Stator for an electric machine, electric machine having a stator, motor vehicle having an electric machine, and method for cooling a stator

Abstract

The invention relates to a stator (10) for an electric machine (100) for propelling a motor vehicle (K), the stator having: a laminated stator core (20), which has a plurality of individual laminated stator core laminations (22); at least one housing part (60), which surrounds the laminated stator core (20) at least in parts in the circumferential direction (U) of the stator (10); and a cooling device (80), by means of which a cooling medium (12) can be supplied to the stator (10) in order to cool at least parts of the laminated stator core. The laminated stator core (20) comprises at least one rib region (30), the rib region main extent (32) of which is oriented in the longitudinal extent direction (L) of the stator (10) and which has a rib region outer surface (34) which, together with at least one housing inner surface (62), facing the laminated stator core (20) in the radial extent direction (R), of the at least one housing part (60), delimits at least one cooling medium flow gap (36) oriented in the radial extent direction (R) of the stator (10) and provided for the cooling medium (12) to flow through in the circumferential direction (U). The invention also relates to an electric machine (100) having such a stator (10), to a motor vehicle (K), and to a method for cooling a stator (10).

Description

[0001] Stator for an electric motor, electric motor with a stator, motor vehicle with an electric motor and method for cooling a stator

[0002] The invention relates to a stator for an electric machine according to the preamble of claim 1. Further aspects of the invention relate to an electric machine with such a stator, a motor vehicle with an electric machine and a method for cooling a stator.

[0003] From DE 10 2022 202 749 A1, a stator arrangement is known which includes a cooling system designed to cool the stator. For this purpose, the cooling system comprises a cooling jacket surrounding the stator core, which is thermally coupled to the stator core. In particular, the cooling jacket serves to implement fluid cooling, with a coolant flowing through the cooling jacket. The coolant can be a cooling liquid, for example, water or oil. Specifically, the cooling jacket serves to cool the stator core across its entire axial width.

[0004] DE 11 2014 001 340 T5 discloses an electric machine having a stator with a plurality of laminations, each with teeth and cooling openings, arranged around a central opening. When the laminations are stacked to form the stator core, the teeth of adjacent laminations interact to form slots arranged circumferentially around the central opening, which are configured to accommodate a plurality of stator windings. The cooling openings, spaced at angles around the central opening, interact to form cooling manifolds extending along a length of the stator core. One section of the laminations has its cooling openings offset from other laminations in the stack in such a way as to form a plurality of flow paths transverse to the manifolds. The transverse flow paths extend at angles between laminations and adjacent to the manifolds. A head assembly conducts a current into and out of the stator core.

[0005] The object of the present invention is to provide a stator, an electric motor, and a motor vehicle with improved cooling, as well as a method for improved stator cooling. This object is achieved by a stator with the features of claim 1, by an electric motor with the features of claim 9, by a motor vehicle with the features of claim 10, and by a method with the features of claim 11. Advantageous embodiments with expedient further developments of the invention are specified in the dependent claims.

[0006] A first aspect of the invention relates to a stator for an electric motor for powering a motor vehicle, comprising a stator core consisting of a plurality of individual stator core laminations, at least one housing part that surrounds the stator core at least partially in the circumferential direction of the stator, and a cooling device by means of which a cooling medium can be supplied to the stator for at least partial cooling of the stator core. The electric motor can also be referred to as an electric motor or traction motor. The housing part can preferably be designed as a casting, which makes the housing part inexpensive to manufacture and provides good damping properties. The cooling device can, for example, have channels, in particular at least one supply channel and at least one drain channel, by means of which a cooling medium exchange between the stator and its surroundings can take place.

[0007] According to the invention, the stator lamination stack comprises at least one finned area, the main extent of which is oriented in the longitudinal direction of the stator and which has an outer surface that, together with at least one housing inner surface of the at least one housing part facing the stator lamination stack in the radial direction of the stator, defines at least one cooling medium flow gap oriented in the radial direction of the stator and designed for circumferential flow of the cooling medium. The finned area can also be referred to as a web area.

