Stator of an electric machine

Abstract

The invention relates to a stator of an electric machine having a stator body, on which stator teeth and stator grooves are formed and which comprises a stator yoke, wherein the stator grooves each have a first groove base facing the stator yoke, wherein a respective conductor or a conductor bundle for forming a stator winding is provided in the stator grooves, wherein a respective spacer element (15) is provided in the stator grooves, which forms at least one groove gap (16), through which a cooling fluid can flow along a groove cooling path (17), wherein the spacer element (15) comprises a central strip (15m), on the long side edges of which a respective flank strip (15f) is angled, said flank strip facing one of the tooth flanks (5f) of the respective stator groove (6), wherein flank recesses (20) for forming a groove gap channel are formed in the flank strips (15f) of the respective spacer element (15), characterized in that the flank strips (15f) of the respective spacer element (15) each have a rectangular strip contour (25) and the flank recesses (20) of the spacer element (15), in both flank strips (15f), are each arranged at a distance (A) from the strip contour (25) towards at least three sides of the strip contour (25) and are closed in the radial direction facing away from the central strip (15m).

Description

[0001] R. 415159-3

[0002] 1

[0003] Description

[0004] title

[0005] Stator of an electric machine

[0006] State of the art

[0007] The invention relates to a stator of an electrical machine according to the preamble of the main claim.

[0008] A stator for an electric machine is already known from CN118353183 A. The stator has a stator shaft and a stator body, in particular a stator lamination stack, on which stator teeth and stator slots located between the stator teeth are formed, and which includes a stator yoke connecting the stator teeth. The stator slots each have a first slot base facing the stator yoke and a second slot base arranged opposite the first slot base. A conductor or a bundle of conductors, in particular a stack of flat wire conductors, is arranged in each stator slot to form an electrical stator winding. Furthermore, each stator slot includes an electrically insulating spacer element that establishes a distance between the conductor or bundle of conductors and the tooth flanks of the respective stator slot and extends in the axial direction.The spacer element is a folded body made of insulating paper, comprising a central strip located at the first or second groove base, on whose long side edges a flank strip facing one of the tooth flanks of the respective stator groove is angled to form a fold edge, wherein the flank strips of the respective spacer element have flank recesses to form groove gap channels between the tooth flanks and the conductor or conductor bundle, wherein the stator grooves can be permeated by a cooling fluid, in particular oil, via the groove gap channels.

[0009] The spacer element can easily become tilted during axial insertion into the stator slot. R. 415159-3

[0010] 2

[0011] Advantages of the invention

[0012] In contrast, the stator of an electric machine according to the invention with the characterizing features of the main claim has the advantage that the spacer element has a higher stiffness and is easier to insert into the stator slots, in that the flank strips of the respective spacer element each have a rectangular strip contour and the flank recesses of the spacer element in both flank strips are arranged at a distance from the strip contour to at least three, in particular all, sides of the strip contour and are closed in a radial direction away from the central strip.

[0013] The spacer element according to the invention is easier to insert into the stator slots because there are fewer or no edges between its axial ends that could jam or become wedged in the stator slot. The design according to the invention allows U-profiles to be formed radially inside and / or radially outside the flank recesses of the respective spacer element, extending in the axial direction and providing higher stiffness.

[0014] The measures listed in the dependent claims enable advantageous further developments and improvements of the stator of an electrical machine specified in the main claim.

[0015] According to a fifth embodiment, the flank recesses of the respective spacer element in the respective flank strip can be positioned without a gap to one longitudinal side, in particular a longitudinal side facing the central strip, of the strip contour. This improves the cooling of the radially innermost or radially outermost conductor in the respective stator slot.

[0016] It is particularly advantageous if, according to a first to fourth embodiment, the flank recesses of the respective spacer element extend only within the respective flank strip, or, according to a fifth embodiment, extend beyond the respective flank strip into an edge region of a narrow side, in particular the central strip, of the spacer element. Both alternatives result in high rigidity of the respective spacer element and easy assembly of the spacer element. R. 415159-3

[0017] 3

[0018] According to the first alternative, the central strip and / or end strip of the respective spacer element are neither narrowed nor interrupted by the flank recesses. According to the second alternative, the cooling of the radially innermost or radially outermost conductor in the respective stator slot can be improved.

[0019] It is also advantageous if the flank recesses of the respective spacer element are closed in the axial direction. The flank recesses of the respective spacer element are thus bounded in the axial direction between the walls of the spacer element.

[0020] Furthermore, it is advantageous if an end strip is bent at each of the side edges of the flank strips facing away from the central strip, forming a folded edge, with the central strip and the end strips of the respective spacer element being arranged opposite each other in the radial direction with respect to the stator axis. This increases the stiffness and stability of the respective folded spacer element, making it easier to insert the spacer elements axially into the stator slots. The end strips of the respective spacer element can extend axially at least beyond each flank recess of the respective flank strip, and in particular, they can extend over the entire axial length of the respective spacer element.

