Electrical machine for a motor vehicle

Abstract

The invention relates to an electrical machine (1) for a motor vehicle, comprising a temperature control device (2) designed to control the temperature of, in particular cool, at least one section of the electrical machine (1), wherein the electrical machine (1) has a laminated core (4) having a multiplicity of laminations arranged against one another in the axial direction of the electrical machine (1), wherein the temperature control device (2) has at least one temperature control channel (8), at least sections of which run through the laminated core (4) in the axial direction, wherein a supply ring (3) that delimits a supply chamber (5) is provided next to the laminated core (4) in the axial direction, said supply chamber (5) being connected to the temperature control channel (8) through which a temperature control medium is able to be conveyed, wherein the supply ring (3) has at least one outlet opening (12) through which temperature control medium is able to be output from the supply chamber (5) in the direction of at least one conductor element (11) that protrudes out of the laminated core (4) in the axial direction.

Description

[0001] Electric machine for a motor vehicle

[0002] The invention relates to an electric machine for a motor vehicle, comprising a temperature control device designed for temperature control, in particular for cooling, of at least one section of the electric machine, wherein the electric machine has a plate pack with a plurality of plates arranged next to one another in the axial direction of the electric machine, wherein the temperature control device has at least one temperature control channel running at least partially through the plate pack in the axial direction, wherein a feed ring delimiting a feed space is provided adjacent to the plate pack in the axial direction, which feed space is connected to the temperature control channel through which a temperature control medium can be conveyed.

[0003] Electrical machines of the type mentioned above, which have a temperature control device provided for temperature control, in particular for cooling, of the electrical machine, are generally known from the prior art. Typically, a temperature control channel is guided through the lamination pack of the stator in order to dissipate heat from the laminations. In order to supply the temperature control medium, which is guided in the temperature control channel, to the lamination pack, at least one supply ring is usually provided at an axial end of the lamination pack, i.e. on an end face of the stator, which supply ring delimits a supply chamber from which the temperature control medium is introduced into the temperature control channel. In other words, the supply chamber usually forms an annular chamber into which the temperature control medium is guided. In the supply chamber, the temperature control medium is pressurized with respect to the environment and is sealed off from the environment by the supply ring.

[0004] From the supply chamber, the temperature control medium enters the temperature control channel via one or more inlet openings, allowing the temperature control medium to flow through the stator or the laminated core and exit it, usually at the axial end faces. In this area, the temperature control medium is guided over the so-called "winding heads," i.e., the conductor elements emerging from the laminated core, to also temperature control these. After leaving the laminated core and flowing over the winding heads, the temperature control medium typically flows radially along the outside of the conductor elements and then collects in a base area of ​​the housing, which has a drain opening.This means that in an "upper area" viewed in the vertical direction, the temperature control of the conductor elements is reduced compared to the lateral areas or the lower areas of the conductor elements, since in the upper area the conductor elements can only be flowed over for a short time and then the temperature control medium runs laterally along the conductor elements and can transfer or absorb more heat there.

[0005] Particularly in the critical operating ranges of the electrical machine, heating may occur in an axial end region of those conductor elements of the winding heads located in such upper regions in the vertical direction, for example, at a 12 o'clock position, compared to the remaining conductor elements, particularly those arranged laterally or in a lower region, particularly at a 6 o'clock position. This may result in the conductor elements that are heated compared to the remaining conductor elements representing the limiting factor in the temperature control of the electrical machine, so that in a borderline case, a reduction in the performance of the electrical machine may be necessary due to an overtemperature in the described region.In other words, in such a case the electrical machine would be more powerful overall, although the power capacity of the electrical machine cannot be fully utilized due to a few individual conductor elements.

[0006] The invention is based on the object of providing an improved electrical machine for a motor vehicle, in which in particular the temperature control of the conductor elements is improved.

[0007] This object is achieved by an electric machine having the features of claim 1. Advantageous embodiments are the subject of the dependent claims. As initially described, the invention relates to an electric machine for a motor vehicle. The electric machine is specifically designed as a traction drive, so that torque for driving the motor vehicle can be provided by means of the electric machine. The electric machine can in particular be designed as an axle drive. The electric machine has a temperature control device that is provided for temperature control, specifically cooling, at least one section of the electric machine. The term "temperature control" is therefore understood to mean both cooling and heating.