[0008] This is advantageous because, in this stator, the cooling medium can be advantageously guided circumferentially between the housing and the stator lamination stack. As the cooling medium flows through the at least one gap, particularly effective cooling of the stator can occur. This is because especially high flow velocities and, consequently, high heat transfer coefficients occur when the cooling medium flows through the gap, resulting in a particularly high cooling effect and thus overall improved cooling. A turbulent flow of the cooling medium with high heat transfer can therefore be achieved in the gap.In other words, the at least one cooling medium flow gap is arranged in the radial direction between the stator lamination stack and the housing part, i.e., it is bounded in the radial direction by the stator lamination stack on one side and by the housing part on the other. The housing part can preferably be designed as a hollow cylinder, at least partially, preferably for example, more than 75% of its outer contour, and particularly preferably completely, which makes the housing part particularly easy to manufacture.

[0009] Particularly advantageous cooling with acceptable flow losses has been achieved for gap heights (measured in the radial direction) of at least one cooling medium flow gap between 0.5 mm and 3 mm. This includes gap heights of 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, and 3.0 mm, which allow for particularly advantageous cooling. In particular, a gap height of 0.7 mm has proven to be a particularly good compromise between cooling performance and pressure loss.

[0010] The invention is based on the understanding that when coolant flows through stator bodies in their longitudinal direction, only minimal turbulence is generated, resulting in a correspondingly lower cooling effect. In some cases, only laminar coolant flows occur during such longitudinal flow, significantly reducing the cooling effect. To compensate for this, stator bodies known from the prior art require a larger cooling surface area, which in turn necessitates a correspondingly large pressure drop and increased installation space. Compensating for the increased pressure drop, in turn, requires a high-power coolant pump, which, particularly in battery-electric vehicles, leads to a reduction in range.Stator bodies known from the prior art are typically inserted directly into a housing in which cooling channels are cast around a cylindrical bore for receiving the stator body. These channels allow the coolant to be guided along the longitudinal direction of the stator body. Alternatively, stator bodies known from the prior art are inserted into a sleeve element, which may have cooling fins or channels for a coolant on its outer diameter. Together with the housing, the assembly of the stator body forms a cooling channel system through which a cooling medium can be directed along the longitudinal direction of the stator body. It has been found that the aforementioned systems known from the prior art are, on the one hand, complex to manufacture and, on the other hand, offer limited cooling effectiveness.

[0011] The invention addresses this issue because the circumferential flow through at least one cooling medium gap generates particularly high turbulence, resulting in correspondingly high cooling capacity and heat transfer from the stator to the cooling medium, even without additional turbulence-generating structures such as those used in EGR coolers (exhaust gas recirculation coolers) of internal combustion engines. Furthermore, the invention eliminates the need for any incorporation, for example, casting, of cooling channels into the housing component, allowing the housing component to be manufactured with less effort and at a lower weight compared to conventional housings. Additionally, the use of a sleeve element between the housing and the stator lamination stack, which is common in conventional systems, is eliminated, thus also eliminating the need for any sealing of the sleeve element to the housing component.

[0012] In the stator according to the invention, intermediate elements, such as a sleeve between the housing part and the stator lamination stack, can be dispensed with. In other words, the stator can be free of intermediate elements arranged in the radial direction between the housing part and the stator lamination stack, which results in particularly low manufacturing costs.

[0013] In an advantageous embodiment of the invention, at least one inner surface of the housing of at least one housing part is designed, at least in part, as a hollow cylinder inner surface. This allows the housing to be manufactured with particularly low production costs. Advantageously, at least a large portion of the inner housing surface can surround the stator lamination stack in the circumferential and longitudinal directions of the stator as a hollow cylinder inner surface.

[0014] In a further advantageous embodiment of the invention, the cooling device has at least one supply channel which extends radially through the at least one housing part and through which the cooling medium can be supplied to the at least one cooling medium flow gap in the circumferential direction of the stator. This is advantageous because the supply channel extending radially through the housing part allows the cooling medium to flow onto the stator lamination stack at an angle to the longitudinal direction, preferably perpendicular to the longitudinal direction. As a result of this flow, a strong deflection with high heat transfer coefficients and a uniform distribution of the cooling medium along the longitudinal direction of the stator lamination stack can occur.Both contribute to improved cooling of the stator, especially compared to a conservative, end-face airflow or flow through the stator lamination stack.