[0021] It is highly advantageous if the central strip of the respective spacer element is connected at its ends to the end strips of the spacer element via four sleeve sections arranged in pairs, forming two fully enclosed end sleeves. At least one flank recess of the flank strip is provided between the sleeve sections of the respective flank strip. The flank recesses of the respective spacer element are thus closed in the axial direction towards the end of the stator groove.

[0022] Furthermore, it is advantageous if the end sleeves of the respective spacer element are at least partially located in the respective stator slot. In this way, the cooling fluid cannot leave the stator slots directly via the flank recesses. R. 415159-3

[0023] 4

[0024] It is further advantageous if the flank recesses of the respective spacer element are arranged opposite each other in the two flank strips, in particular if they are mirror-symmetrical. In this way, the conductors of the respective stator slot are cooled on both sides at the same axial position, thereby improving the cooling of the stator winding.

[0025] Furthermore, it is advantageous if the respective spacer element is folded from expandable insulating paper, wherein the expandable insulating paper comprises an expandable material that is particularly suitable for fixing the stator winding in the stator slot by expansion and that is particularly thermally activatable. In this way, the stator winding can be fixed by the spacer elements of the stator slots, especially in the area of ​​the end sleeves of the spacer elements. In addition, the spacer elements provide slot gap channels for direct conductor cooling.

[0026] Furthermore, it is advantageous if at least one, and in particular both, flank strips of the respective spacer element have at least one axial group, and in particular an axial pair, of flank recesses arranged one behind the other in the axial direction, between which a radial separating web extends in the radial direction, connecting in particular the central strip of the spacer element with one of the end strips. This improves the fixation of the stator winding, since the radial separating web provides an additional support point for fixing the stator winding, especially in the case of expandable insulating paper. Because the stator winding oscillates with a reduced amplitude due to this additional support point, the fill factor in the stator slots can be increased, thereby achieving higher efficiency and a higher maximum power output of the electric machine.Furthermore, the flank recesses of an axial group of flank recesses can be hydraulically separated, i.e., not flow-connected, by the radial separating web connecting the central strip to one of the end strips. This allows for more uniform direct cooling of the conductors in the flank recesses of the axial group.

[0027] It is advantageous if the radial separating web is designed to guide the flow of the cooling fluid from a recess inlet to an axially spaced recess outlet of the respective flank recess, in particular at least one guide ramp extending at an oblique angle to the axial direction R. 415159-3

[0028] 5, in particular, has two guide ramps towards both flank recesses. In this way, uniform cooling can be achieved within the respective flank recess.

[0029] Furthermore, it is advantageous if the radial separating web has a longitudinal axis that runs at an oblique angle to the axial direction. In this way, two flank recesses can be supplied with cooling fluid by means of a recess inlet that extends radially across the radial separating web in a tooth flank of the respective stator groove.

[0030] It is further advantageous if at least one, and in particular both, flank strips of the respective spacer element have several radially arranged flank recesses, especially axial groups of flank recesses arranged one behind the other in the axial direction. This allows the cooling fluid to be guided even more effectively in the respective flank recess.

[0031] According to an advantageous first embodiment, an axially extending elongated hole can be formed in the central strip of the respective spacer element to form a slot gap channel at the first or second slot bottom of the respective stator slot. In this way, the cooling of the radially innermost or radially outermost conductor in the respective stator slot can be improved.

[0032] According to an advantageous second embodiment of the first embodiment, at least one of the end strips of the respective spacer element can have an axially extending elongated slot to form a slot gap channel at the first or second slot base of the respective stator slot, which is preferably open or closed towards a longitudinal edge of the end strip. In this way, the cooling of the radially innermost or radially outermost conductor in the respective stator slot can be improved.

[0033] It is highly advantageous if at least one groove is formed in the central strip of the respective spacer element, extending in the axial direction and projecting, in particular, away from or towards the conductor bundle. In this way, the stiffness of the respective spacer element can be further increased. The groove R. 415159-3

[0034] 6 of the spacer element can in particular be arranged in a slot of the stator groove, which is formed between adjacent tooth ends, in particular between adjacent tooth heads, of the stator teeth.

[0035] It is further advantageous if at least one of the flank strips of the respective spacer element has a curved pre-mark that extends in the axial direction and is curved towards or away from the conductor or conductor bundle. This further increases the stiffness of the respective spacer element. A curved pre-mark in the flank strip that curves towards the conductor or conductor bundle has the advantage that the spacer element can be inserted more easily into the stator slot.

[0036] The respective spacer element can advantageously have at least one support collar at an axial end for axially supporting the spacer element against an end face of the stator body, which is folded towards an outside of the spacer element, in particular by at least 90 degrees. In this way, a stop is formed on the spacer element, so that the spacer element is brought into a defined position when axially inserted into the stator slot.

