Stator housing, method for producing a stator housing, and electric motor for a motor vehicle having a stator housing

Abstract

The invention relates to a stator housing (1) for housing a stator winding (2) of a stator (3), the stator housing having a first housing part (4) and a second housing part (6) connected thereto along a joint (5), said housing parts defining a circumferential cavity (7) for receiving the stator winding (2) arranged in a fluid, such as oil, wherein the first housing part (4) and the second housing part (6) are fluid-tightly interconnected at the joint (5), wherein, on the radially (8) inner side (9) of the first housing part (4), there is an oil discharge groove (11) extending substantially in an axial direction (10) for the purpose of discharging oil from an air gap (12) between the stator (3) and a rotor (13) which interacts therewith during operation, wherein the first housing part (4) has a tab (14) which projects into the oil discharge groove (11) and which can be torn off. The invention also relates to a method for producing a stator housing (1) according to the invention, wherein the two housing parts (4, 6) are adhesively bonded to one another at the joint (5), and the tab (14) is subsequently torn off in order to allow oil in the air gap (12) to access the oil discharge groove (11). Furthermore, the invention relates to an electric motor (19) for a motor vehicle (20), said electric motor having a stator housing (1) according to any of the preceding claims and having a rotor (13) which is operatively related to the stator (3).

Description

[0001] P240659

[0002] - 1 -

[0003] Stator housing, method for manufacturing a stator housing and electric motor for a motor vehicle with a stator housing

[0004] The invention relates to a stator housing for enclosing a stator winding of a stator, comprising a first housing part and a second housing part connected thereto along a parting line, which define a circumferential cavity for receiving the stator winding arranged in a fluid, such as oil, wherein the first housing part and the second housing part are fluid-tightly connected to each other at the parting line, wherein an oil drainage groove extending substantially in the axial direction is provided on the radial inside of the first housing part to drain oil from an air gap between the stator and a rotor interacting with it in operation.

[0005] In current technology, electric motors, meaning both the stator and the rotor, can be actively cooled with a fluid such as oil to dissipate the waste heat generated during vehicle operation and to cool the power components. Complete tightness of the parts or joints is usually not achieved, so a certain degree of leakage is permitted or even accepted.

[0006] The fluid circuit can be open or closed. In the closed configuration, the fluid flows through the stator and / or the rotor and is conveyed, for example, via a pipe. In the open configuration, the fluid flows through the stator and / or the rotor and sprays out of the components into a sump. This type of cooling is implemented, for example, in centrifugal cooling using a rotor and / or cooling channels in a stator with end-winding cooling.

[0007] Stator slot cooling is also known in the prior art as a form of stator cooling. In this embodiment, the stator has an oil housing and at least one oil inlet that projects approximately into the inner diameter of the stator. Regarding the sealing of the oil housing, one known technical solution is to create a separation joint between two parts of the P240659

[0008] - 2 -

[0009] The oil housing is sealed by a radially sealing O-ring that projects radially inwards. Alternatively, an adhesive bonding solution is known. This solution involves bonding the oil housing tightly to the stator overmolding. Furthermore, the so-called "V-groove," designed according to the tongue-and-groove principle, is known from the prior art as a technical solution for achieving a tight bond.

[0010] Closed or open liquid circulation systems or slot cooling systems with an oil chamber including an oil inlet are also known for stator cooling. The oil chamber can be sealed with an O-ring or glued to the stator. However, both slot cooling solutions result in poor oil drainage and thus drag losses.

[0011] In a wet-running electric motor, the oil that collects between the rotor and stator generates drag losses. This oil must be able to drain away. In the case of stator slot cooling with an oil enclosure, the inner flange of the enclosure impairs oil drainage. Depending on the design of the oil enclosure, this inner flange is formed by the O-ring groove and / or the V-groove into which the adhesive is applied. The inner flange creates a wall that the oil must overcome before it can flow further. Until the oil drains from the enclosure, drag losses occur.

