Patent Publication Number: US-2021194307-A1

Title: Stator with offset pins for an electric machine

Description:
The invention relates to a stator with offset pins for an electric machine, in particular an electric motor. 
     BACKGROUND INFORMATION 
     Electric machines are generally known and are increasingly used as electric motors for driving vehicles. An electric machine consists of a stator and a rotor. 
     The stator comprises a plurality of slots, in which the windings are guided. The windings may be formed from insulated copper rods, as so-called pins. The rotor is located in the stator and is connected to a rotor shaft. 
     Such a pin, U pin, or hairpin motor is known, for example, from U.S. Pat. No. 9,136,738 B2. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The object of the present invention is to provide a stator with windings made from pins, which is easy to manufacture. 
     According to the invention a stator for an electric machine comprises a plurality of pins, which are arranged on concentric circles at different distances to a stator center in slots in the stator, and each concentric circle forms a layer, wherein in each case six pins in different layers are serially connected to one another and form a winding, a first pin of the winding is located in a first slot in the 6n-1 layer, wherein n is an integer, a second pin of the winding is located in a second slot in the 6n layer, wherein the second slot has a first radial distance to the first slot in a first circumferential direction of the stator, a third pin of the winding is located in the first slot in the 6n-2 layer, a fourth pin of the winding is located in the second slot in the 6n-3 layer, a fifth pin is located in the first slot in the 6n-5 layer, a sixth pin of the winding is located in the second slot in the 6n-4 layer. 
     A winding may thereby circulate repeatedly about the teeth. The layers may be numbered in ascending order from the outside inward to the stator center. The number zero does not belong to the mentioned integers. 
     A stator with the winding according to the invention may be easily produced and generates an efficient electromagnetic field. The connection types establish an electrically conductive connection between the pins in the slots. The connection type may be a welding of conductors to the pins, or the pins may already be designed as double pins, so-called U pins, and thus already establish a connection upon insertion into the stator. Furthermore, a welding of end sections of the pins bent toward one another also represents a connection type. 
     The stator may preferably have a first end face and a second end face, and the first pin and the second pin may be connected to one another on the second end face by means of a first connection type, the second pin and the third pin may be connected to one another on the first end face by means of a second connection type, the third pin and the fourth pin may be connected to one another on the second end face by means of a third connection type, the fourth pin and the fifth pin may be connected to one another on the first end face by means of a fourth connection type, the fifth pin and the sixth pin may be connected to one another on the second end face by means of a fifth connection type, wherein the first, second, third, fourth, and fifth connection types differ from one another. 
     The different connection types enable an improved manufacturing. An alternating location of the connection types on different end faces enables the efficient formation of a winding about the stator teeth lying between the slots. 
     Even connection types on the same end face of the stator may differ due to different bending directions of a pin foot inward or outward with respect to the stator. 
     The stator may additionally preferably have at least two windings, and at least the sixth pin in the second slot is connected to a seventh pin in the 6n-1 layer in a third slot by means of a sixth connection type. 
     A combination of the previously listed connection types on different end faces or the same end face of the stator is also possible. A simple and fast manufacturing is possible due to one same connection type on the same end faces and different connection types on different end faces of the stator. For example, the connection is established by a type of pre-bent pins, so-called double pins or also U pins, on one end face, and pins are welded to one another individually or one side of the double pin in each case is welded on another end face of the stator. The weld spots may contact the feet of the pins or double pins. 
     The pin at the beginning of a winding may preferably be an end pin, wherein the first end pin is configured as a single pin. A single pin is, for example, an I pin. 
     In one embodiment of the invention, the same first distance may lie between the third slot and the second slot as lies between the second slot and the first slot. 
     Additionally preferably, the stator may have a plurality of windings, which extend across the entire circumference of the stator and thereby form a partial coil. 
     The rotating field generated by such a winding has fewer disturbing harmonics and thus has fewer torque ripples and smaller torque fluctuations, and also better NVH properties. The windings have a symmetry which generates a uniform rotating field. 
     In one embodiment of the invention, the end pins at the beginning or end of a coil may be configured as single pins. A single pin is, for example, an I pin. 
     In another embodiment, one pin respectively from three partial coils may be connected to one another by means of a seventh connection type or an eighth connection type and form a coil ( 201 ,  202 ). These pins may be so-called end pins, because they mark the end of a partial coil. 
