]    An exemplary embodiment of a stator, generally indicated by reference numeral  20 , in accordance with the invention is shown in  FIGS. 1 ,  2 , and  3 . The stator  20  comprises a core  22 , first and second stator insulator components  24 , windings  26 , and a cap  28 . The core  22  is formed of a ferromagnetic material and comprises a core of laminations (individual laminations not shown). As shown most clearly in  FIG. 9 , the core  22  forms an annular ring around a central axis and comprises a plurality of teeth  30  that extend radially outward from the central axis. 
         [0026]    The stator insulator components  24  electrically insulate the teeth  30  of the core  22  from the windings  26 . Like the core  22  itself, each of the insulator components  24  forms an annular ring around the central axis and comprises a plurality of teeth  32  that extend radially outward from the ring. The core  22  is sandwiched between the insulator components  24 . The teeth  32  of the two insulator components  24  engage each other in a manner encircling each of the teeth  30  of the core  22 . The upper insulator component  24  comprises an annular channel  34  that extends between an upwardly protruding rim  36  and a plurality of upwardly protruding tabs  38  that are circumferentially spaced from each other about the annular ring. The rim  36  extends in generally an arcuate manner and comprises several snap-lock recesses or openings  40 . A recess  42  extends downwardly though the upper insulator component  24  and into lower insulator component from the channel  34  along one side of the stator  20 . A vertical slit  44  extends through the insulator components into the recess  42 . The slit extends  44  to an opening  45  (see  FIG. 5 ) in the lower insulator component  24 . As detailed in  FIG. 5 , a cable tie fitting  46  is formed in the lower insulator component  24  adjacent the opening  45 . 
         [0027]    The cap  28  forms an annular ring and, as shown in  FIGS. 6 and 7 , comprises several locking tabs  48  and biasing protrusions  50 . The cap  28  is dimensioned to cover the channel  34  of the upper insulator component  24 . When assembled to the upper insulator component  24 , the locking tabs  48  of the cap  28  cooperate with the snap-lock openings  40  on the rim  36  of the upper insulator component  24  in a manner that automatically locks the cap to the upper insulator component. However, prior to this locking action, the biasing protrusions  50  of the cap  28  engage the rim  36  of the upper insulator component and must be resiliently deflected in order to engage the locking tabs  48  with the snap-lock openings  40 . As such, after the cap  28  is locked to the upper insulator component  24  via the locking tabs  48  and the snap-lock openings  40 , the biasing protrusions  50  create a biasing force that eliminates any slack between the cap and insulator component to prevent the cap from rattling against the insulator component. 
         [0028]    The stator  22  is assembled by first sandwiching the stator core  22  between the insulator components  24 . Thereafter, wire is wound about each of the teeth  30  of the core  22  to form the windings  26 . It should be appreciated that the wire is wound also around each of the teeth  32  of the insulator components  24 , forming wire coils, such that the wire coils do not directly contact the core  22 . After forming the windings  26 , several non-wound sections of wire  52  ( FIG. 2 ), extend from the windings and are routed in the channel  34  of upper insulator component  24 . The free end of each of these non-wound sections of wire  52  is then attached to the end of an electrical conductor, such as a sheathed electrical conductor  54 , in a manner forming an electrical junction  56  between the non-wound sections of wire and the electrical conductor. Other electrical conductors, such as terminals, are also contemplated as being within the scope of the invention. The electrical conductors  54  are then slipped through the slit  44  formed in the insulator components  24  and into the recess  42 . Portions of the electrical conductors  54  extend out of the opening  45  of the lower insulator component  24 . In the exemplary embodiment depicted here, the distance in which the electrical conductors  54  extend into the stator  20  is short enough so that the junctions  56  between the non-wound sections of wire  52  and electrical conductors are positioned in the recess  42  of the insulator components  24 . The electrical conductors  54  are then bent over against the cable tie fitting  46  and a cable tie  58  is placed around the fitting and the electrical conductors in a manner securing them together (see  FIG. 3 ). The assembly of the stator  20  is completed by attaching the cap  28  to the upper insulator component  24  in the manner described above. 
         [0029]    As assembled, the cap  28 , the channel  34 , and the recess  42  define the bounds of a cavity that captures the non-wound sections of wire  52  and the junctions  56 . Trapped in the cavity, the non-wound sections of wire  52  and junctions  56  are protected and can not migrate into nearby rotating objects. Thus, the insulting components  24  and the cap  28  collectively act as retaining members for retaining the unwound section of the wire coils  52  and the junctions  56 . 
         [0030]    A second embodiment of a stator  60  in accordance with the invention is shown in  FIG. 10 . The second stator  60  is identical to the stator  20  described above, with a few exceptions. Unlike the first stator  20 , the upper insulator of the second stator  60  is formed by a plurality of insulating components  24   a ,  24   b ,  24   c  that each form third of a ring. Collectively, the plurality of insulating components  24   a ,  24   b ,  24   c  function in the same manner as the upper insulating component  24  of the first stator  20 . Similarly, the second stator  60  comprises a plurality of caps  28   a ,  28   b ,  28   c ,  28   d ,  28   e  that are each snapped to one of the upper insulating components  24   a ,  24   b ,  24   c . Unlike the cap  28  of the first stator  20 , the caps  28   a ,  28   b ,  28   c ,  28   d ,  28   e  of the second stator  60  do not form a ring. Nonetheless, the caps  28   a ,  28   b ,  28   c ,  28   d ,  28   e  of the second stator  60  are configured to retain the unwound sections of the windings in the channel formed by the of the upper insulating components  24   a ,  24   b ,  24   c . It should be appreciated that the number of insulating components and caps could be more or less than is shown in  FIG. 10 . It should also be appreciated that caps need not be equally spaced about the circumference of the stator. 
         [0031]    In view of the foregoing, it should be appreciated that the invention achieves the several advantages over prior art stators. 
         [0032]    As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by the above-described exemplary embodiment, but should be defined only in accordance with the following claims appended hereto and their equivalents. 
         [0033]    It should also be understood that when introducing elements of the present invention in the claims or in the above description of exemplary embodiments of the invention, the terms “comprising,” “including,” and “having” are intended to be open-ended and mean that there may be additional elements other than the listed elements. Additionally, the term “portion” should be construed as meaning some or all of the item or element that it qualifies. Moreover, use of identifiers such as first, second, and third should not be construed in a manner imposing any relative position or time sequence between limitations. Still further, the order in which the steps of any method claim that follows are presented should not be construed in a manner limiting the order in which such steps must be performed.