Abstract:
An improved armature construction in which a coil winding wiring board and cooperating insulator around which the coils are wound at least in part wherein the insulator and wiring board are interconnected by an attachment arrangement that automatically positions and retained components in the desired circumferential, axial and radial positions.

Description:
BACKGROUND OF INVENTION 
   This invention relates to a rotating electrical machine and more particularly to an improved armature construction for such machines. 
   As is well known, most armatures for rotating electrical machines be they either motors or generators consist of a core made of a ferromagnetic material and generally laminated in construction. The core defines a plurality of radially extending pole teeth around which electrical coils are wound. Generally these windings surround an insulating bobbin arrangement. In addition the armature includes a wiring base to which the ends of the coil windings ate attached to provide the external electrical connection for the machine. Thus there are a number of separate components that must be fixed together. 
   In addition to the establishment of the connection of the various elements it also is important to insure their correct axial, radial and circumferential relationship. U.S. Letters Pat. No. 6,566,779, issued May 20, 2003 and assigned to the assignee hereof and Japanese Published Application, publication number 2002-58228, which represents an improvement in the structure shown in that patent and its Japanese priority application, illustrate a construction in which a wiring base of a three layer constitution placed on the axial end of the armature of a rotary electric machine. Like the other and above described prior art, the armature comprises a laminated core comprised of a circular portion from which a plurality of magnetic pole teeth extend radially. A two part bobbin made of insulating resin attached to the core and has portions that encircle each of the magnetic pole teeth. 
   In accordance with that patent and the published Japanese application, the bobbin is provided with a stopper for attaching the wiring base. The stopper is made of a metallic plate that projects outward from the bobbin and is bent toward the wiring base to form an L shape. The wiring base comprised of three layers for three phases of U, V, and W and is of an annular shape. It also has a plurality of engaging holes arranged in a circular row near its periphery that receive the stopper. Parts of the stoppers project out of the engaging hole. The wiring base is fixed to the remainder of the armature by depositing a solder mass on the projecting ends of the stopper. 
   Although effective, this attachment method is labor intensive. In addition, the shape, dimension and axial, circumferential and radial positioning may vary unacceptably. 
   It is therefore a principal object of this invention to provide an improved armature structure. 
   It is a further object of this invention to provide an improved attachment method for the wiring base that is simpler, less labor intensive and more accurate. 
   SUMMARY OF INVENTION 
   This invention is adapted to be embodied in an armature construction for a rotating electrical machine comprised of a core consisting of a plurality of laminated plates having a circular member from which a plurality of pole teeth radially extend A pair of insulators are positioned on opposite axial sides of the core and having tooth engaging portions encircling the pole teeth to receive coil windings. 
   A wiring base is positioned on one axial side of one of the insulators. The wiring base is made from an insulating material and is adapted to receive the wire ends of the coil windings. Interconnecting members are formed on the one insulator and the wiring base for connecting the wiring base in a predetermined axial, radial and circumferential position 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  is an exploded, perspective view of an armature constructed in accordance with the invention. 
       FIG. 2  is an enlarged perspective view of the wiring base. 
       FIG. 3  is a further enlarged view of the area encompassed by the circle  3  in  FIG. 2 . 
       FIG. 4  is a further enlarged view of the area encompassed by the circle  4  in  FIG. 2 . 
       FIG. 5  is an enlarged perspective view of one of the bobbin halves. 
       FIG. 6  is a further enlarged view of the area encompassed by the circle  6  in  FIG. 5 . 
       FIG. 7  is a side elevational view of the wiring base. 
       FIG. 8  is an elevational view of the wiring base showing the side opposite that shown in  FIG. 7 . 
       FIG. 9  is a cross sectional view of the wiring base. 
       FIG. 10  is an enlarged view looking in the direction of the arrow  10  in  FIG. 9  and showing the attachment hook. 
       FIG. 11  is a cross sectional view of the hook. 
       FIG. 12  is an enlarged view showing one of the terminal ends. 