     The partial coils may preferably form six coils, and these may be assigned to three phases in such a way that in each case, the pins from two coils, which are assigned to a same phase, may be located in three adjacent slots. 
     One input of an end pin of two coils may additionally preferably be connected to one another in each case by means of a ninth connection type. 
     Preferably, one output of an end pin of the two coils may be connected to one another in each case, and the two coils may thus be switched in parallel and may, in particular, be assigned to one phase. 
     The ninth connection type may be established by a conductor applied to the pins or by a conducting ring. 
     The two coils may be connected in parallel and may additionally be supplied by a same phase. The parallel connection may be carried out by the paired connection of a first and seventh end pin or of a sixth and twelfth end pin. 
     Two coils in the same slots may be switched in parallel and supplied by one phase, so that a stator results with windings for a three-phase electric machine. 
     Furthermore, two phases may respectively have an approximately identical current and voltage curve, and thus a six-phase inverter may only control a three-phase motor. A current division of the switching elements is possible in the inverter using this arrangement. 
     The second connection type may preferably comprise a first double pin, which is formed from the second pin and the third pin, wherein the first double pin has two inwardly-bent pin feet with a weld point in each case, and bridges the first radial distance. 
     The double pin may consist of one rod, which is bent in such a way that two pins, a connection between these two pins on a first end, and pin feet on a second end result. 
     The double pin may be inserted into the stator from one end face and may be welded to the pin feet of another double pin on the other end face. 
     The first distance describes a number of slots to be bridged. The actual spatial distance to be bridged depends on the position of the pin in the layers, because the double pins connect different layers. 
     The fourth connection type may additionally preferably comprise a second double pin, which is formed from the fourth pin and the fifth pin, wherein the second double pin has two inwardly-bent pin feet with a weld point in each case, and bridges the first radial distance. 
     In one embodiment of the invention, the sixth connection type may comprise a third double pin, which is formed from the sixth pin and the seventh or ninth pin, wherein the third double pin has two outwardly-bent pin feet with a weld point in each case, and bridges the first radial distance. 
     The seventh connection type may preferably comprise a fourth double pin, which is formed from a second or fourth end pin and a third or fifth end pin, wherein the fourth double pin has two outwardly-bent pin feet with a weld point in each case, and bridges a second radial distance. 
     The eighth connection type may additionally preferably comprise a fifth double pin, which is formed from an eighth or tenth end pin and a ninth or eleventh end pin, wherein the fifth double pin has two inwardly-bent pin feet with a weld point in each case, and bridges a second radial distance. 
     In one embodiment of the invention, a first single pin may comprise a first end pin and have a pin foot bent in the clockwise direction with a weld point. 
     In another preferred embodiment of the invention, a second single pin may comprise a sixth end pin and have a pin foot bent in the counterclockwise direction with a weld point. 
     A third single pin may preferably comprise a seventh end pin and have a pin foot bent in the counterclockwise direction with a weld point. 
     A fourth single pin may additionally preferably comprise a twelfth end pin and have a pin foot bent in the clockwise direction with a weld point. 
     In one embodiment, the first connection type may be formed by a weld connection of a first weld point on the pin foot of the third double pin or of the fourth double pin or of the first single pin to a second weld point on the pin foot of the first double pin or of the fifth double pin or of the third single pin. 
     The third connection type may preferably be formed by a weld connection of a third weld point on the pin foot of the first double pin or of the fifth double pin to a fourth weld point on the pin foot of the second double pin. 
     The fifth connection type may additionally preferably be formed by a weld connection of a fifth weld point on the pin foot of the second double pin to a sixth weld point on the pin foot of the third double pin or of the fourth double pin or of the second single pin. 
     According to the invention, a vehicle has an electric machine with a stator according to one of the preferred embodiments. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a stator. 
         FIG. 2  shows a stator with six slots and six layers. 
         FIG. 3  shows a winding scheme of a first partial coil. 
         FIG. 4  shows a winding scheme of a second partial coil. 
         FIG. 5  shows a winding scheme of a third partial coil. 
         FIG. 6  shows a stator with three partial coils and their connection to one another and thus a first coil. 
         FIG. 7  shows a winding scheme of another first partial coil. 
         FIG. 8  shows a winding scheme of another second partial coil. 
         FIG. 9  shows a winding scheme of another third partial coil. 
         FIG. 10  shows a stator with three other partial coils and their connection to one another and thus a second coil. 
         FIG. 11  shows a stator with two coils consisting of three partial coils respectively. 
