Stator of an electrical machine

Abstract

A stator (1) of an electromachine (2) comprising a stator laminated core (4), wherein the stator laminated core (4) comprises stator teeth (5) and stator slots (6), the stator laminated core (4) includes a number of thin sheet metals (7), the stator slots (6) extend radially between a slot bottom (6g) and a slot head (6h), each stator slot (6) is provided with a conductor bundle (9) to form an electrical stator coil (10), each stator slot (6) has a number of support points (11) to clamp each conductor bundle (9), at least one slot gap (12) is provided between the slot side surface (6f) and the conductor bundle (9) arranged in the stator slot (6), the slot gap (12) forms a slot gap passage (13), and the slot gap passage (13) can be passed through by a coolant along a slot cooling path (14), in the stator (1), - A stator (1) characterized in that each support point (11) is formed by the twisting of individual or multiple thin sheet metal (7) of the stator laminated core (4), - at least one supply path (22) is configured within the stator laminated core (4), and each of these supply paths (22) leads to a stator slot (6) via a slot inlet (23), - within each stator slot (6), two slot cooling paths (14) running in opposite directions are defined, starting from each slot inlet (23), and these slot cooling paths (14) exit as free jets via slot outlets (24) at the end of each stator slot (6).

Description

Technical Field

[0001] The present invention starts with the stator of an electrical machine based on the field of claim 1.

Background Art

[0002] The stator of an electrical machine is already known from DE102019113785A1 and comprises a stator shaft and a stator laminated core. The stator laminated core is configured with stator teeth and stator slots between the stator teeth. The stator laminated core includes a number of thin sheet metals. The stator slots each extend between a slot bottom and a slot head in the radial direction with respect to the stator shaft. In each stator slot, there is provided a conductor bundle containing only one conductor or a plurality of conductors, especially a stack of flat angle conductors, in order to form an electrical stator coil. In each stator slot, a plurality of support points spaced apart from each other in the axial direction with respect to the stator shaft are formed to clamp the conductor or conductor bundle in each stator slot. At least one slot gap is provided between the side surface of each stator slot and the conductor or conductor bundle arranged in the stator slot. The slot gap forms a slot gap path extending in the axial direction. The slot gap path can be traversed by a refrigerant along a slot cooling path. Support points are formed by providing a clamp contour including a plurality of clamp protrusions on special thin sheets called clamp stator sheet metals of the laminated core respectively. These special thin sheets are different from the other thin sheet metals of the laminated core. Each conductor bundle has to be pushed axially into the stator slot with respect to the stator shaft, and in this case, it has to pass through the clamp contour that clamps under the action of a clamping force. At this time, the conductor bundle, especially the electrical insulation part of the conductor bundle, can be damaged.

[0003] From DE102018101640A1, an electrical machine is known in which the stator space is sealed from the rotor space by a tube in the air gap.

Summary of the Invention

[0004] Advantages of the present invention In contrast, the stator according to the present invention having the features of claim 1 has the advantage of being able to create support points without special thin plates and being able to insert the conductor bundle into the stator slot without clamping force when attaching it. This reduces the manufacturing cost of the stator. Moreover, damage to the conductor bundle when inserting it into each stator slot is avoided.

[0005] According to the present invention, this is achieved by the fact that each support point is formed by the twisting of individual or multiple sheets of metal in the laminated core, and in particular by the twisting of one or more groups of sheets of metal.

[0006] A stator according to the present invention having the features of claim 1 has the further advantage that the cooling paths within the stator are simplified with respect to the connection of the flow in the slot gaps or slot cooling paths. The slot cooling paths are part of the direct cooling of the conductor. In particular, there is no need for a ring-shaped distributor to distribute refrigerant to the slot gaps and / or a ring-shaped collector to collect refrigerant coming out of the slot gaps at the end face of the stator laminated core, which may require sealing of the stator space to the rotor space of the electromechanical device, for example, sealing using sleeves or tubes in the gaps. The flow connection according to the present invention in the slot gaps further allows for lower pressures in the cooling paths, thereby reducing the requirement for sealing of the slot gaps. Not only that, since each cooling path runs only in the axial portion of each stator slot rather than along its entire length, the pressure loss in each cooling path is reduced.