       FIG. 13  is a view looking in the direction of the arrow  13  in  FIG. 12 . 
       FIG. 14  is a view looking in the direction of the arrow  14  in  FIG. 12 . 
       FIG. 15  is a side elevational view of one of the bobbin halves. 
       FIG. 16  is a side elevational view of the other side of the one of the bobbin halves. 
       FIG. 17  is an enlarged side view of the portion of the one bobbin halve showing the attachment portion thereof. 
       FIG. 18  is an enlarged cross sectional view taken along the line  18 - 18  in  FIG. 17 . 
       FIG. 19  is a side elevational view of the wound armature. 
       FIG. 20  is a cross sectional view of the wound armature and attached circuit board molded into a case for an electrical machine. 
       FIG. 21  is an end elevational view of the molded case. 
       FIG. 22  is a cross sectional view of a completed machine embodying the invention. 
       FIG. 23  is an end elevational view of the machine. 
       FIG. 24  is a view showing the machine wiring. 
       FIG. 25  is a wiring diagram of the machine. 
   

   DETAILED DESCRIPTION 
   Referring now in detail to the drawings and initially to  FIG. 1 , the reference numeral  31  indicates generally an armature of a rotary electric machine embodying to this invention. As illustrated the armature  31  is specifically utilized as an armature for a 3-phase motor, although those skilled in the art will readily understand that it can be utilized with other types of motors or generators. It is comprised of a wound core, indicated generally at  32 , and a wiring base  33  acting as a coil end circuit fixed in a manner to be described to one axial end (top end side in the  FIG. 1 ) of the wound core  32 . 
   The wound core  32  is comprised of a core yoke, indicated generally at  34 , made as a body of laminated thin plates, upper and lower bobbin half insulators  35 , and coils  36  (See  FIG. 19 ) wound on the wound core yoke  34  around the insulators  35 . The core yoke  34  has a ring shape portion, indicated at  37 , from which in this embodiment, extend radially inwardly a plurality of circumferentially spaced magnetic pole teeth  38  so as to surround the periphery of a rotor  36  ( FIGS. 22 and 23 ). 
   Slots  39  are formed between adjacent magnetic pole teeth  38 . The faces of the insulators  35  are integrally formed with insertion lugs  41  of the same number as the slots  39  so that when the ring-like insulator  35  are inserted upward and downward into the slots  39  both insulators  35  are circumferentially secured and held to the core yoke  34  in the desired circumferential relation. As will be described later again, coil wire is wound up and down over the insulators  35  through the slots  39  located on both sides of each magnetic pole tooth  38 , so that plural coils  36  ( FIG. 19 ) are arranged in a circular row. 
   The wiring base  33  is attached to the top surface of the wound core  32 , in a manner to be described, and is shown best in  FIGS. 2-4 . The wiring base  33  is of a three layer construction made up of ring-like, phase-specific terminal members  42  (See  FIG. 9 ) corresponding to three phases of U, V, and W placed one over another in the axial direction and insulated from each other. The phase-specific terminal members  42  are made into a single body by insert mold forming with a resin material. As shown in  FIG. 2 , the wiring base  33  is of a ring shape (C shape) made as a single body with a molded resin  43 . 
   Each phase-specific terminal member  42  has plural terminal lugs  44  projecting radially outward for connecting a winding head or winding tail of each winding end portion  33  of the coil  36  of each phase. The terminal lug  44  has its tip bent as shown in the enlarged view  FIG. 4  so that a worker can easily tie and hold the winding end portion around the terminal lug  44  when the coil winding end is to be connected. Continuing to refer to  FIG. 4  and as will be described in more detail later, the reference numeral  45  denotes for a soldering-purpose bend for clinching and soldering the winding end, and a bend  46  for retaining the winding end from coming off. 
   Each phase-specific terminal member  42  also has an integrally formed external connection terminal  47  corresponding to each of the three phases of U, V, and W. As shown in  FIG. 2 , the external connection terminal  47  is formed to project from axially one side face of the wiring base  33  toward the opposite side of the wound core  32  by bending part of the phase-specific terminal member or by initially punch-raising from the main part of the member when it is formed. 
