Shaft for a rotor device of an electric machine and rotor device for an electric machine of a vehicle

Abstract

comprising a shaft (1) for a rotor device (30) of an electric machine (50): - an input (2) for receiving rotational energy from a rotational energy generating machine (40), - an output (3) for transferring rotational energy to an electric machine or to a transmission device, and - a receiving device (4) for detachable fastening and for mechanical processing of the shaft (1), where - the receiving device (4) has two clamping areas (5, 6) which are spaced apart from each other in the axial direction (A), - wherein the two clamping areas (5, 6) are formed within the shaft (1) and have the same inner diameter, - characterized in that the shaft (1) has a flange device (12) for connection with a rotor carrier (31) of a rotor device (30) of an electric machine (50), and - wherein the flange device (12) is designed for a material-bonded connection with a rotor carrier (31) of a rotor device (30) of an electric machine (50).

Description

[0001] The invention relates to a shaft, in particular a rotor shaft, for a rotor device of an electric machine as well as a rotor device for an electric machine of a hybrid or electric vehicle with a shaft.

[0002] Furthermore, the invention relates to an electric drive unit for a hybrid or electric vehicle with an electric machine comprising a rotor device.

[0003] State of the art - as in Fig. Figure 1 shows that a rotor device 30 for an electric machine of a hybrid or electric vehicle has a shaft 1 and a rotor carrier 31.

[0004] The shaft 1 has an input 2 for receiving rotational energy from a rotational energy generating machine 40 (only indicated by reference numerals) and an output 3 for forwarding rotational energy to the rotor carrier 31.

[0005] Furthermore, the shaft 1 has a receiving device 4 for detachable fastening and for mechanical processing of the shaft 1, wherein the receiving device 4 has a single clamping area 5 with a clamping surface 7.

[0006] This clamping range 5 is necessary for the mechanical machining of the outer surface O of the shaft 1 or the rotor device 30. The shaft 1 can be attached to a machining center, such as a lathe, at clamping range 5.

[0007] In this context, it is known that axially large rotor carriers tend to vibrate during machining, for example, when the clamping area 5, or its single clamping surface 7, used to clamp the rotor device 30 to a machine tool, is located axially away from the center of gravity S of the rotor device 30. For more optimal support of mechanical forces during machining, a reduction in the axial distance between the cylindrical clamping surface 7 and the center of gravity S is desirable. However, this is not possible due to the existing and necessary oil bores and coolant channels 10, 11.

[0008] For example, DE 10 2007 006 986 B3 and DE 10 2020 132 413 A1 are cited as examples of state of the art.

[0009] The vibrations that occur necessitate, for example, lower processing speeds and can lead to poor surface finishes or dimensional variations. Ultimately, this results in higher costs.

[0010] Therefore, the object of the present invention is to provide a shaft for a rotor device of an electric machine, a rotor device for an electric machine of a hybrid or electric vehicle, and an electric drive unit for a hybrid or electric vehicle, each of which can be manufactured cost-effectively and which solves the problem outlined above or prevents vibrations during mechanical processing of the shaft and / or the rotor device in the best possible way.

[0011] This problem is solved by the features of the independent patent claims. Further advantageous developments are the subject of the dependent claims.

[0012] A first aspect of the present invention comprises a shaft, for example a rotor shaft, for a rotor device of an electric machine.

[0013] The shaft has an input for receiving rotational energy from a rotational energy-generating machine. In other words, the input allows coupling with, for example, an internal combustion engine.

[0014] Furthermore, the shaft includes an output for transmitting rotational energy to an electric motor, which can be used, for example, to convert electrical energy into mechanical energy and vice versa. It is also possible for the output to be coupled to a gearbox instead of an electric motor.

[0015] Furthermore, the shaft features a mounting device for detachable fastening and machining. This allows the shaft to be detachably attached to a machine tool or machining center, such as a lathe, for example, to machine the outer surface of the shaft.

[0016] The receiving device can be designed similarly to a cylindrical recess. More precisely, the receiving device can be designed as a bore. The receiving device can also extend inside and / or along the shaft in the axial direction. This allows for the creation of an internal receptacle for the detachable fastening of the shaft to, for example, a lathe.

