Electric machine with radially nested but sectionally linear channels

Abstract

The invention relates to an electric machine (2) with an oil distribution ring (3) which has an inlet channel (4) extending at least partially in the circumferential direction (16) for feeding a cooling fluid into cooling channels (17) of a stator (9), with at least one deflection channel (5) which connects two cooling channels (17) of the stator (9) spaced apart from each other in the circumferential direction (16), with a circumferentially extending collecting channel (6) for the cooling fluid, for fluidically connecting at least one cooling channel (17) with at least one outlet (7) for wetting a winding head (8) of the stator (9) with the cooling fluid, wherein the inlet channel (4), the deflection channel (5) and the collecting channel (6) are nested at least partially in the radial direction (14), i.e. arranged one behind the other in the radial direction.

Description

[0001] The invention relates to an electric machine with an oil distribution ring, which has an inlet channel extending at least partially in the circumferential direction for feeding a cooling fluid into cooling channels of a stator, with at least one deflection channel connecting two cooling channels of the stator spaced apart from each other in the circumferential direction, with a collecting channel extending in the circumferential direction for the cooling fluid, for fluidically connecting at least one cooling channel with at least one outlet for wetting a winding head of the stator with the cooling fluid.

[0002] Prior art describes cooling systems for electric machines consisting of two nozzle rings / oil distribution rings bonded together, i.e., glued. The oil distribution rings have openings for spraying the stator winding heads. The two oil distribution rings are connected via axial cooling channels in the stator back. Oil enters through a feed into the B-side of the stator back. From there, the oil spreads circumferentially and reaches the A-side of the stator back through an axial channel. Some of the channels are interconnected circumferentially, allowing the oil to flow back along the B-side. The oil is routed between the two sides several times before entering a collection channel, where the nozzles spray it onto the winding heads. The axial channels can be arranged in a meandering configuration.

[0003] The prior art reveals various cooling systems for electrical machines.

[0004] Document CN 112 615 445 B discloses a motor, a drive assembly, and equipment. The further disclosed method comprises the steps of forming a plurality of first oil channels between the inner surface of a housing and the outer surface of a stator core, and forming a second oil channel at the root of a coil slot of the stator core. In this way, the purpose of double-layer oil flow across the outer surface of the stator core and the root of the coil slot of the stator core is achieved, effective cooling of the stator core and the coil winding is ensured, and after cooling oil has been injected from the oil injection port, the flow direction of the cooling oil in some of the second oil channels is opposite to that in the remaining second oil channels, resulting in offset return flow and a more uniform axial temperature of the stator iron core and the coil winding.The heat dissipation requirement of the motor under operating conditions of low speed, high torque, and high rotational speed is ensured, and the problem of the motor's coil winding overheating under these conditions due to poor heat dissipation of the stator iron core and coil winding in existing motors is solved. It is worth noting that an oil channel is provided on the outer diameter / surface of the stator core.

[0005] Document CN 116 154 441 A is situated in the technical field of drive motor cooling and discloses a drive motor stator oil cooling structure and a corresponding oil cooling method. The structure comprises a shell, a stator core, a stator winding, and an oil injection ring, and the stator core, the stator winding, and the oil injection ring are arranged in the shell; the stator windings are positioned on two sides of the stator iron core; the shell is provided with an oil inlet hole, a first annular groove, and a first oil injection hole, and the oil inlet hole, the first annular groove, and the first oil injection hole are sequentially connected; the oil injection ring is provided with a second annular groove and a second oil injection hole, and the second annular groove and the second oil injection hole are interconnected.The stator core is provided with an axial through-hole, which communicates with the first and second annular grooves. According to the invention, deep cooling of the stator core and synchronous cooling of the stator core and stator winding can be achieved. The overall cooling capacity is high, the technological process is simple, production and application costs can be significantly reduced, and the cooling effect of the stator core and stator winding can be more uniform. The oil injection ring is provided on one side.

