Abstract:
A method is provided for producing a distributed wave winding. To accelerate the currently used method for producing a distributed wave winding the invention provides for a relative indexing to be carried out between the template and coil receiver after a concentric coil group has been ejected and for a further concentric coil group of the same phase with a connection to previous coil group to be wound on the template and ejected in the coil receiver.

Description:
RELATIONSHIP TO OTHER APPLICATIONS 
     This is a division of application Ser. No. 09/508,186 filed on Mar. 8, 2000 now U.S. Pat. No. 6,601,286. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a method for producing a distributed wave winding for electric motors or generators, especially those with a high number of poles. 
     BACKGROUND OF THE INVENTION 
     In simple undistributed wave windings (see European Patent Disclosure EP 0 226 550 B1, FIG.  1 ), each phase is a single wave-like coil group, which then when inserted in the stator has the same number of windings in the stator slots as in the stator winding heads. This has the disadvantage that when three phases are placed in the stator, crossings are created that unnecessarily enlarge the winding head, and aside from other disadvantages in particular prevent a high fill factor from being attained. For this reason, a so-called distributed winding is as a rule preferred, in which the wire portions located in a slot of the stator are partly in one circumferential direction and partly in the other on each end face of the stator (see German patent disclosure DE 29 21 114, FIG.  2 ). Thus the winding heads of one phase are distributed, and together with the other identically disposed phases, they form a relatively narrow winding head. 
     If the wave winding, for instance according to German Patent Disclosures DE 23 51 952 B2 or DE 31 20 865 A1, is prewound essentially in a round form and then deformed into a star-like or wave-shaped cross section and then inserted, then while double-layered wave windings can still be made, nevertheless the two layers cannot be wound in succession without an interruption in the wire; instead, after the insertion, which results in the situation shown in German Patent DE 35 22 085 C2, they have to be joined together by a so-called circuit interconnection. 
     Finally, from German Patent DE 42 44 488 C1, it is also already known to create concentric wave-like windings by means of a winding nozzle that revolves relative to a fixed template and to make a distributed winding as described, without any interruption in the wire. However, this is feasible only with the aid of a complicated wire length pulling device, not shown in the reference. This is because when a second coil group begins to be wound, it is necessary for the end of the first coil group that has already been ejected to be held using a wire length pulling device. 
     In this method, aside from the complicated wire length pulling device required, there is the disadvantage that a revolving winding nozzle winds the coils. As a result, at most two parallel winding wires can be processed. This restriction is due to the fact that the revolving winding nozzle is a flyer with multiple deflections of the winding wire. 
     Particularly for generators, it is necessary to produce a plurality of parallel windings, that is, more than two such parallel windings; thus the known device runs up against its limits, since even with doubly parallel windings, crossings in the flyer and on the template occur that affect the insertion and the distribution in the winding head. 
     SUMMARY OF THE INVENTION 
     It is therefore the object of the invention to create a method of the type defined at the outset and a device suitable for performing the method, which with a short cycle time make it possible to produce a distributed winding with a circuit interconnection between the coil groups and the processing of a plurality of parallel wires. 
     The above object is attained according to the invention in that after the transfer of a concentric coil group a relative indexing takes place between a template and a coil receiver, and after that a further concentric coil group of the same phase with a connection to the previous coil group is wound onto the template and transferred into the coil receiver. 
     The invention offers the advantage that the beginning of winding of the second coil group takes place without a complicated wire length pulling device, since the end of the first coil group after the ejection extends obliquely over one flank of a cam of the template, so that when the second coil group begins to be wound, the winding wire is carried along by the template. In certain cases, especially with relatively thin wires, it is necessary for a holding-down device to restrain the already-wound first coil group in the coil receiver and keep it in position, so that when the second coil group begins to be wound, the winding wire will be drawn not from the coil receiver but only from the wire guide nozzle. 
     Another advantage is that a plurality of parallel wires—at present, four parallel wires—that are required for the stators of generators can be processed without creating crossings between the individual wires, since the individual wires from wire supply barrels are guided directly via a wire guide nozzle onto the template. The invention also makes it possible to process a multiple of the four parallel wires required in the present instance. 