[0007] This is achieved, according to the present invention, by configuring at least one supply path within the stator stacked core, which is defined for supplying coolant to slot cooling paths and each leads to a stator slot via a slot inlet, and by defining two slot cooling paths running in opposite directions within each stator slot, starting from each slot inlet, which exit as free jets through slot outlets at the ends of each stator slot, particularly within the slot head or slot bottom.

[0008] At least some of the slot outlets are positioned such that, for example, each coil end of a stator coil is wetted by its respective free jet and thus cooled. Each coil end of a stator coil may, in addition to this, be sprayed by a cooling fluid atomized or injected from a cooling passage of the rotor or housing of the electromechanical device for further improvement of coil end cooling.

[0009] The measures described in the dependent claims enable advantageous modifications and improvements to the stator presented in claim 1. In one advantageous embodiment, each slot cooling path is narrowed at least at a support location, and in this regard, one bypass is provided at each support location, thereby guiding the refrigerant to pass alongside each narrowed support location, and these bypasses for each stator slot are intended to be configured alternately within the slot bottom or within the slot head, from each slot inlet along each slot cooling path, in particular to form a meandering slot cooling path. This improves the cooling of the conductor or conductor bundle within each stator slot.

[0010] It is also advantageous if the first bypass of each stator slot, viewed from the slot inlet in the direction of flow, is located within the slot head. This creates the first meandering section within each slot cooling path, thereby improving the cooling of the conductor or conductor bundle.

[0011] It is highly advantageous if each slot inlet leads to the slot bottom of each stator slot, particularly in the axial center of the stator slot. This ensures that the conductor or conductor bundle within each stator slot is cooled uniformly along its axial extension.

[0012] It is even more advantageous if each slot entrance within each stator slot is located between two support points, and the axial distance between these support points is smaller than the distance between other adjacent support points. This allows the conductor on the side of a conductor bundle that does not face the bottom of the slot to be better cooled in the slot entrance region.

[0013] According to the first flow control configuration, all stator slots may be defined with slot cooling paths of the same trajectory. Alternatively, according to the second flow control configuration, in the same stator, a first set of stator slots may be defined with a first slot cooling path, and a second set of stator slots may be defined with a second slot cooling path running radially opposite to the first slot cooling path. Slot cooling paths running radially opposite but in the same axial direction have bypasses on the radially opposite side at support points in the same axial position, that is, one slot cooling path has a bypass in the slot bottom and the other slot cooling path has a bypass in the slot head.

[0014] According to the first flow control configuration, coolant can be supplied to two slot cooling paths running in opposite directions for each stator slot by a single common slot inlet according to the first embodiment, or by two separate slot inlets separated from each other by one of the support points according to the second embodiment. For example, the first embodiment may be defined for a system with an even number of support points for each stator slot, and the second embodiment may be defined for a system with an odd number of support points for each stator slot.

[0015] According to the second flow control configuration, refrigerant may be supplied to the first slot cooling path of the first set of stator slots via the first slot inlet, and to the second slot cooling path of the second set of stator slots via the second slot inlet. In this case, an axial misalignment is defined between the axial directions of the first and second slot inlets, and in particular, one support point is provided. This creates slot cooling paths that run radially on opposite sides within the stator.

[0016] It is particularly advantageous if the stator slots are closed by at least one slot cap to seal the slot cooling path. It is advantageous that the stator slots may have slot slits within the slot head. According to the first slot cap configuration, a thin plate-shaped slot cap, in particular a slot liner, may be provided as an independent element within each slot slit. Alternatively, in the second slot cap configuration, a single sleeve-shaped or tubular slot cap may be manufactured as an independent element to close all the slot slits. This ensures that the slot cooling path is sealed as tightly as possible to the air gap. An advantage of the slot liner configuration is that these slot liners are not located within the air gap of the electromechanical system. This partial placement of the slot caps would be disadvantageous as it would enlarge the air gap.

[0017] According to the third slot cap configuration, each slot cap can be formed by a tooth tip bridge portion, which is part of a thin sheet metal and connects the tooth tips of adjacent stator teeth, and in particular has reduced magnetic permeability. This has the advantage that the slot cap is achieved without additional parts and is not placed within the gap of the electromechanical unit.