[0017] Furthermore, the receiving device can have an inlet opening on one end face of the shaft. This inlet opening can serve to introduce lubricant into the shaft, which can then be conveyed, for example, to a rolling bearing and / or a vibration damping device. The inlet opening can also serve as access to the interior of the shaft for the detachable mounting of a machine tool.

[0018] Furthermore, the clamping device has two clamping areas that are axially spaced apart. Using two spaced-apart clamping areas allows for better support of forces during the machining of the outer surface of the shaft and / or a rotor assembly with a shaft. This spacing allows, for example, moments generated during a turning operation or a machining process to be absorbed, transferred, or compensated more effectively. This, in turn, dampens vibrations. The same applies to a rotor assembly with a shaft and a rotor carrier. In other words, the design of two clamping areas allows for better absorption of mechanical forces that occur during machining in a machine tool. This is achieved, for example, by shortening the axial distance between a clamping surface and the center of gravity of the shaft.

[0019] The two clamping areas are formed within the shaft. This allows, for example, machining of the outside of the shaft.

[0020] Furthermore, the clamping ranges have the same inner diameter, which can, for example, lie within a specified tolerance of ± 0.05 mm or less. This simplifies manufacturing.

[0021] Each clamping area can also have a clamping surface. While the clamping area describes a spatial region, the clamping surface of the clamping area specifies the concrete contact partner, which, for example, comes into contact with the lathe. Thus, two clamping surfaces can also be spaced apart from each other in the axial direction.

[0022] Furthermore, each clamping area or clamping surface can be designed as the inner lateral surface of a hollow cylinder.

[0023] The clamping surfaces can each run in a circle and / or be designed similarly to an inner surface of a hollow cylinder and / or have the same inner diameter, which can be within a specified tolerance, for example, less than or equal to ± 0.05 mm.

[0024] Furthermore, the receiving device may have a cooling area for supplying lubricant to one or more attachments, such as a rolling bearing or a vibration damping device.

[0025] The cooling area can be located between the two clamping areas.

[0026] The cooling area, or a surface within the cooling area, can also have an inner diameter larger than the inner diameter of the clamping surfaces of the two clamping areas, so that the clamping surfaces in the clamping areas project radially inwards compared to a surface in the cooling area. Thus, the cooling area between the two clamping areas forms a depression into which lubricant can flow.

[0027] Furthermore, the cooling area can have at least one inlet to at least one coolant channel. This allows lubricant to flow into the inlet and thus into at least one coolant channel. The at least one inlet can be located in a common surface of the cooling area. This common surface can be shaped similarly to the inner surface of a hollow cylinder.

[0028] The two clamping areas together with the cooling area and / or with at least one coolant channel of the shaft can form a coolant supply, so that lubricant can be conveyed through the receiving device by means of at least one coolant channel.

[0029] The two clamping areas and the cooling area can be fluidly connected to each other, allowing lubricant to flow from the clamping areas to the cooling area.

[0030] Furthermore, the shaft can have at least one coolant channel.

[0031] In this case, at least one coolant channel can extend in a radial and / or axial direction.

[0032] At least one coolant channel can connect the receiving device, which is shaped similarly to a cylindrical recess, to the outside of the shaft, so that lubricant can be guided through the wall of the partially hollow cylindrical shaft in the area of ​​the receiving device to one or more attached components, such as a rolling bearing or a vibration damping device. This allows the attached components to be cooled and / or lubricated.

[0033] In this description, a lubricant can be understood as a substance that can lubricate and / or cool. Thus, a lubricant can reduce wear and / or dissipate heat.

[0034] Furthermore, the shaft has a flange device for connection to a rotor carrier of a rotor device of an electric machine.

[0035] The flange device is designed for a material-bonded connection with a rotor carrier of a rotor device of an electric machine.

[0036] The flange assembly can be arranged or designed on the outside of the shaft.

[0037] Furthermore, the flange assembly can be arranged axially between the two clamping areas or their clamping surfaces. This is advantageous for the machining of a rotor device with a rotor carrier and a shaft, as the machining forces can then be optimally absorbed and transmitted.

[0038] Furthermore, the flange assembly and a clamping area can overlap at least partially in the axial direction. Even with this design, the machining forces acting upon it can be optimally absorbed and transmitted mechanically.