[0006] Document CN 113 364 166 A discloses a structure for oil cooling a motor stator. Two axial grooves are formed in the outer surface of a stator core, and a main oil channel is formed between the grooves and the inner wall of a motor housing. Oil guide supports are installed symmetrically at both ends of the stator core. Each oil guide support comprises an oil guide section and an oil spray section, which are axially connected. The oil guide section has an annular structure and is aligned with the main oil channel to form an S-shaped oil channel. The oil spray section has a section with an arc-shaped structure and is positioned above the end of a winding, and several oil spray holes are formed in the oil spray section. The top of the motor housing is provided with an oil inlet, and the bottom is provided with an oil outlet. According to the invention, the oil guide supports are specially designed.After the oil channel formed on the outer surface of the stator core is installed together with the housing in a suitable manner, a stable axial S-shaped oil channel is formed on the outer surface of the stator core, ensuring complete stator cooling. The oil guide supports are aligned with the housing and form a closed oil spray groove, allowing the end of the winding to be completely cooled and ensuring effective winding cooling. In summary, the axial grooves on the outer surface of the stator core are located in close proximity to the main oil channels.

[0007] According to the current state of the art, two oil distribution rings are provided, arranged on both sides of the stator. This means that an oil distribution ring is provided on both the A-side and the B-side of the stator housing. The two sides are fluidically connected by axial cooling channels in the stator back. The oil distribution rings are made of two parts and bonded together. The oil enters one oil distribution ring and is subsequently guided multiple times through the axial cooling channels until it reaches a collecting channel. The oil collected in the collecting channel is then sprayed to the winding heads.

[0008] Both the two oil distribution rings and the bonding process used to join them according to current best practices are costly. The oil distribution rings themselves are correspondingly expensive and complex to manufacture. This is especially true because the bonding process is difficult to automate. The difficulty of automation stems primarily from the fact that the adhesive must not enter the oil channels. If the adhesive were to enter the channels, it would act as a restrictor. Such a restrictive effect must be avoided because the oil supply to the distribution ring occurs at low pressure. Extensive and numerous tests are required to verify the functionality of the bonding process and the oil distribution ring, resulting in significant additional costs on top of the already high manufacturing costs. Furthermore, production times are increased.

[0009] The present invention aims to achieve an improvement over the prior art. Known disadvantages are to be eliminated or at least mitigated. In particular, the goal is to increase the efficiency of the cooling system and reduce manufacturing costs.

[0010] In a cooling system as described above, this is achieved according to the invention by nesting the inlet channel, the deflection channel, and the at least partially radially inward, i.e., arranging them one behind the other in the radial direction. One could also say that an oil distributor ring is provided which has an inlet for cooling fluid, preferably oil, and forms an associated deflection channel that opens into a collecting channel of the oil distributor ring, furthermore forming at least one outlet in fluid communication with the collecting channel, preferably in the form of a spray nozzle, for wetting a winding head of a stator with the cooling fluid.

[0011] In other words, the invention relates to a cooling system with a redesigned sealing concept. According to the invention, the previously two-part oil distribution ring is manufactured as a single piece, so that all three channels (inlet channel / inlet, diverting channel, and collecting channel for the nozzles used to spray the winding heads) are aligned. Furthermore, the cooling system features a molded seal that seals the oil distribution ring. The molded seal replaces the previously expensive two-component seal. The latter is known in the art as a 2K seal. Grooves are formed in an E-stack of the stator.

[0012] By incorporating a molded seal, it is advantageously possible, with regard to manufacturing costs, to reduce the axial length of the oil distributor ring when made of plastic. This results in more space within the outer diameter, allowing for the integration of a third channel, the inlet channel, on the outer diameter of the oil distributor ring. The inlet channel is integrated radially into the oil distributor ring, parallel to the deflection and collection channels. The three channels are axially aligned. The inlet channel is thus designed as an integrated inlet channel.

[0013] The one-piece, integrated design of the oil distributor ring allows for a significant reduction in the number of injection molds / molds required for production. Instead of two injection molds or one two-piece injection mold, only one, one-piece injection mold is needed.