[0012] Furthermore, there are prior art solutions that omit the V-groove on the inner side to avoid protruding into the stator's inner diameter. However, this solution makes it more difficult to achieve a tight bond because the adhesive cannot be forced. A technical solution using an O-ring instead of adhesive is even more critical than a V-groove with regard to oil drainage and thus drag losses, as it is radially deeper.

[0013] The present invention aims to achieve an improvement over the prior art. Known disadvantages are to be eliminated or at least reduced. In particular, the aim is to reduce drag losses and to improve or optimize oil drainage from the oil housing. P240659

[0014] - 3 -

[0015] According to the invention, this is achieved in a stator housing as presented above by the fact that the first housing part has a tear-off tab that projects into the oil drainage groove.

[0016] In other words, the invention relates to an optimized oil drainage system for an oil enclosure of a fluid-cooled electric motor by means of a detachable tab.

[0017] To reduce friction losses, a detachable tab is used, which is attached to the oil housing / oil enclosure and detached after the oil enclosure of the system housing according to the invention has been bonded. This prevents any protrusion on the inner diameter of the stator, allowing the oil to flow freely from the air gap, thus minimizing friction losses and drag losses / drag torques. This means that there is no longer any protrusion or obstruction in the oil drain channel on the inner diameter of the stator, allowing the oil to flow freely from the air gap between the stator and rotor.

[0018] According to the invention, a detachable tab is provided on the oil housing, which is glued to a support. The tab forms the inner side of the adhesive groove. Adhesive is applied to the groove, activated, displaced, and spreads within it. The inner flange of the adhesive groove forms a circumferential wall that would impair oil drainage and lead to drag torques. Therefore, the tab is torn off after assembly. In this way, the oil located between the stator and rotor can immediately flow out of the air gap through at least one local opening on the inner flange, which is released by tearing off the tab.

[0019] In principle, any stator can have an enclosure. Whether the enclosure serves to encapsulate the winding head and / or for electrical insulation is not decisive or even relevant. The presented inventive solution is therefore not limited to slot-cooled stators, but applies to all stator lamination stacks that have a lateral enclosure smaller than the stator's inner diameter, which thus projects radially inwards and impairs oil drainage. P240659

[0020] - 4 -

[0021] Advantageous embodiments are claimed in the dependent claims and are explained in more detail below.

[0022] In the context of the description of the embodiments, the directional specifications refer to the electric motor and the stator housing. Accordingly, the axial direction is oriented longitudinally along the electric motor and the stator housing it incorporates, i.e., in the direction of the drive shaft. The radial direction corresponds to the height / radius of the stator housing. The circumferential direction is defined accordingly in the third dimension.

[0023] It has proven advantageous if the tab is dimensioned in such a way that, when the two housing parts are glued together along the parting line, it protects the oil drainage groove from the ingress or clogging of adhesive.

[0024] This design of the tab protects the oil drain groove from the ingress of or clogging by adhesive. This means that no adhesive is present in the oil drain groove to restrict or prevent the oil flow. Consequently, resulting drag losses are at least advantageously reduced, thus improving the operating efficiency of the electric motor.

[0025] By bonding the two housing parts along the separation joint, a short-profile design in the axial direction is achieved, which is advantageous with regard to reducing installation space and achieving a compact design of the system housing.

[0026] Furthermore, it is advantageous if the first housing part is essentially made of plastic or consists of plastic.

[0027] Manufacturing the first housing component entirely or predominantly from plastic allows for significant weight savings, contributing to lightweight construction and energy conservation. Furthermore, it opens up advantageous design possibilities that can be implemented simply, cost-effectively, and in series production for at least the first housing component using plastic injection molding. P240659

[0028] - 5 -

[0029] Furthermore, it is advantageous if a shear point is present between a main body of the first housing part located away from the separation joint and the tab.

[0030] The predetermined breaking point between the main body of the first housing part (the part furthest from the separation joint) and the tab allows for easy separation of the connection between the main body and the tab. Applying slight, preferably tensile or shear, forces causes the connection to fail in the area of ​​the predetermined breaking point. Consequently, the tab can be easily removed.

