Patent Publication Number: US-2022224184-A1

Title: Drive motor with a groove cover

Description:
The invention relates to a drive motor for a suction device or a machine tool in the form of a handheld power tool or a semi-stationary machine tool, wherein the drive motor includes a stator having an excitation coil assembly and a rotor having a motor shaft, which is rotatably mounted around a rotational axis on the stator or with respect to the stator by means of a bearing assembly, wherein the rotor is received in a rotor receptacle of the stator, the inner circumference of said receptacle having grooves which extend along longitudinal axes that run parallel to the rotational axis in particular and have insertion openings which are open towards the rotational axis and are provided for inserting excitation coils of the excitation coil assembly and are closed by groove covers, wherein the groove covers are in engagement with the engage-behind contours of the grooves at their opposite longitudinal sides, each of which extends along the longitudinal axis of the respective groove, said longitudinal axis being transverse to a transverse spacing between the longitudinal sides, and the groove covers have a wall section for covering the groove between the longitudinal sides, wherein the engage-behind contours support the groove cover towards the rotational axis and hold the groove cover in the respective groove. The invention furthermore relates to a method for arranging such a groove cover on such a drive motor. 
     Motors with such groove covers are explained, for example, in U.S. Pat. No. 6,713,927 B2 or DE 38 90 737 C2. The groove covers are typically designed in the form of flexurally rigid rods which are pushed into the grooves from the respective end faces or longitudinal end regions of the stator. The further the groove cover is inserted into the groove, the greater the frictional resistance. The groove covers must be designed to be correspondingly flexurally rigid. 
     It is therefore the object of the present invention to provide an improved drive motor. 
     To achieve the object, it is provided in a drive motor of the type mentioned at the outset that the transverse spacing of the longitudinal sides of at least one groove cover can be modified such that the groove cover can be inserted into the groove past the engage-behind contours of the groove in a movement direction radial to the rotational axis of the rotor and can be brought into behind engagement with the engage-behind contours of the groove. 
     The methods provides for: 
     introducing at least one groove cover into the rotor receptacle and moving the groove cover into the groove in a movement direction radially to the rotational axis of the rotor, with the transverse spacing of the longitudinal sides of the groove cover being modified in such a way that the groove cover engages behind the engage-behind contours of the groove past the engage-behind contours of the groove into the groove and on the longitudinal sides. 
     The gripping-behind contours extend, for example, directly at the edges of the insertion opening and, so to speak, reduce its insertion cross section. 
     The groove cover preferably has a longitudinal shape with a longitudinal axis. When the groove cover is arranged in the groove, the longitudinal axes of the groove and the groove cover run parallel to one another. Thus, when reference is made to a longitudinal axis of the groove, the longitudinal axis of the groove cover can also be addressed at the same time. 
     A basic idea here is that the groove cover is, so to speak, inserted into the groove from the interior of the rotor receptacle so that it locks in the groove, for example. Assembly is much simpler than, for example, when a groove cover is introduced frontally, as is customary in the prior art. The groove cover can also be designed to be significantly less flecturally rigid in its longitudinal direction, for example, because it does not have to be loadable along its longitudinal axis for a plugging movement. Rather, flexural flexibility or resilience is even preferred, in particular transversely to the longitudinal axis of the groove or groove cover. 
     For example, the wall section of the groove cover is designed as a flexurally flexible section or has such a flexurally flexible section, wherein the flexurally flexible section can be deformed in terms of reducing the transverse spacing of the longitudinal sides of the groove cover transversely to the longitudinal axis or a narrowing of the groove cover transversely to the longitudinal axis. Thus, the longitudinal sides or longitudinal flanks of the groove cover can be deformed towards one another in order to reduce the transverse spacing between the longitudinal sides and thus enable introduction into the insertion opening of the groove. 
     The groove cover advantageously forms a locking body which can be inserted into the groove in a movement direction radially with respect to the rotational axis of the drive motor and can be locked in the engage-behind contours. The locking function is possible, for example, on the basis of the flexurall flexible section already mentioned. However, it is also possible for locking contours to be present on the side of the groove cover, for example spring-loaded locking bodies or the like, which can engage with the formfitting contours of the groove. At this point it should be mentioned that a flexible configuration of at least one wall section or another part of the groove cover is preferred. In principle, however, it is conceivable that the groove cover comprises a wall body that is inherently fixed transversely to the longitudinal sides or with regard to the transverse spacing, but on the longitudinal sides of which there are flexible parts. In principle, a telescopic groove cover would also be conceivable, which has telescopic sections in terms of reducing and enlarging the transverse spacing of its longitudinal sides. 
     It is advantageous if the groove forms a tension body or clamping body that can be tensioned with the groove, which is tensioned or clamped with the groove in a state of being received in the groove. For example, the groove cover is supported on side walls of the groove that extend in the direction of the longitudinal axis. 
     It is furthermore advantageous if the groove cover is tensioned with the groove in the state of being received in the groove transversely to the longitudinal axis in terms of increasing the transverse spacing. 
     The groove cover, for example its wall section, preferably has an arched, curved or barrel-shaped cross section transversely to the longitudinal axis or its longitudinal extension. Such an arched or curved cross section enables a particularly simple displacement or deformation of the wall section in terms of reducing and then enlarging the transverse spacing between the longitudinal sides. The groove cover has the arched and/or curved and/or barrel-shaped cross section advantageously in a state inserted into the groove and/or in a state not inserted into the groove and/or in the unloaded state and/or before insertion into the groove and/or without a force acting on it. The groove cover has, for example, its greatest length in its longitudinal extension. The cross section of the groove cover extends, for example, between narrow sides or long sides of the groove cover. The groove cover preferably has a bulge or curvature between its narrow sides or long sides. 
     It is preferred if the groove cover as a whole, but preferably the wall section, is curved into an interior space of the groove or away from the rotational axis. Thus, the groove cover does not protrude into the rotor receptacle rather bulges away from it, so to speak. As a result, the freedom of movement for the rotor is not restricted. In principle, however, the reverse configuration is also conceivable, in that the bulge of the groove cover is oriented towards the rotational axis of the rotor. 
     Only low joining forces are required to introduce the groove cover into the groove. In particular, the introduction of the groove cover into the groove is facilitated, for example, by a flexibility transverse to the longitudinal extent or longitudinal axis of the groove cover and/or by the insertion bevel or displacement contour of the groove cover explained below. 
     Furthermore, an insertion bevel or displacement contour is advantageously provided on the groove cover, which is suitable for inserting the groove cover into the insertion opening of the groove. The insertion bevel makes it easier to insert the groove cover into the groove. The displacement contour is advantageously suitable for deforming the groove cover in terms of reducing the transverse spacing between its longitudinal sides. 
     The insertion bevel or displacement contour is, for example, an inclined surface, a bulged surface or the like. In particular, the already mentioned bulged outer contour of the wall section can represent or form the insertion bevel or displacement contour. 
     When a force is applied to the groove cover in the radial direction with respect to the rotational axis into the insertion opening of the groove, the insertion bevel or displacement contour expediently brings about a force on the groove cover in terms of reducing the transverse spacing between the longitudinal sides of the groove cover. The groove cover is thus, so to speak, deformed into a narrower shape by the application of force brought about by the insertion bevel or displacement contour. 
     The groove advantageously has at least one support contour for supporting the groove cover in a direction of force radially outward with respect to the rotational axis. For example, the support contour is opposite the at least one engage-behind contour. The support contour and the engage-behind contour can form, for example, a V-shaped or U-shaped configuration. For example, the support contour is, so to speak, the support contour that supports towards the bottom of the groove. The engage-behind contour acts in a supporting manner during or against a movement of the groove cover out of the groove or prevents the groove cover from moving out of the groove. 
     In principle, it is possible for the support contour and the engage-behind contour to be provided on mutually opposite sides, for example a formfitting projection that protrudes into the interior of the groove. 
     The at least one engage-behind contour and/or the at least one support contour are preferably designed as, in particular, planar or flat support surfaces or resting surfaces or stop surfaces. 
     The groove cover has an engage-behind surface associated with the engage-behind contour of the groove . 
     If the groove provides a support contour, the groove cover has a support surface associated with it for support on the support contour. 
     It is advantageous if the support surface of the groove cover is designed as an insertion bevel or displacement contour for inserting the groove cover into the insertion opening of the groove. 
     The support contour and/or the engage-behind contour and/or the support surface and/or the engage-behind surface are advantageously planar or flat surfaces. However, it is also possible for one or more of the aforementioned contours or surfaces to have a bulge. The support contour and the engage-behind contour preferably directly adjoin one another. The support contour and the engage-behind contour are advantageously at an angle, in particular at an obtuse angle. The support contour and the engage-behind contour advantageously enclose an angle, in particular an obtuse angle. 
     The support contour and the engage-behind contour are preferably opposite one another. 
     The support surface and the engage-behind surface of the groove cover are preferably at an angle, in particular at an obtuse angle, to one another and/or directly adjoin one another. The support contour and/or engage-behind contour are preferably facing away from one another. 