[0037] In an advantageous embodiment, the respective spacer element can have at least one insertion collar at its other end, which is angled towards a cavity enclosed by the spacer element and projects axially, thus facilitating the insertion of the spacer element into a stator slot by forming an insertion ramp. In this way, the respective spacer element can be more easily inserted into the respective stator slot.

[0038] In an advantageous embodiment, the two end strips of the spacer element are arranged overlapping on a narrow side of the spacer element, particularly at the bottom of the first groove. In this way, the spacer element can seal or quasi-seal a groove slot towards the air gap, preventing or minimizing the amount of cooling fluid from the stator groove from entering the air gap. Alternatively, the two overlapping end strips can also be located at the bottom of the second groove. R. 415159-3

[0039] 7

[0040] A further advantage arises if, for each flank strip of the respective spacer element, the ratio of the sum of the flank recess areas to the total area (including the flank recess(s)) of the flank strip is greater than 0.5, in particular greater than 0.7, greater than 0.75 or greater than 0.8. This further improves the direct conductor cooling in the respective stator slot.

[0041] In an advantageous embodiment, a central sleeve can be formed between the end sleeves of the respective spacer element, which includes radial separating webs of two flank strips. This further improves the fixation of the stator winding.

[0042] The invention further relates to an electric machine comprising a stator according to the invention, a rotor and an air gap formed between the stator and the rotor.

[0043] drawing

[0044] Exemplary embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description.

[0045] They show:

[0046] Fig. 1 shows a stator of an electrical machine according to the invention.

[0047] Fig. 2 shows a sectional view through one of the stator slots of the stator according to Fig. 1 with a spacer element according to the invention located in the stator slot.

[0048] Fig. 3 shows a cross-section through one of the stator slots along the line III-III in Fig. 2, Fig. 4A shows a first embodiment of the spacer element according to the invention as shown in Fig. 2.

[0049] Fig. 4B shows a development of the first embodiment according to Fig. 4A,

[0050] Fig. 5A shows a second embodiment of the spacer element according to the invention as shown in Fig. 2.

[0051] Fig. 5B shows a development of the second embodiment according to Fig. 5A,

[0052] Fig. 6A shows a third embodiment of the spacer element according to the invention as shown in Fig. 2.

[0053] Fig. 6B shows a development of the third embodiment according to Fig. 6A, R. 415159-3

[0054] 8

[0055] Fig. 7A shows a fourth embodiment of the spacer element according to the invention as shown in Fig. 2.

[0056] Fig. 7B shows a development of the fourth embodiment according to Fig. 7A,

[0057] Fig. 8A shows a fifth embodiment of the spacer element according to the invention as shown in Fig. 2.

[0058] Fig. 8B shows a development of the fifth embodiment according to Fig. 8A,

[0059] Fig. 9 shows a development of a first variant of the first embodiment according to Fig. 4A,

[0060] Fig. 10 shows a development of a second variant of the first embodiment according to Fig. 4A and

[0061] Fig. 11 shows an alternative cross-sectional shape of the spacer element according to the invention.

[0062] Description of the exemplary implementations

[0063] Fig. 1 shows a stator of an electric machine according to the invention.

[0064] The stator 1 of an electric machine 2 has a stator shaft 3 and comprises a stator body 4, in particular a stator laminated core, on which stator teeth 5 and stator grooves 6 lying between the stator teeth 5 are formed and which has a stator yoke 10 connecting the stator teeth 5.

[0065] The electric machine 2 also includes a rotor 30 (Fig. 2). An air gap 31 is formed between the stator 1 and the rotor 30.

[0066] Fig. 2 shows a sectional view through one of the stator slots of the stator according to Fig. 1 with a spacer element according to the invention located in the stator slot.

[0067] In each of the stator slots 6, a conductor 11 or a bundle of conductors 12 comprising several conductors 11, in particular a stack of flat wire conductors, is provided to form an electrical stator winding 14.

[0068] Furthermore, an electrically insulating spacer element 15 extending axially with respect to the stator axis 3 is inserted in each of the stator slots 6, which establishes a distance between the conductor 11 or conductor bundle 12 and the tooth flanks 5f of the respective stator slot 6 and between the tooth flanks 5f R. 415159-3

[0069] 9 and the conductor 11 or conductor bundle 12 forms at least a slot gap 16 which extends in the axial direction with respect to the stator axis 3 and can be permeated by a cooling fluid, in particular oil, as a slot gap channel along a slot cooling path 17.

[0070] The respective spacer element 15 is a folded body made from insulating paper. Insulating paper refers to a conventional electrically insulating sheet insulating material for electrical machines. The insulating paper can, for example, be a laminate.

[0071] The respective spacer element 15 can, for example, have a length in the axial direction that corresponds at least to the length of the stator slots 6.

[0072] Fig. 3 shows a cross-section through one of the stator slots along the line Ill-Ill in Fig. 2.