[0015] In addition to the feed channel, a drain channel of the cooling device can be provided, which can extend in the radial direction through at least one housing part and through which the cooling medium can be discharged from the stator.

[0016] Preferably, the discharge channel can be arranged opposite the feed channel in the radial direction. Particularly preferably, the discharge channel can be arranged at the lowest geodetic point of the stator.

[0017] In a further advantageous embodiment of the invention, the at least one supply channel is arranged in the longitudinal direction in the region of the center of the stator lamination stack. This advantageously contributes to a particularly uniform distribution of the cooling medium, also referred to as coolant, in the longitudinal direction along the stator lamination stack, so that the cooling medium preferably distributes itself in the longitudinal direction along the at least one cooling medium flow gap and can flow circumferentially through the at least one cooling medium flow gap along a large part of its length or along its entire length. Thus, the cooling medium can first distribute itself along the length of the cooling medium flow gap and then flow circumferentially through the cooling medium flow gap.

[0018] In a further advantageous embodiment of the invention, the cooling device comprises at least one indentation arranged on the housing part, into which the at least one supply channel opens and which has an interior space extending at least substantially in the longitudinal direction of the stator and designed to distribute the cooling medium in the longitudinal direction along the at least one fin area. This is advantageous because the indentation and its interior space enable a particularly flow-optimized distribution of the cooling medium in the longitudinal direction, with the interior space facilitating a distribution of the cooling medium in the longitudinal direction along the cooling medium flow gap.In a further advantageous embodiment of the invention, at least a second rib region of the stator lamination stack is provided, which is arranged circumferentially adjacent to the at least one rib region, and at least one groove region of the stator lamination stack extends in the longitudinal direction between the at least one rib region and the at least one second rib region. This is advantageous because the at least one groove region, which can also be generally referred to as a cooling groove, can serve as a distribution channel oriented in the longitudinal direction, so that after the cooling medium has flowed through the at least one cooling medium flow gap, the cooling medium can first be distributed in the longitudinal direction along the groove region before the cooling medium flows circumferentially through a second cooling medium flow gap associated with the at least one second rib region.Overall, this results in a particularly uniform cooling effect in both the longitudinal and circumferential directions of the stator.

[0019] In a further advantageous embodiment of the invention, the groove area comprises an interior space bounded in the radial direction on one side by the stator lamination stack and on the other side by the at least one housing part, which has a greater radial extent than the at least one cooling medium flow gap. This allows the groove area to form a depression for the cooling medium relative to the at least one cooling medium flow gap, within which the cooling medium can distribute itself uniformly in the longitudinal direction before flowing further in the circumferential direction, for example through a second cooling medium flow gap. This advantageously contributes to uniform cooling of the stator.

[0020] In a further advantageous embodiment of the invention, at least one cover element of the stator rests against at least one end face of the stator lamination stack arranged in the longitudinal direction of the stator. This cover element is designed to prevent uncontrolled escape of cooling medium from the at least one cooling medium flow gap in the longitudinal direction. This advantageously prevents unwanted escape of the cooling medium in the longitudinal direction of the stator. The cover element can have at least one opening through which a flow of cooling medium can be directed towards at least one winding head of the stator. This opening can, for example, be designed as a nozzle opening, thus enabling targeted injection of the cooling medium onto the at least one winding head.

[0021] A second aspect of the invention relates to an electric motor for a motor vehicle, with at least one stator according to the first aspect of the invention. In such an electric motor, improved cooling is implemented.

[0022] A third aspect of the invention relates to a motor vehicle with an electric motor according to the second aspect of the invention and additionally or alternatively with a stator according to the first aspect of the invention. In this motor vehicle, the electric motor has improved cooling.

[0023] A fourth aspect of the invention relates to a method for cooling a stator according to the first aspect of the invention and additionally or alternatively an electric machine according to the second aspect of the invention, in which the cooling medium is guided in the circumferential direction of the stator through the at least one cooling medium passage gap. This allows the stator to be cooled in an improved manner.

[0024] The preferred embodiments and their advantages presented with respect to one of the aspects apply accordingly to the other aspects of the invention and vice versa.