     On at least one longitudinal side of the groove cover, preferably on both longitudinal sides, a formfitting projection for engaging a formfitting receptacle of the groove or a formfitting receptacle for engaging a formfitting projection of the groove is arranged. That is to say both is possible, that the groove has a formfitting projection that engages in a formfitting receptacle of the groove cover or, conversely, that the groove cover has a formfitting projection that engages in a formfitting receptacle of the groove, as shown by the example in the drawing. Formfitting projections or formfitting receptacles are preferably provided on the mutually opposite longitudinal sides of the groove cover, but it is also possible for a formfitting projection to be present on one longitudinal side of the groove cover and a formfitting receptacle on the other longitudinal side. 
     The groove has a formfitting receptacle for the formfitting projection of the groove cover, and a formfitting projection for the formfitting receptacle of the groove cover, that is to say, for example opposing formfitting projections or formfitting receptacles or one formfitting projection and one formfitting receptacle opposite one another. 
     The engage-behind contour of the groove and/or the support contour of the groove are/is preferably provided on the respective formfitting projection or the formfitting receptacle of the groove. 
     It is also advantageous if the engage-behind surface and/or the supporting-surface are/is provided at the formfitting projection or the formfitting receptacle of the groove cover. 
     A section of the formfitting projection that protrudes furthest defines the transverse spacing between the longitudinal sides of the groove cover. Preferably, the groove cover has one formfitting projection each on opposite longitudinal sides, the most protruding sections of which define the transverse width of the groove cover or the transverse spacing of the longitudinal sides. 
     Preferably, the at least one formfitting projection or the at least one formfitting receptacle of the groove cover can be moved transversely to the longitudinal axis in the direction of a transverse center in terms of reducing the transverse spacing between the longitudinal sides of the groove cover. This can be implemented, for example, in that the wall section of the groove cover is flexurally flexible. 
     The formfitting projection or the formfitting receptacle preferably extends over the entire length of the groove cover and/or the groove with respect to the longitudinal axis. 
     Otherwise, however, a segmented construction would also be possible, that is, for example, with respect to the longitudinal axis, two or more formfitting projections or formfitting receptacles are arranged next to one another, but at a longitudinal spacing from one another. 
     The formfitting projection and the formfitting receptacle are preferably complementary to one another. The formfitting projection therefore fits into the respective formfitting receptacle. In the case of the formfitting projection and the formfitting receptacle, a U-shaped or V-shaped cross sectional contour or shape is advantageous. It is preferred if the side flanks of the formfitting projection and the formfitting receptacle have a large angular spacing of, for example, at least  90  degrees from one another. 
     It is also advantageous if there is a spacing or free space between the groove cover and the coil conductors, which are arranged in the groove. 
     It is advantageously provided that the groove cover is not designed to hold and/or support coils or coil conductors of the stator coil assembly received in the groove. If, for example, a coil or a coil conductor acts on the groove cover in terms of removal, the groove cover yields and/or is released from the groove. 
     It is also advantageous if the engage-behind contour and/or a engage-behind surface of the groove cover has, or is designed as, a release bevel for support on the at least one engage-behind contour of the groove, which when force is applied to the groove cover in the radial inside direction with respect to the rotational axis, acts on the groove cover in terms of releasing the groove cover from the groove and/or in terms of deforming the groove cover in terms of narrowing. If, for example, a coil or a coil conductor of the stator coil assembly acts on the groove cover and/or exerts a force in terms of removing from the groove, the engage-behind contour or the engage-behind surface or both, engage-behind contour and engage-behind surface, act in terms of releasing the groove cover from the groove. For example, the groove cover becomes narrower due to the release bevel or release bevels, so that it comes out of the groove and/or a form fit between the groove cover and the groove is eliminated. 
     It is advantageous if the engage-behind contour of the groove and the or a engage-behind surface of the groove cover abutting against the engage-behind contour are designed as sealing surfaces which advantageously abut flat against one another. It is also advantageous if the support contour of the groove and the or a support surface of the groove cover abuting against the support contour are designed as a sealing surface, which advantageously abut flat against one another. In particular, the support contour and the engage-behind contour, as well as the support surface and the engage-behind surface of the groove cover abuting against it, form a sealing profile. 
     The wall section of the groove cover preferably forms a base leg of the groove cover, from which at least one lateral leg protrudes at an angle, which runs parallel to the longitudinal axis and engages one of the engage-behind contours of the groove. Lateral legs of this type are preferably arranged on opposite sides of the base leg. 
     A free end region of the at least one lateral leg or the lateral legs is preferably oriented or inclined towards the wall section, so that a formfitting projection for engaging in a formfitting receptacle of the groove is formed in a transition region between the wall section and the lateral leg. The formfitting projection is therefore located on the longitudinal outer sides or longitudinal sides of the groove cover. 
     The groove cover expediently forms a wall body or profile body or is formed thereby. 
     For example, the groove cover is made of plastic, in particular of polyamide. The groove cover can be fiber-reinforced, in particular glass fiber-reinforced. Fibers of the fiber reinforcement preferably run parallel or essentially parallel to the longitudinal axis of the groove cover or the groove. 
     It is advantageous if the groove cover is obtained by a roll material unwound from a coil, which is deformed into a linear elongated form and severed from the roll material. Unwinding a roll material from a coil and severing a length of the roll material to provide the at least one groove cover is therefore preferred. It may be necessary to first bring the roll material into an elongated linear shape before it is introduced into the groove. For this purpose, a smoothing device, for example comprising pressing elements, heating devices or the like, is preferably provided. 
     It is possible that the groove cover is only seated in the groove with a clamping fit or tension fit. However, it is also possible that the groove cover is firmly bonded to the groove, for example glued, welded or the like. 
     An advantageous concept provides that the groove cover is fixed, in particular welded, to at least one longitudinal end region of the stator by a bearing cover that closes the stator frontally. For example, the bearing cover has a receptacle in which a section of the groove cover, in particular protruding in front of the stator or its carrier package, is received. It is also possible that when welding, gluing or otherwise firmly bonding the bearing cover to the stator, a material of the stator, in particular of a carrier body on which the laminated core of the stator is arranged, melts and bonds with the groove cover. 
     A magnet assembly arranged on the rotor comprises magnets, in particular permanent magnets. 
     For example, magnet bodies of the magnets which are magnetized or suitable for magnetization on the laminated core of the rotor consist of aluminum-nickel-cobalt, Bismanol, thus an alloy made up of bismuth, manganese, and iron, of a ferrite, for example a hard-magnetic ferrite, for example based on barium, strontium, of neodymium-iron-boron (NdFeB), advantageously with an additive of dysprosium, of samarium-cobalt (SmCo), advantageously having 20-25% iron component, e.g., SmCo 5 , Sm 2 Co 17 , Sm(Co,Cu,Fe,Zr) z , or the like. Rare-earth magnets or plastic magnets are also suitable. Furthermore, AINiCo alloys, PtCo alloys, CuNiFe and CuNiCo alloys, FeCoCr alloys, martensitic steels, or MnAIC alloys are suitable for the magnet bodies. 
     The drive motor is preferably a brushless motor or electronically commutated motor. In particular, it is advantageous if the respective stator of the drive motor includes permanent magnets or is excited by permanent magnets. 
     Laminated cores of the rotor and/or the stator are preferably produced from layered electrical sheets or transformer sheets. 
     A stator of the drive motor expediently comprises a carrier body made of plastic, in particular made of polyamide. The carrier body is produced, for example, by potting and/or extrusion coating the laminated core of the stator. It is also possible that the carrier body comprises one or more plug bodies or plug carrier bodies, which are plugged onto the laminated core. For example, such a plug carrier body can be plugged onto one or both end sides of the laminated core. The carrier body preferably covers the laminated core in the region of the rotor receptacle and/or in the region of one or both end sides of the laminated core. Supports, support projections, winding heads, and the like for accommodating coil conductors of the excitation coil assembly are preferably provided on the carrier body. Furthermore, the carrier body preferably includes electrical connecting contacts or connecting units for connecting a connecting line, using which the drive motor is connectable or connected to an energizing unit. 