[0014] The one-piece design of the oil distribution ring also makes it advantageously possible to save the gluing process, which was required according to the prior art to join the two parts of the two-piece oil distribution ring, but is difficult to automate.

[0015] By eliminating the gluing process in the automated production line for the injection-molded oil distributor ring, a further reduction in manufacturing costs is possible. The oil distributor ring is also designed for use in spray cooling of the winding ends / winding heads. Integrating the one-piece oil distributor ring into the cooling system according to the invention results in savings in manufacturing and production costs.

[0016] The solution according to the invention makes it possible to achieve a space-saving design in the axial direction by arranging the cooling system channels (inlet / supply, deflection, and collection / receiving) for the electric machine radially one above the other, rather than at least partially arranging them side by side in the axial direction. The reduction in the axial length of the cooling system results in potential savings in terms of the required installation space, leading to a more compact design of the cooling system.

[0017] Advantageous embodiments are claimed in the dependent claims and are explained in more detail below.

[0018] It is therefore advantageous if the inlet channel on the one hand and the collector channel on the other each have at least one bulge that extends at least to the radial height of the circumferentially running deflection channel. These bulges can also be described as sections, extensions, interfaces, or connections, at the location and by means of which a fluidic connection with the cooling channels is achieved. This ensures good functionality.

[0019] When a molded seal is used between the oil distributor ring and the part containing the cooling channels, such as a stator housing or the laminations of a stator stack, to prevent leakage, and in particular the molded seal is designed as a two-component component, significant cost and radial installation space savings can be achieved. In other words, a preferred embodiment is achieved by designing the molded seal as a one-piece, preferably single-material component.

[0020] It is also advantageous if at least one bulge of the inlet channel extends in a radial direction in the first direction and at least one bulge of the collecting channel extends in a second direction opposite to it.

[0021] It is also advantageous if the collecting channel has at least one outlet designed as a nozzle or a large number of outlets designed as nozzles for spraying the winding head.

[0022] Furthermore, it is advantageous if the oil distributor ring has several radially protruding mounting lugs to attach the oil distributor ring to a stator housing, in particular by screwing it on.

[0023] If the oil distributor ring is designed as a plastic injection molded component, high quantities can be produced efficiently.

[0024] It has proven advantageous if the cooling channels in the stator run essentially or exactly in the axial direction and / or if an oil distribution ring is present on both sides of the stator.

[0025] It is also advantageous if half of the total number of outlets from the oil distribution rings arranged on both sides of the stator are located on one end face of the stator and the other half on the other end face of the stator.

[0026] For operational purposes, it is of course advantageous if a rotor is functionally assigned to the stator.

[0027] In connection with the explanation of the embodiments, the directional specifications refer to the drive train of the wind turbine and its rotor for which the main bearing housing according to the invention is designed. Accordingly, the axial direction is defined as the longitudinal direction of the wind turbine's drive train, and thus of the rotor and the longitudinal direction of the main bearing housing. The radial direction of the rotor corresponds to the vertical direction of the main bearing housing. The circumferential direction is defined accordingly in the third dimension.

[0028] It has proven advantageous if the oil distribution ring rests against a stator housing with an intermediate molded seal and / or if the inlet, the deflection channel and the collecting channel are in a line.

[0029] By inserting a molded seal between the oil distributor ring and the stator housing, it is advantageously possible to seal the connecting surface of the oil distributor ring and the stator housing by axially contacting the molded seal on both sides.

[0030] By designing the oil distributor ring so that the inlet / inlet channel, the diverter channel, and the collection channel are aligned, manufacturing cost savings can be achieved. This means that by arranging the inlet channel, the diverter channel, and the collection channel radially and essentially parallel to each other axially, the axial width of the oil distributor ring can be reduced. As a result of this reduced axial width, manufacturing an oil distributor ring with only one injection mold is advantageous in terms of production costs.

[0031] Furthermore, it is advantageous if the molded seal is a component separate from the stator housing and the oil distribution ring.