         FIG. 12  shows a stator with two other coils. 
         FIG. 13  shows a stator with two other coils. 
         FIG. 14  shows a stator with six coils. 
         FIG. 15  shows a winding scheme of a first coil. 
         FIG. 16  shows a winding scheme of a second coil. 
         FIG. 17  shows two single pins. 
         FIG. 18  shows two double pins. 
         FIG. 19  shows a first double pin. 
         FIG. 20  shows a second double pin. 
         FIG. 21  shows a third double pin. 
         FIG. 22  shows a fourth double pin. 
         FIG. 23  shows a fifth double pin. 
         FIG. 24  shows a vehicle with an electric machine, in particular an electric motor with a stator. 
     
    
    
       FIG. 1  shows a stator  1  with a plurality of slots  5  in which pins  2 ,  3  are guided. Stator  1  has a first end face  7  and a second end face  9  lying opposite. Naturally, a rotor is additionally necessary to operate an electric machine. 
       FIG. 2  shows a stator  1  with slots and pins on six layers, wherein only six slots  51 - 56  are depicted. Pins  21 - 28  are arranged in the slots by way of example. The pins lie adjacent to one another in one slot. In the example from  FIG. 2 , there is space in one slot for six adjacent pins. 
     The six pins within one slot thus lie on different concentric circles L 1 , L 2 , L 3 , L 4 , L 5 , L 6  around center M of the stator, which thus form individual layers. A first distance  11  lies between two respective slots and is identical between all slots shown in  FIG. 2 . 
       FIG. 3  shows stator  1  from  FIG. 2 . The pins are still arranged on concentric circles, thus layers, wherein the concentric circles are not marked for the sake of a better depiction.  FIG. 3  depicts which pins are serially connected to one another. A first end pin  21  is located in a first slot  51  in layer L 5 . This first pin  21  is connected to a second pin  22  in a second slot  52  by means of a first connection type  61 , depicted as a solid line. Second pin  22  is located in layer L 6 . A first distance  11 , which is equal to distance  11  from  FIG. 2 , lies between first slot  51  and second slot  52 . 
     Second pin  22  is connected to a third pin  23  in first slot  51  by means of a second connection type  62 , depicted as a dashed line. Third pin  23  lies in layer L 4  and in the same slot as first pin  21 . Third pin  23  is connected to a fourth pin  24  via a third connection type  63 , depicted as a densely dotted line. Fourth pin  24  lies in second slot  52 , thus the same slot as second pin  22 . Fourth pin  24  lies in layer L 3 . 
     Fourth pin  24  is connected to a fifth pin  25  in first slot  51  by means of a fourth connection type  64 , depicted as a loosely dashed line. Fifth pin  25  is located in turn in first slot  51 , thus in the same slot as first pin  21  and third pin  23 . Fifth pin  25  lies in layer L 1 . There is thus still space for two other pins in layers L 2  and L 3  between third pin  23  and fifth pin  25  in first slot  51 . In addition, there is still space in first slot  51  for a further pin in layer L 6 . Fifth pin  25  is connected to a sixth pin  26  via a fifth connection type  65 , depicted as a loosely dotted line. Sixth pin  26  lies in second slot  52 , thus the same slot as second pin  22  and fourth pin  24 . Sixth pin  26  lies in layer L 2 . There is thus still space for two other pins in layers L 4  and L 5  between second pin  22  and fourth pin  24  in second slot  52 . In addition, there is still space in second slot  52  for a further pin in layer L 1 . 
     The connection of the first, second, third, fourth, fifth, and sixth pins forms a first winding  41 . First pin  21  is simultaneously also a first end pin. This end pin  21  has an input  101  for connecting to an energy source, for example, an inverter. First end pin  21  is therefore only connected to one other pin, thus to second pin  22 . First end pin  21  may thus be configured as a so-called single pin or I pin. 
     Sixth pin  26  is connected to a seventh pin  27  in layer L 5  in a third slot  53  via a sixth connection type  66 , depicted as a dotted line. At seventh pin  27 , the previously-described serial connection of the consecutive pins in the stator begins again, wherein seventh pin  27  is similar to first pin  21  with an offset of the slot by 120 degrees. In contrast to first pin  21 , seventh pin  27  is not an end pin, as seventh pin  27  is connected to two other pins, thus to sixth pin  26  and to another pin in slot  54 , layer L 1 . 