[0073] The stator grooves 6 each have a first groove base 7 facing the stator yoke 10 and, in particular, a second groove base 8 arranged opposite the first groove base 7. A slot 9 can be formed at the second groove base 8 between adjacent tooth ends of the stator teeth 5, especially tooth tips. In this case, the second groove base 8 can, for example, be formed by two inner surfaces of two adjacent tooth tips facing the respective stator groove 6. Alternatively, adjacent tooth ends of the stator teeth can also be connected by a sheet metal web or a tooth bridge (not shown), so that the stator grooves 6 do not have a slot and are closed radially inwards, i.e., towards the air gap 31. In this case, the second groove base 8 is formed by an inner surface of the respective tooth bridge or sheet metal web.

[0074] The respective spacer element 15 comprises a central strip 15m located at the first or second groove base 7, 8, on the long side edges of which a flank strip 15f, facing one of the tooth flanks 5f of the respective stator groove 6, is bent to form a fold edge. According to the exemplary embodiment, an end strip 15e is bent to form a fold edge on the side edges of the flank strips 15f facing away from the central strip 15m. The central strip 15m and the end strips 15e of R. 415159-3

[0075] The 10 respective spacer elements 15 are arranged opposite each other in a radial direction with respect to the stator axis 3.

[0076] The central strip 15m and the end strips 15e of the respective spacer element 15 are designed without recesses, for example, according to Fig. 4A, Fig. 4B, Fig. 5A, Fig. 5B, Fig. 6A, Fig. 6B, Fig. 7A and Fig. 7B, to facilitate the insertion of the spacer element 15 and to avoid tilting during insertion.

[0077] The flank strips 15m have a strip height that corresponds to the radial height of the stator slots 6, in particular essentially corresponds to the radial height of the stator slots 6. The center strips 15m and the end strips 15e each have a strip height that corresponds to the width of the stator slots 6, in particular essentially corresponds to the width of the stator slots 6.

[0078] In the flank strips 15f of the respective spacer element 15, flank recesses 20 are formed according to Fig. 2 and Fig. 3 to form a groove gap channel.

[0079] In the respective spacer element 15, the two end strips 15e are arranged overlapping on a narrow side of the spacer element 15, which lies particularly at the first groove base 7.

[0080] If two end strips 15e are provided on the respective spacer element 15, they can overlap on one narrow side of the spacer element 15 as shown in Fig. 3. The overlapping end strips 15e can have the same or different wing lengths. Alternatively to overlapping, the two end strips 15e of the respective spacer element 15 can butt against each other or side by side along a joint or slot over their full axial length or at least in the area of ​​the end sleeves 15s.

[0081] Fig. 4A shows a first embodiment of the spacer element according to Fig. 2. Fig. 4B shows a development of the first embodiment according to Fig. 4A.

[0082] According to the invention, the flank strips 15f of the respective spacer element 15 each have a rectangular strip contour 25 and the flank recesses 20 of the spacer element 15 in both flank strips 15f R. 415159-3

[0083] 11 each are arranged at least three, in particular all, sides of the strip contour 25 at a distance A to the strip contour 25 and are closed in a radial direction away from the central strip 15m.

[0084] The flank recesses 20 of the respective spacer element 15 are also closed in a radial direction facing the median strip 15m. The flank recesses 20 of the respective spacer element 15 are therefore closed all the way around their recess edge.

[0085] Each rectangular strip contour 25 has four edge sides that define the strip contour 25 and thus the respective flank strip 15f. The rectangular strip contour 25 has, for example, a length in the axial direction that is at least equal to the length of the stator slots 6. Therefore, the edge sides of the strip contour 25 extending in the axial direction have a length that is at least equal to the length of the stator slots 6. The edge sides of the strip contour 25 extending in the radial direction have the strip height of the flank strip 15f described above.

[0086] The distance A to the strip contour 25 is understood to be the distance of an edge side of the strip contour 25 to a recess edge of the respective flank recess 20 facing the edge side.

[0087] The respective flank strip 15f of the respective spacer element 15 has a straight side edge facing away from the center strip 15m, which is an edge of the rectangular strip contour 25 and on which a fold edge is formed at the transition to the respective end strip 15e.

[0088] According to the first to fourth embodiments, the flank recesses 20 of the respective spacer element 15 extend, for example, only in the flank strips 15f.

[0089] The flank recesses 20 of the respective spacer element 15 are closed in the axial direction. This can be achieved by connecting the central strip 15m of the respective spacer element 15 at the ends of the spacer element 15 to the end strips 15e of the spacer element 15 via four projecting sleeve sections 15k, which are arranged in pairs opposite each other, forming two R. 415159-3

[0090] 12 fully enclosed end sleeves 15s. The end sleeves 15s of the respective spacer element 15 lie, as shown in Fig. 2, at least partially in the respective stator groove 6.