[0008] The electric machine has a plate pack, which can specifically form the stator base body of the electric machine. The plate pack comprises a plurality of individual plates or "laminations" arranged next to one another in the axial direction of the electric machine. The temperature control device has at least one temperature control channel, which runs at least partially through the plate pack in the axial direction. If temperature control medium is guided through the temperature control channel, the temperature control medium can be in thermal exchange with the plate pack in order to temperature control the plate pack, in particular to absorb heat from the plate pack and dissipate it with the flow of the temperature control medium through the temperature control channel. In the axial direction, the electric machine has a feed ring adjacent to the plate pack, which delimits a feed chamber, in particular on the end face of the stator or the plate pack.The tempering agent can be conveyed into the feed chamber, whereby the feed chamber is connected to the tempering channel so that the tempering agent can flow from the feed chamber into the tempering channel.

[0009] The invention is based on the finding that the supply ring has at least one outlet opening through which the temperature control medium can be discharged from the supply chamber toward at least one conductor element protruding axially from the plate pack. In contrast to the previously described temperature control medium path, through which the temperature control medium flows from the supply chamber through an inlet opening into the temperature control channel and, following this, through the plate pack, and then exits the plate pack at an opening in the plate pack, an outlet opening is provided in the supply ring, which connects the supply chamber with the surroundings of the supply ring.

[0010] This makes it possible to discharge the temperature control medium from the supply chamber directly toward a conductor element, where the pressurized temperature control medium can exit the supply chamber through the outlet opening and flow directly to the conductor element, in particular without passing through the lamination stack. This enables targeted temperature control of the area of ​​the conductor element to which the outlet opening is assigned.

[0011] Advantageously, for example, it is possible to compensate for the fact that areas of the conductor elements are less strongly exposed to temperature control medium flow due to gravity, in particular conductor elements arranged vertically above the axis of rotation or above the axis of rotation, which are less strongly exposed to temperature control medium flow due to gravity, i.e. due to the flow direction of the temperature control medium, compared to conductor elements arranged to the side or below the axis of rotation. By specifically directing temperature control medium through the outlet opening into such areas, these areas can also be temperature-controlled in a defined manner, so that a uniform temperature control can be fundamentally ensured, thus preventing drops in performance of the electrical machine or reductions in the performance of the electrical machine due to excess temperatures in individual areas of conductor elements.

[0012] According to one embodiment of the electrical machine, it can be provided that the plate pack of the electrical machine has a first side and a second side, in particular a twist side, wherein the feed ring is arranged on the first side of the plate pack and / or a feed ring is arranged on the second side of the plate pack. The “twist side” is understood in particular to be the side on which the conductor elements, in particular so-called “hairpins”, are fanned out or on the side on which the conductor elements can be interconnected. The feed ring is arranged in particular on the axial side of the electrical machine or plate pack that is opposite the twist side. Alternatively, the electrical machine can have both a first feed ring on the first side and a second feed ring on the second side of the electrical machine or plate pack.

[0013] The electrical machine can be further developed in such a way that the at least one outlet opening, in particular as a nozzle, is designed to discharge temperature control medium as a directed stream from the feed chamber. As already described, in addition to the stream of temperature control medium that is guided through the temperature control channel over the winding heads, the outlet opening can be specifically used to additionally guide a stream of temperature control medium from the feed chamber directly to the conductor elements. For example, the outlet opening can be designed as a nozzle, so that a targeted stream or jet of temperature control medium is guided into a spatially delimited area of ​​the conductor elements, namely the area that would otherwise only be slightly flowed over by temperature control medium, in particular an area of ​​the conductor elements located above the axis of rotation, in particular perpendicular to the axis of rotation. The targeted stream or jetThe jet of tempering agent can thus be emitted from the feed chamber in such a way that the relevant area of ​​the conductor elements can be tempered in a defined manner.

[0014] Furthermore, in the electrical machine, it can be provided that the outlet opening is designed to discharge temperature control medium onto an edge region of the at least one conductor element of the electrical machine that is spaced apart from the lamination pack in the axial direction. The edge region is understood to be, in particular, that region of the conductor element that is furthest away from the lamination pack, in particular the edge of the uppermost conductor element in the vertical direction, which edge points away from the lamination pack. Due to gravity or geometry, the flow of temperature control medium flowing out of the temperature control channel that is guided through the lamination pack is weakest at the described edge of the conductor element, in particular above the axis of rotation, in particular perpendicular above the axis of rotation.By specifically guiding the temperature control medium through the outlet opening into this edge area, the temperature control is made more uniform, so that the performance of the electric machine can be better utilized. The at least one outlet opening can also be arranged in an outlet area of ​​the feed ring, in particular on a circular segment of the feed ring arranged in the vertical direction. If the electric machine is arranged in the motor vehicle with its axis of rotation parallel to the horizontal, the effect of gravity is that conductor elements arranged above the axis of rotation, in particular conductor elements arranged in a circular segment of the feed ring or assigned to them, which lie above the axis of rotation, are less strongly exposed to the flow of temperature control medium than those conductor elements arranged to the side of the axis of rotation or below the axis of rotation.The at least one outlet opening is therefore expediently arranged in an outlet region of the feed ring, which is assigned to the conductor elements arranged vertically above the rotation axis. The feed ring can, for example, be divided into various circular segments, wherein the outlet region in which the at least one outlet opening is arranged is to be arranged in particular in the circular segment that is oriented vertically, for example, encompassing the "12 o'clock position."