[0025] The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combination specified in each case, but also in other combinations or on their own, without leaving the scope of the invention.

[0026] Further advantages, features and details of the invention will become apparent from the claims, the following description of preferred embodiments and the drawings.

[0027] The invention is explained below again using a specific embodiment. This is illustrated by:

[0028] Fig. 1 shows a schematic representation of a motor vehicle and an electric motor, also called a drive motor or traction motor, which is designed to drive the motor vehicle, wherein the electric motor has a stator shown in schematic sectional view with a stator lamination stack which has a plurality of stator lamination stack individual laminations, with at least one housing part which surrounds the stator lamination stack at least partially in the circumferential direction of the stator and with a cooling device by means of which a cooling medium can be supplied to the stator for at least partial cooling of the stator lamination stack;

[0029] Fig. 2 shows an enlarged view of an area A outlined in dashed lines in Fig. 1, which illustrates that the stator lamination stack comprises rib areas whose main rib area extent is oriented in the longitudinal direction of the stator and which each have a rib area outer surface that together with at least one housing inner surface of the at least one housing part, together with at least one housing inner surface of the at least one housing part facing the stator lamination stack in the radial direction, defines at least one cooling medium flow gap oriented in the radial direction of the stator and provided for flow with the cooling medium in the circumferential direction;

[0030] Fig. 3 shows a further enlarged view of area A, in which arrows illustrate the flow of cooling medium through the stator for cooling the stator during its intended use in the electric motor, in particular during ferry operation of the vehicle; and

[0031] Fig. 4 shows a schematic perspective view of the stator, where the flow of the cooling medium is illustrated at a cutout on at least one housing part of the stator.

[0032] Fig. 1 shows a schematic representation of a motor vehicle K with an electric motor 100, which serves as a traction motor to drive the motor vehicle. In addition to other components, such as windings and a rotor (not shown), the electric motor 100 also has a stator 10. For the sake of clarity, the stator 10 is only partially shown; for example, the windings arranged on the respective stator teeth 14 are not depicted. The stator 10 comprises a stator core 20, which has a plurality of individual stator core laminations 22. The individual stator core laminations 22 are arranged one behind the other in the longitudinal direction L of the stator 10.A stator lamination stack end face 26 is formed by a stator lamination stack single sheet 22 located furthest outwards in the longitudinal direction L, at which the stator lamination stack 20 terminates in the longitudinal direction L and abuts a cover element 90. The cover element 90 can be designed as an annular disk, as can be seen from Fig. 4.

[0033] The stator lamination stack 20 is surrounded by a housing part 60 of the stator 10, which surrounds the stator lamination stack 20 in the circumferential direction U of the stator 10 and extends in the longitudinal direction L over the entire length of the stator lamination stack 20.

[0034] A cooling medium 12 can be supplied to the stator 10 for cooling the stator lamination stack 20 by means of a cooling device 80 of the stator 10.

[0035] The stator lamination stack 20 comprises several circumferentially adjacent rib sections 30, 40, which form radially outer regions of the stator lamination stack 20 in the circumferential direction U. By way of example, 36 rib sections 30, 40 are provided here, which are evenly distributed in the circumferential direction U. In the following, reference is made only to a first rib section 30 and a second rib section 40 arranged circumferentially U adjacent to it.

[0036] The stator lamination stack individual laminations 22 can each have at least one projection 23 extending outwards in the radial direction R for each rib region 30, 40. By arranging the stator lamination stack individual laminations 22 one after the other in the longitudinal direction L, their respective projections 23 can also be arranged one after the other in the longitudinal direction L to form the respective rib region 30, 40.

[0037] The fin area 30 has a main fin area extent 32, which is oriented in the longitudinal direction L of the stator 10. Furthermore, the fin area 30 has an outer fin area surface 34, which, together with an inner housing surface 62 of the housing part 60 facing the stator lamination stack 20 in the radial direction R, defines a cooling medium flow gap 36 for cooling the stator 10 by means of the cooling medium 12. This cooling medium flow gap 36 is oriented in the radial direction R of the stator 10 and is designed for the flow of the cooling medium 12 in the circumferential direction U. In other words, the cooling medium flow gap 36 is arranged in the radial direction R between the stator lamination stack 20 and the housing part 60.The housing part 60 can preferably be designed as a hollow cylinder at least in certain areas, and particularly preferably at least over the entire inner surface 62 of the housing, which makes it possible to manufacture the housing part 60 with particularly little effort.