[0091] The respective spacer element 15 can have at least one tab-shaped support collar 28 at an axial end, i.e. at the end sleeve 15s, which is folded towards an outside of the spacer element 15, in particular by at least 90 degrees, and is provided for axial support of the spacer element 15 on an end face of the stator body 4.

[0092] The other end of the spacer element 15 can have at least a tab-shaped insertion collar 29, which projects at an angle in the axial direction and facilitates the insertion of the spacer element 15 into a stator slot 6 by forming an insertion ramp.

[0093] According to Fig4A and Fig.4B, the flank recesses 20 of the respective spacer element are, for example, square-shaped, in particular parallelogram-shaped or trapezoidal.

[0094] In each of the two flank strips 15f of the respective spacer element 15, at least one flank recess 20 is provided. The flank recesses 20 of the respective spacer element 15 are arranged opposite each other in the two flank strips 15f, in particular in a mirror-symmetrical manner and / or in a mirror-symmetrical arrangement.

[0095] The flank recesses 20 are designed, for example, such that each conductor 11 in the respective stator slot 6 is exposed section by section on both sides by the flank recesses 20 for direct conductor cooling.

[0096] For each flank strip 15f of the respective spacing element 15, the ratio of the sum of the flank recess areas to the total area (including the flank recess(s) 20) of the flank strip 15f can be, for example, greater than 0.5, in particular greater than 0.7, 0.75 or 0.8.

[0097] Each flank recess 20 is assigned a recess inlet 21 and a recess outlet 22 according to Fig. 2, each of which is located on a tooth flank 5f of the R. 415159-3

[0098] 13 recesses are formed in the respective stator groove 6. The respective recess inlet 21 can be supplied with cooling fluid via a supply path 18 running through the stator body 4 and is formed in a central section of the respective stator groove 6, viewed in the axial direction, in particular in the axial center of the groove. Two cooling channels 17 running in opposite directions are provided in the respective stator groove 6, which originate from a recess inlet 21 and extend in opposite directions to the ends of the stator groove 6. The respective recess outlet 22 can, for example, be flow-connected via an outlet path 19 running through the stator body 4 to an outlet opening 33 in an end disk 34 of the stator body 4.

[0099] The respective spacer element 15 can be folded from an expandable insulating paper, wherein the expandable insulating paper comprises an expandable material suitable for fixing the stator winding 14 in the stator slot 6 by expansion and which is particularly thermally activatable.

[0100] In the case of a stator lamination stack 4, the lamination plates of the stator lamination stack 4 have lamellar teeth to form the stator teeth 5.

[0101] According to Fig. 3, a sealant 36, in particular an adhesive or a resin, can be applied to the tooth ends or tooth heads of the lamellar teeth facing away from the stator yoke 10 in such a way that the lamellar tooth ends or tooth heads of the stator teeth 5 are impermeable to cooling fluid from one of the stator grooves 6 towards the air gap 31. The sealant 36 can be applied to the respective tooth end or tooth head, for example, over the entire surface or partially over the surface, in particular according to a pattern. The second groove base 8 and any groove slot of the respective stator groove 6 can be sealed by the narrow side of the respective spacer element 15 abutting the second groove base 8.Additionally, by expanding the respective spacer element 15, sealant from the section of the spacer element 15 facing the second groove base 8 can penetrate into the adjacent laminated groove walls of the respective stator groove 6 and contribute to sealing the stator groove 6 to the air gap 31. In this way, a complete seal of the stator's inner circumference can be achieved without a separate stator sleeve. Alternatively, a stator sleeve can also be provided on the stator's inner circumference to seal the stator's inner circumference. R. 415159-3.

[0102] 14

[0103] In at least one of the flank strips 15f, and in particular in both flank strips 15f as shown in Figs. 4A and 4B, of the respective spacer element 15, at least one axial group, in particular an axial pair, of flank recesses 20 arranged one behind the other in the axial direction can be formed, between which a radial separating web 15r extends in the radial direction, in particular connecting the central strip 15m of the spacer element 15 with one of the end strips 15e. The axial group of flank recesses 20 arranged one behind the other in the axial direction is arranged in the respective flank strip 15f in the axial direction between the two sleeve sections 15k.

[0104] The respective radial separating web 15r is arranged in an axial direction between the end sleeves 15s in a central area, in particular in the axial center, of the flank strip 15f of the respective spacer element 15.

[0105] A central sleeve 15t can be formed between the end sleeves 15s of the respective spacer element 15. This central sleeve comprises radial separating webs 15r of two flank strips 15f and is, in particular, completely closed. In the first to fourth embodiments, the respective end sleeve 15s of the respective spacer element 15 is connected to the central sleeve 15t via two U-shaped longitudinal profiles 15L extending axially and arranged on two opposite narrow sides of the spacer element 15. If the central sleeve 15t is absent, the two end sleeves 15s of the spacer element 15 are directly connected to each other via the two longitudinal profiles 15L.