[0018] A further advantage is that each slot cap has multiple axially spaced sealing sections for each slot cooling path, and these sealing sections extend in particular to the conductor or conductor bundle, and a passage is formed between adjacent sealing sections of the same stator slot as a bypass for each slot cooling path. This allows for the creation of a bypass within or on the surface of the slot cap for flow around the support location according to the present invention.

[0019] It is advantageous that each bypass within the slot head may be formed by a recess in the slot cap that is lower than the adjacent sealing portion of the same stator slot, or alternatively by one or two notches in the slot side at the root of the stator tooth tip. The recess in the slot cap may be, for example, a notch, a molded portion, or a curved portion.

[0020] It is advantageous that each bypass within the slot bottom may be formed by one or two notches on the side of the slot at the root of the stator tooth, or by one notch within the slot bottom.

[0021] The present invention further relates to an electric machine comprising a stator according to the present invention and a rotor, the rotor being arranged within a cylindrical rotor space, and the stator being arranged within a stator space which circumscribes the rotor space in an annular manner. According to the present invention, the stator space and the rotor space are not spatially separated from each other, and thus are not sealed from each other. Thereby, the refrigerant in the slot cooling path, especially the cooling fluid, can be easily received and collected within the sump section. For example, there is no need for a seal between the stator space and the rotor space using a so-called tube within the gap, and thus the manufacturing cost of the electric machine is reduced. In particular, there is no need for a ring-shaped distributor and / or a ring-shaped collector on the end face of the stator laminated core, and this ring-shaped distributor and / or ring-shaped collector surrounds one of the coil ends of the stator coil for its cooling, is sealed with respect to the rotor space, and is provided for distributing the refrigerant to the slot gap path or collecting the refrigerant coming out of the slot gap path.

[0022] Exemplary embodiments of the present invention are schematically shown in the drawings and will be explained in more detail in the following description.

Brief Description of the Drawings

[0023] [Figure 1] It is a partial view of the stator according to the present invention of the electric machine. [Figure 2] It is a cross-sectional view of one of the stator slots of the stator based on FIG. 1, having a conductor bundle supported at a plurality of support locations according to the present invention. [Figure 3] It is a view of the support location according to the present invention based on FIG. 2. [Figure 4] It is a cross-sectional view along line IV-IV of FIG. 2 of the first embodiment of the stator based on FIGS. 1 and 2, having a slot cooling path according to the present invention with one common slot inlet. [Figure 5] It is a cross-sectional view along line IV-IV of FIG. 2 of the second embodiment of the stator based on FIGS. 1 and 2, having a slot cooling path according to the present invention with one common slot inlet. [Figure 6]Cross-sectional view along line IV-IV of FIG. 2 of a third embodiment of a stator having a slot cooling path according to the present invention with separate slot inlets. [Figure 7] FIG. showing one stator slot of a first set of stator slots of a stator having a slot cooling path according to the present invention with one common slot inlet, according to a fourth embodiment. [Figure 8] FIG. showing one stator slot of a second set of stator slots of a stator having a slot cooling path according to the present invention with one common slot inlet, according to a fourth embodiment. [Figure 9A] Cross-sectional view along line IX-IX of FIG. 4 of an embodiment of a stator provided with a sleeve-shaped slot cap. [Figure 9B] Cross-sectional view along line IX-IX of FIG. 4 of an embodiment of a stator provided with a thin plate-shaped slot liner as a slot cap. [Figure 9C] Cross-sectional view along line IX-IX of FIG. 4 of an embodiment of a stator provided with a tip bridge portion as a slot cap. [Figure 10A] Cross-sectional view along line X-X of FIG. 4 of an embodiment of a stator provided with a sleeve-shaped slot cap. [Figure 10B] Cross-sectional view along line X-X of FIG. 4 of an embodiment of a stator provided with a thin plate-shaped slot liner as a slot cap. [Figure 10C] Cross-sectional view along line X-X of FIG. 4 of an embodiment of a stator provided with a tip bridge portion as a slot cap. [Figure 11A] Cross-sectional view along line XI-XI of FIG. 4 of an embodiment of a stator provided with a sleeve-shaped slot cap. [Figure 11B] Cross-sectional view along line XI-XI of FIG. 4 of an embodiment of a stator provided with a thin plate-shaped slot liner as a slot cap. [Figure 11C]This is a cross-sectional view along line XI-XI in Figure 4 relating to one embodiment of a stator having a tooth-tip bridge portion as a slot cap. [Figure 12] This figure shows an electromachine including a stator and a rotor according to the present invention. [Modes for carrying out the invention]