[0038] The second rib section 40 has a second main rib section extent 42, which is oriented in the longitudinal direction L of the stator 10. Furthermore, the second rib section 40 has a second outer surface 44, which, together with the inner housing surface 62 of the housing part 60 facing the stator lamination stack 20 in the radial direction R, defines a second cooling medium flow gap 46 oriented in the radial direction R of the stator 10 and provided for the flow of the cooling medium 12 in the circumferential direction U.

[0039] In a method for cooling the stator 10, during operation of the electric motor 100, i.e., when driving the motor vehicle K by means of the electric motor 100, the cooling medium 12 can be guided in the circumferential direction U of the stator 10 through the cooling medium passages 36, 46. To supply the stator 10 with the cooling medium 12, a pump 88 of the motor vehicle K or of the electric motor 100, shown schematically in Fig. 4, can be used.

[0040] The inner surface 62 of the housing part 60 is designed as a hollow cylinder inner surface.

[0041] The cooling device 80 has a supply channel 82 which extends radially R through the housing part 60 and through which the cooling medium 12 can be supplied to the at least one cooling medium flow gap 36 in the circumferential direction U of the stator 10. Opposite the supply channel 82 in the radial direction R, a drain channel 92 of the cooling device 80 is arranged, through which the cooling medium 12 can be discharged from the stator 10.

[0042] The feed channel 82, like the discharge channel 92, is arranged in the longitudinal direction L in the region of a stator lamination stack center 24 of the stator lamination stack 20. The stator lamination stack center 24 is indicated by a dashed line in Fig. 4. The discharge channel 92 opens into a second indentation 94 of the cooling device 80, opposite the first indentation 84 in the radial direction R, which has a second indentation interior 96. The second indentation interior 96 can also extend in the longitudinal direction L of the stator 10 over the entire length of the stator lamination stack.

[0043] The cooling device 80 also comprises a recess 84 arranged on the housing part 60, into which the supply channel 82 opens and which has an interior recess 86 that can extend in the longitudinal direction L of the stator 10 over the entire length of the stator lamination stack and is provided for distributing the cooling medium 12 in the longitudinal direction L along the fin areas 30, 40. The at least one recess 84 can preferably extend over at least 50% of the length of the stator lamination stack 20, thereby enabling an advantageous distribution of the cooling medium 12 in the longitudinal direction L before it flows successively in the circumferential direction U through the respective cooling medium flow gaps 36, 46.The indentation 84 is particularly preferably able to extend over at least 80% of the stator lamination stack length of the stator lamination stack 20, thereby enabling a particularly advantageous distribution of the cooling medium 12 in the longitudinal direction L before it flows circumferentially U through the cooling medium flow gaps 36, 46. The flow through the respective cooling medium flow gaps 36, 46 in the circumferential direction U is illustrated by the arrows in Fig. 3.

[0044] Between the first rib section 30 and the second rib section 40, which is arranged adjacent to the first rib section 30 in the circumferential direction U, a groove section 50 of the stator lamination stack 20, also referred to as a cooling groove, extends in the longitudinal direction L. Since one of the groove sections 50 extends between each of the adjacent rib sections 30, 40, in the present variant 36 groove sections 50 are evenly distributed in the circumferential direction U.

[0045] The groove area 50 comprises an interior space 52, bounded in the radial direction R on one side by the stator lamination stack 20 and on the other side by the at least one housing part 60. This interior space has a greater radial extent than the respective cooling medium flow gap 36, 46. The groove depth h_N of the interior space 52 of the groove area 50, measured in the radial direction R, preferably has a depth of 2–3 mm, thereby ensuring good distribution of the cooling medium 12 within the interior space 52. The groove area 50 compensates for eccentric positional or misalignment tolerances that may arise during the joining of the stator lamination stack 20 to the housing part 60, resulting in very low pressure losses when the cooling medium 12 is conveyed through the stator 10.