[0106] In the fifth embodiment according to Fig. 8A, the respective end sleeve 15s of the respective spacer element 15 is connected to the central sleeve 15t via a U-shaped longitudinal profile 15L extending in the axial direction and via the strip-shaped central strip 15m. If the central sleeve 15t is absent, the two end sleeves 15s of the spacer element 15 are directly connected on one narrow side via the longitudinal profile 15L and on the other narrow side via a strip-shaped longitudinal profile, in particular the central strip 15m.

[0107] The respective radial separating web 15r is designed according to Fig. 4A and Fig. 4B for guiding the flow of the cooling fluid from a recess inlet 21 to an axially spaced recess outlet 22 of the respective flank recess 20. R. 415159-3

[0108] 15

[0109] In particular, the radial separating web 15r has at least one guide ramp 23 extending at an oblique angle α to the axial direction. According to Fig. 4A and Fig. 4B, the radial separating web 15r has two guide ramps 23 facing both flank recesses 20. The radial separating web 15r is thus cup-shaped or triangular. The guide ramp 23 can, for example, be straight, curved, arched, or arcuate.

[0110] If the respective radial separating web 15r is omitted, at least one flank recess 20 is provided in the respective flank strip 15f of the respective spacer element 15, which extends in the axial direction from one of the two sleeve sections 15k to the other sleeve section 15k.

[0111] Fig. 5A shows a second embodiment of the spacer element according to the invention as shown in Fig. 2. Fig. 5B shows a development of the second embodiment as shown in Fig. 5A.

[0112] According to the second embodiment, the flank recesses 20 of the spacer element 15 are rectangular, and the radial separating webs 15r are also rectangular. The radial separating webs 15r can also be omitted.

[0113] Fig. 6A shows a third embodiment of the spacer element according to the invention as shown in Fig. 2. Fig. 6B shows a development of the third embodiment as shown in Fig. 6A.

[0114] According to the third embodiment, at least one, and in particular both, flank strips 15f of the respective spacer element 15 have several flank recesses 20 arranged one behind the other in a radial direction, and in particular several axial groups of flank recesses 20 arranged one behind the other in a radial direction. An axial separating web 15x is provided between the radially adjacent flank recesses 20 for flow guidance.

[0115] The flank recesses 20 of the spacer element 15 are, for example, rectangular or oblong. R. 415159-3

[0116] 16

[0117] Between adjacent flank recesses 20 of each axial group, the radial separating web 15r runs in a radial direction, which in particular connects the central strip 15m of the spacer element 15 with one of the end strips 15e and is, for example, rectangular in shape.

[0118] Fig. 7A shows a fourth embodiment of the spacer element according to the invention according to Fig. 2. Fig. 7B shows a development of the fourth embodiment according to Fig. 7A.

[0119] According to the fourth embodiment, the respective radial separating web 15r has a longitudinal axis of extension which runs at an oblique angle β to the axial direction, wherein the separating web 15r is, for example, parallelogram-shaped.

[0120] In one of the two flank recesses 20 of the respective flank strip 15f of the respective spacer element 15, the recess inlet 21 opens radially inwards, and in the other flank recess 20 of the flank strip 15f of the spacer element 15, it opens further radially outwards into the respective flank recess 20. In the other of the two flank recesses 20 of the respective flank strip 15f of the respective spacer element 15, the recess inlet 21 and the recess outlet 22 are both located radially inwards or both radially outwards, so that the flank recess 20 has a projection 40 at an edge section located between the recess inlet 21 and the recess outlet 22 for flow deflection in order to achieve uniform cooling in the flank recess 20 in the radial direction.

[0121] Fig. 8A shows a fifth embodiment of the spacer element according to the invention according to Fig. 2. Fig. 8B shows a development of the fifth embodiment according to Fig. 8A.

[0122] The flank recesses 20 of the respective spacer element 15 according to the fifth embodiment are not spaced from one longitudinal side of the strip contour 25 in the respective flank strip 15f, for example, a longitudinal side facing the center strip 15m, so that a strip-shaped longitudinal profile 15L is formed there instead of a U-shaped one. The flank recesses 20 of the spacer element 15 are therefore arranged in both flank strips 15f only on three sides of the strip contour 25 at a distance A from the strip contour 25. In the first to R. 415159-3

[0123] In the fourth embodiment, the flank recesses 20 of the spacer element 15 are arranged in both flank strips 15f at a distance A from the strip contour 25 on all sides.

[0124] According to the fifth embodiment, the flank recesses 20 of the respective spacer element 15 can also extend beyond the respective flank strip 15f into an edge area of ​​a narrow side, for example of the center strip 15m, of the spacer element 15.

[0125] Fig. 9 shows a development of a first variant of the first embodiment according to Fig. 4A.

