Abstract:
Apparatus and method for winding coils of dynamoelectric machines, wherein a coil comprises members formed of leg portions ( 19   a,    190   a ). The leg portions ( 19   a,    190   a ) being inserted in slots ( 17, 170 ) of cores ( 18, 180 ) of the dynamo electric machine, wherein the slots ( 17, 170 ) are provided with insulation members ( 33, 330 ) for lining the walls of the slots ( 17, 170 ). The leg portions ( 19   a,    190   a ) are inserted in the slots ( 17, 170 ) of the cores ( 18, 180 ) of the dynamoelectric machines. A passage member ( 20, 200 ) having passages ( 22, 220 ) is provided aligned with a core ( 18 ,180 ) to align the passages ( 22, 220 ) with the slots ( 17, 170 ). The area ( 23, 230 ) adjacent an edge of a passage ( 22 ) is aligned with the end ( 32, 320 ) of an insulation member ( 33, 330 ) of a slot ( 17, 170 ) for engaging the end ( 32, 320 ) of the insulation member ( 33, 330 ) during insertion of the leg portions ( 19   a,    190   a ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to International Patent Application No. PCT/EP2014/071226, filed Oct. 3, 2014, and entitled “Apparatus and Method for Manufacturing Components of Dynamoelectric Machines,” which claims priority to Italian Patent Application No. PI2013A000092, filed Oct. 18, 2013, and entitled “Apparatus and Method for Manufacturing Components of Dynamoelectric Machines.” The present application incorporates herein by reference the disclosures of each of the above-referenced applications in their entireties. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to solutions for winding rotor cores or stator cores using coil members consisting of U shaped members, or other configurations, formed from a conductor strip. The conductor strip normally presents a copper core coated with insulation material. 
     In particular, the invention relates to a method and an apparatus for winding coils of dynamoelectric machines of the type mentioned above. 
     DESCRIPTION OF THE PRIOR ART 
     A U shaped member has leg portions, which are inserted in respective slots of a core and a head portion, which joins the two leg portions. More particularly, the head portion remains outside of the slots and functions as an electrical connection portion between the leg portions. The leg portions form the magnetic field in the final dynamoelectric machine. These U shaped members are often referred to as hairpins, according to the terminology of the field. 
     An initial operation provides that a plurality of hairpins can be assembled together to form an entire coil assembly to be inserted in slots of the core. Successively, the core assembly is inserted in a core by aligning and inserting the leg portions in the slots. Alternatively, the U shaped members can be inserted singularly in the slots one after another to completely wind the cores. Apparatus and methods for performing the foregoing manufacturing stages have been described in GB644761. 
     Prior to inserting the leg portions in the cores, the slots are normally lined with insulation members to avoid direct contact of the conductor with the core material. The insulation members can be formed and inserted in the slots using solutions like those described in EP 1,061,635 
     Each insulation member is normally placed with portions that extend beyond the ends of the core by a predetermined distance. This distance guarantees required electrical insulation values of the completed core with respect to the coil conductors. 
     During insertion of the leg portions in the cores, the insulation members may be damaged or moved in the slot due to a pushing action that the conductor exerts on the surfaces of the insulation members. More particularly, when the leg portions are required to tightly fit in the available space of the slots to achieve a high slot fill, the insulation members is considerably pushed and may, as a result, be caused to move along the slots in the insertion direction. This unwanted movement causes a wrong positioning of the insulation member, and thereby causes serious malfunction problems. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to accomplish insertion of the leg portions of a coil in the slots of dynamoelectric machine without encountering the foregoing inconveniences of the prior art. 
     It is also an object of the invention to provide solutions for producing cores of dynamoelectric machine having high slot fill when leg portions of a coil need to inserted in the slots. 
     These and other objects are achieved by the apparatus of independent apparatus claim  1 . 
     According to another aspect of the invention a method for winding coils of a dynamoelectric machine is described in independent method claim  9 . 