   The periphery of the wiring base  33  has integrally formed plural (two at diametrically opposite positions in the example illustrated) hooks  48  serving as secure-holding means to properly position the wiring base  33  relative to the insulator  35  when fitted into the wound core  32  and to secure the wiring base  33  to the wound core  32 . The shape of the hooks is best shown in the perspective view  FIG. 3 . As seen there the hook  48  is formed in a triangular shape, projecting down from the end face of the wiring base  33  to be elastically, radially deformable. The tip of the hook  48  is formed with a barb  49  that projects radially inward. 
   The configuration and construction of the insulator  35  to accommodate and make the connection to the wiring base  33  will now be described with reference primarily to  FIGS. 5 and 6 . The insulator  35  is formed like the core yoke  34  in a ring shape. Formed on its axial periphery are a plurality of winding receivers, indicated generally at  51  in the same number ( 18 ) as the pole teeth  36  for engage-stopping the coil winding end. Each winding receiver  51  is formed with a cut  52  through which the winding end of the coil is led radially outwardly of the insulator  35 . 
   The insulator  35  is also formed integrally with plural winding portions  53  that extend radially inward from the winding receivers  51 . The winding portions  53  are aligned with the magnetic pole teeth  38  ( FIG. 1 ) of the core yoke  34  by the pole teeth  38  being fitted into recesses  54  formed on the side of the insulator  35  adjacent the core yoke which embrace the pole teeth  38 . The slots  39  are formed between adjacent winding portions  53 . The aforementioned insertion lugs  41  are formed under the winding portions  53  in the area between them. Each winding portion  53  has on its radially inner side a curved flange  55  for supporting and retaining the inside of each coil. 
   The winding of the coil  36  is retained at one end by the inside round portion of the flange  55 . Incidentally, the winding comprises the part of the coil  36 , formed by winding a wire passing through the slot  39  ( FIG. 1 ) up and down around the magnetic pole tooth  38 . The coil winding is held and supported between the flange  55  formed on the inside round surface side of both the upper and lower insulators  35  and the winding receiver  51 . An annular projection  56  ( FIG. 2 ) on the underside of the wiring base  33  is engaged with a back surface  55   a  of the flange  55  supporting the coil end. In this way, the insulators  35  and the wiring base  33  are held in the same radial position. 
   The round periphery of the insulator  35  is further formed integrally with a plurality of circumferentially spaced hook receivers  57  equal in number and spacing to the number and spacing of the hooks  48  for receiving the hooks  48  of the wiring base  33 . Thus in this embodiment the hook receivers  57  are diametrically positioned. 
   These hook receivers  57  are shown best in  FIG. 6 . The hook receivers  57  are formed like the winding receiver  51  to project upward from the end face of the insulator  35 . The hook receivers have a round periphery side formed with a recess  58  to receive the hook  48 . The recess  58  is triangular so as to be generally complementary to the hook  48 . The end of the recess  58  is formed with a projection  59  for engaging with the barb  49  formed at the tip of the hook  48 . The hook receiver  57  is also provided with a cut  61 , next to the recess  58 , for passing the wiring end of the coil  36 . Each hook  48  is capable of elastically bending about a center specifically the connection point between the hook  48  and the main part of the molded resin  43 . When the hook  48  engages with the hook receiver  57 , the tip of the hook  48  slightly deflects radially outward and then the barb  49  snap-engages with the projection  59  of the hook receiver  57 . 
   Referring now to  FIGS. 7 and 8 , these show respectively the outer and inner faces of the wiring base  33 . As seen in these figures, the terminal lugs  44  are formed to project radially outward from and spaced along the round periphery of the molded resin  43  of the wiring base. The three external connection terminals  47  project from positions different in both radial and circumferential locations on the wiring base  33 . 