[0031] The predetermined breaking point is further preferably implemented structurally by thinning or tapering in the geometry of the tab or by indentations. This design of the tab advantageously allows for simple manufacturing via injection molding, preferably without a slide, resulting in a significant reduction in manufacturing costs.

[0032] It has proven advantageous if the tab is aligned in the radial direction.

[0033] As a result of the preferably precise or essentially radial alignment of the tab, easy access to the tab is achieved. This easy access allows assembly personnel to easily grasp the tab. Applying tensile or shear forces to the tab and the predetermined breaking points is also simplified by this design.

[0034] Furthermore, it is advantageous if the first housing part forms a circumferential wall adjacent to the oil drainage groove, at least in sections.

[0035] The surrounding wall is due to the inner flange of the adhesive groove / separation joint and is therefore advantageous in terms of adhesive bonding. The oil drainage flow can be advantageously influenced by the surrounding wall formed by the first housing part in the circumferential direction and adjacent to the oil drain groove. (See P240659)

[0036] - 6 - In the embodiment of the surrounding wall / inner ring with an opening in the area of ​​the oil drain groove, the oil drainage flow is advantageously easy to achieve from a manufacturing perspective. This means that the oil flows through the opening of the inner ring into the oil drain groove. This means that the oil that collects between the rotor and the stator flows directly out of the air gap through this opening in the inner ring. The direct drainage of the oil is advantageous with regard to reducing drag losses.

[0037] Furthermore, it is advantageous if the wall is present on both sides of the oil drainage groove.

[0038] By designing the oil drainage groove with a wall on both sides and formed circumferentially by the first housing part, the direction of oil flow from both sides of the oil drainage groove is advantageously achieved.

[0039] Furthermore, it is advantageous if the oil drainage groove is located in the radially lower area of ​​the stator housing at a 6 o'clock position.

[0040] By designing at least one oil drain groove, and thus the oil drain in the radially lower area, the technical effect is achieved that the oil flows away on its own. In other words, by integrating the oil drain at preferably exactly 6 o'clock, a conveniently simple oil collection is achieved. Furthermore, from this position, it is advantageously easy for the oil to flow away on its own along the oil drain groove. In principle, it is conceivable that, in addition to the single oil drain groove located at the 6 o'clock position (radially lower), multiple oil drain grooves could be arranged around the circumference of the housing. This could be, for example, at 9, 0, 3 o'clock positions, or at intermediate positions such as 10, 11, 1, or 5 o'clock.

[0041] Due to the straight course of the oil drainage groove without kinks or other discontinuities in its path, resembling a straight, linear channel, the oil drainage of this embodiment of the cooling fluid continues to occur advantageously without a reduction in flow velocity and with minimal flow friction losses, and thus advantageously faster than with a discontinuous or kinked channel, i.e., the oil drainage groove. Further embodiments of P240659

[0042] - 7 -

[0043] For example, non-straight or sloping / angled courses are generally conceivable.

[0044] In the context of the cooling system according to the invention, it is also advantageous if the stator winding is arranged in the cavity and an adhesive at the joint ensures at least partial connection between the two housing parts.

[0045] Furthermore, the predetermined breaking point is preferably provided as a thinning and in the axial direction on both sides of the tab. Due to the embodiment of the predetermined breaking point as a preferably thinning of the tab's cross-section, the mechanical stability of the tab is reduced as a result of the preferably geometric change in the area of ​​the tab. As a consequence of the reduced mechanical stability, failure of the tab in the area of ​​the predetermined breaking point is advantageously easy to achieve. This advantage is also achieved by designing the tab with a predetermined breaking point on both sides of the tab, viewed in the axial direction, and can be brought about more quickly. The embodiment of the tab with a preferably closed geometry ensures that the tab is gripped with sufficient force to break off.

[0046] The adhesive bond, at least in the area of ​​the tab, is preferably designed such that the adhesive bond detaches from the tab when the tab is removed. This detachable connection between the tab and the adhesive bond makes it advantageously possible to detach or tear off the tab, thus preserving the tightness and integrity of the adhesive bond as well as the positioning of the two housing parts relative to each other.