[0039] The flange assembly can be designed similarly to an annular disc.

[0040] Furthermore, the wave may have an inclined or sloping surface section on its outer side.

[0041] The inclined surface section can form an angle with the axial direction that is identical to the angle between the axis of a coolant channel in a cooling area of ​​the receiving device and the radial direction. This allows a coolant channel that begins or ends at the inclined surface section to be easily produced using a drill, as the drill can be positioned perpendicularly on the inclined surface section.

[0042] Furthermore, the shaft can have a center of gravity that lies axially outside the cylindrical space formed by the two clamping areas and the shortest connection between them. In this configuration, two clamping areas are advantageous in order to optimally absorb the forces and moments occurring during machining and thus reduce vibrations.

[0043] A second aspect of the present invention comprises a rotor device for an electric machine of a hybrid or electric vehicle.

[0044] It is expressly pointed out that the features of the shaft, as mentioned under the first aspect, can be used individually or in combination in the rotor device.

[0045] In other words, the features relating to the shaft mentioned above under the first aspect of the invention can also be combined with further features under the second aspect of the invention.

[0046] A rotor device for an electric machine of a hybrid or electric vehicle includes a shaft according to the first aspect.

[0047] Furthermore, the rotor device comprises a rotor carrier attached to a flange assembly on the shaft and a vibration damping device connected to the rotor carrier. The vibration damping device can dampen and / or eliminate vibrations introduced by the rotor carrier.

[0048] The vibration damping device can consist of two spring damper units connected in series and / or a centrifugal pendulum. This allows for optimal damping of vibrations in the rotor assembly.

[0049] A third aspect of the present invention comprises an electric drive unit for a hybrid or electric vehicle.

[0050] It is expressly pointed out that the features of the rotor device, as mentioned under the second aspect, can be used individually or in combination in the electric drive unit for a hybrid or electric vehicle.

[0051] In other words, the features relating to the rotor device mentioned above under the second aspect of the invention can also be combined with further features under the third aspect of the invention.

[0052] An electric drive unit for a hybrid or electric vehicle comprises a first electric machine with a first rotor device according to the second aspect and with a first stator device.

[0053] A laminated core can be arranged on the first rotor device or on its mounting for a laminated core. This core, in conjunction with the first stator device, can be used to generate a reinforced magnetic field.

[0054] Furthermore, the electric drive unit can include a second electric machine with a second rotor device and a second stator device.

[0055] A laminated core can be arranged on the second rotor device. This, in conjunction with the second stator device, can generate a stronger magnetic field.

[0056] Each stator device can surround its associated rotor device.

[0057] The vibration damping device of the first rotor assembly can be connected to the second rotor assembly. This allows vibrations from both the first and second rotor assemblies to be dampened.

[0058] A coupling device can be arranged between the first and second rotor devices to interrupt or restore a power flow.

[0059] The second electric machine can have a coupling device, which can be designed as a multi-plate coupling.

[0060] Furthermore, the coupling device can have first and second plates, wherein the first plates can be connected to the first rotor device and / or wherein the second plates can be connected to the second rotor device in a force-transmitting manner.

[0061] Furthermore, the electric drive unit can have a housing and a rolling bearing arranged in the housing, with which the shaft of the first rotor device can be rotatably mounted in the housing.

[0062] The invention concept presented above is expressed again and in addition in other words below.

[0063] This idea concerns - in simplified terms - a rotor device of an electric machine, wherein a shaft of the rotor device can have two clamping areas or two clamping surfaces inside it.

[0064] The cylindrical areas or clamping areas, or their clamping surfaces, can have the same diameter. "Same diameter" here can mean "within the specified diameter tolerances," which are typically less than or equal to ± 0.05 mm.

[0065] Such a rotor device for an electric machine can find applications in various scenarios, but is particularly advantageous for rotor devices with a high axial profile. This can be achieved by incorporating an additional functional element, such as a vibration damping device, a damper, a vibration absorber, a coupling, and / or a torque limiter.

[0066] Additional elements, such as inlets of bores or coolant channels for oil supply, can be arranged axially between the two clamping areas.

[0067] The inner diameter of the clamping areas can be radially smaller than the area in between or than a coolant area, so that, for example, burrs on bores do not have a disruptive effect when clamping the shaft on a lathe.