   The inside round surface of the molded resin  43  is provided with plural, circumferentially spaced axial grooves  62 . These grooves  62  are recesses, formed by projections formed on the side of a metallic mold, for radially positioning (centering) all the ring-like phase-specific terminal members  42  as seen in  FIG. 6  positioned at three different levels. The molded resin  43  is provided with an opening  63  to clear a magnetic pole position detector  64  ( FIG. 23 ) made up of a Hall element and others components for detecting the rotary position of a cooperating rotor. 
   As previously mentioned and as best seen in  FIGS. 2 and 8 , an annular (C shape in this embodiment) projection  56  is formed along the inside round surface of the underside of the wiring base  33 . The annular projection  56  is for locating the wiring base  33  and the insulators  35  on a common axis as the annular projection  56  fits in tight contact with the back surface  55   a  (radially outer side) of each flange  55  while the hook  48  engages with the hook receiver  57  at the time of attaching the wiring base  33  to the insulators  35  which are integral with the wound core  32 . 
   Referring now to  FIG. 6  the three ring-like, phase-specific terminal members  42  are embedded in the molded resin  43 , at three levels in the axial direction, corresponding to the three phases of U, V, and W, in the wiring base  33 . As shown, part of the topmost phase-specific terminal member  42  bends upward and projects out of the molded resin  43  to serve as the external connection terminal  47 . Although not shown, parts of other phase-specific terminal members  42  also bend likewise to serve as the rest of the external connection terminals  47 . Incidentally, the terminal lugs  44  are not shown in this figure. 
     FIGS. 12-14  show the appearance of the terminal lug  44  projecting on the periphery of the wiring base  33 . As is clear from these views and  FIG. 4 , the terminal lug  44  is made by punching a metallic sheet followed by bending, with its tip having the two bends  45  and  46 . The bend  45  is formed by bending back in a V shape to serve as a soldering terminal for clinching and fusing the coil winding end portion, indicated as  65 . The other bend  46  is made by bending an end portion upright to serve as a holding lug for preventing the winding end portion  65  clinched with the fusing terminal (bend  45 ) from coming off the V-shape opening of the bend  45 . In this way, a worker, before connecting the winding end portion to the terminal lug  44 , can easily engage-stop the winding end portion with the terminal lug  44  by twining the winding end portion around the bend  45 . In other words, the winding end portion  65 , in reference to  FIG. 12 , at first in the state of projecting on the unseen side of the terminal lug  44 , is then pulled up (as seen in the figure), passed through a recess  66  of the molded resin  43  and taken up to the visible side of the terminal lug  44 , routed around through the gap between the molded resin  42  and the bend  45  toward the V opening, drawn deep into the V space and out to be caught with the top end side of the holding bend  46  as seen in  FIG. 13 ). The winding end portion is applied with soldering in the state of being clinched and held with the soldering bend  45 , so that the winding end  65  is joined to the terminal lug  44 . 
   Referring now to  FIGS. 15 and 16 ,  FIG. 15  shows that the winding portions  53  ( 18  in the illustrated embodiment) are equally circumferentially spaced. It also shows that insertion lugs  41  are formed on the reverse side of the insulator  35  in a circumferential alignment with the slots  39  formed among the winding portions  53 . It also shows, as described before, that the two hook receivers  57  are diametrically spaced. 
     FIGS. 17 and 18  also shows the hook receiver  57  portion of the insulator  35 , enlarged. As shown in  FIG. 17 , the outside wall bottom edge  67  of the insertion lug  41  is slightly tapered from the horizontal. In this way, the insertion lug  41  is shaped to project in one direction (downward in  FIG. 17 ) from the end face of the insulator, with a corner  68  serving as a leading tip, so as to be easily inserted into the slot  39  of the core yoke  34 . 
   As seen in  FIG. 18 , the hook receiver  57  of the insulator  35  has the projection  59  for engage-stopping the barb  49  of the hook  48 . The projection  59  is formed in the shape of wedge or triangle in cross section so as to stop the axial movement of the wiring base  33  and prevent it from coming off the insulator  35  once the projection  59  engages with the hook  48  of the wiring base  33 . 