[0032] By designing the molded seal as a separate component, advantages arise with regard to the maintenance of the cooling system according to the invention, since the molded seal is replaced separately from the stator housing and the oil distributor ring.

[0033] Furthermore, it is advantageous if the molded seal is designed and constructed in such a way as to prevent leakage from the connection area between the oil distributor ring and the stator housing to the outside.

[0034] The form seal effectively seals the transition area against unintended oil leakage. By preventing leakage, the efficiency of oil usage is increased. This results not only in cost savings from using only the intended amount of oil, but also in improved lubrication of the winding heads.

[0035] It has proven advantageous if at least two, three, four or more outlets of the collecting channel are designed as nozzles.

[0036] By designing the collecting channel as a nozzle channel with several outlets in the form of nozzles, and in particular spray nozzles, i.e., outlet openings, a defined and reproducible exit of oil from the collecting channel is achieved, preferably at an increased velocity. An increased velocity is defined as a velocity that exceeds the flow velocity of the oil present in the collecting channel.

[0037] The defined oil discharge includes a defined wetting of the winding head or multiple winding heads. As a result of this technical effect, efficient wetting of the winding heads with a quantity of oil, preferably predetermined by the size of the outlet opening, is achieved.

[0038] With regard to the number of nozzles, it is advantageous to design the oil distribution ring with at least two, three, four, or preferably more nozzles to achieve uniform wetting of the circumferentially arranged winding heads of the stator. To achieve the described technical advantage, the nozzles are also preferably distributed at uniform intervals around the circumference.

[0039] Furthermore, it is advantageous if the oil distributor ring has several radially protruding mounting lugs in order to screw the oil distributor ring onto the stator housing.

[0040] The positive and / or non-positive connection of the oil distributor ring to the stator housing via screws ensures a technically advantageous way to maintain its position during operation of the electric machine. Furthermore, fixing the position of the oil distributor ring relative to the stator housing via a screw connection achieves the technical benefit of ensuring that the screws are tightened reproducibly with a predetermined torque, thus applying a suitably predetermined contact pressure to the molded seal and, consequently, to the housing. Both the fixed relative position and the predetermined contact pressure are particularly advantageous with regard to the stator's surroundings and the risk of oil leakage.

[0041] For defined and reproducible screw positioning, and with regard to the achievable freedom in the embodiment of the internal structure of the oil distribution channel, it is advantageous to provide radially projecting mounting lugs designed as protrusions. This embodiment allows the channel structure and guidance of the oil distribution ring to be independent of the mounting structure, i.e., the mounting lugs. The shape of the internal structure of the oil distribution ring is thus independent of the mounting lugs.

[0042] Furthermore, with regard to the assembly and the mechanical stress on the mounting lugs during operation of the electric drive motor, it is advantageous to provide a plurality of mounting lugs. Preferably, the oil distribution ring is equipped with at least six, seven, or eight mounting lugs. This multiple mounting lug design ensures that the forces acting on the screw connection via the stator connection are evenly distributed, thus promoting the longevity of the screw connection. Moreover, the multiple mounting lugs—that is, the number of mounting options and points—ensure that the oil distribution ring remains securely fixed even if one or more of the screw connections loosen during operation.

[0043] The fastening lugs are preferably provided in areas where the stator or stator housing has receptacles for the screws, preferably in the form of threaded holes. This allows for a technically advantageous screw connection.

[0044] Furthermore, it is conceivable within the scope of the technical invention if additional fastening lugs are provided, via which the connection to other housings of the cooling system or the system housing of the electric machine is provided.

[0045] The oil distributor ring is preferably designed as a one-piece, single-material, and integrally formed component. This embodiment offers advantages in terms of manufacturing costs compared to the prior art design of the oil distributor ring as a two-piece component. The bonding process required by the prior art is eliminated. Manufacturing costs are thus advantageously reduced.

[0046] Furthermore, it is advantageous if the oil distributor ring is designed as a plastic injection molded component.

[0047] Manufacturing the oil distributor ring as a plastic injection-molded component offers two key advantages. Using injection molding for the production of the oil distributor ring allows for automated and rapid production of multiple components (oil distributor rings) in a single casting using multi-cavity molds.