[0047] Furthermore, the contact surfaces of the two adjacent housing parts of the stator housing are preferably designed in the area of ​​the parting line such that the adjacent housing parts preferably have a tongue-and-groove geometry. This means that the first and second housing parts, respectively, are preferably designed with an axial inner or outer projection, respectively, in the area of ​​a support ring, viewed in the radial direction, as shown in P240659.

[0048] - 8 - interlock and border in a radial direction on an outer projection or inner projection.

[0049] This means that the areas of the housing parts designed as inner and outer projections in the radial direction alternate. The first housing part preferably has an inner projection at its outermost point in the radial direction. The tab of the stator housing according to the invention is preferably arranged on the outermost inner projection of the first housing part. This embodiment of the stator housing achieves a positive-locking connection between the two housing parts that goes beyond a simple bond using adhesive. This means that the strength of the connection, particularly under shear forces, is advantageously increased with regard to mechanical stability under the operating stresses in the electric motor.

[0050] A method for manufacturing a stator housing according to the invention is also presented, wherein the two housing parts are glued together at the parting line and then the tab is torn off to allow access to the oil drainage groove for oil in the air gap.

[0051] The presented method advantageously makes it possible to join a stator housing together from two housing parts in a process-reliable and preferably error-free manner, using a material-bonded and preferably adhesive bond, without adhesive penetrating an oil drainage groove.

[0052] Due to the process reliability of the method, no extensive and expensive tests are necessary to ensure that no adhesive has penetrated the oil drain groove. Consequently, the efficient operation of an electric motor without drag losses caused by adhesive entering the oil drain groove is guaranteed.

[0053] Furthermore, an electric motor for a motor vehicle is presented, comprising a stator housing according to the invention and a rotor that is operatively related to the stator. P240659

[0054] - 9 -

[0055] By designing an electric motor with the stator housing according to the invention, operation without or with at least reduced drag losses is achieved. This embodiment of the electric motor advantageously results in an increase in both power and efficiency through the integration of the stator housing according to the invention.

[0056] The invention is explained in more detail below with the aid of a drawing. Two embodiments of a stator housing according to the invention are shown. The drawing shows:

[0057] Fig. 1 shows a perspective view of a section of a first embodiment of a stator housing according to the invention in a bonded state with a tab in a side cross-sectional view,

[0058] Fig. 2 shows a perspective view of a section of the stator housing according to the invention in the first embodiment according to Fig. 1 in a bonded state after tearing off the tab in a side cross-sectional view.

[0059] Fig. 3 shows a perspective detail view of a tab, the predetermined breaking points and a separation joint between two housing parts as a section of the stator housing according to the invention in the first embodiment according to Fig. 1 in a side cross-sectional view,

[0060] Fig. 4 shows a perspective detail view of the tab and the predetermined breaking points of the stator housing according to the invention in a second embodiment in a top view.

[0061] Fig. 5 shows a perspective detail of the tab and the predetermined breaking points of the stator housing according to the invention in the second embodiment according to Fig. 4 in a side view.

[0062] The drawings are schematic only and serve solely to illustrate the invention. The same elements are identified by the same reference numerals. The features of the individual embodiments may be mutually complementary or interchangeable. P240659

[0063] - 10 -

[0064] Fig. 1 shows a perspective view of a section of a first embodiment of a stator housing 1 according to the invention in a bonded state with a tab 14 in a side cross-sectional view.

[0065] The essential components of the stator housing 1 of an electric motor 20 for a motor vehicle 21 according to the invention are shown, comprising a stator housing 1, a stator winding 2 of a stator 3, a first housing part 4, a parting line 5 and a second housing part 6, a cavity 7, a radial inner surface 8 9 of the first housing part 4, an oil drainage groove 11 extending in the axial direction 10, an air gap 12 between the stator 3 and a rotor 13, a tab 14 which has a predetermined breaking point 16 to a main body 15 of the first housing part 4 located away from the parting line, a circumferential wall 18 formed in the circumferential direction 17 through the first housing part 4 adjacent to the oil drainage groove 11, and a support 19. The first housing part 4 and the second housing part 6 together form an oil enclosure 22. The cavity 7 and the stator winding 2 are arranged in the oil enclosure 22.