[0046] In general, it has been shown that a ratio h_S : h_N between a gap height h_S of the respective cooling medium flow gap 36, 46 measured in the radial direction R to the groove depth h_N of the respective groove area 50 also measured in the radial direction R is generally and advantageously in a range of values ​​between 1 : 4 inclusive and 1 : 7 inclusive, in order to achieve particularly uniform and effective cooling with low pressure losses when conveying the cooling medium 12.

[0047] Furthermore, with regard to good cooling and acceptable pressure losses, it has generally proven advantageous if the circumferential rib width b_R of the respective rib sections 40, 60 has a value between 2 mm and 6 mm, and / or if the circumferential groove width b_N of the respective groove sections 50 has a value between 5 mm and 7 mm. A ratio b_R : b_N in a range of 1:1 and 1:4 has proven particularly advantageous. The respective dimensions of the groove width b_N, the rib width b_R, the groove depth h_N, and the gap height h_S are shown by way of example in Fig. 2.

[0048] The cover element 90 of the stator, also referred to as a cover plate, is sealed against the end face 26 of the stator lamination stack 20, which is arranged in the longitudinal direction L of the stator 10, and is designed to prevent uncontrolled escape of the cooling medium 12 from the respective cooling medium flow gap 36, 46 in the longitudinal direction L. However, controlled escape of the cooling medium 12 in the longitudinal direction L may be desirable in order to supply and thereby cool the winding heads of the electric motor 10 (not shown). To effect the controlled escape of the cooling medium 12, the cover element 90 has a plurality of through-openings 91 through which a flow of the cooling medium 12 can be directed towards the respective winding head (not shown).The through-openings 91 can, for example, be designed as nozzle openings, thus enabling targeted injection of the winding heads. In summary, the stator 10 features a circumferential flow around the stator lamination stack 20 in the direction U. For this purpose, the cooling medium 12, which is preferably cooling oil, is guided in opposite directions (see the opposite directions of the arrows illustrating the cooling medium 12 in Fig. 3) via the supply channel 82 and the indentation interior 86, which can also be referred to as the distribution channel, such that the cooling medium 12 can flow along the entire circumference of the stator 10, then collect on the side opposite the supply channel 82 in the radial direction R in the second indentation interior 96 of the second indentation 94, and exit the stator 10 via the outlet channel 92.

[0049] The stator 10 has groove areas 50, also referred to as longitudinal grooves. The inner diameter of a receiving bore in the housing part 60 is larger than the outer diameter of the stator lamination stack 20, so that the respective cooling medium flow gaps 36, 46 remain in the area of ​​the rib areas 30, 40, also referred to as groove walls, through which the cooling medium 12 can flow in the circumferential direction U. This flow pattern of the cooling medium 12 results in alternating high flow velocity and thus turbulent flow of the cooling medium 12 through the narrow cooling medium flow gaps 36, 46, with high heat transfer between the cooling medium 12 and the stator lamination stack 20, and highly turbulent flow through the groove area interiors 52 located between the adjacent cooling medium flow gaps 36, 46. The groove areas 50, also referred to as longitudinal grooves, provide pressure and flow equalization in each of the groove areas 50.This allows tolerances in the cooling medium flow gaps 36, 46 to be compensated for and pressure losses to be reduced.

[0050] The two cover elements 90, opposite each other in the longitudinal direction L, form lateral seals for a space for the cooling medium 12 formed by the housing part 60 and the stator lamination stack 20 and can be fixed to the housing part 60 by a respective press fit. Reference numeral list