[0024] Figure 1 shows a partial view of a stator according to the present invention for an electromachine. The stator 1 of the electric machine 2 according to the present invention has a stator shaft 3 and a stator laminated core 4, the stator laminated core 4 comprising stator teeth 5 and stator slots 6 between the stator teeth 5, the stator laminated core 4 comprising a number of thin sheet metals 7. The stator teeth 5 of the stator 1 are interconnected, for example, via a stator yoke 20. Within each stator slot 6 is provided a conductor bundle 9 containing one or more conductors 8, particularly a stack of flat wire conductors, to form an electric stator coil 10. In Figure 1, for the sake of simplicity, a conductor bundle 9 is shown in only one of the stator slots 6. Each conductor 8 has an insulating coating, not shown.

[0025] The stator slot 6 extends radially with respect to the stator shaft 3 between a slot bottom 6g facing the stator yoke 20 and a slot head 6h opposite to the slot bottom 6g. The slot head 6g is the radial portion of the stator slot 6 opposite to the slot bottom 6g, and this slot head is located, for example, in the region of the innermost radial conductor 8 of the conductor bundle 9, and may also include the slot slit 6s of the stator slot 6.

[0026] Figure 2 shows a cross-sectional view of one of the stator slots of a stator based on Figure 1, which has a conductor bundle supported at multiple support points according to the present invention. Within each stator slot 6, multiple support points 11 are formed, spaced apart from each other in the axial direction with respect to the stator shaft 3, to clamp and hold the conductor 8 or conductor bundle 9 located within each stator slot 6.

[0027] Figure 3 shows a diagram of the support points according to the present invention based on Figure 2. According to the present invention, each support point 11 is intended to be formed by the twisting of individual or multiple thin sheet metal 7 of the stator laminated core 4, in particular by the twisting of one group 17 or multiple groups 17 of the thin sheet metal 7.

[0028] These twisted sheet metals 7 are twisted (in the opposite direction) around the stator axis 3 at, for example, a specific twist angle φ relative to the other sheet metals 7 of the stator laminated core 4 in order to form one of the individual support points 11. Each support point 11 is formed by two groups 17 of sheet metals 7 twisted in opposite directions at, for example, a specific twist angle φ around the stator axis 3, as shown in Figure 3. Between the support points 11 according to the present invention, the conductors 8 or conductor bundles 9 of each stator slot 6 are suspended in mid-air, that is, supported without contacting the stator laminated core 4. In other words, the conductors 8 or conductor bundles 9 of each stator slot 6 are in contact with the stator laminated core 4 only at the support points 11.

[0029] The reverse twisting of the sheet metal 7 to form each support point 11 creates support sections of the sheet metal 7, and these support sections protrude into each stator slot 6 from opposite sides of each stator slot 6, so that the conductors 8 or conductor bundles 9 between the support sections are clamped at the clamping surface of the conductors 8 or conductor bundles 9. Each conductor 8 or conductor bundle 9 in each stator slot 6 may have at least one raised protective layer 15 at the clamping surface of each support point 11. The twisted sheet metal 7 is fixed against further twisting within the stator laminated core 4, for example, by material bonding joints of the sheet metal 7, particularly by welding.

[0030] At least one slot gap 12 is provided between the slot side surface 6f of each stator slot 6 and the conductor 8 or conductor bundle 9 disposed within the stator slot 6, and the slot gap 12 forms a slot gap passage 13 that extends in the axial direction. Each slot gap passage 13 is permeable to a cooling fluid, such as oil, along the slot cooling path 14, and is configured on both sides of the conductor 8 or conductor bundle 9 facing both slot side surfaces 6f.