    
    
     
       Exemplary embodiments of the invention are explained hereinafter on the basis of the drawings. In the figures: 
         FIG. 1  shows a perspective diagonal illustration of a system of two electric drive motors and hand-held power tools which include these drive motors, 
         FIG. 2  shows a side view of the one drive motor of the system according to  FIG. 1 , of which in 
         FIG. 3  a section is shown along a section line A-A  FIG. 2 , 
         FIG. 4  shows a section through the other drive motor of the system according to  FIG. 1 , approximately along the same section line A-A corresponding to  FIG. 2 , 
         FIG. 5  shows an insulation sleeve of the drive motor according to  FIG. 4  in a perspective illustration, 
         FIG. 6  shows a perspective illustration of a rotor of the drive motor according to  FIG. 4 , 
         FIG. 7  shows a sectional illustration through the rotor according to  FIG. 6  during its production, approximately along a section line B-B in  FIG. 6 , 
         FIG. 8  shows the view approximately corresponding to  FIG. 7 , wherein the motor shaft is inserted completely into the rotor laminated core, however, 
         FIG. 9  shows a detail D 1  from  FIG. 8 , 
         FIG. 10  shows a perspective diagonal view of the stator according to  FIG. 1 , approximately corresponding to a detail D 2  in  FIG. 1 , 
         FIG. 11  shows a section along a section line C-C through the stator according to  FIG. 10  to illustrate a connecting unit, which in 
         FIG. 12  is shown laterally in the open state and in 
         FIG. 13  is shown laterally in the closed state, 
         FIG. 14  shows a perspective illustration of the connecting unit according to  FIG. 12 , and 
         FIG. 15  shows a perspective illustration of the connecting unit according to  FIG. 13 , 
         FIG. 16  shows a perspective diagonal illustration to illustrate an installation and processing of the connecting unit according to  FIGS. 10 to 14  in a perspective diagonal illustration, approximately corresponding to  FIG. 10  with a welding gun, 
         FIG. 17  shows a section through the arrangement according to  FIG. 16  approximately along a section line D-D, 
         FIG. 18  shows the image according to  FIG. 17 , but with welding gun arms moved toward one another, 
         FIG. 19  shows a detail D 3  of the stator according to  FIG. 1  with a groove cover, which in 
         FIG. 20  is shown diagonally in perspective, 
         FIG. 21  shows a detail D 4  from  FIG. 19  during an installation of the groove cover according to  FIG. 17  in a stator groove, 
         FIG. 22  shows detail D 4 , but with groove cover adjusted further in the stator groove, and 
         FIG. 23  shows detail D 4  with fully installed groove cover, 
         FIG. 23B  shows alternative embodiments of a groove cover and a groove, approximately corresponding to the view according to  FIG. 23 , 
         FIG. 24  shows a schematic illustration of an installation unit for producing the groove cover according to  FIG. 19  and its installation on the stator according to  FIGS. 21 to 23 , 
         FIG. 25  shows a perspective diagonal view of a detail of a rotor of the above-mentioned motor, approximately corresponding to a detail D 5  in  FIG. 6 , and 
         FIG. 26  shows a schematic illustration of a balancing unit for balancing the rotor according to the above figure, and 
         FIG. 27  shows a schematic frontal view of the rotor according to the above figure with a magnetizing device. 
     
    
    
       FIG. 1  shows a system illustration comprising a hand-held power tool  300 , for example a saw, in which a drive motor  20  drives a tool receptacle  301  for a working tool, for example directly or via a gearing (not visible in the drawing). A working tool  302 , for example a cutting tool, sawing tool, or the like is arrangeable or arranged on the tool receptacle  301 . The drive motor  20  is accommodated in a housing  303  of the power tool  300  and can be switched on and switched off by means of a switch  304 . A speed of the drive motor  20  is preferably also adjustable using the switch  304 . 
     A connecting cable  305  for connection to a power supply grid EV is used for the electrical power supply of the hand-held power tool  300 . The power supply grid EV provides a supply voltage P 1 , for example 110 V AC voltage, 230 V AC voltage, or the like. The hand-held power tool  300  can include an energizing unit  306  connected between the switch  304  and the drive motor  20 . 
     The drive motor  20  can also be provided to operate a suction device  400 , in particular to drive a suction turbine of the suction device  400 . The suction device  400  includes the drive motor  20  and is connectable, for example, by means of a connecting cable  405  to the power supply grid EV. 
     The voltage P 1  is in any case significantly greater, for example at least four times to five times greater, than a voltage P 2 , which an energy accumulator  205  of a hand-held power tool  200  provides. The voltage P 2  is, for example, a DC voltage of 14 V, 18 V, or the like. 
     The hand-held power tool  200  is, for example, a power screwdriver, drill, or the like. A drive motor  120 , which is suitable for the lower voltage P 2 , is accommodated in a housing  203  of the hand-held power tool  200 . The drive motor  120  is energized by an energizing unit  206 , which is supplied with electrical energy by the energy accumulator  205 . The drive motor  120  drives a tool receptacle  201  for a working tool  202 , for example a drilling tool or screwing tool, directly or via a gearing  208 . The energizing unit  206  can be switched on, switched off, and/or designed for adjusting a speed of the drive motor  120  by way of a switch  204 . 
     The drive motors  20 ,  120  include partially identical or similar components. 
     For example, motor shafts  30  and  130  alternately usable in the drive motors  20 ,  120  each include bearing portions  31 ,  32 , between which a holding portion  33  is provided. The bearing portion  32  is located adjacent to an output portion  34 , which is used to drive the tool receptacle  201  or  301 . For example, a gearwheel can be arranged or arrangeable on the output portion  34 . Alternatively, gear teeth  35  are provided as indicated in the case of a motor shaft  130 . The holding portion  33  preferably includes a formfitting contour  36 , which extends between planar portions  37 , which thus do not include a formfitting contour. 
     The formfitting contour  36  comprises, for example, grooves and/or projections  36 A extending in parallel to a longitudinal axis L of the motor shaft  30 . However, a fluting, a honeycomb-like structure, or the like can also be provided as the formfitting contour  36 . 
     A formfitting contour  136  of the motor shaft  130  comprises, for example, formfitting projections  136 A inclined obliquely to the longitudinal axis L. The formfitting projections  136 A have a slight oblique inclination, however, for example between 5 and 15°, so that the formfitting projections  136 A extend essentially in parallel to the longitudinal axis L. 
     The formfitting contours  36 ,  136  form, for example, formfitting contours  36 B,  136 B. 
     The output portion  34  can be provided to drive a fan wheel. For example, a fan wheel holder  38  is provided on the motor shaft  130 , which is arranged, for example, between the gear teeth  35  and the bearing portion  32 . 
     The motor shaft  30  or  130  is connectable in a rotationally-fixed manner to a laminated core  41  or  141  of a rotor  40 ,  140 . The laminated cores  41 ,  141  include sheets  43  arranged adjacent to one another in a series arrangement transverse to the longitudinal axis L, for example electrical sheets or transformer sheets, in a way known per se. 
     The laminated cores  41 ,  141  include shaft through-openings  42 ,  142 , which have different diameters. The shaft through-opening  42  has a larger diameter than the shaft through-opening  142 . The motor shaft  30  or  130  can be inserted by means of an insulation sleeve  60  into the shaft through-opening  42 , while the motor shafts  30  or  130  can be inserted directly into the shaft through-opening  142 , i.e., an insulation sleeve or similar other body is not necessary. 
     The insulation sleeve  60  forms an insulation body  60 A, by means of which the laminated core  41  is electrically insulated from the respective motor shaft  30  or  130  carrying it. 
     Magnet assemblies  50  are arranged on the laminated cores  41  and  141 . The laminated cores  41  or  141  include holding receptacles  45  for magnets  50  of the magnet assemblies  50 . For example, four holding receptacles  45  and associated magnets  51  are provided, so that the rotor  40 ,  140  forms a total of four magnetic poles. The magnets  51  are, for example, permanent magnets. 
     The magnets  51  have, for example, a plate-shaped design. The magnets  51 , for example, magnet plates or plate bodies  56 . The holding receptacles  45  are accordingly suitable for accommodating plate-shaped, thus flat rectangular, cubic plate bodies or magnet plates and include corresponding inner circumferential contours. 
     The holding receptacles  45  and the magnets  51  extend in parallel to the longitudinal axis L of the motor shaft  30 ,  130  or in parallel to the rotational axis D of the motor  20 ,  120 . 
     Furthermore, the rotor  40 , in particular as the laminated core  41 ,  141 , is penetrated by air ducts  46 , which extend in parallel to the longitudinal axis L of the motor shaft  30 ,  130  and are open at the end sides  44  of the rotor  40 ,  140 , so that air can flow through the laminated cores  41 ,  141 . 
     The shaft through-opening  42 ,  142  does have an essentially circular inner circumferential contour, but advantageously additionally also has a twist-lock contour  47 , in particular a twist-lock receptacle  47 A. The twist-lock contour  47  is, for example, a longitudinal groove  47 B, which extends in parallel to the rotational axis D or longitudinal axis L. 
     Both motor shafts  30 ,  130  can each be inserted into the laminated cores  41 ,  141 . 
     In the laminated core  141 , the shaft through-opening  142  of which has a smaller diameter than the shaft through-opening  42  of the other laminated core  41 , the respective motor shaft  30 ,  130  can be inserted directly into the shaft through-opening  142 , for example pressed in. 
     The narrow sides or end sides of the sheets  43 , which delimit the inner circumference of the shaft through-opening  42  or protrude into it, advantageously claw together with the motor shaft  30 ,  130 , so that it is accommodated non-displaceably in the laminated core  141  in a first direction parallel to the rotational axis D or to its longitudinal axis L. An electrical conductivity of the laminated core  141  and the motor shaft  30 ,  130 , which preferably consists of metal, is possible in spite of the direct contact between the laminated core  141  and the motor shaft  30 ,  130 , because the rotor  140  is provided for use with the drive motor  120  and thus for the lower voltage P 2 . 