     The serial connection of seventh pin  27  to other pins in slot  54  forms a second winding  42 . The first, second, third, fourth, and fifth connection types  61 - 65  between these pins is identical to the respective first, second, third, fourth, and fifth connection types  61 - 65  of the pins of first winding  41 . 
     The two windings  41 ,  42  are connected by sixth connection type  66 . Due to the continuation of the serial connection, a third winding  43  is formed in two other slots  55  and  56 . Windings  41 ,  42 ,  43  are each connected using sixth connection type  66 . Sixth connection type  66  between the respective windings is thus identical. The first, second, third, fourth, and fifth connection types  61 - 65  between the pins of third winding  43  are also identical to first, second, third, fourth, and fifth connection types  61 - 65  of first and second windings  41 ,  42 . 
     Due to the continuation of the serial connection, fourth winding  44  is formed in two other slots  57  and  58 . Windings  41 ,  42 ,  43 ,  44  are each connected using sixth connection type  66 . Sixth connection type  66  between the respective windings is thus identical. First, second, third, fourth, and fifth connection types  61 - 65  between the pins of fourth winding  44  are also identical to first, second, third, fourth, and fifth connection types  61 - 65  of first, second, and third windings  41 ,  42 ,  43 . 
     Four windings  41 ,  42 ,  43 ,  44  form a first partial coil by way of one circuit clockwise about stator  1 . First pin  21  additionally has an input  101  for connecting to an energy source. First pin  21  of winding  41  thus represents a first end pin. The partial coil ends with pin  28  of third winding  43 . Last pin  28  of third winding  43  thus represents a second end pin. Second end pin  28  has, however, in contrast to first end pin  21 , connections to two other pins, as is explained in connection to  FIG. 6 . 
       FIG. 4  shows stator  1  from  FIG. 3 , wherein six other slots  71 - 76  are shown, which are located directly adjacent to slots  51 - 56  from  FIG. 3 . Distance  11  has the same length as in  FIG. 3 . 
     Pins  21   a - 28   a  are connected in the same way as pins  21 - 28  of  FIG. 3 . Even the connection types are identical with  FIG. 3  and are clearly expressed by identical reference numerals. Windings  41   a ,  42   a ,  43   a  are formed in the same way as is described in  FIG. 3 , and connected clockwise to one another by sixth connection type  66 . 
     Three windings  41   a ,  42   a ,  43   a  form a second partial coil by way of one circuit about stator  1 . The partial coil begins with a pin  21   a , which is a third end pin. Third end pin  21   a  has, however, in contrast to first end pin  21 , connections to two other pins, as is explained in connection to  FIG. 6 . The partial coil ends with pin  28   a  of winding  43   a . Last pin  28   a  of winding  43   a  thus represents a fourth end pin  28   a.    
       FIG. 5  shows stator  1  from  FIGS. 3 and 4 , wherein six other slots  81 - 86  are shown, which are located directly adjacent to slots  71 - 76  from  FIG. 4 . Distance  11  has the same length as in  FIG. 3 . 
     Pins  21   b - 28   b  are connected in the same way as pins  21 - 28  of  FIG. 3  and pins  21   a - 28   a  of  FIG. 4 . Even the connection types are identical with  FIGS. 3 and 4  and are clearly expressed by identical reference numerals. Windings  41   b ,  42   b ,  43   b  are formed in the same way as is described in  FIGS. 3 and 4 , and connected clockwise to one another by sixth connection type  66 . 
     Three windings  41   b ,  42   b ,  43   b  form a third partial coil by way of one circuit about stator  1 . The partial coil begins with a pin  21   b , which is a fifth end pin. Fifth end pin  21   b  has, however, in contrast to first end pin  21 , connections to two other pins, as is explained in connection to  FIG. 6 . The partial coil ends with pin  28   b  of winding  43   b . Last pin  28   b  of winding  43   b  thus represents a sixth end pin. Sixth end pin  28   b  is in turn designed similar to the first end pin  21 , thus, for example, as a single pin or I pin and has an output  103  for connecting to an energy source. 
       FIG. 6  shows a pin assignment by the first, second, and third partial coils from  FIGS. 3, 4, and 5 , which are depicted by black squares. Identical reference numerals designate identical pins, slots, connections in the figures. 