[0068] The invention is explained in more detail below with reference to an exemplary embodiment and the accompanying drawings. These schematically show: Fig. 1 a sectional view of a rotor device from the prior art; Fig. 2 a sectional view of a rotor device for an electric machine of a hybrid or electric vehicle; Fig. 3 the shaft of the rotor device Fig. 2; and Fig. 4 A sectional view of an electric drive unit for a hybrid or electric vehicle.

[0069] In the following description, the same reference symbols are used for the same objects.

[0070] Concerning Fig. Reference is made to the explanations at the beginning of the description, so further explanations are omitted here.

[0071] Fig. Figure 2 shows a sectional view of a rotor device 30 for an electric machine 50 of a hybrid or electric vehicle.

[0072] A more detailed description shows Fig. 2 a rotor device 30 with a shaft 1, which will be described in more detail below, and with a rotor carrier 31, which is attached to a flange device 12 of the shaft 1. The rotor carrier has a receptacle 35 for a laminated core 52, with the aid of which a magnetic field can be generated.

[0073] Furthermore, it shows Fig. 2, that the rotor device 30 comprises a vibration damping device 32 which is connected to the rotor carrier 31 to dampen and / or eliminate vibrations introduced by the rotor carrier 31.

[0074] The vibration damping device 32 has two spring damper units 33, 34 connected in series.

[0075] Fig. Figure 3 shows the shaft 1 of the rotor device 30. Fig. 2 in detail.

[0076] This is a shaft 1, in particular a rotor shaft, for a rotor device 30 of an electric machine 50.

[0077] Shaft 1 has an input 2 for receiving rotational energy from a rotational energy-generating machine 40 (indicated only by reference numeral 40). In other words, input 2 allows coupling with, for example, an internal combustion engine 40.

[0078] Furthermore, shaft 1 has an output 3 for transmitting rotational energy to an electric machine (not shown), which can convert not only electrical energy into mechanical energy, but also vice versa. However, it is also possible that output 3 is coupled to a gearbox instead of an electric machine.

[0079] Furthermore, according to Fig. 2 and Fig. 3 the shaft 1 a receiving device 4 for detachable fastening and for mechanical processing of the shaft 1. Thus, the shaft 1 can be detachably fastened to a machine tool or machining center, such as a lathe, in order to, for example, machine the outside O of the shaft 1.

[0080] The receiving device 4 is designed similarly to a cylindrical recess or as a bore and extends within or along the shaft 1 in axial direction A. Thus, an internal receiving device for a detachable fastening of the shaft 1 to, for example, a lathe is realized.

[0081] Furthermore, the receiving device 4 has an inlet opening 13 on an end face of the shaft 1. The inlet opening 13 serves to introduce lubricant into the shaft 1, whereby the lubricant can be conveyed, for example, to a rolling bearing 102 and to the vibration damping device 32.

[0082] The clamping device 4 has two clamping areas 5, 6, which are spaced apart from each other in the axial direction A. Furthermore, the shaft 1 has a center of gravity S, which lies outside the cylindrical space formed by the two clamping areas 5, 6 and the shortest connection between them in the axial direction A. In such a case, where the clamping areas 5, 6 are spaced apart from the center of gravity S in the axial direction A, two clamping areas are advantageous in order to absorb the forces occurring during machining as effectively as possible and thus reduce vibrations. Due to the two spaced clamping areas 5, 6, vibrations can therefore be reduced during machining of the outer surface O of the shaft 1. This is because, with regard to the axial distance of the clamping areas 5, 6 from the center of gravity S of the shaft 1, machining forces, which, for example,Vibrations that arise during a turning process can be better compensated for because shaft 1 can be supported at the two clamping areas 5 and 6. A shorter distance between one clamping area and the center of gravity S also helps to reduce vibrations. By reducing vibrations during machining of the outer surface O of shaft 1, shaft 1 can be manufactured at higher speeds and with tighter tolerances. This increases production and reduces costs.

[0083] As in Fig. 3, but also as in Fig. As can be seen in Figure 2, the two clamping areas 5, 6 are formed within the shaft 1. This allows, for example, machining of the outer surface O of the shaft 1. Each clamping area 5, 6 has a clamping surface 7, 8.