[0048] Furthermore, the use of injection molding advantageously reduces the weight of the component, preferably from the perspective of the lightweight construction principle sought in the automotive sector, particularly also for saving fuel resources.

[0049] It is also advantageous if axially aligned cooling channels are present in the stator housing.

[0050] The design of the stator housing, featuring axially aligned cooling channels, ensures that the oil is guided axially from one side of the housing to the opposite side. This allows for efficient oil flow from one axial side of the stator to the other and vice versa.

[0051] The sides preferably represent the A-side and the B-side of the stator housing of the electric drive machine. By guiding the oil over the stator housing / back of the stator, heat dissipation from the surface of the stator housing to the oil flowing through the cooling channels is advantageously achieved through convective heat transfer.

[0052] The axially aligned cooling channels are preferably arranged in a meandering pattern. This design of the cooling channel layout results in an advantageous increase in heat dissipation from the stator back compared to other channel layouts.

[0053] Furthermore, it is advantageous if an oil distribution ring is present on both sides of the stator housing.

[0054] By implementing the cooling system according to the invention with an oil distribution ring provided on each of the axial sides of the stator housing, a uniform oil distribution to the winding heads arranged on both sides of the stator is achieved in a technically advantageous manner.

[0055] The invention also relates in principle to a motor vehicle drive system with an electric drive motor and a cooling system.

[0056] The presented cooling system can reduce the manufacturing costs of vehicle drive systems with an electric drive motor.

[0057] The invention is explained in more detail below with the aid of a drawing. A first embodiment of the cooling system according to the invention is shown.

[0058] They show: Fig. 1 a longitudinal sectional view of a section of a first embodiment with a one-piece oil distribution ring and a molded seal, Fig. 2 a perspective view of the electrical machine according to the invention in the first embodiment, but without an inserted rotor, Fig. 3 a section III of the embodiment according to Fig. 1, Fig. 4 a singular, perspective view of the one-piece oil distributor ring as it appears in the Fig. 1, Fig. 2, Fig. 3 to Fig. 4 is used in the embodiment shown, Fig. 5 the oil distribution ring of the Fig. 4 in a top view from the side of the stator, Fig. 6 a cross-sectional view through the oil distributor ring made of Fig. 4 along line VI-VI and Fig. 7 the oil distributor ring Fig. 4 and Fig. 5 in the direction of the stator, i.e., compared to Fig. 4 from the other side.

[0059] The drawings are purely schematic and serve only 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.

[0060] The Fig. Figure 1 shows a two-dimensional representation of a cooling system 1 of an electric machine 2 according to the invention in a first embodiment. The electric machine 2 has a stator 9 on which an oil distribution ring 3 is arranged at each end face. The two oil distribution rings 3 can be designed as identical parts or are designed as such. The electric machine 2 can also be referred to as a drive machine.

[0061] The oil distribution ring 3 has an inlet channel 4 for cooling fluid, preferably oil. The inlet channel 4 can also be referred to as the inlet. The oil distribution ring 3 has a deflection channel 5 connected to the inlet channel 4, which opens into a collecting channel 6 of the oil distribution ring 3.

[0062] The collecting channel 6, which can also be referred to as the nozzle channel, is in fluid communication with at least one outlet channel 7, which is preferably designed as a nozzle, more specifically as a spray nozzle or spray nozzle. The outlet channel 7 can also be referred to as the outlet and is configured to wet a winding head 8 of the stator 9 with cooling fluid. The winding head 9 can also be referred to as the winding head.

[0063] The stator 9 has a laminated core consisting of a multitude of laminated plates 11.

[0064] A molded seal 10 adjoins the oil distributor ring 3. This seal in turn adjoins a stator housing (not shown) of the stator 9 or, as shown, rests directly against one of the sheet metal plates 7, namely one of the two end-faced sheet metal plates 11. The molded seal 10 thus delineates a connection area 12 of the oil distributor ring 3 to the stator housing in the axial direction 15, towards the stator 9. It is used to prevent leakage.