     Second end pin  28  of third winding  43  of the first partial coil in slot  56 , layer L 2  and third end pin  21   a  of first winding  41   a  of the second partial coil in slot  71 , layer L 5  are connected by a seventh connection type  67 . The seventh connection type bridges a second distance  13 , which is one slot shorter than first distance  11 . Fourth end pin  28   a  of winding  43   a  of the second partial coil in slot  76 , layer L 5  and fifth end pin  21   b  of first winding  41   b  of the third partial coil in slot  81 , layer L 2  are connected by a seventh connection type  67 . The seventh connection type bridges second distance  13 . 
     Seventh connection type  67  thus connects two partial coils respectively, wherein three partial coils form a first coil  201  with an input  101  and an output  103  after three radial circuits clockwise about the stator. 
       FIG. 7  shows stator  1  from  FIG. 2 . The pins are still arranged on concentric circles, thus layers, wherein the concentric circles are not marked for the sake of a better depiction. It depicts which pins, depicted as black squares on a white background, are serially connected to one another and form a first partial coil of a second coil  202 . 
     A first end pin  31  is located in first slot  51  in layer L 6 . First pin  31  is simultaneously also a seventh end pin  31 . This end pin  31  has an input  105  for connecting to an energy source, for example, an inverter. Seventh end pin  31  is therefore only connected to one other pin, thus to a ninth pin  39 . Seventh end pin  31  may thus be configured as a so-called single pin or I pin. First pin  31 , of the seventh end pin, is connected to a ninth pin  39  in a slot  56  by means of first connection type  61 , depicted as a solid line. Ninth pin  39  is located in layer L 5 . A first distance  11 , which is equal to distance  11  from  FIG. 2 , lies between first slot  51  and slot  56 . 
     Ninth pin  39  is connected to a sixth pin  36  in a slot  55  via a sixth connection type  66 , depicted as a dotted line. Sixth pin  36  lies in layer L 2 . Sixth pin  36  is connected to a fifth pin  35  in slot  54  via a fifth connection type  65 , depicted as a loosely dotted line. Fifth pin  35  lies in layer L 1 . Fifth pin  35  is connected to a fourth pin  34  in a slot  55  by means of fourth connection type  64 , depicted as a loosely dashed line. 
     Fourth pin  34  is connected to a third pin  33  via third connection type  63 , depicted as a densely dotted line. Third pin  33  lies in a slot  54 . Third pin  33  lies in layer L 4 . Third pin  33  is connected to a second pin  32  in slot  55  via second connection type  62 , depicted as a short dashed line. Second pin  32  lies in layer L 6 . Second pin  32  lies in slot  55 , thus the same slot as fourth pin  34  and sixth pin  36 . Second pin  32  lies in layer L 6 . There is thus still space for two other pins in layers L 4  and L 5  between second pin  32  and fourth pin  34  in second slot  55 . In addition, there is still space in slot  55  for a further pin in layer L 1 . 
     Second pin  32  is connected to a seventh pin  37  in slot  54  via first connection type  61 , depicted as a solid line. Seventh pin  37  lies in layer L 5 . Seventh pin  37  is located in slot  54 , thus in the same slot as third pin  33  and fifth pin  35 . There is still space for two other pins in layers L 2  and L 3  between fifth pin  35  and third pin  33  in slot  54 . In addition, there is still space in slot  54  for a further pin in layer L 6 . 
     The connection of the second, third, fourth, fifth, sixth and seventh pins  32 - 37  forms a fourth winding  44 . 
     Seventh pin  37  is connected to a tenth pin  36 ( 2 ) via sixth connection type  66 , depicted as a dotted line. Tenth pin  36 ( 2 ) lies in third slot  53  in layer L 2 . At tenth pin  36 ( 2 ), the previously-described serial connection of the consecutive pins in the stator begins again, wherein tenth pin  36 ( 2 ) is similar to sixth pin  36  with an offset of the slot by 120 degrees. 
     The serial connection of tenth pin  36 ( 2 ) to other pins in second slot  52  forms a fifth winding  45 . First, second, third, fourth, and fifth connection types  61 - 65  between these pins is identical to respective first, second, third, fourth, and fifth connection types  61 - 65  of the pins of first through fourth windings  41 - 44 . 
     The two windings  44 ,  45  are connected by sixth connection type  66 . Due to the continuation of the serial connection, sixth winding  46  is formed in two other slots  51  and  56 . Windings  44 - 46  are each connected using sixth connection type  66 . Sixth connection type  66  between the respective windings is thus identical. First, third, fourth, and fifth connection types  61 ,  63 - 65  between the pins of sixth winding  46  are also identical to first, third, fourth, and fifth connection types  61 ,  63 - 65  of preceding windings  41 - 45 . Sixth winding  46  is completed by a connection of an eighth connection type  68 . This connection is shown in  FIG. 10  and is described in conjunction with this figure. 