     In contrast, insulation measures are taken in the rotor  40 , so that in spite of the electrical conductivity of the motor shaft  30 ,  130  and of the associated laminated core  41 , electrical safety is provided. 
     Specifically, the motor shaft  30 ,  130  is accommodated by means of an insulation sleeve  60  in the laminated core  41 . The insulation sleeve  60  thus more or less forms a protective jacket or an outer envelope of the motor shaft  30 ,  130  in the section which is accommodated in the shaft through-opening  42 . 
     The insulation sleeve  60  includes a tube portion  63  between its longitudinal ends  61 ,  62 , which is arranged in a sandwiched manner between the laminated core  41  and the motor shaft  30 ,  130  and electrically insulates it from the laminated core  41 . 
     The tube portion  63  includes a socket  64  for inserting through the motor shaft  30 ,  130 , which extends from the longitudinal end  61  to the longitudinal end  62 . In the region of the longitudinal end  61 , the socket  64  has an insertion opening  64 A, through which the motor shaft  30  is insertable into the socket  64 . The motor shaft  30  exits from the socket  64  at an exit opening  64 B. 
     In the region of the longitudinal end  61 , i.e., a longitudinal end region  61 A, the socket  64  has a larger diameter W 1  and thus a larger inner cross section WQ 1  than in the region of the longitudinal end  62 , i.e., a longitudinal end region  62 A, where a smaller diameter W 2  and thus a smaller inner cross section WQ 2  is provided. For example, the diameter of the motor shaft  30 ,  130  is approximately 10 mm in the region of the longitudinal ends  61 ,  62 . In contrast, the diameter W 2  is smaller by approximately 0.2 mm to 0.3 mm than the diameter W 1  before the motor shaft  30 ,  130  is inserted into the socket  64 . Thus, when the motor shaft  30 ,  130  is inserted along an insertion axis S into the insulation sleeve  60  from the longitudinal end  61  to the longitudinal end  62 , as indicated in  FIG. 7 , it first penetrates slightly or with transverse play with respect to the insertion axis S into the insertion opening  64 A at the longitudinal end  61 , where the socket  64  has the diameter W 1 . The diameter W 1  is advantageously somewhat larger than the diameter of the motor shaft  30 ,  130  at its free longitudinal end provided to be inserted into the socket  64 . The region of the insertion opening  64 A forms a centering section, in which the motor shaft  30 ,  130  is centered with respect to the insulation sleeve  60  or the rotational axis D. For example, the motor shaft  30  has the same outer cross section or outer diameter both in the region of the diameter W 1  and also in the region of the diameter W 2 . 
     Alternatively or additionally, it is possible that, for example, the motor shaft  30  includes a first outer cross section AQ 1  and a second outer cross section AQ 2 , which are associated with the longitudinal ends  61 ,  62  of the socket  64 , wherein the first outer cross section AQ 1  is smaller than the second outer cross section AQ 2 . In this design of the motor shaft  30 , it is also possible that the diameters W 1  and W 2  and thus the inner cross sections of the socket  64  are identical or approximately equal in the region of the longitudinal ends  61  and  62 . 
     The socket  64  becomes narrower from the diameter W 1  to the diameter W 2 , preferably continuously, between the longitudinal ends  61 ,  62 . However, it would also be possible that at least one step is provided between the diameter W 1  and the diameter W 2 . The socket  64  advantageously includes a plug cone, which becomes narrower from the longitudinal end  61  to the longitudinal end  62 . 
     Insertion bevels  65 , for example an insertion cone, are advantageously provided at the longitudinal end  61  in order to facilitate the insertion process of the motor shaft  30 ,  130  into the socket  64 . 
     When the motor shaft  30 ,  130  is inserted along the insertion axis S into the socket  64 , it penetrates further and further in the direction of the longitudinal end  62 , wherein it more or less widens the tube portion  63 , which becomes narrower toward the longitudinal end  62 . 
     The installation is structured as follows: 
     First the insulation sleeve  60  is inserted into the shaft through-opening  42  of the laminated core  41 . 
     It is advantageously provided that the insertion cross section or inner cross section of the shaft through-opening  42  is equal or approximately equal over its entire length provided for the insertion of the insulation sleeve  60 . 
     However, it is also possible that the shaft through-opening  42  has a larger inner cross section at a longitudinal end region  41 A provided for inserting the insulation sleeve  60  than at a longitudinal end region  41  B opposite to this longitudinal end region. 
     The motor shaft  30 ,  130  is then inserted into the socket  64 . Therefore, when is inserted along the insertion axis S into the socket  64 , the motor shaft  30 ,  130  presses the radial outer circumference of the tube portion  64  in the direction of the radial inner circumference of the shaft through-opening  42 . The sheets  43  preferably engage with their narrow sides facing toward the shaft through-opening  42  like teeth into the circumferential wall  66 . 
     The socket  64  has the narrower diameter W 2  up into a region in front of the laminated core  41 , so that the motor shaft  30 ,  130 , when it reaches this region of the socket  64 , then widens the circumferential wall  66  of the tube portion  63  radially outward with respect to the insertion axis S and thus more or less stretches the tube or the tube portion  63 . A formfitting section  75  having a step  67  thus forms on the outer circumference of the circumferential wall  63 , which directly engages in or engages behind the end side  44  of the laminated core  41 . The step  63  thus holds the insulation sleeve  60  with a force direction opposite to the insertion direction, in which the motor shaft  30 ,  130  is insertable into the socket  64 , on the laminated core  41 . At the other longitudinal end region, the longitudinal end  61 , the insulation sleeve  63  includes a flange body  68 , which protrudes radially outward from the tube portion  63  with respect to the insertion axis S or the longitudinal axis L. 
     The flange body  68  forms a longitudinal stop  68 A with respect to the insertion axis S and is supported, for example, on the end side  44  of the laminated core  41  in the region of the longitudinal end  61 . The flange body  68  includes, for example, reinforcing ribs  69 , which extend from its radial circumference in the direction of the socket  64 , i.e., radially inward toward the insertion axis S. The reinforcing ribs  69  are arranged, for example, on an end side  71  of the flange body  68  facing away from the laminated core  41 . 
     Furthermore, a support stop  70  for the motor shaft  30 ,  130  is provided on the insertion opening  64 A, on which a support stop  39 , for example a step, of the motor shaft  30 ,  130  can strike with a force direction parallel to the insertion axis S. The support stop  70  is formed, for example, by a step between the end side  71  of the insulation sleeve  60  and the socket. 
     The insulation sleeve  60  preferably has a smaller outer circumference or diameter in the region of the longitudinal end  62  or on the outlet opening  64 B than in the region of the longitudinal end  61 . For example, insertion bevels  72  are provided on the longitudinal end  62 , which facilitate the insertion of the insulation sleeve  60  into the shaft through-opening  42  of the laminated core  41 . The longitudinal end  62  is designed, for example, as an insertion projection. 
     Preferably, the insulation sleeve  60  protrudes at the longitudinal end  62  with a tube portion  73  forming an insulation portion  76  from the end side  44  of the laminated core  41 , so that electrical insulation is provided there between the motor shaft  30 ,  130 , on the one hand, and the sheets  43 , on the other hand. 
     In contrast, at the other longitudinal end  61 , the flange body  68 , which more or less protrudes or projects laterally from the shaft through-opening  42 , ensures electrical insulation and also forms an insulation portion  76 . Therefore, for example, an electrical insulation distance of, for example, approximately 8 mm to 10 mm, for example an air and creep distance, which is capable of electrical insulation with respect to the voltage P 1 , results both in the region of the flange body  68  and also on the tube portion  73 . 
     A twist-lock contour  74  to engage in the twist-lock contour  47  of the laminated core  41  is preferably arranged on the radial outer circumference of the insulation sleeve  60 , in particular over the entire longitudinal extension of the tube portion  63 . The twist-lock contour  74  is designed, for example, as a twist-lock projection  74 A, in particular as a longitudinal projection or a longitudinal rib  74 B, which extends in parallel to the insertion axis S or rotational axis D. 
     The insulation sleeve  60  is accommodated in a clamp fit or press fit between the motor shaft  30 ,  130  and the laminated core  41 . A friction lock is thus implemented. 
     In addition, a form fit is also provided by the twist-lock contours  47 ,  74 , by means of which the insulation sleeve  60  is held in a formfitting manner on the laminated core  41  with respect to and/or transversely to the rotational axis D. 
     The formfitting contour  36 ,  136  of the motor shaft  30 ,  130  engages like teeth in the inner circumference of the tube portion  63 , so that the motor shaft  30 ,  130  is also accommodated in the insulation sleeve  60  twist-locked with respect to its rotational axis D or longitudinal axis L and/or displacement-fixed with respect to the rotational axis D or the longitudinal axis L. The formfitting contour  36 ,  136  advantageously forms a counter formfitting contour on the inner circumference of the tube portion  36 , thus, for example, plastically deforms the inner circumference of the tube portion  63 , so that the formfitting contour  36 ,  136  is engaged in a formfitting manner with this counter formfitting contour. The plastic deformation or embossment of the counter formfitting contour results or forms, for example, during the insertion of the motor shaft  30 ,  130  into the insulation sleeve  60 . 