[0015] In a further development of the electrical machine, it can be provided that at least two outlet openings are arranged in the outlet region, in particular -30° to +30° around the vertical axis. If the plate pack or the feed ring of the electrical machine arranged on the plate pack is viewed in the axial direction, the outlet region lies in particular between the 11 o'clock position and the 13 o'clock position, in particular the outlet region encompasses the 12 o'clock position. For example, the outlet region extends -30° and +30° in the circumferential direction relative to the vertical direction, so that the conductor elements arranged vertically above the axis of rotation and the conductor elements arranged in the range from -30° to +30° can be covered by the at least one outlet opening or the at least two outlet openings.

[0016] According to a further embodiment, the temperature control channel of the electric machine can be delimited by the plate pack by at least two different inlet openings in different plates, which are arranged one behind the other in the axial direction, and / or the temperature control channel and / or an additional channel can be formed by at least one welding channel of the plate pack. In the first variant described, at least two different plates can be provided in the plate pack, for example a first type of plate and a second type of plate. The different plates differ in particular in the arrangement or shape of the inlet openings provided in the plates. The inlet openings can differ, on the one hand, in their position on the plate or in the plate and / or in the size of their diameter.The different fins can, for example, only partially overlap, creating a baffle effect because the effective cross section or flow cross section through the temperature control medium can be guided through the two overlapping inlet openings, reducing it compared to a single inlet opening. Furthermore, a weld channel of the fin pack, through which the individual fins are connected to form the fin pack, can be used as a temperature control channel. Advantageously, this eliminates the need to form a dedicated temperature control channel by introducing inlet openings into the fins; instead, openings provided for forming the weld channel or openings formed by forming the weld channel can be used as inlet openings. Appropriate combinations of temperature control channel and additional channel are possible.

[0017] Furthermore, an additional channel can be provided in the electrical machine, from which temperature control medium can be dispensed to conductor elements on the second side of the lamination pack opposite the supply ring, in particular the twist side. Such an additional channel can be provided in particular when no temperature control medium can be provided from the housing of the electrical machine, in particular when direct supply of temperature control medium through the temperature control channel through the lamination pack to the winding head on the twist side cannot be ensured. In such a case, a section of the temperature control channel that is usually led through the lamination pack to the twist side can be omitted. For example, the temperature control channel can then be led from the supply chamber only to the first side and dispense temperature control medium there.Alternatively, the temperature control channel and the additional channel can be routed in combination in the axial direction through the plate pack, particularly at different radial positions. Furthermore, any number of temperature control channels and / or additional channels, particularly a plurality of temperature control channels and / or additional channels distributed circumferentially, is possible.

[0018] In addition to the electric machine, the invention relates to a drive train comprising a previously described electric machine. Furthermore, the invention relates to a motor vehicle comprising a previously described electric machine and / or a previously described drive train. As described, the electric machine can be configured in the drive train and / or in the motor vehicle as an electric axle drive.

[0019] All advantages, details and features described with regard to the electric machine are fully transferable to the drive train and the motor vehicle.

[0020] The invention is described below using exemplary embodiments with reference to the figures. The figures are schematic representations and show:

[0021] Fig. 1 is a schematic diagram of a section of an electrical machine in sectional view;

[0022] Fig. 2 is a schematic diagram of a section of the electrical machine of Fig. 1 in a perspective sectional view;

[0023] Fig. 3 is a schematic diagram of a section of the electrical machine of Fig. 1, 2 in axial view;

[0024] Fig. 4 is a schematic diagram of a section of a feed ring of an electrical machine from Fig. 1 - 3 in sectional view;

[0025] Fig. 5 is a schematic diagram of a section of a feed ring from Fig. 4 in perspective view; Fig. 6 is a schematic diagram of a section of a feed ring from Fig. 4, 5 in perspective view; and

[0026] Fig. 7 is a schematic diagram of a section of a lamination pack of the electrical machine of Fig. 1 -3.