     Other characteristics of the invention are described in the dependent claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be now illustrated with the following description of an exemplary embodiment thereof, exemplifying but not limitative, with reference to the attached drawings in which: 
         FIG. 1  is a prospective view illustrating a coil assembly aligned with a rotor core in an operating stage of the invention; 
         FIG. 2  is a prospective view illustrating a coil assembly aligned with a stator core in an operating stage of the invention; 
         FIG. 3  is a plan view of the apparatus of the invention from a direction  3  of  FIGS. 1 and 2  without showing the stator core or the rotor core for reasons of clarity; 
         FIG. 4  is a partial view similar to the view of  FIG. 3 , although as seen from an observer viewing from the opposite side of the sheet containing  FIG. 3 .  FIG. 4  illustrates a core where the leg portions have been inserted in the slots according to the principles of the invention; 
         FIG. 5  is a partial section view as seen from directions  5 - 5  of  FIG. 4 ; 
         FIG. 6  is a view similar to the view of  FIG. 3  illustrating a second embodiment of the invention; 
         FIG. 7  is a partial view similar to the view of  FIG. 6 , although as seen from an observer viewing from the opposite side of the sheet containing  FIG. 6 .  FIG. 7  illustrates a core where the leg portions have been inserted in the slots according to the principles of the invention. 
         FIG. 8  is a partial section view from directions  8 - 8  of  FIG. 7 ; 
         FIG. 9  is a view similar to the view of  FIG. 8 , although illustrating an alternative solution of the invention for processing a core; 
         FIG. 10  is a view similar to the view of  FIG. 8 , although illustrating a second alternative solution of the invention for processing a core; 
         FIG. 11  is an elevation view of an apparatus of the invention; 
         FIG. 12  is an enlarged view of a portion of  FIG. 11 ; 
         FIG. 13  is a view of a portion of the apparatus of  FIG. 11  in an operating stage of the invention; 
         FIG. 14  is an elevation view as seen from direction  14  of  FIG. 1 ; 
         FIG. 15  is a plan view, similar to the view of  FIG. 3 , as seen from direction  15  of  FIG. 14 , where certain parts have been omitted for reasons of clarity. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a coil assembly  19  aligned with slots  17  of a rotor core  18 . Insulation members  33  line the slots  17  and protrude from the ends  18 ′ of rotor core  18 , as shown in  FIG. 1 . Passage member  22 , which will be described more in detail in the following, is centred around the central axis  150  of rotor core  18  and on one side of one of rotor core end  18 ′, as shown in  FIG. 1 . The coil assembly  19  is held by a holding unit to result centred on the central axis  150  of rotor core  18 . The holding unit has been omitted in  FIG. 1  for reasons of clarity, although it is shown in  FIGS. 14 and 15  where it is referenced with the number  140 . The holding unit  140  holds coil assembly  19  so that leg portions  19   a  are aligned with respective slots  17 . The holding unit  140  is moved towards rotor core  18  to insert the leg portions  19   a  in the respective slots  17 . Column members  50 , which engage the external surface of the rotor core  18  to centre the rotor core on the central axis  150  (see  FIG. 15 ). 
       FIG. 2  illustrates a solution similar to that of  FIG. 1 , but for inserting a coil assembly  190  in the slots of a stator core  180 . More particularly, coil assembly  190  is aligned with slots  170  of stator core  180 . 
     Insulation members  33  line the slots  170  and protrude from the ends of the stator core, as shown in  FIG. 2 . Passage member  22  is also provided centred with respect to central axis  150 ′ of stator core  180  and on one side of a stator core end  180 ′, as shown in  FIGS. 2 and 3 . The coil assembly  190  is held by a holding unit similar to that of  FIGS. 14 and 15 , and is centred on the central axis  150 ′ of stator core  180 . The holding unit holds coil assembly  190  so that leg portions  190   a  are aligned with respective slots  170 . The holding unit is moved towards stator core  180  to insert the leg portions  190   a  in the respective slots  170 . Column members  500 , which engage the external surface of the stator core  180 , centre the stator core with respect to the central axis  150 ′. 
     With reference to  FIG. 3 , passage member  20  is provided with a plurality of passages  22 . According to the embodiment of  FIG. 3 , passages  22  are configured to have a narrower central portion, which forms two support areas  23  that are portions of the area adjacent to the edge of passages  22 . More particularly, support areas  23  can be the ends of protuberances which extend inside passages  22 , like is shown in  FIGS. 3, 4 and 5 . 