     The invention is also designed such that one phase can be distributed over more than two coil groups. This can mean that one phase is distributed over six coil groups, for example. In this example, this does lengthen the cycle time, but a better winding head distribution on the stator is achieved. This still changes nothing in the inventive concept that the six coil groups are wound with a circuit interconnection. This is attained in that in the winding of each further coil group, the template and the coil receiver rotate synchronously, and accordingly so do the various wound coil groups that are deposited in the coil receiver. The synchronous rotation is effected by means of a slaving rod that comes from the middle of the template and is coupled into the insertion star and set jointly into rotation by a template drive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be described in further detail below in terms of exemplary embodiments shown in the drawing. Shown are: 
     FIG. 1, a winding device for a wave winding, and a coil receiver with a coil group; 
     FIG. 2, a device identical to FIG. 1 but with two coil groups; 
     FIG. 3, a cross section through FIG. 1; 
     FIG. 4, a cross section through FIG. 2; 
     FIG. 5, a pattern diagram of two coil groups. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG.  1  and FIG. 2, in a longitudinal section, show one embodiment of the invention, whose winding principle has already been described in detail in German Patent Disclosure DE 0S 43 06 624. The winder  10  comprises a template  12  and forming elements  14 ,  16  and  18 , which are embodied rotatably about a common axis  20  through a motor, not otherwise shown, and a wire guide nozzle  22 , which is disposed in stationary fashion. A slaving rod  32  rotatable synchronously with the template  12  is disposed on the axis  20 , which is capable of making a positive connection with a coil receiver  38 . Secured to the slaving rod  32  is a cam  34 , which controls a holding-down device  36 . 
     In this example, the coil receiver  38  comprises individual insertion laminations  40  disposed in a circle, between which slots are formed which receive the fully wound coils. A insertion star  44  is disposed at the center of the insertion laminations  40  and can be coupled to the slaving rod  32 . The complete coil receiver  38  is rotatably supported by a bearing  46  relative to a housing, not shown, and can be indexed by a drive motor  48  into a different rotary angle position relative to the template  12 . It is also possible for the indexing of the coil receiver  38  to be done via the slaving rod  32 . 
     FIG. 1 shows a first already-wound coil group  50  that has been ejected from the template  12  into the coil receiver and has a circuit interconnection  56  to the wire guide nozzle  22 . 
     FIG. 2 shows the same view as FIG. 1, but with a second coil group  54 ; the interconnection  52  is automatically integrated between the two coil groups  50  and  54  when the winding of the second coil group  54  begins, without forming an unnecessary length. 
     FIGS. 3 and 4 show a cross section through FIGS. 1 and 2, respectively, and in detail show that a cutting knife  24  and a wire delivery head  26  are disposed between the wire guide nozzle  22  and the template  12 , and this delivery head delivers the beginning  28  of a winding wire to a clamping device  30  on the template  12 . 
     In this example, the template  12  comprises six outward-pointing cams, and the forming elements  14 ,  16  and  18  comprise six inward-pointing cams. The forming elements  14 ,  16  and  18  are controlled by a cam path, not shown—as already described in DE-OS 43 06 624. Another factor is that the forming elements  16  and  18  are also radially freely controllable by separate drives, not shown. 
     FIG. 3 shows the beginning  28  of the winding wire and the end  56  of the first coil group  50 . 
     FIG. 4 shows the end  56  of the first coil group  50 , which lies against a template cam and at the same time is the beginning for the second coil group  54 , and the end  58  of the second coil group  54 . 
     FIG. 5 shows only the wound pattern diagram of the coil groups  50  and  54 ; for the sake of clearer explanation, the first coil group  50  is shown complete, while only half of the second coil group  54  is shown. 
     From FIG. 5, the aforementioned stated object of the invention can be described in greater detail. If as is already known only the first—wave winding—coil group  50  were wound and inserted into a stator, then the winding heads would have the same number of windings as the wires present in a slot. 
     If the so-called “distributed winding” is wound, however, by dividing the number of windings of one phase in half, and if the first coil group  50  is wound with half of the windings and then with the circuit interconnection the second coil group  54  is wound with the second half of the windings, the result after the insertion of this phase into the slots is the required number of wires, but the windings are distributed half to each of the winding heads. This has the advantage that the winding heads are not so thick as in a single wave winding, and it has an even stronger effect if three phases are inserted into one stator. 
     The mode of operation of the method and device of the invention can now be described in further detail. 