     The insulation sleeve  60  thus enables the motor shafts  30 ,  130 , which can be inserted directly without additional measures into the laminated core  141 , to also be readily usable with the laminated core  41 . Different motor shafts thus do not have to be constructed. The motor shafts  30 ,  130  are geometrically identical at the holding portions  33 , which are provided for the connection to the laminated cores  41  or  141 . For example, length and diameter of the holding portions  33  are identical. However, it is possible that different surfaces and/or surface contours are provided in the region of the holding portions  33  of the motor shaft  30  and  130  for the respective optimum hold of the laminated core  41  or  141 . 
     Buttress projections  43 A protruding in the shaft through-opening  42  or  142  preferably penetrate into the radial outer circumference of the tube portion  63  of the insulation sleeve  60  or the radial outer circumference of the holding portion  33  of the motor shaft  30 ,  130 . For example, formfitting sections  75 A, thus, for example, formfitting receptacles  75 B, form on the insulation sleeve  60 , in which the buttress projections  43 A engage, schematically indicated in  FIG. 5 . The radial outer circumference of the tube portion  63  is displaced radially outward with respect to the insertion axis S or the rotational axis D, for example, by the motor shaft  30 , wherein the buttress projections  43 A penetrate into the tube portion  63  and preferably claw themselves therein. 
     The buttress projections  43 A are provided, for example, on the end sides of the sheets  43  facing toward the shaft through-opening  42  or  142 . Intervals, for example angular intervals and/or longitudinal intervals, are preferably provided between the buttress projections  43 A, in particular between groups of buttress projections  43 A, with respect to the rotational axis D. The buttress projections  43 A hold the insulation sleeve  60  in the shaft through-opening  42  or the motor shaft  30 ,  130  in the shaft through-opening  142  in parallel to the rotational axis D and/or in the circumferential direction with respect to the rotational axis D. Multiple buttress projections  43 A are preferably provided at angular intervals around the rotational axis D. The insulation sleeve  60  is displaced radially outward by the motor shaft  30  inserted therein, so that the buttress projections  43 A penetrate, in particular penetrate in a claw-like manner, into the outer circumference or the jacket or the circumferential wall  66  of the insulation sleeve  60 . 
     The rotors  40 ,  140  of the drive motors  20 ,  120  can be used together with a stator  80 , which includes an excitation coil assembly  86 . The excitation coil assembly  86  can include differently designed excitation coils  87 , for example excitation coils  87  having more or fewer turns, having different conductor cross sections, or the like, in order to be suitable for the different voltages P 1  and P 2  and/or amperages of currents which flow through the excitation coils  87 . 
     The stator  80  includes a laminated core  81  having a rotor receptacle  82  designed as a through-opening for the rotor  40 ,  140 . The rotor  40 ,  140  is rotatably accommodated in the rotor receptacle  82 , wherein a narrow air gap is provided in a way known per se between the laminated core  81  and the laminated core  41 ,  141 . 
     The laminated core  81  includes sheets  83 , for example electrical sheets or transformer sheets, the plate plane of which extends transversely to the rotational axis D of the drive motor  20 ,  120 . The respective motor shaft  30 ,  130  protrudes from end sides  84 ,  85  of the laminated core  81 , where it is rotatably mounted on bearings  24 ,  25  of a bearing assembly  24 A. 
     The bearings  24 ,  25  are held on bearing receptacles  23  by bearing covers  21 ,  22 , which frontally close the stator  80 . 
     The bearings  24 ,  25  can be inserted, in particular pressed, into the bearing receptacles  23  of the bearing covers  21 ,  22 . However, it is also possible that the bearings  24 ,  25  are extrusion coated or potted using the material of the bearing covers  21 ,  22 . 
     For example, the bearing covers  21 ,  22  are permanently connected to the laminated core  41  or a carrier body  90  carrying the laminated core  41 , for example screwed on, adhesively bonded, or preferably welded. 
     The bearing covers  21 ,  22  and the carrier bodies  90  are preferably made of plastic, in particular of a thermoplastic. The same plastic, for example the same thermoplastic, is preferably used for the bearing covers  21 ,  22  and the carrier bodies  90 . 
     For example, the carrier body  90  is produced in a casting method, during which the laminated core  81  is potted. 
     The carrier body  90  includes bearing cover receptacles  91  for the bearing covers  21 ,  22 . For example, circumferential walls  26  of the bearing covers  21 ,  22  are insertable, for example with their end sides, into the bearing cover receptacles  91 . 
     The bearing cover  21  is arranged closer to the output portion  34  of the motor shaft  30 ,  130 . The bearing cover  22  on the region more remote therefrom. The bearing covers  21 ,  22  close the laminated core  81  on longitudinal end regions opposite to one another. The bearing cover  21  protrudes less from the end side of the laminated core  41 ,  141  than the bearing cover  22 . The bearing cover  21  includes a receptacle space  21 A for the flange body  68 . 
     The bearing  24  is closer to the potentially current-conducting laminated cores  41 ,  81  than the bearing  25 . 
     The bearing  24  and the bearing  25  are electrically conductively connected to the bearing portion  31  and thus the motor shaft  30 ,  130 , so that as such the hazard exists that a voltage from the excitation coil assembly  86  will jump over to the motor shaft  30 ,  130 . 
     However, a sufficient electrical insulation distance is provided by the electrically insulating flange body  68 , so that this hazard no longer exists. 
     The bearing  25 , in contrast, has a greater longitudinal distance with respect to the rotational axis D to the end side of the laminated cores  41 ,  81 , so that the hazard of an electrical flashover from, for example, the excitation coil assembly  86  to the motor shaft  30 ,  130  also does not threaten here in the region of the bearing  25 . Moreover, the electrically insulating tube portion  73  of the insulation sleeve  60 , which protrudes from the laminated core  41  in the direction of the bearing cover  22 , ensures sufficient electrical insulation. 
     The coil conductors  88  of the excitation coils  87  extend in the laminated core  81  through grooves  89 , which are arranged, for example, in parallel to the rotational axis D or obliquely inclined thereto. The grooves  89  have insertion openings  89 D, which are open to an inner circumference  82 A of the rotor receptacle  82 . The grooves  89  extend between the end sides  84 ,  85 . The coil conductors  88  can be introduced into the grooves  89  through the insertion openings  89 D and, for example, wound around winding heads or winding hammers of the laminated core  81 . 
     The portions of the laminated core  81  facing toward the rotor receptacle  82  of the stator  80 , which are located between the grooves  89 , are covered by an inner lining  92 , for example extrusion coated using plastic, but the grooves  89  are initially open, so that the coil conductors  88  can be laid therein. 
     The excitation coils  87  are furthermore wound around support projections  93  on the end side  84  of the stator  80 , which more or less form winding heads. 
     On the opposite end side  85 , support projections  94  are provided, which are also suitable for wrapping with coil conductors of excitation coils, but in some embodiments are not wrapped. 
     The end side  85  more or less represents the connection side of the drive motor  20 ,  120 . Electrical connecting units  100  are provided there, to which, for example, connecting lines  15  for the electrical connection to the energizing unit  206 ,  306  are connectable or connected. The connecting lines  15  include a plug connector for plugging onto an energizing unit  206 ,  306 . The connecting units  100  can also be referred to as terminals. 
     The connecting lines  15  can, for example, be plugged onto the connecting units  100  or also directly soldered thereon. The connecting units  100  include, for example, connecting contact regions  101  designed as contact projections, on which connecting plugs, which are connected to the connecting lines, can be plugged on. Furthermore, holes  102  are provided on the connecting contact regions  101 , through which, for example, a connecting conductor of the connecting lines  15  can be led through and soldered to the connecting unit  100  or electrically connected in another way. For example, welding of such a connecting conductor to the connecting unit  100  would also be readily possible. 
     The connecting units  100  can be arranged using a plug installation on the carrier body  90 . The carrier body  90  includes holders  95  for the connecting units  100 . The holders  95  comprise sockets  96 , into which the connecting units are insertable. The sockets  96  are provided between receptacle projections  97 , which protrude from the end side  85  of the carrier body  90 . For example, the receptacle projections  97  have grooves  98  opposite to one another, into which insertion projections  104  protruding laterally from the connecting units  100  are insertable, for example like a tongue-and-groove connection. 
     The insertion projections  104  protrude laterally from a base body  103  of a respective connecting unit  100 . The insertion projections  103  protrude transversely to the longitudinal extension of the connecting contact region  101  from the base body  103 . The insertion projections  104  and the connecting contact region  101  overall form an approximately T-shaped configuration. For example, the base body  104  more or less forms a base leg, from which the insertion projections  104  protrude laterally like lateral legs. However, the base planes of the insertion projections  104  and the base body  103  are different. A transition section  106 , which includes, for example, S-shaped curves or arc sections or curves or arc sections opposite to one another, is provided between the base body  103  and the insertion projections  104 . Therefore, the insertion projections  104  thus protrude from a rear side  115  of the base body  103 . 