[0065] Because the oil distributor ring 3 is now made in one piece and is also used in combination with the molded seal 10, the manufacturing costs can be advantageously reduced compared to the combination with two-component seals (2K seals).

[0066] The Fig. Figure 2 shows a perspective component view of the cooling system 1 according to the invention for the stator 9 with the winding heads 8 as part of the electric machine 2 in the first embodiment according to Fig. Figure 1 in a perspective view. The oil distribution ring 3 of the cooling system 1 has a plurality of outlets designed as nozzles, which are formed by the plastic material forming the collecting channel 6 and which are distributed around the circumference.

[0067] The axial direction is indicated by reference numeral 13, the radial direction by reference numeral 14, and the tangential direction by reference numeral 16.

[0068] Furthermore, the oil distributor ring 3 has radial extensions 13 projecting from the oil distributor ring 3. These extensions are designed as mounting lugs 15. The oil distributor ring 3 is designed such that at least one, but preferably a plurality, of mounting lugs 15 are arranged at a predetermined distance from each other in the circumferential direction 16. The mounting lugs 15 are designed to enable the oil distributor rings 3 to be fixed to the stator housing, for example, by means of screws.

[0069] The oil distributor ring 3 also has the molded seal 10, which seals the connection area 12 of the oil distributor ring 3 to the stator housing.

[0070] The Fig. Figure 3 shows section III from Fig. Figure 1 shows an enlarged view. Visible in the axial direction from left to right are the oil distribution ring 3, the molded seal 10, and the sheet metal plates 11. The cooling channels 16, extending in the axial direction 13, are located in the sheet metal plates 11.

[0071] The inlet channel 4, the deflection channel 5, and the collecting channel 6 are clearly visible as the three channels 4, 5, 6 of the oil distribution ring 3, which are arranged one after the other in the radial direction 14 in the order of their naming (from radially outer to radially inner). They are thus arranged radially nested within or interlocked with one another. As a result of this arrangement, the oil distribution ring 3 is shortened in the axial direction 13, i.e., narrower, compared to the prior art.

[0072] The three channels 4, 5, 6 have sections that are arranged parallel to each other and oriented axially 13. Nevertheless, the three channels 4, 5, and 6 run predominantly circumferentially 16.

[0073] The ends of channels 4, 5, 6 facing the stator 9 are flush with the molded seal 10. The molded seal 10 seals the connection area 12 between the oil distribution ring 3 and the nearest sheet metal plate 11 and is designed in the area of ​​channels 3, 4, 5 with openings that correspond in shape and position to the openings of channels 3, 4, 5.

[0074] The connection area 12 can be referred to as the connection surface. The inlet channel 4 is designed as a predominantly circumferential channel through which the cooling fluid, preferably in the form of oil, is supplied, preferably via a pump. The oil is collected in the inlet channel 4, wherein the oil distribution ring 3 is designed with several inlet channels 4 in the circumferential direction 16.

[0075] The inlet channels 4 are oriented towards the stator 9. The deflection channel 5 achieves the technical effect of diverting the oil within the stator 9 between the two sides of the stator 9, i.e., side A and side B. This forces a meandering flow of the cooling fluid through the cooling channels 17 of the stator 9.

[0076] The collecting channel 6, preferably designed as a nozzle channel, is further configured so that the oil from the stator 9 collects in the collecting channel 6. The oil distribution ring 3 also has, on the side facing away from the stator 9, the outlet designed as a nozzle, the outlet channel 7, through which the oil is applied, i.e., directed, onto the winding head 8. The design of the

[0077] The oil distribution ring 3 of the cooling system 1 is located by means of its channels 4, 5, 6 and the outlet 7 in the Fig. 4, Fig. 5 and Fig. 7 presented in more detail.