       FIGS. 3, 4 and 5  illustrate the application of passage member  20  for the insertion of insulation members in the core  18  of a rotor. It should be appreciated that the principles described with reference to  FIGS. 3 , and  5  can be equally applied for the insertion of insulation members  330  in the core  180  of a stator. 
     Passages  22  are positioned around central axis  20 ′ of passage member  20  at equal angular distances from each other, like is shown in  FIG. 3 . The radial distance of the passages  22  from central axis  20 ′ and the angular position of the passages  22  around central axis  20 ′ is such that that passages  22  will be aligned with respective slots  17  or  170 , respectively of the rotor core  18  or the stator core  180  that needs to be processed. 
       FIGS. 4 and 5  illustrate a situation where the rotor core  18  rests on support members  21 , and with slots  17  of the rotor core  18  aligned with passages  22 . In the case of processing a stator core, the latter can rest on support members  210 , and slots  170  of the stator core  180  will be aligned with passages  22 . 
       FIGS. 4 and 5  also show that leg portions  19   a  are inserted in a slot  17  lined with insulation member  33 . The leg portions  19   a  are moved in insertion direction  34  to be inserted in the slots  33 . Insertion direction  34  can be parallel to central axis  20 ′ of passage member  20 , once passage member  20  has been aligned with slots  17  by centring of the rotor core on behalf of column members  50  and the use of an index tooth that will be more fully described in the following. 
     As shown in  FIGS. 4 and 5 , an end  32  of insulation member  33  engages with the support areas  23  of passage member  20  during insertion of leg portions  19   a  in slots  17 . 
     The engagement of the end  32  of insulation member  33  against support areas  23  avoids that insulation member  33  moves in the insertion direction  34  during the insertion of leg portions  19   a.  In  FIG. 4 , the portions of the end  32  of the insulation member  33 , which engage support areas  23 , are shown with dashed line representation.  FIG. 4  also shows the sharpened ends  19   a′  of leg portions  19   a,  which favour the insertion of leg portions  19   a  in slots  17 . 
     In the situation of  FIGS. 4 and 5 , the insulation member  33  of slots  17  has been flared, i.e. enlarged so in such a way to form a cone, in order to form an enlarged portion  33 ′ on the side where the leg portions  19   a  start to enter the slots  17  during the insertion movement. The enlarged portion  33 ′ avoids forcing of the leg portions  19   a  when entering the slots  17 , and also acts as a stop member to prevent movement of the insulation members  33  along slots  17  during the insertion of coil assembly  19 . 
       FIGS. 6, 7 and 8  relate to an embodiment of the invention where an enlarged portion  33 ′ of the insulation member  33  has also been provided on the side of the rotor core  18 , or of stator core  180 , which is opposite to the side where the leg portions  19   a  enter the slots during insertion, as shown in  FIG. 8  for a rotor core. Furthermore, with particular reference to  FIG. 6 , an alternative passage member  200  is foreseen having passages  220  which have a more extensive support area for the end  320  of an enlarged portion  33 ′ of an insulation member  33 . In this case the support area  230  for the end  320  of the enlarged portion  33 ′ may consist in the entire contour surrounding a passage  220 , like is shown in  FIGS. 6, 7 and 8 , to avoid movement of the insulation member  33  during the insertion of a coil assembly. 
     The situation of the end  320  of the insulation member being engaged along a continuous portion  230  surrounding a passage  220  of passage member  200  is shown with the dashed line representation in  FIG. 7 . 
     Although the figures show the areas as continuous surfaces, it is contemplated the possibility that the portions have a certain height and are distributed around the edges of the passages. 
       FIGS. 6-15  illustrate further principles of the invention applied for insertion of a coil assembly in the core  18  of a rotor. It should be noted that the principles described with reference to  FIGS. 6 - 15  can be equally applied to the insertion of insulation members  330  in the core  180  of a stator. 
       FIG. 9  illustrates a situation without the enlarged portion  33 ′ on the end of the rotor core  18  where the leg portions  19   a  enters during the insertion movement. This can be possible when the entrance stage of the leg portions  19   a  in slot  17  is not critical. 