     At the free end regions protruding from the base body  103 , the insertion projections  104  have formfitting contours  105 , in particular gear teeth  105 A, barbs, or the like, using which a formfitting hold in the socket  96  is possible. The insertion projections  104  can preferably more or less claw into the socket  96  of the carrier body  90  by means of the formfitting contours  105 . In particular, melting of the carrier body  90  in the region of the sockets  96 , in particular the grooves  98 , upon heating of the connecting unit  100 , which is also described hereinafter, has the result that a formfitting connection is established, on the one hand, between the insertion projections  104 , in particular the formfitting contours  105  thereof, and, on the other hand, the material of the carrier body  90  in the region of the socket  96 , in particular in the region of the grooves  98 . 
     The gear teeth  105 A include, for example, an interlacing, i.e., for example, a tooth  105 B protrudes from the insertion projection transversely to the main plane of the insertion projection  104 . 
     The connecting units  100  include conductor receptacles  107  for accommodating the respective portion of a coil conductor  88  to be connected. The conductor receptacles  107  are formed between, on the one hand, the front side  114  of the base body  103  and, on the other hand, a receptacle arm  108  of the connecting unit  100 , which is connected by means of a connection portion  109  to the base body  103 . In particular, it is advantageous if the base body  103 , the connection portion  109 , and the receptacle arm  108  are integral. The lateral legs or insertion projections  104  of the base body  103  are preferably also integral with it. An inside of the connection portion  109  facing toward the conductor receptacle  107  forms a receptacle section or a receptacle trough  116 A of the conductor receptacle  107 . 
     The conductor receptacle  107  includes a support surface  107 A and a narrow side  1078  angled thereto in the region of the receptacle trough  116 A. An oblique surface  107 C obliquely inclined to the support surface  107 A and to the narrow side  107 B for supporting the at least one coil conductor  88  is arranged between the narrow side  107 B and the large support surface  107 A. The oblique surface  107 C can be, for example, a chamfer, a curved or arched surface, or the like. In any case, the oblique surface  107 C prevents the coil conductor  88  from resting on a sharp edge. 
     The connecting unit  100  is advantageously embodied as a stamped-bent part, which is first stamped out of a base material and then brought into the above-described form by corresponding shaping. 
     The installation and/or fastening and/or electrical contacting of the coil conductor  88  in the conductor receptacle  107  is structured as follows: 
     The conductor receptacle  107  is initially open, specifically in that the receptacle arm  108  still protrudes far from the base body  103 , see, for example,  FIGS. 12 and 14 . The coil conductor  88  can move down to the bottom  116 , i.e., the inner circumference of the connection portion  109 , of the conductor receptacle  107 , see, for example,  FIG. 12 . However, this configuration is rather undesired, so that the coil conductor  88  is held in a position remote from the bottom  116  of the conductor receptacle  107  by additional support measures, for example by a support  251  of an installation unit  250 . 
     However, the configuration is preferably made so that the carrier body  90  includes a support contour  99 , on which the coil conductor  88  is supported during the installation or during the closing of the connecting unit  100 , see  FIGS. 10 and 11 . The coil conductor  88  thus rests on the support contour  99 , so that it does not touch the bottom  116 . The support contour  99  is provided, for example, on an outside of the receptacle projections  97  facing away from the grooves  98 . For example, the support contour  99  is embodied as a step between the respective receptacle projection  97  and the section of the carrier body  90  from which the receptacle projection  97  protrudes. 
     The position of the coil conductor  88  raised off of the bottom  116  is advantageous for the following closing and welding operation. It is advantageous in particular if coil conductors having smaller cross section are used, for example a coil conductor  88 B ( FIG. 11 ). This coil conductor  88 B can then itself have a distance from the bottom  116 , which heats up significantly during the welding process described hereinafter, if the receptacle arm  108  is moved toward the base body  103 , so that it presses with its free end  113  against the front side  114  of the base body  103 . 
     The coil conductor  88 B forms, for example, a component of an excitation coil  87 B of an excitation coil assembly  86 B. 
     The receptacle arm  108  has a closing leg  111 , which protrudes at an angle from a middle arm portion  110  of the receptacle arm  108 , on its end region facing away from the connection portion  109 . For example, a curved portion or connection portion  112  is provided between the middle arm portion  110  and the closing leg  111 . The closing leg  111  protrudes from the middle arm portion  110  in the direction of the front side  114  of the base body  103 , so that its free end  113  touches the front side  114  in the closed state of the conductor receptacle  107 , while a distance, which defines the conductor receptacle  107 , is provided between the middle arm portion  110  and the front side  114  of the base body  103 . 
     A welding gun  252  of the installation unit  250  is used for closing the connecting units  100  and welding. The welding gun  252  includes gun arms  253 ,  255 , on the free end regions of which, which are provided for the contact with the connecting unit  100 , support surfaces  254 ,  256  are provided. The free end regions of the gun arms  253 ,  255 , which are provided to engage with the connecting unit  100 , taper to a point, thus form points  257 . In particular in the case of the gun arm  253 , which has a supporting effect with its support surface  254  on the rear side  115  of the connecting unit  100 , this pointed, narrow design of the gun arm  253  is advantageous. 
     The gun arms  253 ,  254  are arranged in a V shape, so that the points  257  engage from sides opposite to one another on the connecting unit  100  (see  FIG. 16 ), close it, and subsequently weld it. 
     Longitudinal axes L 1 , L 2  of the gun arms  253 ,  255  preferably extend at an angle W, in particular approximately 20° to 40°. Thus, in particular the point  257  of the gun arm  253  can enter the intermediate space between bearing cover  22  and rear side  115  of the connecting unit  100  and support the base body  103  there with its support surface  254 . 
     The gun arm  254  acts in terms of closing the conductor receptacle  107  on the receptacle arm  108 . For example, the curved portion 112  presses against the support surface  256  of the gun arm  255 . The support surfaces  254 ,  256  are oriented in parallel or essentially in parallel to one another when the support surface  254  moves toward the support surface  256 , which is shown as the feed movement VS in the drawing. Therefore, the gun arm  253  thus remains stationary and supports the connecting unit  100  on the rear side, while the gun arm  255  adjusts the receptacle arm  108  in the direction of the base body  103 . Its free end  113  of its closing leg  111  then comes into contact with the front side  114  of the base body  103  of the connecting unit  100 . The conductor receptacle  107  is therefore closed and a receptacle eye  119 A is formed. 
     It is also possible that a welding gun or similar other milling device reshapes the receptacle arm  108  from an initially elongated, linear shape, in which the closing leg  111  is not yet formed, for example, into a receptacle arm  108  having closing leg  111 , for example on the basis of a schematically indicated deformation contour  259  on the gun arm  255 . 
     The gun arms  253 ,  255  are then energized by an energizing unit  258  in that the gun arms  253 ,  255  have different potentials and thus generate a current flow through the connecting unit  100 . 
     The welding current IS flows through the more or less ring-shaped closed connecting unit  100 , i.e., through the sections of the connecting unit  100  which close the conductor receptacle  107 , namely the base body  103  in the region of the conductor receptacle  107  and the receptacle arm  108 . The welding current IS flows via connection regions  118  and  119 , namely, on the one hand, via the connection portion  109 , but also, on the other hand, via a contact region  117  between the free end  113  of the closing leg  111  and the front side  114  of the base body  103 . A large amount of heat occurs both in the contact region  117  and also in the region of the bottom  116 , which does not damage the coil conductors  88  or  88 B, however, because they have a distance to the bottom  116 , but also to the upper contact region  117 . Nonetheless, the connecting unit  100  becomes sufficiently hot in the region of the conductor receptacle  107  that a paint or other similar insulation of the coil conductors  88  melts and they come into electrical contact with the surfaces of the connecting unit  100 . 
     The connecting unit  100  is therefore more or less mechanically closed and subsequently welded to those coil conductors  88  which are accommodated in the conductor receptacle  107 . The installation is, on the one hand, protective for the coil conductors  88 , but, on the other hand, also reliable and highly durable, namely because the coil conductors  88  can be somewhat mechanically changed by the above-mentioned pressing process and the welding process, but are not weakened or changed in their cross sectional geometry in such a way that they break, for example, during the operation of the drive motor  20 ,  120 . 
     When the excitation coils  87  are inserted in the grooves  89 , they are closed by groove covers  180 . 
     The groove covers  180  include a profile body  181 . The groove covers  180  preferably consist of plastic and/or an electrically insulating material. The profile body  181  is embodied, for example, as a plastic part or plastic wall body. 
     The profile body  181  forms a wall body  182  which more or less represents a closure wall for a respective groove  89 . 
     The groove cover  180  or the profile body  181  has a long design and extends along a longitudinal axis L 8 , which extends in parallel to a longitudinal axis L 9  of the groove  89 , when the groove cover  180  is installed in the groove  89 . Longitudinal narrow sides or long sides  195  of the groove cover  180  extend along the longitudinal axis L 8 . The longitudinal sides  195  have a transverse distance Q transversely to the longitudinal axis L 8 . 