[0066] The stator housing 1 according to the invention is shown in a first embodiment in which the stator housing 1 is bonded along the parting line 5, which is arranged between the first housing part 4 and the second housing part 6 of the stator housing 1. The two housing parts 4, 6 form the cavity 7 and together the oil enclosure 22 of the stator housing 1 according to the invention. The oil enclosure 22 of the stator housing 1 is attached to the support ring 19. The attachment is designed such that the oil enclosure 22 is bonded to the support ring 19 and / or supported from the outside. The oil enclosure 22 has a detachable, preferably tearable, tab 14 in its inner area. That is, the tab 14 projects into the inner area of ​​the oil enclosure 22.

[0067] The inner area is defined as the area on the inside 9 of the stator housing 1. The oil housing 22 is designed as a plastic part. The tab 14 forms the inner side of the parting line 5, which is designed in the form of a V-groove. During joining, i.e., the material-bonded connection of the first Ge- P240659

[0068] - 11 - Between housing part 4 and the second housing part 6 along the separation joint 5, adhesive is preferably applied to the separation joint 5. The separation joint 5 is designed in the form of an adhesive groove.

[0069] By pressing the first housing part 4 and the second housing part 6 together, the adhesive is forced towards the cavity 7 during assembly. This distributes the adhesive within the joint 5. The compression of the adhesive ensures a tight seal at the joint 5. The tab 14 serves no function during the assembly / joining of the first housing part 4 and the second housing part 6 and the resulting formation of the cavity 7.

[0070] Due to the inner flange 18 of the adhesive groove / adhesive joint in the parting line 5 / adhesive groove, a wall forms as a consequence of the inner flange 18, which impairs oil drainage and leads to drag torques. This wall, resulting from the inner flange 18, appears as a raised section in the radial 8 direction. To improve oil drainage and reduce drag torques, the tab 14 is broken off after assembly. Breaking off the tab 14 advantageously allows the oil to flow immediately out of the air gap 12 between the stator 3 and rotor 13 through a local opening 23 (not shown) on the inner flange 18, as shown in Fig. 2.

[0071] Fig. 2 shows a perspective view of a section of the stator housing 1 according to the invention in the first embodiment according to Fig. 1 in a bonded state after tearing off the tab in a side cross-sectional view.

[0072] The bonded state of the stator housing 1 with the detached tab 14 represents the final state of the stator housing 1 according to the invention. The tab 14 was detached after the material-fit, preferably adhesive, joining of the first 4 and second 6 housing parts / the assembly of the system housing 1 including the oil containment 22 and after the adhesive had cured. The detached tab 14 allows the oil, which accumulates during operation of the electric motor 20 between the P240659

[0073] - 12 -

[0074] Rotor 13 and stator 3 collects, locally through the local opening 23 at the inner collar 18 resulting from the tearing off of the tab 14, from the air gap 12 immediately further.

[0075] An oil drain groove 11, in the form of a channel for oil drainage, is provided behind the tab 14 on the oil housing 22 of the system housing 1. The oil drain groove 11 is flush with the inner diameter of the stator 3. Due to the flush alignment of the oil drain groove 11 and the inner diameter of the stator 3, the oil has no inner flange 18 and consequently no raised area to overcome in order to flow away.

[0076] Preferably, the tab 14 is provided at the bottom in the radial direction 8 and integrated into the system housing 1 according to the invention. This means that, in the installed state, the tab 14 is positioned at the radially lowest point 8. This radially lowest point 8 corresponds to a 6 o'clock position of the tab 14 with respect to the system housing 1. In principle, it is conceivable, in accordance with the principles of the system housing 1 according to the invention, that several tabs 14 distributed around the circumference, i.e., in the circumferential direction 17, are provided for a plurality of oil drainage grooves 11. Due to centrifugal force and / or because of the rotor 13, these additional oil drainage grooves 11 can be advantageous.