[0126] According to the first variant of the first embodiment, at least one axially extending elongated hole 40 can be additionally formed in the central strip 15m of the respective spacer element 15 to form a slot gap channel at the first or second slot base 7, 8 of the respective stator slot 6. The elongated hole 40 is to be understood in particular as a recess with a longitudinal extent. The at least one elongated hole 40, like the flank recesses 20, can be supplied with cooling fluid via the supply path 18.

[0127] Fig. 10 shows a development of a second variant of the first embodiment according to Fig. 4A.

[0128] According to the second variant of the first embodiment, at least one axially extending elongated hole 40 can be formed in at least one of the end strips 15e of the respective spacer element 15 to form a slot gap channel at the first or second slot base 7,8 of the respective stator slot 6, which can be designed to be open or closed towards a longitudinal edge of the end strip 15e facing away from the flank strip 15f.

[0129] According to Fig. 10, an open elongated hole 40 is formed in each of the two end strips 15e of the respective spacer element 15, which is to be understood in particular as an open recess with a longitudinal extent. For this embodiment with two open elongated holes 40, it is provided that the two end strips 15e of the respective spacer element 15 lie next to each other in the folded state in the area of ​​the end sleeves 15s without overlapping and, for example, in a butt joint manner, and R. 415159-3

[0130] 18 that the two end strips 15e together form a closed elongated hole 40 between the two end sleeves 15s formed by the two open elongated holes 40.

[0131] If an overlap of the two end strips 15e of the respective spacer element 15 and an elongated hole 40 is to be provided only in one of the two end strips 15e (not shown), the elongated hole 40 can, for example, be provided in the one of the two end strips 15e which is facing towards or away from the nearest uppermost or lowermost conductor 11 of the conductor bundle 12.

[0132] At least one of the elongated holes 40, like the flank recesses 20, can be supplied with cooling fluid via the supply path 18.

[0133] Fig. 11 shows an alternative cross-sectional shape of the spacer element according to the invention.

[0134] On a narrow side of the respective spacer element 15, in particular in the central strip 15m of the respective spacer element 15, at least one groove 24 can be formed which extends in the axial direction and in particular projects away from the conductor 11 or conductor bundle 12 or in particular projects towards the conductor 11 or conductor bundle 12.

[0135] Furthermore, at least one of the two, in particular both, flank strips 15f of the respective spacer element 15 can have a curved pre-embossing 26 which extends in the axial direction and is curved towards the conductor 11 or conductor bundle 12 or curved away from the conductor 11 or conductor bundle 12.

Claims

R. 415159-3 19 Claims 1. Stator of an electric machine (2) with a stator shaft (3) and with a stator body (4), in particular a stator laminated core, on which stator teeth (5) and stator slots (6) located between the stator teeth (5) are formed and which comprises a stator yoke (10) connecting the stator teeth (5), wherein the stator slots (6) each have a first slot base (7) facing the stator yoke (10) and in particular a second slot base (8) which is arranged opposite the first slot base (7), wherein a conductor (11) or a conductor bundle (12) comprising several conductors (11), in particular a stack of flat wire conductors, is provided in each of the stator slots (6) to form an electrical stator winding (14), wherein an electrically insulating spacer element (15) extending in the axial direction with respect to the stator shaft (3) is provided in each of the stator slots (6), which maintains a distance between the conductor (11) orThe spacer element (15) is positioned between the conductor bundle (12) and the tooth flanks (5f) of the respective stator slot (6) and forms at least one slot gap (16) between the tooth flanks (5f) and the conductor (11) or conductor bundle (12), which extends in the axial direction and can be permeated by a cooling fluid as a slot gap channel along a slot cooling path (17), wherein the spacer element (15) is a folded body made of insulating paper, which comprises a central strip (15m) located in particular at the first or second slot base (7, 8), on each of whose long side edges a flank strip (15f), which faces one of the tooth flanks (5f) of the respective stator slot (6), is bent to form a fold edge, wherein flank recesses (20) are formed in the flank strips (15f) of the respective spacer element (15) to form a slot gap channel, characterized in that. - the flank strips (15f) of the respective spacer element (15) each have a rectangular strip contour (25) and - the flank recesses (20) of the spacer element (15) in the respective The flank strips (15f) are arranged at a distance (A) from the strip contour (25) to at least three, in particular all, sides of the strip contour (25) and are closed in a radial direction away from the central strip (15m).

2. Stator according to claim 1, characterized in that the Flank recesses (20) of the respective spacer element (15) in the respective R. 415159-3 20 The flank strips (15f) shall not have a distance to the strip contour (25) on any longitudinal side, in particular on a longitudinal side facing the central strip (15m).

3. Stator according to one of the preceding claims, characterized in that the flank recesses (20) of the respective spacer element (15) extend only in the respective flank strip (15f) or extend beyond the respective flank strip (15f) into an edge region of a narrow side, in particular the middle strip (15m), of the spacer element (15).

4. Stator according to one of the preceding claims, characterized in that the flank recesses (20) of the respective spacer element (15) are closed in the axial direction.