     Longitudinal end regions  183  of the groove cover  180  preferably protrude from the laminated cover  81  up to the carrier body  90 , so that electrical insulation is provided over the entire length of a groove  89 . Adhesive bonding, welding, or similar other fastening on one or both of the bearing covers  21  or  22  is advantageous there, for example. 
     The groove cover  181  includes a wall section  184 , which completely covers the groove  88  transversely to the longitudinal axis L 8 . The wall section  184  is approximately U-shaped or arched in cross section, thus transversely to the longitudinal axis L 8 , and forms formfitting projections  186  on its transverse end regions, thus transversely to the longitudinal axis L 8 , which are provided to engage in formfitting receptacles  89 B of the grooves  89 . Transversely to the longitudinal axis L 8 , the groove cover  180  includes two formfitting receptacles  186 , which form sections of the groove cover  180  protruding farthest transversely to the longitudinal axis L 8  and/or are opposite to one another. The formfitting projections  186  and the formfitting receptacle  89 B form formfitting contours  185 ,  89 A, which hold the groove cover  180  in the groove  89  transversely to the longitudinal axis L 8 , which simultaneously represents the longitudinal axis of the groove  89 . 
     The wall section  184  forms a trough -shaped formation between the formfitting contours  185 , and thus has a bottom  187 . The bottom  187  is, for example, bulging into the respective groove  89 , thus extends therein. Of course, a reverse configuration would also be possible, in which the wall section  184  does not protrude radially outward with respect to the rotational axis D, but rather radially inward. However, it would possibly be in the way of the rotor  40 ,  140  there. 
     Lateral legs  188  extend away from the wall section  184 . The lateral legs  188  are inclined toward one another, i.e., their free end regions remote from the wall section  184  are inclined toward one another. The lateral legs  188  and the wall section  184  in the transition region to the lateral legs  188  thus form the formfitting contour  185 , which is V-shaped in a side view, thus a formfitting projection  186 . 
     The installation of the groove cover  180  is structured as follows: 
     As such, it would be possible to insert the groove cover  180  into a respective groove  89 , for example, from one of the end sides  84  or  85 , i.e., along an insertion axis which extends in parallel to the rotational axis D. However, the formfitting contours  185  are movable toward one another transversely to the longitudinal axis L 8 , so that a transverse distance Q between the formfitting contours  185  can be reduced, so that the groove cover  180  can be pushed into the groove  89  past a side edge  89 C of the groove  89 , see  FIGS. 21 to 23  in this regard. In this case, the wall section  184  slides with its rounded outside  189 , thus on its side opposite to the bottom  187 , which thus forms a displacement contour  189 A, past the side edges  89 C, wherein the wall section  184  yields flexibly, in this regard thus forms a flexible section  194 . At the same time, the lateral legs  188  and the formfitting contours  185  are moved toward one another in terms of narrowing the transverse distance Q and finally at the end of this insertion movement SB, the groove cover  180  locks in the groove  89 , i.e., the formfitting contours  185  engage with the formfitting contours  89 A. 
     The groove cover  180  is then accommodated in a formfitting manner in the groove  89 , namely in two directions orthogonal to one another transversely to the longitudinal axis L 8 . 
     A surface of the formfitting receptacle  89 B facing away from the rotor receptacle  82  forms an engage-behind contour  89 E. A surface of the formfitting receptacle  89 B facing toward the rotor receptacle  82  forms a support contour  89 F. 
     The engage-behind contour  89 E and/or the support contour  89 F are preferably planar. 
     The engage-behind contour  89 E and/or the support contour  89 F preferably support the groove cover  180  over its entire longitudinal axis L 8 . 
     The lateral legs  188  include engage-behind surfaces  188 A, which are supported on the engage-behind contour  89 E. Sections of the wall portion  184  adjoining the lateral legs  188  include support surfaces  188 B or form these support surfaces, which are supported on the support contours  89 F. Therefore, the engage-behind contours  89 A support the groove cover  180  in the direction of the interior of the rotor receptacle  82  or the rotational axis D and the support contours  89 F in opposition thereto, thus in the direction radially outward with respect to the rotational axis D or a bottom of the respective groove  89 . 
     The advantage of this construction method also results in that, for example, the carrier body  90  can protrude somewhat radially inward in the direction of the rotor receptacle  82  at the longitudinal end regions of the groove  89  when the groove covers  180  are installed. This is because the longitudinal end regions  183  thereof can then be brought into engagement behind in the direction of the rotor receptacle  82  of the protruding section of the carrier body  90 . 
     Furthermore, the engage-behind surfaces  188 A and the engage-behind contours  89 E as well as the support surfaces  188 B and the support contours  89 F press flatly against one another, so that a sealed seat or a seal of the groove  89  is implemented and/or the groove cover  180  seals closed the groove  89 . 
     The groove covers  180  advantageously have a seal function for sealing off the grooves  89 , but no support function for the excitation coils  87  of the excitation coil assembly  86 . The oblique inclination of the engage-behind contours  89 E and the engage-behind contours  188 A rather even acts in terms of a release bevel, which, upon an application of force to the groove cover  180  in a direction out of the groove  89  or radially inward with respect to the rotational axis D, causes a deformation or narrowing of the groove cover  180  and thus facilitates or enables its release from the groove  89 . 
     An alternative exemplary embodiment according to  FIG. 23B , which is only schematically shown, provides, for example, a groove  489  designed alternatively to the groove  89 , into which a groove cover  480  is introduced. The groove cover  480  includes formfitting receptacles  486  on its longitudinal narrow sides, which are engaged with formfitting projections  489 B of the groove  489 . The formfitting projections  489 B are opposite to one another. The formfitting receptacles  486  and the formfitting projections  489 B are complementary to one another, for example V-shaped. 
     Surfaces of the formfitting projections  489 B facing away from the rotor receptacle  82  form engage-behind contours  489 E. Surfaces of the formfitting projections  489 B facing toward the rotor receptacle  82  form support contours  489 F. The engage-behind contour  489 E and/or the support contour  489 F are preferably planar. The engage-behind contour  489 E and/or the support contour  489 F preferably support the groove cover  480  over its entire longitudinal axis L 8 . The long sides of the groove cover  480  or the formfitting receptacles  486  include engage-behind surfaces  488 A, which are supported on the engage-behind contours  489 E. The formfitting receptacles  486  furthermore include support surfaces  488 B or form these support surfaces, which are supported on the support contours  489 F. 
     The mechanical structure of the stator  80  is preferably entirely or partially identical for both voltage levels P 1  and P 2 . In particular, the rotor receptacle  82  for the rotor  40 ,  140  is identical, thus, for example, has the same diameter. The design of the grooves  89 , thus, for example, their formfitting contours  89 A and/or their width and/or depth are also identical. It is also advantageous if the groove cover  180  is usable or used on the stator  80  independently of whether the excitation coil assembly  86  is designed and/or arranged for the voltage P 1  or the voltage P 2 . An extensive equivalent part principle is thus implementable. 
     It is possible to provide the groove covers  180  as individual profile parts, i.e., that they already have the elongated design shown in  FIG. 20  and have lengths corresponding to the length of the groove  89 . 
     However, one advantageous embodiment provides that the groove covers  180  are obtained from a roll material  190 . The roll material  190  is provided, for example, as a coil  191 . The coil  191  is rotatably accommodated on a coil carrier  273 , for example, in particular a corresponding holding stand. An unwinding device  274  unwinds the roll material  190  from the coil  191 . 
     A portion  192  of the roll material  190  unwound from the coil  191  passes through, for example, a roll assembly  275  having one or more rolls, in particular deflection rolls or guide rolls. 
     Downstream of the roll assembly  275 , a smoothing unit  276  is provided, in which the portion  192  is smoothed, so that its originally rounded formation on the coil  191  is transferred into an elongated formation. The smoothing unit  276  comprises, for example, at least one pressing element  277 , in particular pressing elements  277  opposite to one another, and/or a heating device  278  having heating bodies  279 , in order to bring the roll material  190  of the portion  192  into an elongated formation, as shown in  FIG. 20 . The roll material  190  is thus brought by the smoothing unit  276  into a linear elongated shape. 
     A cutting unit  280  adjoins the smoothing unit  276 , using which a length is cut to length in each case from the portion  192 , which corresponds to a desired groove cover  180 , thus, for example, the length of the laminated core  81  or the carrier body  90 . The cutting unit  280  includes, for example, cutting elements  281 , in particular cutters, blades, sawing elements, or the like. 
     It is to be noted at this point that instead of the laminated core  181  or stator  80 , other, i.e., shorter or longer stators can be provided with groove covers by means of the installation unit  270 . Respective suitable groove covers  180  are thus produced as needed, the length of which is adapted to the length of the stator to be equipped. The cutting element  280 , for example a blade cutter, thus cuts off a groove cover  180  in each case from the portion  192 , which is then grasped by a holding element  271  and inserted in the stator  80 . 