[0027] Fig. 1 shows an electric machine 1 for a motor vehicle. The electric machine 1 is designed, for example, as a traction drive, in particular as an axle drive, of the motor vehicle or of a drive train. The electric machine 1 has a temperature control device 2 which comprises a feed ring 3 which is arranged axially adjacent to a disk pack 4 of the electric machine 1 and delimits a feed chamber 5 on the disk pack 4 in the axial and radial directions. In particular, as not shown in more detail, the feed chamber 5 is delimited radially on the outside by a housing of the electric machine 1. As shown by an arrow 6, temperature control medium can be introduced under pressure into the feed chamber 5, for example from radially outside through the housing, for example by means of a pump device (not shown).

[0028] The plate pack 4 comprises a plurality of individual plates arranged next to one another in the axial direction, which are combined, for example welded together, to form the plate pack 4. The terms “axial direction”, “radial direction” and “circumferential direction” refer to an axis of rotation 7 shown in Fig. 1. The axial direction runs along or parallel to the axis of rotation 7. The radial direction runs radially in the direction of the axis of rotation 7 or away from it. The circumferential direction refers to a tangential direction or direction of rotation about the axis of rotation 7. If reference is made to a vertical direction within the application, this is in particular perpendicular to the axis of rotation 7 and points upwards in the illustration in Fig. 1, for example against the direction of the arrow 6. The vertical direction particularly counteracts the direction of gravity, which, for example, acts downwards in Fig. 1.

[0029] In order to conduct temperature control medium, for example water or oil, through the electrical machine 1 or to temperature control various sections of the electrical machine 1, the temperature control device 2 has a temperature control channel 8 which is fed from the feed chamber 5. The foremost lamination of the lamination pack 4 can have an inlet opening 9 which is connected to further inlet openings 10 of the remaining laminations of the lamination pack 4. In other words, temperature control medium can flow from the feed chamber 5 through the inlet openings 9 of the first lamination and be diverted at the adjacent lamination in the axial direction, namely radially inwards, where the temperature control medium flow splits in the axial direction, namely in Fig. 1 to a first side, ie to the left, and through the lamination pack and the temperature control channel 8 to the second side or the "twist side".As a result, on the one hand, the lamination pack 4 is tempered by guiding the tempering medium through the lamination pack 4 and, on the other hand, the tempering medium reaches the winding heads or the conductor elements 11, for example hairpins, which emerge from the lamination pack 4.

[0030] The temperature control medium exiting the temperature control channel 8 on both sides flows around the conductor elements 11, whereby the temperature control medium flows downwards due to gravity, i.e., in the direction of the rotation axis 7 or opposite to the vertical direction, over the conductor elements 11. The further a section of the conductor element 11 is spaced from the outlet of the temperature control channel 8 in the axial direction, the less the temperature control medium flows over it, which can result in an uneven distribution of the temperature control.

[0031] To compensate for this uneven distribution, the feed ring 3 has at least one outlet opening 12 that connects the feed chamber 5 to the environment. In particular, the outlet opening 12 is selected such that a jet or stream of temperature control medium is formed, which is discharged from the feed chamber 5 and strikes an edge region 13 of the conductor elements 11 that points away from the lamination pack 4. In particular, the outlet opening 12 can be assigned to an outlet region 14 or arranged in this or formed in this in the feed ring 3, which is oriented vertically with respect to the axis of rotation 7. As shown, for example, in Fig. 3, the outlet openings 12 can be arranged at a "12 o'clock position" with respect to an axial view or a circumferential direction of the electrical machine 1. As shown, a plurality of outlet openings 12 can be provided.The outlet openings 12 can, for example, be provided continuously around the feed ring 3 or a limited outlet area 14 can be arranged in the vertical direction, for example in an outlet area 14 from -30° to +30° around the vertical direction or the vertical axis.

[0032] Fig. 4 shows a perspective view of a section of the feed ring 3, wherein several outlet openings 12 can be provided, which are located at a corner region of the feed ring 3 that delimits the feed chamber 5. Pressurized temperature control medium can therefore leave the feed chamber 5 through the outlet openings 12. The outlet openings 12 can, for example, act as nozzles and thus emit a directed jet of temperature control medium.

[0033] Fig. 5, 6 each show a perspective view of a section of the feed ring 3. Purely by way of example, three outlet openings 12, 12', 12" are provided, which are arranged in an outlet region 14. For example, a central outlet opening 12 can be arranged at an angle of 0°, ie vertically above the rotation axis 7. A first and second outlet opening 12', 12" can, in contrast, be offset by a defined angle in the circumferential direction, for example in a range of 0 to + / -30 0 in particular the first outlet opening 12' at -30° and the second outlet opening 12" at +30° or vice versa.