     FIG. 3 shows the beginning  28  of the winding wire that leads through the wire guide nozzle  22  to the wire guide head  26 . By means of a drive, not shown, the wire guide head  26  moves along with the beginning  28  of the wire and guides it to the template  12  and transfers it to the clamping device  30 . Next, the template  12  rotates clockwise together with the forming elements  14 ,  16  and  18  and winds half of the required windings for one phase onto the first coil group  50 . Once the first coil group  50  has been wound, its end  56  initially terminates as shown in FIG.  3 . Next, only the forming element  16  moves radially forward to the center into its final position and places the end over the insertion laminations  40 . The first coil group  50  has thus been wound, and the template  12  can dip into the coil receiver  38 , and the coil group  50  is ejected from the template  12  by means of ejectors  60 . 
     To wind the second coil group  54 , the template  12  must move out of the coil receiver  38  as far as the winding position, just above the insertion laminations  40 , so that then by means of the drive motor  48  the coil receiver  38  can be indexed relative to the template  12  by the distance between two successive poles. 
     In this example, it is 30° counterclockwise, so that the end  56  is placed as seen in FIG.  4 . This end  56  is now the beginning for the second coil group  54  and now leads obliquely from the coil receiver  38  to the wire guide nozzle  22 , as seen in FIG.  1 . For the sake of better slaving of the winding wire as the winding is begun, the template  12  can be lowered to above the first coil group  50 , into the range of the insertion laminations  40 ; the forming elements  14 ,  16  and  18  remain in their position above the insertion laminations  40 . 
     Since this oblique wire guidance also extends over one flank of a cam of the template  12 , it is now simple, as the winding of the second coil group  54  begins, for the winding wire to be slaved by the template  12 . 
     Before the winding, however, the slaving rod  32  first moves into the insertion star  44 , where it is coupled with positive engagement, so that it rotates the coil receiver  38  synchronously when the template  12  rotates. A synchronous rotation of the coil receiver  38  together with the template  12  can also take place when the first coil group  50  is being wound. Before the second coil group  54  is wound, it is necessary in some cases for a holding-down device  36  to hold the already-wound first coil group  50  back in the coil receiver  38  and keep it in position, so that when the winding of the second coil group  54  begins, the winding wire will not be drawn from the coil receiver  38  but rather only out of the wire guide nozzle  22 . The holding-down device  36 , which after the winding of the second coil group  54  is located between the first and second coil groups, is tuned away by means of a cam  34  about a pivot point  62  into an inner free space. This moving away of the holding-down device ( 36 ) is shown symbolically in FIGS. 1 and 2 on the left-hand side of the center line. A lifting unit  64  is controllable such that the first coil group  50  is held in a desired position below the upper edge of the insertion laminations  40  and holding-down device  36  in such a way that a secure beginning of winding of the second coil group  54  is assured. 
     As already noted, the end  56 , that is, the beginning of the second coil group  54  after the indexing of the coil receiver  38  is located as seen in FIG.  1  and FIG.  4 . The template  12  now rotates counterclockwise together with the coil receiver  38 , and as a result pulls the winding wire out of the wire guide nozzle  22  and deforms it to form the second wave-shaped coil group  54 . 
     After the winding, the end  58  of the second coil group  54  is located in front of the forming element  18 , as shown in FIG.  4 . The forming element  18  is now moved, by means of a drive not shown, radially toward the center into its end position, so that the end  58  is bent over the insertion laminations  40 . Thus the second coil group  54  is now fully wound as well. 
     Since this second coil group  54  is offset polewise from the first coil group  50  and was wound in the opposite direction, the result once the second coil group  54  has been ejected into the coil receiver  38  is a winding pattern as shown in FIG.  5 . As a result, the circuit interconnection  52  has automatically been integrated between the two coil groups  50  and  54  when the winding of the second coil group  54  was begun, without forming unnecessary length. Finally, once the end  58  has been cut with a cutting blade  24 , the slaving rod  32  has to move out of the coil receiver  38 . The coil receiver  38  can now circulate, for instance by means of a turntable, not shown, out of the winding position, and a new coil receiver can circulate into it. As the center rod  32  moves outward, the cam  34  is slaved at the same time, and as a result the holding-down device  36  is pivoted inward, so that it releases the coil groups. 
     It is also advantageous that with this device, a plurality of parallel wires can also be wound. 
     It is understood that innumerable further coil groups can follow, with a circuit interconnection to the previously wound ones. This is merely a matter of how the coil groups are designed in the stator. The more coil groups a phase is divided into, the better the distribution of the winding heads in the stator; but because of the frequent indexing of the template  12  relative to the coil receiver  38 , this has a negative effect on the cycle time.