[0084] While each clamping area 5, 6 describes a spatial area, the clamping surface 7, 8 of the clamping area 5, 6 specifies the concrete contact partner, which e.g. comes into contact with the lathe.

[0085] Each clamping area 5, 6 or each clamping surface 7, 8 is designed as an inner surface of a hollow cylinder, wherein the clamping surfaces 7, 8 each extend in a circle and are designed similarly to an inner surface of a hollow cylinder and have the same inner diameter X. The diameter can lie within a specified tolerance, which is, for example, less than or equal to ± 0.05 mm.

[0086] Furthermore, they show Fig. 2 and Fig. 3, that the receiving device 4 has a cooling area 9 for supplying lubricant to one or more attachments, such as a rolling bearing 102 or a vibration damping device 32.

[0087] The cooling area 9 is located between the two clamping areas 5 and 6 and has an inner diameter Y that is larger than the inner diameter X of the clamping surfaces 7 and 8 of the two clamping areas 5 and 6. Thus, the clamping surfaces 7 and 8 of the clamping areas 5 and 6 project radially inwards in the direction R compared to a surface in the cooling area 9. This creates a depression in the cooling area 9 between the two clamping areas 5 and 6 into which lubricant can flow.

[0088] Furthermore, the cooling area 9 has inlets to two exemplary coolant channels 10 and 11. The inlets are formed in a common surface of the cooling area 9. This common surface is shaped similarly to the inner surface of a hollow cylinder.

[0089] The two clamping areas 5, 6, together with the cooling area 9 and the coolant channels 10, 11, form a coolant supply, so that lubricant can be conveyed through the receiving device 4 via the coolant channels 10, 11. For this purpose, the two clamping areas 5, 6 and the cooling area 9 are fluidically connected to each other, so that lubricant can flow from the clamping areas 5, 6 to the cooling area 9.

[0090] As mentioned, after Fig. 2 and Fig. 3 the shaft 1 several coolant channels 10, 11, which extend in radial and axial direction R, A (coolant channel 10 shown as an example) or only in axial direction A (coolant channel 11 shown as an example).

[0091] The coolant channels 10, 11 connect the receiving device 4, which is shaped similarly to a cylindrical recess, to the outer surface O of the shaft 1, so that lubricant can be guided through the wall of the partially hollow cylindrical shaft 1 in the area of ​​the receiving device 4 to one or more attachments, such as a rolling bearing 102 or a vibration damping device 32. This allows the attachments to be cooled and lubricated.

[0092] Furthermore, it shows Fig. 3, that the shaft 1 has a flange device 12 for connection to the rotor carrier 31 of the rotor device 30. The flange device 12 is designed for a material-fit connection with the rotor carrier 31 (see Figure 3). Fig. 2).

[0093] The flange assembly 12 is arranged or formed on the outer surface O of the shaft 1 and in the axial direction A between the two clamping regions 5, 6 or their clamping surfaces 7, 8, wherein in the axial direction A the flange assembly 12 and a clamping region 5 overlap at least partially. The flange assembly 12 is designed similarly to an annular disk.

[0094] Furthermore, it is assumed that Fig. 3 shows that the wave 1 has an inclined or sloping surface section 14 on its outer side O.

[0095] The inclined surface section 14 forms an angle α with the axial direction A, which is identical to an angle β between an axis of a coolant channel 10 of the cooling area 9 and the radial direction R. This allows the coolant channel 10 to be easily produced using a drill, as the drill can thus be positioned perpendicularly on the inclined surface section 14.

[0096] Fig. Figure 4 shows a sectional view of an electric drive unit 100 for a hybrid or electric vehicle.

[0097] The electric drive unit 100 comprises a first electric machine 50 with a first rotor device 30, as described above. Fig. 2 described, and a first stator device 51. A laminated core 52 is arranged on the first rotor device 30 or on its receptacle 35 for a laminated core 52. With the help of this, in conjunction with the first stator device 51, an enhanced magnetic field can be generated.

[0098] The electric drive unit 100 can include a second electric machine (not shown) with a second rotor assembly (not shown) and a second stator assembly (not shown). A laminated core, for example, can be arranged on the second rotor assembly. This, in conjunction with the second stator assembly, can generate a stronger magnetic field.