[0051] 10 Stator

[0052] 12 Cooling medium

[0053] 14 Stator tooth

[0054] 20 Stator lamination stack

[0055] 22 Stator lamination stack single laminations

[0056] 23 lead

[0057] 24 Stator lamination center

[0058] 26 Stator lamination stack end face

[0059] 30 rib area

[0060] 32 Rib area - Main extension

[0061] 34 Rib area - outer surface

[0062] 36 Cooling medium flow gap

[0063] 40 second rib area

[0064] 42 second rib area main extension

[0065] 44 second rib area outer surface

[0066] 46 second cooling medium flow gap

[0067] 50 groove area

[0068] 52 Groove area interior

[0069] 60 Housing part

[0070] 62 Housing interior surface

[0071] 80 Cooling device

[0072] 82 Feed channel

[0073] 84 indentation

[0074] 86 Indentation interior

[0075] 88 Pump

[0076] 90 Cover element

[0077] 91 Passage opening

[0078] 92 Drainage channel

[0079] 94 second indentation

[0080] 96 second indentation interior

[0081] 100 Electric machine b_N Groove width b_R Rib width h_N Groove depth h_S Gap height K Motor vehicle

[0082] L Longitudinal direction

[0083] R Radial extension direction

[0084] II. Circumferential direction

Claims

Claims 1. Stator (10) for an electric motor (100) for driving a motor vehicle (K), comprising a stator lamination stack (20) which has a plurality of stator lamination stack individual laminations (22), with at least one housing part (60) which surrounds the stator lamination stack (20) at least partially in the circumferential direction (U) of the stator (10) and with a cooling device (80) by means of which a cooling medium (12) can be supplied to the stator (10) for at least partial cooling of the stator lamination stack, characterized in that the stator lamination stack (20) comprises at least one rib section (30) whose main rib section extent (32) is oriented in the longitudinal extent direction (L) of the stator (10) and which has a rib section outer surface (34),the at least one cooling medium flow gap (36) oriented in the radial direction (R) of the stator (10) and provided for flow with the cooling medium (12) in the circumferential direction (U) together with at least one housing inner surface (62) of the at least one housing part (60) facing the stator lamination stack (20) in the radial direction (R).

2. Stator (10) according to claim 1, characterized in that the at least one housing inner surface (62) of the at least one housing part (60) is designed at least partially as a hollow cylinder inner surface.

3. Stator (10) according to claim 1 or 2, characterized in that the cooling device (80) has at least one supply channel (82) which extends in the radial direction (R) through the at least one housing part (60) and through which the cooling medium (12) can be supplied to the at least one cooling medium flow gap (36) in the circumferential direction (U) of the stator (10).

4. Stator (10) according to claim 3, characterized in that the at least one feed channel (82) is arranged in the longitudinal extension direction (L) in the area of ​​a stator lamination stack center (24) of the stator lamination stack (20).

5. Stator (10) according to claim 3 or 4, characterized in that the cooling device (80) comprises at least one indentation (84) arranged on the housing part (60), into which the at least one supply channel (82) opens and which has an indentation interior (86) which extends at least substantially in the longitudinal direction (L) of the stator (10) and is provided for the distribution of the cooling medium (12) in the longitudinal direction (L) along the at least one rib area (30).

6. Stator (10) according to one of the preceding claims, characterized in that at least one second rib region (40) of the stator lamination stack (20) is provided, which is arranged in the circumferential direction (U) adjacent to the at least one rib region (30), and at least one slot region (50) of the stator lamination stack (20) extends in the longitudinal direction (L) between the at least one rib region (30) and the at least one second rib region (40).

7. Stator (10) according to claim 6, characterized in that the at least one slot area (50) comprises a slot area interior (52) which is limited in the radial extension direction (R) on one side by the stator lamination stack (20) and on the other side by the at least one housing part (60), and which has a larger radial extension than the at least one cooling medium flow gap (36).

8. Stator (10) according to claim 6 or 7, characterized in that at least one cover element (90) of the stator abuts at least one stator lamination stack end face (26) of the stator lamination stack (20) arranged in the longitudinal direction (L) of the stator (10), which is arranged to prevent uncontrolled escape of cooling medium (12) from the at least one cooling medium flow gap (36) in the longitudinal direction (L).

9. Electric motor (100) for a motor vehicle (K), with at least one stator (10) according to any one of claims 1 to 8.

10. Motor vehicle (K) with an electric motor (100) according to claim 9 and / or with a Stator (10) according to any one of claims 1 to 8.

11. Method for cooling a stator (10) according to one of claims 1 to 8 and / or an electric machine (100) according to claim 9, in which the cooling medium (12) is guided in the circumferential direction (U) of the stator (10) through the at least one cooling medium passage gap (36).

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