[0031] Figure 4 shows a first embodiment of a stator based on Figures 1 and 2 having a slot cooling path according to the present invention with one common slot inlet, in a cross-section along line IV-IV in Figure 2.

[0032] Furthermore, according to the present invention, at least one supply path 22 is configured within the stator laminated core 4, which is intended to supply coolant to the slot cooling path 14 and to lead to the stator slots 6 via slot inlets 23. Each supply path 22 runs radially within the stator laminated core 4, at least at the end facing the respective slot inlet 23.

[0033] According to the present invention, within each stator slot 6, two slot cooling paths 14 running in opposite directions are defined, starting from each slot inlet 23, and these slot cooling paths 14 exit as free jets through slot outlets 24 at the ends of each stator slot 6, particularly within the slot bottom 6g or within the slot head 6h.

[0034] Each slot cooling path 14 is narrowed at least at the support points 11, and in this regard, one bypass 18 is provided at each support point 11, thereby guiding the refrigerant to pass alongside each narrowed support point 11. The bypass 18 of each stator slot 6 is configured alternately within the slot bottom 6g or the slot head 6h along the respective slot cooling path 14 from the respective slot inlet 23, thereby resulting in a meandering trajectory of the slot cooling path 14.

[0035] The first bypass 18 in each stator slot 6, viewed from the slot inlet 23 in the direction of flow, is provided, for example, within the slot head 6h. Each slot inlet 23 leads to the slot bottom 6g of each stator slot 6, particularly in the axial middle section of each stator slot 6, and especially in the axial center.

[0036] According to the first embodiment of the stator 1, a distance d in the same axial direction is defined between adjacent support points 11. According to the first flow control configuration, the same trajectory of slot cooling path 14 can be defined for all stator slots 6. An example of such a trajectory is shown in Figure 4.

[0037] Figure 5 shows a second embodiment of the stator according to Figures 1 and 2, having a slot cooling path with one common slot inlet, in a cross-section along line IV-IV in Figure 2.

[0038] According to the second embodiment of the stator 1, each slot inlet 23 of each stator slot 6 is located between two support points 11, and the axial distance d between these support points 11 is smaller than the distance d between other adjacent support points 11.

[0039] Figure 6 shows a third embodiment of the stator according to Figures 1 and 2, having a slot cooling path with separate slot inlets, in a cross-section along line IV-IV in Figure 2.

[0040] As shown in Figures 4 and 5, a slot cooling path 14 with one common slot inlet 23 is defined for each stator slot 6. Alternatively, a slot cooling path 14 with separate slot inlets 23 can be created for each stator slot 6. The separate slot inlets 23 are separated from each other, for example, by a support point 11.

[0041] Figure 7 shows one stator slot of a first set of stator slots in a stator according to Figures 1 and 2, which has a slot cooling path according to the present invention with one common slot inlet, according to a fourth embodiment.

[0042] Figure 8 shows one stator slot of a second set of stator slots in a stator based on Figures 1 and 2, which has a slot cooling path according to the present invention with one common slot inlet, according to a fourth embodiment.

[0043] According to the second flow control configuration, in the same stator 1, a first set 32.1 of stator slots 6 may have a first slot cooling path 14.1 based on Figure 7, and a second set 32.2 of stator slots 6 may have a second slot cooling path 14.2 running radially on the opposite side, based on Figure 8. The slot cooling paths 14 running radially on the opposite side have a bypass 18 on the radially opposite side at support points 11 located in the same axial position, that is, within the slot bottom 6g for one slot cooling path 14.1, 14.2 and within the slot head 6h for the other slot cooling path 14.2, 14.1. The trajectories of these slot cooling paths 14 radially on the opposite side are achieved by the axial displacement X of the slot inlet 23.

[0044] In other words, the first slot cooling path 14.1 of the first set 32.1 of the stator slots 6 has a first slot inlet 23.1, and the second slot cooling path 14.2 of the second set 32.2 of the stator slots 6 has a second slot inlet 23.2. In this case, an axial displacement X is defined between the axial directions of the first and second slot inlets 23.1 and 23.2, and in particular, one support point is provided.