[0034] Fig. 7 shows a perspective view of the plate pack 4 with the feed ring 3 hidden. The plate pack 4 clearly has a plurality of inlet openings 9 which are in connection or fluid communication with inlet openings 10 of the plates of the plate pack 4, which are arranged one behind the other in the axial direction, so that the described distribution of the temperature control medium in the temperature control channel 8 is possible. Accordingly, the last plates in the axial direction can also have openings which act as baffles through which the temperature control medium can be discharged. Furthermore, a further inlet opening 15 is shown, which is connected to an additional channel 16. Temperature control medium can therefore additionally flow from the feed chamber 5 through the inlet opening 15 into the additional channel 16, which is also shown in Figs. 1, 2.The additional channel 16 can be formed, for example, by openings in the lamellae of the lamella pack 4, such as the inlet opening 10 of the lamellae, or the additional channel 16 can be formed by a welding channel through which the individual lamellae of the lamella pack 4 are welded together.

[0035] As shown, for example, in Fig. 1, the additional channel 16 makes it possible to discharge tempering medium at an outer radial position, so that improved tempering of the conductor elements 11, in particular on the second side or the “twist side”, is possible.

[0036] The advantages, details and features described in the individual embodiments can be combined with one another as desired, are interchangeable and transferable to one another.

[0037] Reference symbol electric machine

[0038] Tempering device

[0039] Feed ring

[0040] Disc pack

[0041] Feed room

[0042] Arrow

[0043] axis of rotation

[0044] Tempering channel, 10 Inlet opening 1 Conductor element 2 Outlet opening 3 Edge area 4 Outlet area 5 Inlet opening 6 Additional channel

Claims

Patent claims 1. An electric machine (1) for a motor vehicle, comprising a temperature control device (2) designed for temperature control, in particular for cooling, of at least one section of the electric machine (1), wherein the electric machine (1) has a plate pack (4) with a plurality of plates arranged next to one another in the axial direction of the electric machine (1), wherein the temperature control device (2) has at least one temperature control channel (8) extending at least partially through the plate pack (4) in the axial direction, wherein a feed ring (3) delimiting a feed chamber (5) is provided adjacent to the plate pack (4) in the axial direction, which feed chamber (5) is connected to the temperature control channel (8) through which a temperature control medium can be conveyed, characterized in that the feed ring (3) has at least one outlet opening (12),through which tempering means can be discharged from the supply chamber (5) in the direction of at least one conductor element (11) projecting from the lamination pack (4) in the axial direction.

2. Electrical machine (1) according to claim 1, characterized in that the lamination pack (4) of the electrical machine (1) has a first side and a second side, in particular a twist side, wherein the feed ring (3) is arranged on the first side on the lamination pack (4) and / or a feed ring (3) is arranged on the second side on the lamination pack (4).

3. Electrical machine (1) according to claim 1 or 2, characterized in that the at least one outlet opening (12), in particular as a nozzle, is designed to discharge temperature control agent as a directed stream from the supply chamber (5).

4. Electrical machine (1) according to claim 3, characterized in that the outlet opening (12) is designed to discharge temperature control medium onto an edge region (13) of the at least one conductor element (11) of the electrical machine (1), said edge region being spaced apart from the plate pack (4) in the axial direction.

5. Electrical machine (1) according to one of the preceding claims, characterized in that the at least one outlet opening (12) is arranged in an outlet region (14) of the feed ring (3), in particular on a circular segment of the feed ring (3) arranged in the vertical direction.

6. Electrical machine (1) according to one of the preceding claims, characterized in that at least two outlet openings (12, 12', 12") are arranged in the outlet region (14), in particular -30° - +30° around the vertical axis.

7. Electrical machine (1) according to one of the preceding claims, characterized in that the temperature control channel (8) is delimited by the plate pack (4) of at least two different inlet openings (9, 10, 15) in different plates, which are arranged one behind the other in the axial direction and / or that the temperature control channel (8) and / or an additional channel (16) is formed by at least one welding channel of the plate pack (4).

8. Electrical machine (1) according to one of the preceding claims, characterized by an additional channel (16) from which the temperature control medium can be discharged onto conductor elements (11) on the second side, in particular the twist side, of the lamination pack (4) opposite the feed ring (3).

9. Drive train comprising an electric machine (1) according to one of the preceding claims.

10. Motor vehicle comprising an electric machine (1) according to one of claims 1 to 8 and / or a drive train according to the preceding claim.

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