     Four windings  45 - 48  form a first partial coil by way of one circuit counterclockwise about stator  1 . The first partial coil of second coil  202  ends with an eighth end pin  38 . 
       FIG. 8  shows stator  1  from  FIG. 7 , wherein six other slots  71 - 76  are shown, which are located directly adjacent to slots  51 - 56  from  FIG. 7 . Distance  11  has the same length as in the preceding figures. 
     Pins  31   a - 39   a  are connected in the same way as pins  31 - 39  of  FIG. 7 . Even the connection types are identical with the preceding figures and are clearly expressed by identical reference numerals. Windings  44   a ,  45   a ,  46   a  are formed in the same way as is described in  FIG. 7 , and connected counterclockwise to one another by sixth connection type  66 . 
     Three windings  44   a ,  45   a ,  46   a  form a second partial coil by way of one circuit counterclockwise about stator  1 . The partial coil begins with a pin  31   a , which is a ninth end pin. Ninth end pin  31   a  has, however, in contrast to seventh end pin  31 , connections to two other pins, as is explained in connection with  FIG. 10 . The partial coil ends with pin  38   a  of winding  46   a . Pin  38   a  of winding  46   a  thus represents a tenth end pin  38   a . Furthermore, winding  46   a  has two end pins  31   a ,  38   a.    
       FIG. 9  shows stator  1  from  FIGS. 7 and 8 , wherein six other slots  81 - 86  are shown, which are located directly adjacent to slots  71 - 76  from  FIG. 8 . Distance  11  has the same length as in the preceding figures. 
     Pins  31   b - 39   b  are connected in the same way as pins  31 - 39  of  FIG. 7  and pins  31   a - 39   a  of  FIG. 8 . Even the connection types are identical with the preceding figures and are clearly expressed by identical reference numerals. Windings  44   b ,  45   b ,  46   b  are formed in the same way as is described in  FIGS. 7 and 8 , and connected counterclockwise to one another by sixth connection type  66 . 
     Three windings  44   b ,  45   b ,  46   b  form a third partial coil by way of one circuit about stator  1 . The partial coil begins with a pin  31   b , which is an eleventh end pin. Eleventh end pin  31   b  has, however, in contrast to seventh end pin  31 , connections to two other pins, as is explained in connection with  FIG. 10 . The partial coil ends with pin  38   b  of winding  46   b . Pin  38   b  of winding  46   b  thus represents a twelfth end pin. Twelfth end pin  38   b  is in turn designed similar to the seventh end pin, thus, for example, as a single pin or I pin and has an output  107  for connecting to an energy source. 
       FIG. 10  shows a pin assignment by the first, second, and third partial coils of second coil  202  from  FIGS. 7, 8, and 9 , which are depicted by black squares on a white background. Identical reference numerals designate identical pins, slots, connections in the figures. 
     Eighth end pin  38  of winding  46  of the first partial coil in slot  56 , layer L 3  and ninth end pin  31   a  of winding  46   a  of the second partial coil in slot  71 , layer L 1  are connected by an eighth connection type  68 . The eighth connection type bridges a second distance  13 , which is one slot shorter than the first distance. Tenth end pin  38   a  of winding  46   a  of the second partial coil in slot  76 , layer L 3  and eleventh end pin  31   b  of winding  46   b  of the third partial coil in slot  81 , layer L 1  are connected by eighth connection type  68 . 
     Eighth connection type  68  thus connects two partial coils respectively, wherein three partial coils form second coil  202  with an input  105  and an output  107  after three radial circuits counterclockwise about the stator. A third distance  15 , depicted in the figure, is two slots shorter than first distance  11  from the previous figures. The blocks of the three adjacent slots, which are occupied by pins of the coil, have in each case third distance  15  from one another. 
       FIG. 11  shows first coil  201  and second coil  202  from the previous figures in a stator  1 . Identical reference numerals from the previous figures designate identical pins, slots, and connection types. 
       FIG. 12  shows two other coils, which are respectively formed by pins with a black dot or with a white dot. The three partial coils of the coil with the pins with a white dot are formed according to the description of  FIGS. 3-6 , wherein the slots are offset by 20 degrees in the clockwise direction. The three partial coils of the coil with the pins with a black dot are formed according to the description of  FIGS. 7-10 , wherein the slots are rotated in the clockwise direction by 20 degrees. 