[0078] The oil flows into the cooling system 1 according to the invention at a point in the stator housing, preferably into the oil distribution ring 3 made of plastic, e.g., injection-molded material, which is oriented towards the B-side of the stator 9. The oil is guided from the inlet channels 4 through the stator 9 to the deflection channels 5 which are oriented towards the A-side of the stator 9. Preferably, eight inlet channels 4 are provided per oil distribution ring 3 according to a particular embodiment of the cooling system 1.

[0079] On the A-side of the stator 9, the oil is then directed back to the B-side of the stator 9 via deflection channels 5. The oil is preferably deflected three to four times between the two sides of the stator 9, i.e., guided back and forth. The number of deflections is numerically predetermined via a cooling simulation. Afterwards, the oil is directed on each of the two sides, i.e., on the A-side and on the B-side, into the collecting channels 6, which are designed as nozzle channels.

[0080] Starting from the collecting channels 6, the oil is directed / flowed via the nozzles, which form the outlet 7, onto the winding heads 8. The oil flow wets the winding heads 8 on both sides of the stator 9.

[0081] The Fig. Figure 4 shows a perspective component view of the one-piece oil distribution ring 3 of the cooling system 1 according to the invention. Fig. 1 in a three-dimensional cross-sectional view. On the outer circumference of the oil distributor ring 3, protrusions or extensions are provided on its radial outer surface 13, which are designed in the form of mounting lugs 15. The mounting lugs 14 have axially oriented, preferably circular openings designed to receive fasteners such as screws. The mounting lugs 15 are thus designed to provide screw points.

[0082] The fastening lugs 15 are designed to connect the oil distribution ring 3 and the stator 9 to each other in a form-fit and force-fit manner. However, according to the invention, fastening lugs 15 with a different purpose are also conceivable. For example, the fastening lugs 15 could be provided for fastening to and with a system housing of the electric drive motor 2.

[0083] In line with the inventive solution, it is conceivable that the fastening eyelets 15 are designed differently with regard to their dimensions and preferably their diameter, and are arranged at different distances from each other in the circumferential direction 16. Furthermore, non-circular embodiments of the fastening eyelets 15, such as elliptical or angular ones, are also conceivable in principle.

[0084] The oil distribution ring 3 has a plurality of channels 4, 5, 6 arranged circumferentially 16 and extending across the cross-sectional area of ​​the oil distribution ring 3 and along its axial depth. The inlet channels 4 are designed to direct the oil from the collecting channel 6 to the stator 9. A plurality of inlet channels 4 are provided in the oil distribution ring 3 circumferentially 16. The number of inlet channels 4 is preferably eight, although a different number of inlet channels 4 may also be provided.

[0085] The oil distribution ring 3 has, among other things, the collecting channels 6 to provide the end of the oil line for the stator 9. According to the embodiment, at least four collecting channels 6 are provided per stator side, i.e., for side A and side B. Embodiments with more or fewer than four collecting channels 6 are also conceivable within the meaning of the technical teaching. The oil is diverted between the two sides of the stator 9, i.e., side A and side B of the stator housing, via the deflection channel 5.

[0086] The oil distribution ring 3 is preferably designed in the form of a plastic ring and has outlets 7 oriented in the axial direction 15, which are designed in the form of nozzles and in particular injection nozzles.

[0087] The Fig. Figure 5 shows a two-dimensional component representation of the one-piece oil distributor ring 3 according to Fig. 4 of the cooling system 1 according to the invention in the first embodiment according to Fig. 1 in a cross-sectional view.

[0088] The Fig. Figure 6 indicates the geometry of an outlet 7 designed as a nozzle. Due to the modified geometry of the outlet 7 and the associated collecting channel 6 compared to the prior art, only one mold is required for manufacturing the oil distributor ring 3 by injection molding, thus achieving cost savings.

[0089] The inlet channel 4, the deflection channel 5, and the collecting channel 6 each have 16 circumferentially extending sections arranged at the same radial height or at the same radial distance from the center of rotation of a rotor interacting with the stator 9 during operation. The inlet channel 6 has at least one bulge 4.1 extending to this radial height. The collecting channel 6 also has at least one bulge 6.1 extending to the same radial height. While the bulge 4.1 extends from the outside inward to this radial position, where the circumferential channel 5 also runs, the bulge 6.1 extends from the inside outward to this radial position or radial height. This could be described differently, namely as the three channels 4, 5, 6 being aligned.on a circumferential line at least partially at the same radial distance from the center of the stator 9 and the rotor.