[0099] The vibration damping device 32 of the first rotor device 30 can, for example, be connected to the second rotor device.

[0100] Furthermore, the electric drive unit 100 has a housing 101 and a rolling bearing 102 arranged in the housing 101, with which the shaft 1 of the first rotor device 30 is rotatably mounted in the housing 101.

[0101] The exemplary coolant channel 11 supplies the rolling bearing 102 with lubricant, whereas the exemplary coolant channel 10 supplies the vibration damping device 32 with lubricant. Reference symbol list 1 wave 2 Entrance 3 Exit 4. Receiving facility 5 clamping range 6 clamping range 7 clamping surface 8 clamping surface 9 Cooling area 10 Coolant channel 11 Coolant channel 12 Flange device 13 Entrance opening 14 Surface section 30 Rotor device 31 rotor carriers 32 Vibration damping device 33 spring damper units 34 spring damper units 35 Mounting points for sheet metal stacks 40 Rotary energy generating machine / internal combustion engine 50 electric machine 51 Stator device 52 sheet metal package 100 Electric drive unit 101 cases 102 rolling bearings X Inner diameter of the clamping ranges Y Inner diameter of the cooling area A axial direction R radial direction S focus Outside D axis of rotation

Claims

[1] Shaft (1) for a rotor device (30) of an electric machine (50) comprising: - an input (2) for receiving rotational energy from a rotational energy generating machine (40), - an output (3) for transferring rotational energy to an electric machine or to a transmission device, and - a receiving device (4) for detachable fastening and for mechanical processing of the shaft (1), where - the receiving device (4) has two clamping areas (5, 6) which are spaced apart from each other in the axial direction (A), - wherein the two clamping areas (5, 6) are formed within the shaft (1) and have the same inner diameter, - characterized by , that the shaft (1) has a flange device (12) for connection with a rotor carrier (31) of a rotor device (30) of an electric machine (50), and - wherein the flange device (12) is designed for a material-bonded connection with a rotor carrier (31) of a rotor device (30) of an electric machine (50). [2] Shaft according to claim 1, - wherein each clamping area (5, 6) has a clamping surface (7, 8), and - wherein each clamping surface (7, 8) is designed as an inner lateral surface of a hollow cylinder. [3] Shaft according to claim 1 or 2, - wherein the receiving device (4) has a cooling area (9) for supplying one or more attachments with lubricant, and - wherein the cooling area (9) is arranged between the two clamping areas (5, 6). [4] Shaft according to claim 3, - wherein the cooling area (9) or a surface of the cooling area (9) has an inner diameter (Y) which is larger than the inner diameter (X) of clamping surfaces (7, 8) of the two clamping areas (5, 6), such that clamping surfaces (7, 8) in the clamping areas (5, 6) project inwards in a radial direction (R) compared to a surface in the cooling area (9). [5] Wave according to one of the preceding claims, - wherein the shaft (1) has at least one coolant channel (10, 11), and - wherein at least one coolant channel (10, 11) extends in a radial and / or axial direction (R, A). [6] Wave according to one of the preceding claims, - wherein the wave (1) has an inclined surface section (14) on its outer side (O), and - wherein the inclined surface section (14) encloses an angle (α) with the axial direction (A) which is identical to an angle (β) between an axis of a coolant channel (10) of a cooling area (9) of the receiving device (4) and the radial direction (R). [7] Wave according to one of the preceding claims, - wherein the receiving device (4) is designed similarly to a cylindrical recess, and / or - wherein the receiving device (4) is designed as a bore. [8] comprising a rotor device (30) for an electric machine (50) of a hybrid or electric vehicle: - a wave (1) according to any of the preceding claims, - a rotor carrier (31) which is attached to a flange device (12) of the shaft (1), and - a vibration damping device (32) connected to the rotor carrier (31) to dampen and / or eliminate vibrations introduced by the rotor carrier (31). [9] comprising an electric drive unit (100) for a hybrid or electric vehicle: - a first electric machine (50) with a first rotor device (30) according to claim 8 and with a first stator device (51), - a second electric machine with a second rotor device and with a second stator device, - wherein the vibration damping device (32) of the first rotor device (30) is connected to the second rotor device, and - wherein a coupling device is arranged between the first (30) and second rotor device to interrupt or restore a power flow.

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