[0045] Each bypass 18 within the slot bottom 6g may be formed, for example, by one or two notches 29 in the slot side surface 6f at the root of the stator tooth 5, or by one notch 29 in the slot bottom 6g, based on Figures 9A, 9B, and 9C.

[0046] The stator slots 6 of the stator 1 are closed by at least one slot cap 25 to seal the slot cooling path 14. The stator slot 6 may have slot slits 6s within the slot head 6h. According to the first slot cap configuration, a thin plate-shaped slot cap 26, in particular a slot liner, may be provided as an independent element within each slot slit 6s. Alternatively, according to the second slot cap configuration, a single sleeve-shaped or tubular slot cap 27 may be manufactured as an independent element to close all the slot slits 6s.

[0047] Alternatively, according to the third slot cap configuration, each slot cap 25 can be formed by a metal tooth tip bridge portion 28, which is part of a thin sheet metal 7 and connects the tooth tips 5h of adjacent stator teeth 5, and in particular has reduced magnetic permeability. The reduced magnetic permeability of the tooth tip bridge portion 28 can be achieved, for example, by heat treatment or cold working of the tooth tip bridge portion 26.

[0048] Each slot cap 25 has a plurality of axially spaced sealing portions 19 for each slot cooling path 14. These sealing portions 19 extend, in particular, to the conductors 8 or conductor bundles 9. Axial passages 18 are formed between adjacent sealing portions 19 of the same stator slot 6, serving as bypasses 18 for each slot cooling path 14.

[0049] Figures 10A, 10B, and 10C show one of the sealing portions 19 of each slot cap 25 for three different slot cap configurations. Each bypass 18 within the slot head 6h can be formed by recesses fabricated within slot caps 25, 26, and 27 according to the slot cap configuration, based on Figures 11A, 11B, and 11C, where these recesses are lower than adjacent sealing portions 19 of the same stator slot 6. The recesses within the slot cap 25 may be, for example, notches, molded portions, curved portions, or grooves.

[0050] Alternatively, or in addition to the above, each bypass 18 within the slot head 6h according to Figure 11B may be formed by one or two notches 30 within the slot side surface 6f at the root of the tip 6h of the stator tooth 6.

[0051] Figure 12 shows an electromachine including a stator 1 and a rotor 35 according to the present invention. The rotor 35 is located within a cylindrical rotor space 36, and the stator 1 is located within a stator space 37 that surrounds the rotor space 36 in a ring shape.

[0052] According to the present invention, the stator space 37 and the rotor space 36 are not spatially separated.

Claims

1. A stator (1) of an electromachine (2) having a stator shaft (3) and a stator laminated core (4), wherein the stator laminated core (4) is configured with stator teeth (5) and stator slots (6) between the stator teeth (5), the stator laminated core (4) includes a number of thin sheet metal (7), the stator slots (6) extend radially with respect to the stator shaft (3) between a slot bottom (6g) and a slot head (6h), respectively, and within each stator slot (6) is provided a conductor bundle (9) including one conductor (8) or multiple conductors (8), particularly a stack of flat wire conductors, for forming an electrical stator coil (10), and the stator slot Within (6), a plurality of support points (11) are formed to clamp the conductor (8) or conductor bundle (9) located within each of the stator slots (6), and at least one slot gap (12) is provided between the slot side surface (6f) of each of the stator slots (6) and the conductor (8) or conductor bundle (9) located within the stator slot (6), and the slot gap (12) forms a slot gap passage (13) extending in the axial direction, and the slot gap passage (13) can be permeated by a coolant, particularly oil, along a slot cooling path (14) in the stator (1), - Each of the support points (11) is formed by the twisting of individual or multiple thin sheet metal (7) of the stator laminated core (4), particularly by the twisting of one or more groups of thin sheet metal (7), - At least one supply path (22) is configured within the stator stacked core (4), the supply path (22) is defined for supplying refrigerant to the slot cooling path (14), and each leads to the stator slot (6) via a slot inlet (23), - Within each of the stator slots (6), two slot cooling paths (14) running in opposite directions are defined, starting from each slot inlet (23), and the stator (1) is characterized in that the slot cooling paths (14) exit as free jets through slot outlets (24) at the end of each of the stator slots (6), particularly within the slot head (6h) or within the slot bottom (6g).