   As described above, this embodiment is arranged that, when the wiring base  33  is fitted to the insulators  35  to make a unitary body, the wiring base  33  is axially positioned automatically relative to the insulators  35  as the hooks  48  are fitted to the two hook receivers  57 , and the wiring base  33  is also positioned automatically in the circumferential direction. Moreover, because of the presence of the hooks  48  and the hook receivers  57 , axial alignment (centering) of the both components is accomplished at the same time, so that the wiring base  33  is automatically positioned also in the radial direction relative to the insulators  35 . The radial positioning is effected as described above mainly by fitting the annular projection  56  ( FIG. 2 ) provided on the underside of the wiring base  33  onto the back surface  55 a of the inside round surface flange  55  of the insulator  35 . In this way, providing both of the insulator  35  and the wiring base  33  respectively with the hook  48  and the hook receiver  57  facilitates the positioning work which has so far been complicated, and improves its accuracy without requiring other positioning jigs. 
   Referring now to  FIG. 19 , this shows the wiring base  33  attached to the wound core  32 . As seen from the figure, the coils  36  are wound on the  18  magnetic pole teeth  38  of the wound core  32 . These coils  36  are interconnected through the wiring base  33  which serves as the coil end circuit mentioned before. Crossover lines  69  interconnect the desired coils  36  without the intervention of the terminal lugs  44  of the wiring base  33 . Thus, coils are interconnected as will be described later by reference to  FIGS. 24 and 25 . 
   How the aforedescribed assembly can be incorporated into a rotating electrical machine such as an electric motor will now be described by reference to  FIGS. 20-24 . Referring first to  FIGS. 20 and 21 , the wiring base  33  and connected wound core  32  are made into a single body using a molded resin  71  to form a single body motor case, indicated generally at  72 . To carry out this mold forming, the wound core  32  together with the wiring base  33  are placed in a mold (not shown). As resin material is poured into the mold cavity, the single body, the motor case  72  including the wound core, is formed. The motor case  72  formed in the mold as described above has three external connection terminals  47  projecting from its underside as seen in  FIG. 21 . 
   Screw receivers  73  are for attaching the motor end plate which is not shown. Also projections  74  are provided on the sides of the opening  63  as aforenoted for attaching a magnetic pole position detecting base  75  shown in  FIG. 23 . 
   Referring now to  FIGS. 22 and 23 , these show a rotor unit  76  is fitted in the motor case  72 . The rotor unit  76  is installed in the motor case  72  with a rotor shaft  77  as the motor output shaft projecting from the motor case  72 . The magnetic pole position detecting base  75  has mounted on it a Hall element  76  for detecting rotary magnetic pole position of the rotor unit  76 . Finally permanent magnets  78  are attached to the outer surface of the rotor unit  76 . 
   Referring now to the wiring diagram of the armature  31  in  FIG. 24  the showing winding head and winding tail of the coils of the phases U, V, and W. A winding end  65  of a specific coil is connected to the terminal lug  44  of the wiring base  33 . The winding ends of the coils connected to the respective terminal lugs  44  are connected through the phase-specific terminal members  42  embedded in three layers in the wiring base  33 . 
     FIG. 25  is a simplified view of the circuit of the connecting construction shown in  FIG. 24 . This embodiment shows a three-coil-series, two-parallel connection, with each phase formed with six coils, with two coil sets in parallel, each set having three coils in series. The phases U, V, and W shown in the figure are connected to the external connection terminals  47  of the wiring base  33 . 
   Thus it should be apparent from the foregoing description that providing the means for defining the position of the wiring base in the axial, radial, and circumferential directions relative to the insulator of the wound core to which the wiring base is fitted makes it possible to attach and secure the wiring base to the wound core through the insulator while accomplishing proper positional relationship between the wiring base and the insulator without using an auxiliary equipment such as a positioning jig. Of course those skilled in the art will readily understand that the described embodiment is only exemplary of form that the invention may take and that various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.