       FIG. 10  illustrates a situation where the enlarged portions  33 ′ of the insulation member  33  have a fold to form supplementary insulation portions  36 , which are directed towards the rotor core ends  18 ′. In this case the ends  320  of the insulation member have double thickness, thereby resulting more stronger. 
       FIG. 11  illustrates an apparatus for producing the enlarged portions  33 ′. This apparatus comprises enlargement tools  40  assembled on a carrying member  41 . The enlargement tools  40  can be present in a number that is equal to the number of slots  17  of the rotor core where the insulation members  33  require the enlarged portions  33 ′. The enlargement tools  40  are provided with a cone portion  40   a  and a narrow portion  40   b,  see also  FIGS. 12 and 13 . Carrying member  41  can be heated by means of electrical resistance  43 . The heat developed by electrical resistance  43  is conducted through carrying member  41  and reaches each of enlargement tools  40 . To produce the enlarged portions  33 ′, each of the heated enlargement tools  40  can be aligned and inserted in a respective insulation member  33 , as shown in  FIG. 13  for one of the insulation members  33 . This can be achieved by centring and moving carrying member  41  with respect to the rotor core  18 , or with respect to the stator core  180  that is being processed. The heat present in enlargement tools  40  favours the bending of insulation member  33  to form the enlarged end  33 ′ as shown in  FIG. 13 . 
       FIG. 14  illustrates a coil assembly  19  aligned with core slots  17  of a rotor core  18 . The coil assembly is being held by holding unit  140 . Holding units capable of holding the coil assemblies  19  and  190  during insertions operations have been described in GB644761. 
     With reference to  FIG. 14 , the rotor core  18  is supported along central axis  150  by support members  21  or  210  of passage members  20  or  200  (see  FIGS. 3 and 6 ). 
     In  FIG. 14 , support members  21  or  210  of passage members  20  are hidden by insulation members  33  on the side  55  where the insulation members  33  reach engagement with passage member  20 . Column members  50  which engage the external surface of the rotor core  18  centre the rotor core on the central axis  150 , as shown in  FIG. 14 . A column member  50 , which is towards the viewer of  FIG. 14 , has been removed for reasons of clarity, see also  FIGS. 3 and 6 , where all the column members  50  are represented. 
     A column member  50  may be provided with an index tooth (not shown), which engages the sides of an opening  17 ′ of a rotor core slot  17 . The index tooth maintains the rotor angularly oriented around central axis  150  after placement of the rotor core  18  on support members  21 . A base member  160  is present in  FIG. 14  to support passage member  20  along the central axis  150 . Referring to  FIG. 14  the base member and the columns are supported by a carrier platform  270 . 
     As shown in  FIG. 15 , carrier platform  270  can move on rails  271  between position A and position B. In  FIG. 15 , rotor core  18  has been omitted, consequently passage member  20  and columns members  50  are visible. Position A can be the position of a station where a load/unload device places a rotor core to be processed on support members  21  (shown for example in  FIG. 3 ) in the correct angular positions around central axis  150  so that the index tooth of a column member  50  can be engaged. This will result in the slots  17  of the rotor core being in alignment with the passages  22  of passage member  20 , or with the passages  220  if using passage member  200 . In position A, the same load/unload device can also remove the rotor core  18  from plate member  20  or plate member  200  once the core assembly  19  has been inserted. 
     To accomplish that the rotor core receives coil assembly  19 , carrier platform  270  can be moved on rails  271  to reach position B where the insertion operation can be performed using holding unit  140 , like is shown in  FIGS. 7-10 and 14 . 
     Enlargement of the ends of the insulation members  33  to produce enlarged portions  33 ′, by using the principles described with reference to  FIG. 11- 13 , can occur in a manufacturing position which is upstream with respect to position A. 
     Although the figures show coils comprising U-shaped member, the principles according to the present invention can be adopted even for winding coils of dynamo electric machine formed with members having different configurations and comprising a leg portion. 
     The foregoing description of specific exemplary embodiments will so fully reveal the invention according to the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt in various applications the specific exemplary embodiments without further research and without parting from the invention, and, accordingly, it is meant that such adaptations and modifications will have to be considered as equivalent to the specific embodiments. The means and the materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. it is to be understood that the phraseology or terminology that is employed herein is for the purpose of description and not of limitation.