2. The stator according to claim 1, characterized in that each of the slot cooling paths (14) is narrowed at least at the support location (11), and in this regard, one bypass (18) is provided at each of the support locations (11) so that the refrigerant is guided to pass beside each of the narrowed support locations (11), and the bypass (18) of each of the stator slots (6) is configured to form a particularly meandering slot cooling path (14), and is alternately located within the slot bottom (6g) or within the slot head (6h) from each of the slot inlets (23) along each of the slot cooling paths (14).

3. The stator according to claim 2, characterized in that the first bypass (18) of each stator slot (6), viewed from each slot inlet (23) in the direction of flow, is provided within the slot head (6h).

4. The stator according to any one of claims 1 to 3, characterized in that each of the slot inlets (23) is connected to the slot bottom (6g) of each of the stator slots (6) in the axial middle section of each of the stator slots (6), particularly in the axial center.

5. The stator according to any one of claims 1 to 4, characterized in that each slot entrance (23) within each stator slot (6) is located between two support points (11), and the axial spacing (d) of the support points (11) relative to each other is smaller than the spacing (d) of other adjacent support points (11).

6. a. All stator slots (6) have the same trajectory slot cooling path (14), or b. The stator according to any one of claims 1 to 5, characterized in that a first set (32.1) of stator slots (6) is provided with a first slot cooling path (14.1), and a second set (32.2) of stator slots (6) is provided with a second slot cooling path (14.2) running on the radially opposite side.

7. The stator according to 6a, characterized in that a coolant can be supplied to the two slot cooling paths (14) running in opposite directions for each stator slot (6) by one common slot inlet (23) or by two separate slot inlets (23) separated from each other by one of the support locations (11).

8. The stator according to 6b, wherein a coolant can be supplied to the first slot cooling path (14.1) of the first set (32.1) of the stator slots (6) via the first slot inlet (23.1), and to the second slot cooling path (14.2) of the second set (32.2) of the stator slots (6) via the second slot inlet (23.2), and in this case, an axial displacement (X) is defined between the axial directions of the first and second slot inlets (23.1, 23.2), and in particular, one support location (11) is provided.

9. The stator slot (6) is closed by at least one slot cap (25) to seal the slot cooling path (14), a. The stator slot (6) has slot slits (6s) within the slot head (6h), and within each slot slit (6s), thin plate-shaped slot caps (26), particularly slot liners, are provided as independent elements, or a single sleeve-shaped or tubular slot cap (27) is manufactured as an independent element to close all the slot slits (6s), or b. The stator according to any one of claims 1 to 8, characterized in that each slot cap (25) is formed by a tooth tip bridge portion (28), the tooth tip bridge portion (28) is part of one of the thin sheet metal (7), connects the tooth tips (5h) of adjacent stator teeth (5), and in particular has reduced magnetic permeability.

10. The stator according to claim 9, characterized in that each of the slot caps (25) has a plurality of axially spaced sealing portions (19) for each of the slot cooling paths (14), the sealing portions (19) in particular extending to the conductor (8) or the conductor bundle (9), and a passage is formed between adjacent sealing portions (19) of the same stator slot (6) as a bypass (18) for each of the slot cooling paths (14).

11. Each of the bypasses (18) within the slot head (6h) a. By the recess in the slot cap (25) that is lower than the adjacent sealing portion (19), or b. The stator according to any one of claims 2 to 10, characterized in that it is formed by one or two notches (30) in the slot side surface (6f) at the root of the tooth tip (5h) of the stator tooth (5).

12. Each of the aforementioned bypasses (18) within the slot bottom (6g) a. By one or two notches (29) in the slot side surface (6f) at the root of the stator tooth (5), or b. The stator according to any one of claims 2 to 11, characterized in that it is formed by a notch (29) in the bottom of the slot (6g).

13. An electric machine comprising a stator (1) according to any one of claims 1 to 12 and a rotor (35), wherein the rotor (35) is arranged in a cylindrical rotor space (36) and the stator (1) is arranged in a stator space (37) that surrounds the rotor space (36) in a ring shape, characterized in that the stator space (37) and the rotor space (36) are not spatially separated.

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