     The holding element  271 , for example a gripper, comprises holding arms  272 , which can grasp the profile body  181  or the groove cover  180  on its longitudinal end regions  183  and can insert it into the groove  89  by means of the insertion movement SB. It would readily be possible that the holding element  271  includes a suction unit or similar holding element, which suctions on the groove cover  180  in the region of the bottom  187  and inserts it with a force component generating the insertion movement SB into the groove  89 . 
     It can thus be seen that by inserting, joining, pressing and the like, essential components of the motor  20 ,  120  are to be produced, namely, for example, the connecting units  100 , the cover of the grooves  89  by means of the groove covers  180 . 
     The magnetization described hereinafter of the magnets  51  also follows this installation concept. 
     This is because the magnets  51  are initially not yet magnetized during the installation on the rotor  40 ,  140  or laminated core  41 ,  141 . A magnetizable material  51 A of a respective magnet body  56  is thus initially not magnetic when the magnet body  52 , which is not yet magnetic as such, is inserted or pressed in the context of an insertion process or pressing process into one of the holding receptacles  45 . The magnetizable material  51 A is, for example, neodymium-iron-boron (NdFeB), advantageously with an additive of dysprosium, or samarium-cobalt (SmCo). 
     For example, support projections  48  are provided on the holding receptacles  45 , which support narrow sides  54  of a respective magnet body  52 . The narrow sides  54  extend in parallel to the rotational axis D in the state of the magnets  50  installed on the rotor  40 ,  140 . The magnet bodies  52  or magnets  51  are preferably clamped between the support projections  48 . 
     Flat sides  53  having larger areas than the narrow sides  54  extend between the narrow sides  54 . Normal directions of the flat sides  53  are preferably radial to the rotational axis D. 
     The laminated cores  41 ,  141  include holding projections  49  for holding the magnet bodies  52 . The holding projections  49  protrude, for example, toward the flat sides  53  and press with their free end regions against the flat sides  53 . It is preferred if the holding projections  49  more or less claw together and/or form buttress projections with the magnet body  52 . 
     The sheets  43  of the laminated cores  41 ,  141  comprise sheets  43  which have recesses  59 A in a predetermined angular position with respect to the rotational axis D. The recesses  59 A preferably extend radially with respect to the rotational axis D away from one of the flat sides of the respective holding receptacle  45 , for example radially inward toward the rotational axis D. It is preferred if the recesses  59 A are arranged in succession in an axial line in parallel to the rotational axis D, thus are aligned with one another. Some of the sheets  43  have holding projections  59  protruding into the recesses. The holding projections  59  furthermore protrude into the insertion cross section of a respective holding receptacle  45 , so that upon insertion of a magnet body  52  into a holding receptacle  45 , they engage with the magnet body  52  and are bent over by the magnet body  52  in an insertion direction SR, in which the magnet body  52  is inserted into the holding receptacle  45 . A holding projection  59  can be displaced here into the recess  59 A of one or more adjacent sheets  43 . An end side of a respective holding projection  59 , which is the width of a narrow side of a sheet  43 , is then supported obliquely inclined on the flat side  53  of the magnet body  52  and prevents the magnet body  52  from being pulled out of the holding receptacle  45  against the insertion direction SR. 
     The magnet bodies  52  or magnets  51  are preferably accommodated in the clamp fit in the holding receptacle  45 . Of course, adhesive bonding, welding, or similar other installation would be entirely possible. The magnetizable material  51 A is thus inserted into the respective laminated core  41 ,  141  in the not yet magnetized state. 
     The rotor  40 ,  140  is then balanced by means of a balancing unit  285 . In this case, the motor shaft  30 ,  130  and possibly the insulation sleeve  60  is already installed. Therefore, the rotor  40 ,  140  can thus be rotated by means of the motor shaft  30 ,  130  around its rotational axis D by means of a motor  286 . A measuring unit  287  establishes, for example, imbalances of the rotor  40 ,  140 . 
     Still existing imbalances are then remedied in that, for example, at least one balancing section  55  is produced, for example, by means of a material-reducing unit  288 , for example a grinding unit, a milling unit, or the like. In this case, for example, material of the laminated core  41 ,  141  is removed where balancing is necessary, wherein chips, metal dust, or the like result. However, this is not problematic since the magnet bodies  52  are not yet magnetized when the material of the laminated core  41 ,  141  is machined. The chips, dust, or the like which result due to removal of the sheets  43  do not magnetically adhere to the laminated core  41 ,  141 , so that they are easily removable. During the later operation of the drive motor  20 ,  120 , no metal chips or dust are thus present, which can damage, for example, the bearings  24  or  25 . 
     It is advantageous if the balancing sections  55  are attached to those regions of the laminated core  41 ,  141  where the laminated core  41 ,  141  has the greatest possible material thickness or thickness in the radial direction with respect to the rotational axis D, i.e., in particular on the radial outside with respect to the magnets  51 . Thus, for example, if an imbalance U occurs at a region unfavorable for producing a balancing section, vectorial balancing is preferred in which the imbalance U is decomposed into force vectors Ux and Uy and, for example, balancing sections  55 x and  55 y are produced corresponding to these vectors by the material-reducing device  288  on the radial outside on the laminated core  41 ,  141 . The balancing sections  55 x and  55 y are located, for example, radially outside on the laminated core  41 ,  141  from holding receptacles  55 , which are arranged at an angular interval in relation to the imbalance U directly adjacent thereto. 
     In the rotor  40 ,  140 , no balancing bodies or balancing weights are necessary on the end sides  44 . Thus, for example, the inflow openings and outflow openings of the air ducts  46  are not covered by balancing weights or balancing bodies. Furthermore, air can also flow laterally past the magnets  51 , namely through air ducts  46 A, which are provided on the holding receptacles  45  or are provided by the holding receptacles  45 . The inflow openings and outflow openings of the air ducts  46 A are also not covered by balancing weights or balancing bodies. 
     A cleaning unit  289 , for example a blowing unit, a brushing unit, and/or a vacuum cleaner or the like, can readily remove the metallic particles resulting during the material removal by the material-reducing unit  288  from the rotor  40 ,  140 , in particular the respective laminated core  41 ,  141 , as long as the magnet bodies  52  are not magnetic. For example, the cleaning device  289  generates an air jet LU, which removes chips and the like from the region of the balancing section  55 . 
     When the rotor  40 ,  140  is balanced, it is magnetized by means of a magnetizing unit  290 , i.e., in particular the magnet bodies  52  are magnetically activated. The magnetizing unit  290  includes, for example, magnetizing heads  291 A,  291  B,  291 C,  291  D. 
     For example, the magnetizing unit  290  comprises a positioning unit  292 , which positions, in particular pivots, the motor shaft  30 ,  130  in such a way that the magnets  51  are exactly opposite to the magnetizing heads  291  at the correct angle. 
     The rotor  40 ,  140  is advantageously positioned by means of a mechanical coding  57  with respect to the magnetizing heads  291 A,  291 B,  291 C,  291 D in such a way that one magnetizing head  291 A,  291  B,  291 C,  291  D is arranged in each case between adjacent magnets  51 . 
     For example, the twist-lock contour  74  is used as the coding  57 , which strikes on a stop  293 , for example, in particular a rotational stop, of the magnetizing device  290 , so that the rotor  40 ,  140  is arranged at the correct rotational angle with respect to the magnetizing heads  291 . The stop  293  is shown in conjunction with the balancing unit  285 . However, other components of the rotor  40  can readily be used as the coding  57 , for example the air ducts  46 , which can engage in corresponding stops of the magnetizing unit  290  and/or which are optically acquirable. An optical acquisition of the rotational angle position of the rotor  40 ,  140  is advantageously also possible, for example by a camera or similar other optical sensor of the magnetizing unit  290 . 
     The magnetizing heads  291 A,  291  B,  291 C,  291  D generate magnetic fields MFA, MFB, MFC, MFD, which penetrate the magnet bodies  52  or magnets  51  arranged adjacent to one another at an angular interval with respect to the rotational axis D so that they are permanently magnetized and form magnetic poles, which are indicated as north poles N and south poles S. The magnetic fields MFA, MFB, MFC, MFD are indicated in dashed field lines having errors corresponding to the magnetic flux direction in the drawing. 
     When the magnets  51  of the rotors  40 ,  140  are magnetized, the rotors  40 ,  140  are installed on the stator  80 . 
     It is obvious that multiple magnet bodies  52  or magnets  51  are also arrangeable in the holding receptacles  45  for the magnets  51 , for example a series arrangement of two or more magnet bodies  52  are magnets  51  in parallel to the rotational axis D. Magnetizing of the respective magnet bodies  52  is also readily possible in this case when they are already accommodated in the holding receptacles  45 . 
     In the case of the magnetizing by the magnetizing device  290 , it is also advantageous that the sheets  43  of the laminated cores  41 ,  141  are magnetically conductive, so that they can optimally conduct the magnetic fields  292  of the magnetizing device  290  through the magnet bodies  52 .