5. Stator according to one of the preceding claims, characterized in that the flank strips are formed on the side edges facing away from the central strip (15m). (15f) each end strip (15e) is angled to form a fold edge, wherein the middle strip (15m) and the end strips (15e) of the respective spacer element (15) are arranged opposite each other in a radial direction with respect to the stator axis (3).

6. Stator according to claim 5, characterized in that the central strip (15m) of the respective spacer element (15) is connected at the ends of the spacer element (15) via four sleeve sections (15k) which are opposite each other in pairs, to the end strips (15e) of the spacer element (15) forming two circumferentially closed end sleeves (15s).

7. Stator according to claim 6, characterized in that the end sleeves (15s) of the respective spacer element (15) lie at least partially in the respective stator groove (6).

8. Stator according to one of the preceding claims, characterized in that the flank recesses (20) of the respective spacer element (15) are arranged in pairs opposite each other in the two flank strips (15f), in particular in a mirror-symmetrical form.

9. Stator according to one of the preceding claims, characterized in that the respective spacer element (15) is made of an expandable insulating paper. R. 415159-3 21 is folded, wherein the expandable insulating paper comprises an expandable material which is particularly suitable for fixing the stator winding (14) in the stator slot (6) by expansion and which is particularly thermally activatable.

10. Stator according to one of the preceding claims, characterized in that at least one, in particular both, flank strips (15f) of the respective spacer element (15) has at least one axial group, in particular an axial pair, of flank recesses (20) arranged one behind the other in an axial direction, between which a radial separating web (15r) extends in a radial direction, which in particular connects the central strip (15m) of the spacer element (15) with one of the end strips (15e).

11. Stator according to claim 10, characterized in that the radial separating web (15r) is designed to guide the flow of the cooling fluid from a recess inlet (21) to an axially spaced recess outlet (22) of the respective flank recess (20), in particular having at least one guide ramp (23) extending at an oblique angle (a) to the axial direction, and especially having two guide ramps (23) towards both flank recesses (20).

12. Stator according to one of claims 10 and 11, characterized in that the radial separating web (15r) has a longitudinal extension axis (27) which runs at an oblique angle (β) to the axial direction.

13. Stator according to one of the preceding claims, characterized in that several flank recesses (20) arranged in a radial direction, in particular axial groups of flank recesses (20), are provided in at least one, in particular both, flank strips (15f) of the respective spacer element (15).

14. Stator according to one of the preceding claims, characterized in that a. in the central strip (15m) of the respective spacer element (15) an axially extending elongated hole (40) is formed to form a slot gap channel at the first or second slot base (7,8) of the respective stator slot (6), or R. 415159-3 22 b. in at least one of the end strips (15e) of the respective spacer element (15) an axially extending elongated hole (40) is formed to form a slot gap channel at the first or second slot base (7,8) of the respective stator slot (6), which is in particular open or closed towards a longitudinal edge of the end strip (15e).

15. Stator according to one of the preceding claims, characterized in that at least one groove (24) is formed in the central strip (15m) of the respective spacer element (15), which extends in the axial direction and in particular projects away from the conductor (11) or conductor bundle (12) or in particular towards the conductor (11) or conductor bundle (12).

16. Stator according to one of the preceding claims, characterized in that at least one of the flank strips (15f) of the respective spacer element (15) has a curved pre-embossing (26) which extends in the axial direction and is curved towards the conductor (11) or conductor bundle (12) or away from the conductor (11) or conductor bundle (12).

17. Stator according to one of the preceding claims, characterized in that the respective spacer element (15) has at least one support collar (28) at an axial end, which is folded towards an outside of the spacer element (15) and is provided for axial support of the spacer element (15) on an end face of the stator body (4).

18. Stator according to claim 17, characterized in that the respective spacer element (15) has at least one insertion collar (29) at the other end, which projects at an angle in the axial direction and facilitates the insertion of the spacer element (15) into a stator groove (6) by forming an insertion ramp.

19. Stator according to one of the preceding claims, characterized in that in the respective spacer element (15) the two end strips (15e) are arranged overlapping on a narrow side of the spacer element (15) which lies in particular on the first groove base (7).

20. Stator according to one of the preceding claims, characterized in that the ratio of the flank strips (15f) of the respective spacer element (15) is determined for each flank strip (15f) of the R. 415159-3 - 23 - The sum of the flank recess areas to the total area of ​​the flank strip (15f) is greater than 0.5, in particular greater than 0.7, greater than 0.75 or greater than 0.

8.

21. Stator according to one of the preceding claims, characterized in that a central spacer (15t) is formed between the end sleeves (15s) of the respective spacer element (15), which comprises radial separating webs (15r) of two flank strips (15f).

22. Electric machine (2) with a stator (1) according to one of the preceding claims. Claims, comprising a rotor (30) and an air gap (31) formed between the stator (1) and the rotor (30).

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