       FIG. 13  shows two other coils, as they are respectively formed by pins with a black cross or with a white cross. The three partial coils of the coil with the pins with a white cross are formed according to the description of  FIGS. 3-6 , wherein the slots are offset by 40 degrees in the clockwise direction. The three partial coils of the coil with the pins with a black cross are formed according to the description of  FIGS. 7-10 , wherein the slots are offset by 40 degrees in the clockwise direction. 
       FIG. 14  shows a pin assignment by the six coils as a combination from  FIGS. 11, 12, and 13 . In particular, it is clear from the location of inputs  101 ,  105 ,  111 ,  115 ,  121 ,  125  and outputs  103 ,  107 ,  113 ,  117 ,  123 ,  127  that an interconnection of the coils may be carried out within twenty four slots. In the stator with fifty four slots, depicted by way of example, an interconnection of the inputs and outputs is thus possible within slightly less than one-half of the stator circumference. Purely with reference to the inputs or outputs, a separate switching would be possible within thirteen slots. 
       FIG. 15  shows the winding scheme of three partial coils of first coil  201 . The consecutive “slot number” is not a reference numeral. The reference numerals with arrows to the slots are identical to the preceding figures and enable a comparison with these figures. 
       FIG. 16  shows the winding scheme of three partial coils of second coil  202 . The consecutive “slot number” is not a reference numeral. The reference numerals with arrows to the slots are identical to the preceding figures and enable a comparison with these figures. 
       FIG. 17  shows on the left a first single pin  211 , also called an I pin. First end pin  21  is located in the center, which is arranged, for example, in first slot  51 , layer L 5  of the stator. The reference numerals are identical to the previous figures. First single pin  211  is depicted with first end face  7  upwards, when viewed from the stator center. At the lower end, first single pin  211  has a pin foot  61   a  with a first weld point  231 . Input  101 ,  111 ,  121  is located at the upper end. 
     A second single pin  212  is shown to the right in  FIG. 17 . Sixth end pin  28   b  is located in the center, which is arranged, for example, in slot  86 , layer L 2  of the stator. The reference numerals are identical to the previous figures. 
     The pins are depicted with first end face  7  upwards, when viewed from the stator center. At the lower end, second single pin  212  has a pin foot  65   b  with a sixth weld point  236 . Output  103 ,  113 ,  123  is located at the upper end. 
       FIG. 18  shows on the left a third single pin  213 , also called an I pin. Seventh end pin  31  is located in the center, which is arranged, for example, in first slot  51 , layer L 6  of the stator. The reference numerals are identical to the previous figures. Single pin  213  is depicted with first end face  7  upwards, when viewed from the stator center. At the lower end, third single pin  213  has a pin foot  61   b  with a second weld point  232 . Input  105 ,  115 ,  125  is located at the upper end. 
     A fourth single pin  214  is shown to the right in  FIG. 18 . Twelfth end pin  38   b  is located in the center, which is arranged, for example, in slot  86 , layer L 4  of the stator. The reference numerals are identical to the previous figures. The pins are depicted with first end face  7  upwards, when viewed from the stator center. At the lower end, fourth single pin  214  has a pin foot  63   a  with a third weld point  233 . Output  107 ,  117 ,  127  is located at the upper end. 
       FIG. 19  shows a first double pin  215 , or U pin, which establishes second connection type  62  between a second pin  22 ,  22   a ,  22   b ,  32 ,  32   a ,  32   b  and a third pin  23 ,  23   a ,  23   b ,  33 ,  33   a ,  33   b . Double pin  215  may bridge first distance  11  between the slots. At the lower end, the double pin has two inwardly-bent pin feet  63   a ,  61   b , with a third weld point  233  and a second weld point  232 . 
       FIG. 20  shows a second double pin  216 , or U pin, which establishes fourth connection type  64  between a fifth pin  25 ,  25   a ,  25   b ,  35 ,  35   a ,  35   b  and a fourth pin  24 ,  24   a ,  24   b    34 ,  34   a ,  34   b . Double pin  216  may bridge first distance  11  between the slots. At the lower end, the double pin has two inwardly-bent pin feet  65   a ,  63   b , with a fifth weld point  235  and a fourth weld point  234 . 