[0090] The Fig. Figure 7 shows a section of the oil distribution ring 3 according to Fig. 4 from the other side. Compared to the illustrations of the oil distribution ring 3 in the Fig. 4 and Fig. Figure 5 shows the external geometry of the outlets 7 in the form of nozzles or outlet openings. The nozzles or outlet openings are arranged on the outer side of the oil distribution ring 3 facing the winding heads 8 and are preferably spaced evenly around the circumference. Reference symbol list 1 Cooling system 2 electric machine / electric drive machine 3 Oil distribution ring 4 Inlet channel 4.1 Bulging of the inlet channel 5 Deflection channel 6 Collection channel / nozzle channel 6.1 Bulge of the collecting channel 7 Outlet / Outlet channel / Nozzle 8 Winding head / winding head 9 Stator 10 Molded seal 11 sheet metal plate 12 Connection area / connection surface 13 axial / axial direction 14 radial / radial direction 15 fastening eyelets 16 tangential / circumferential direction 17 Cooling channel QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] CN 112 615 445 B

[0004] CN 116 154 441 A

[0005] CN 113 364 166 A

[0006]

Claims

[1] Electric machine (2) with an oil distribution ring (3) having an inlet channel (4) extending at least partially in the circumferential direction (16) for feeding a cooling fluid into cooling channels (17) of a stator (9), with at least one deflection channel (5) connecting two cooling channels (17) of the stator (9) spaced apart from each other in the circumferential direction (16), with a circumferentially extending collecting channel (6) for the cooling fluid, for fluidically connecting at least one cooling channel (17) with at least one outlet (7) for wetting a winding head (8) of the stator (9) with the cooling fluid, characterized by , that the inlet channel (4), the deflection channel (5) and the collecting channel (6) are nested within each other at least section by section in the radial direction (14). [2] Electric machine (2) according to claim 1, characterized by, that the inlet channel (4) on the one hand and the collecting channel (6) on the other hand each have at least one bulge (4.1 or 6.1) which extends at least to the radial height of the circumferentially extending deflection channel (5). [3] Electric machine (2) according to claim 1 or 2, characterized by , that a molded seal (10) is used between the oil distribution ring (3) and the part of the stator (9) containing the cooling channels (17) to prevent leakage. [4] Electric machine (2) according to any one of claims 1 to 3, characterized by , that the at least one bulge (4.1) of the inlet channel (4) extends in a radial direction (14) and the at least one bulge (6.1) of the collecting channel (6) extends in a second direction opposite to it. [5] Electric machine (2) according to any one of claims 1 to 4, characterized by, that the collecting channel (6) has at least one outlet (7) designed as a nozzle or a plurality of outlets (7) designed as nozzles for spraying the winding head (8). [6] Electric machine (2) according to any one of claims 1 to 5, characterized by , that several radially projecting mounting lugs (15) are provided on the oil distributor ring (3) to attach the oil distributor ring (3) to a stator housing, in particular by screwing it on. [7] Electric machine (2) according to any one of claims 1 to 6, characterized by , that the oil distributor ring (3) is designed as a plastic injection molded component. [8] Electric machine (2) according to any one of claims 1 to 7, characterized by that the cooling channels (17) in the stator (9) run essentially or exactly in the axial direction (13) and / or that an oil distribution ring (3) is present on both sides of the stator (9). [9] Electric machine (2) according to claim 8, characterized by, that half of the total number of outlets (7) of the oil distribution rings (3) arranged on both sides of the stator (9) are arranged on one end face of the stator (9) and the other half on the other end face of the stator (9). [10] Electric machine (2) according to any one of the preceding claims, characterized by , that a rotor is functionally assigned to the stator (9).

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