[0077] Whether the tab 14 is separated before or after the adhesive has cured depends on the bonding process. The adhesive bond, i.e., the adhesive tendon, is preferably designed such that it detaches from the tab 14 when the tab 14 is separated. By detaching the adhesive tendon from the tab 14, the tightness of the adhesive bond and thus the sealing of the cavity 7, in this embodiment as the interior of the oil housing 22 of the stator housing 1, is advantageously ensured under the operating conditions of the electric motor 20.

[0078] Fig. 3 shows a perspective detail view of a tab 14, the predetermined breaking points 16, and a parting line 5 between two housing parts 4, 6 as a section of the stator housing 1 according to the invention in the first embodiment according to Fig. 1 in a side cross-sectional view. The tab 14 of the oil housing 22 of the stator housing 1 according to the invention is shown in detail. P240659

[0079] - 13 -

[0080] It is shown that predetermined breaking points 16 are provided at several locations around the tab 14 at the transition from the tab 14 to the oil housing 22 of the stator housing 1 according to the invention. The predetermined breaking points 16 advantageously make it possible to detach, i.e., tear off, the tabs 14 without damaging the system housing 1 and, in particular, the functional part of the remaining geometry of the system housing 1.

[0081] These predetermined breaking points 16 are locally very thin and are therefore easily damaged when pulled away. The areas where the tab 14 is very thin are preferably numerically predefined and mechanically designed to ensure the functionality of the seal. Consequently, the tab 14 fails in the area of ​​the predetermined breaking points 16. The illustrated embodiment of the tabs 14 has the advantage that the predetermined breaking points 16 can be injection-molded / formed without slides in the injection mold. This embodiment therefore represents a cost-effective solution.

[0082] The two housing parts 4, 6 of the stator housing 1 according to the invention are connected to each other radially via a tongue-and-groove geometry and have a parting line 5 in the connection area. The tongue-and-groove geometry corresponds to an embodiment of the oil support ring 19 with an inner projection 24 and an outer projection 25, wherein the tab 14 is configured as a radially 8 projecting section of the part of the oil support ring 19 having the inner projection. In the illustrated embodiment, the tab 14 extends circumferentially 17 over a predetermined length of the oil support ring 19 and has a predetermined dimension in the axial 10 direction.

[0083] Fig. 4 shows a perspective detail view of the detachable tab 14 and the predetermined breaking points 16 of the stator housing 1 according to the invention in a second embodiment in a top view. It is shown that the tab 14 is arranged on a support ring 19.

[0084] The predetermined breaking points 16 are arranged in the axial 10 direction, to the right and left in the transition area of ​​the tab 14 to the support ring 19. By applying P240659

[0085] - 14 - preferably under pulling or shear forces, the tab 14 fails at the predetermined breaking points 16, so that the tab 14 is detached. Adhesive, preferably applied, activated and cured beforehand in the separation joint 5, remains in the separation joint 5 even after the tab 14 has detached, so that the adhesive forms an adhesive tendon in the separation joint 5. The adhesive tendon seals the cavity 7 / the oil enclosure 22 of the stator housing 1 according to the invention.

[0086] Fig. 5 shows a perspective detail view of the tab and the predetermined breaking points 16 of the stator housing 1 according to the invention in the second embodiment according to Fig. 4 in a side view.

[0087] The tab, designed as a detachable tab 14, constitutes the central element of the stator housing according to the invention. A multitude of possible embodiments of the tab 14 are conceivable and feasible within the scope of the inventive solution. Figure 5 shows the second embodiment of the tab 14, as in Figure 4. A two-part solution is preferred for manufacturing the bonded and sealed oil enclosure 22 of the stator housing 1 according to the invention. This two-part solution provides that the tab 14 is initially attached to the oil enclosure 22 as an additional component and then removed again after the assembly / bonding of the housing parts 4 and 6.