       FIG. 21  shows a third double pin  217 , or U pin, which establishes sixth connection type  66  between a sixth pin  26 ,  26   a ,  26   b ,  36 ,  36   a ,  36   b ,  36 ( 2 ),  36   a ( 2 ),  36   b ( 2 ) and a seventh or ninth pin  27 ,  27   a ,  27   b ,  37 ,  37   a ,  37   b ,  39 ,  39   a ,  39   b . Third double pin  217  may bridge first distance  11  between the slots. At the lower end, the double pin has two outwardly-bent pin feet  65   b ,  61   a , with a sixth weld point  236  and a first weld point  231 . 
     Distance  11  is identical only with respect to the number of slots to be bridged. The actual spatial distance to be bridged differs, because the double pins connect different layers. 
       FIG. 22  shows a fourth double pin  218 , or U pin, which establishes seventh connection type  67  between a second or fourth end pin  28 ,  28   a  and a third or fifth end pin  21   a ,  21   b . Fourth double pin  218  may bridge second distance  13 , thus is one slot smaller than first distance  11 . At the lower end, fourth double pin  218  has two outwardly-bent pin feet  65   b ,  61   a , with a sixth weld point  236  and a first weld point  231 . 
       FIG. 23  shows a fifth double pin  219 , or U pin, which establishes eighth connection type  68  between an eighth or tenth end pin  38 ,  38   a  and a ninth or eleventh end pin  31   a ,  31   b . Fifth double pin  219  may bridge second distance  13 , thus is one slot smaller than first distance  11 . At the lower end, fifth double pin  219  has two inwardly-bent pin feet  63   a ,  61   b , with a third weld point  233  and a second weld point  232 . 
     The different single and double pins in  FIGS. 17 to 23  have similar pin feet. First connection type  61  is formed by welding first weld point  231  on pin foot  61   a  to second weld point  232  on pin foot  61   b  according to the winding scheme. Third connection type  63  is formed by welding third weld point  233  on pin foot  63   a  to fourth weld point  234  on pin foot  63   b  according to the winding scheme. Fifth connection type  65  is formed by welding fifth weld point  235  on pin foot  65   a  to sixth weld point  236  on pin foot  65   b  according to the winding scheme. The single pins are also connected to the double pins via the respective connection type, so that the pins circulate the stator as continuous electrical conductors.  FIG. 24  is a basic sketch of an exemplary embodiment of a vehicle  403 , for example, a hybrid vehicle or an electric vehicle, comprising an electric machine  401 , in particular an electric motor, with an exemplary embodiment of stator  1  for driving vehicle  403 . Furthermore, vehicle  403  may have an inverter  405 , which supplies electric machine  401  with an alternating current from a direct current source. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  Stator 
           2 ,  3 ,  21 - 38   b  Pin 
           5 ,  51 - 58 ,  71 - 78  Slot 
           81 - 88 ,  91 - 96  Slot 
           7  First end face 
           9  Second end face 
           11  First distance 
           13  Second distance 
           15  Third distance 
           21  First end pin 
           28  Second end pin 
           21   a  Third end pin 
           28   a  Fourth end pin 
           21   b  Fifth end pin 
           28   b  Sixth end pin 
           31  Seventh end pin 
           38  Eighth end pin 
           31   a  Ninth end pin 
           38   a  Tenth end pin 
           31   b  Eleventh end pin 
           38   b  Twelfth end pin 
           41 - 46 ,  41   a - 46   a ,  41   b - 46   b  Winding 
           61  First connection type 
           62  Second connection type 
           63  Third connection type 
           64  Fourth connection type 
           65  Fifth connection type 
           66  Sixth connection type 
           67  Seventh connection type 
           68  Eighth connection type 
           61   a, b ,  63   a, b ,  65   a, b  Pin feet 
           101 ,  105 ,  111 ,  115 ,  121 ,  125  Input 
           103 ,  107 ,  113 ,  117 ,  123 ,  127  Output 
           211  First single pin 
           212  Second single pin 
           213  Third single pin 
           214  Fourth single pin 
           215  First double pin 
           216  Second double pin 
           217  Third double pin 
           218  Fourth double pin 
           219  Fifth double pin 
           231  First weld point 
           232  Second weld point 
           233  Third weld point 
           234  Fourth weld point 
           235  Fifth weld point 
           236  Sixth weld point 
           201  First coil 
           202  Second coil 
           401  Electric machine 
           403  Vehicle 
           405  Inverter 
         L 1 , L 2 , L 3 , L 4 , L 5 , L 6  Layer 
         M Stator center