[0088] Furthermore, it is conceivable that the predetermined breaking points 16 of the tab 14 of the stator housing 1 according to the invention are produced by recesses in the oil housing 22 of the stator housing 1 according to the invention. In contrast to the embodiment shown, in the embodiment of the predetermined breaking points 16 via recesses, it is advantageous to injection mold the recesses using a slide in the injection molding tool. In this embodiment, the inner collar 18 is preferably post-processed in a predetermined manner to create an opening 23 for the oil to drain. In the context of the system housing 1 according to the invention with recesses as an embodiment of the tabs 14, it is conceivable that the oil housing 22 is made of metal. If a metallic oil housing 22 with recesses as an embodiment of the predetermined breaking points 16 is implemented as an embodiment of the oil housing 22, manual post-processing is required to create the local opening 23. P240659

[0089] - 15 -

[0090] List of reference signs

[0091] 1 Stator housing

[0092] 2 Stator winding

[0093] 3 Stator

[0094] 4 first housing part

[0095] 5 Separation joint / adhesive groove

[0096] 6 second housing part

[0097] 7 Cavity / Interior of the oil enclosure

[0098] 8 radial / radial direction

[0099] 9 Inside

[0100] 10 axial / axial direction

[0101] 11 Oil drain

[0102] 12 air gap

[0103] 13 Rotor

[0104] 14 tab

[0105] 15 main body

[0106] 16 Breakaway point

[0107] 17 tangential / circumferential direction

[0108] 18 inner bond / wall as a result of the inner bond / around running wall

[0109] 19 Support ring

[0110] 20 electric motor

[0111] 21 Motor vehicle

[0112] 22 Oil containment

[0113] 23 local opening / opening

[0114] 24 internal projection

[0115] 25 outside lead

Claims

P240659 - 16 - Patent claims 1. Stator housing (1) for enclosing a stator winding (2) of a stator (3) comprising a first housing part (4) and a second housing part (6) connected thereto along a parting line (5), which define a circumferential cavity (7) for receiving the stator winding (2) arranged in a fluid, such as oil, wherein the first housing part (4) and the second housing part (6) are fluid-tightly connected to each other at the parting line (5), wherein an oil drainage groove (11) extending substantially in the axial direction (10) is provided on the radial (8) inner side (9) of the first housing part (4) to drain oil from an air gap (12) between the stator (3) and a rotor (13) interacting with it in operation, characterized in that the first housing part (4) has a detachable tab (14) which projects into the oil drainage groove (11).

2. Stator housing (1 ) according to claim 1 , characterized in that the tab (14) is dimensioned such that, when the two housing parts (4, 6) are bonded together along the parting line (5), it protects the oil drainage groove (11 ) from ingress or clogging by adhesive.

3. Stator housing (1 ) according to claims 1 and 2, characterized in that the first housing part (4) is substantially made of plastic or consists of plastic.

4. Stator housing (1 ) according to one of claims 1 to 3, characterized in that a shear point (16) is provided between a main body (15) of the first housing part (4) located far from the separation joint and the tab (14).

5. Stator housing (1 ) according to one of claims 1 to 4, characterized in that the tab (14) is aligned in the radial direction (8).

6. Stator housing (1 ) according to one of claims 1 to 5, characterized in that the first housing part (4) forms a wall (18) that circumferentially surrounds at least the portion of the housing in the circumferential direction (17) adjacent to the oil drain groove (11 ). P240659 - 17 - 7. Stator housing (1 ) according to claim 6, characterized in that the wall (18) is present on both sides of the oil discharge groove (11 ).

8. Stator housing (1 ) according to one of claims 1 to 7, characterized in that the oil drainage groove (11 ) is arranged in the radially (8) lower region of the stator housing at a 6 o'clock position.

9. Method for manufacturing a stator housing (1 ) according to any one of claims 1 to 8, wherein the two housing parts (4, 6) are bonded together at the parting line (5) and then the tab (14) is torn off to allow access to the oil drain groove (11 ) for oil in the air gap (12).

10. Electric motor (19) for a motor vehicle (20) with a stator housing (1 ) according to one of the preceding claims, with a rotor (13) which is in operative relationship with the stator (3).

Images