Drive assembly, and a vehicle having such a drive assembly

Abstract

The present invention relates to a drive assembly (10): including a first shaft (12) having a first meshing portion (14) and a second shaft (16) having a second meshing portion (18), the first shaft (12) and the second shaft (16) being rotatable about a rotation axis (20), the second shaft (16) being configured as a hollow shaft, the first meshing portion (14) of the first shaft (12) and the second meshing portion (18) of the second shaft (16) forming an insertion meshing portion (22) for transmitting torque, and including at least one lubricant passage (24) for guiding a lubricant into the second shaft (16). Furthermore, the present invention relates to a vehicle having at least one such drive assembly (10).

Description

[Technical Field]

[0001] In drive assemblies having a rotor shaft and a transmission shaft connected to rotate together by a bayonet mesh, wear and fretting corrosion occur over time at the bayonet mesh. To prevent this as much as possible, the bayonet mesh is lubricated. This can be done, for example, by grease lubrication sealed by an O-ring or by a lubricant flow supplied to the bayonet mesh. [Background technology]

[0002] DE 10 2019 219 218 A1 discloses a drive assembly of this kind, in which the lubrication of the bayonet engagement can be achieved by means of a targeted lubricant flow.

[0003] The disadvantage here is that for a precise lubricant flow, a lubricant pump must often be used to deliver the lubricant, which is often not possible without a lubricant pump. DISCLOSURE OF THE INVENTION

[0004] According to the invention, a drive assembly, in particular for a vehicle, is proposed, which comprises a first shaft having a first meshing portion, the first shaft being configured as a rotor shaft of an electric machine.

[0005] The drive assembly further includes a second shaft having a second meshing portion, the second shaft being configured as a transmission input shaft.

[0006] The second shaft may be part of the transmission that is disposed in the transmission interior space.

[0007] The first shaft and the second shaft are rotatable about a rotation axis. The second shaft is configured as a hollow shaft. The first meshing portion of the first shaft and the second meshing portion of the second shaft form a bayonet mesh (or mating mesh) for transmitting torque. In other words, the first shaft and the second shaft are coupled to each other, in particular by the bayonet mesh, so as to rotate together. The first shaft and the second shaft can overlap each other in the axial direction in the region of the bayonet mesh.

[0008] The drive assembly includes at least one lubricant passage for guiding a lubricant into the second shaft. The lubricant passage may be configured as a lubricant rib and / or a lubricant reservoir. The lubricant may be oil.

[0009] In this way, the lubricant can be guided by splash lubrication into the second shaft (hollow shaft) via the lubricant passages and carried through the second shaft to the plug-in engagement, thereby enabling passive, forced lubrication of the plug-in engagement without the need for a lubricant or oil pump, i.e., the drive assembly is particularly oil-pump-free.

[0010] In this way, splash lubrication allows the lubricant to be supplied precisely to the plug-in meshing, thereby lubricating it. Particles inside the plug-in meshing that may be generated due to wear (or abrasion) can be carried away precisely along with the lubricant. This provides a low-cost, robust, and mechanically simple solution for lubricating the plug-in meshing. In particular, no seals or other components that are prone to wear are required to lubricate the plug-in meshing.

[0011] In this case, "axial" or "axial direction" means a direction aligned along or parallel to the axis of rotation. In other words, the axis of rotation is oriented in the axial direction. Accordingly, "radial" or "radial direction" means a direction emanating from the axis of rotation and aligned perpendicular to the axis of rotation.

[0012] In one development example, the lubricant passage may be arranged in the region of the end of the second shaft facing away from the first shaft. The lubricant passage can open or penetrate into the end facing away from the first shaft. The lubricant passage can guide the lubricant into the second shaft in a simple manner.

[0013] In one development example, the second shaft can have a plug member to prevent leakage of the lubricant. The plug member may be shaped in a tapered form. The plug member may be arranged at the end of the second shaft facing away from the first shaft. The plug member can prevent leakage of the lubricant from the end of the second shaft facing away from the first shaft. The plug member can prevent an unintended reflux of the lubricant returning from the second shaft, for example, into the internal space of the transmission. In this way, the entire lubricant introduced into the second shaft can be utilized for lubricating the insertion engagement portion.

[0014] In one development example, the first shaft can have at least one lubricant groove on its outer surface for accurately guiding the lubricant, particularly oil, on the outer surface of the first shaft. The lubricant groove can have an axial (axially aligned) region and a radial (radially aligned) region. The shape of the lubricant groove may correspond to the contour of the outer surface of the first shaft. A plurality of lubricant grooves distributed at equal angles (equally spaced) over the circumference of the first shaft may be provided on the outer surface of the first shaft. Accordingly, the lubricant can be accurately guided through the outer surface of the first shaft.

[0015] As an alternative or addition, in one development example, the first shaft and the second shaft may be supported by a (common) bearing. The first shaft and the second shaft may be supported by a (common) bearing in the region of the plug engagement portion. The (common) bearing can include a bearing inner ring (and a bearing outer ring). The bearing inner ring can contact the first shaft and the second shaft. For this purpose, the bearing inner ring can optionally have an axial length that is greater than that of the bearing outer ring. The bearing inner ring can have at least one lubricant opening for accurately guiding a lubricant, in particular oil, through the bearing inner ring. The lubricant opening can be configured as a through hole (or oil hole). The lubricant opening can be oriented radially. A plurality of lubricant openings distributed at equal angles (equally spaced) over the circumference of the bearing inner ring may be provided in the bearing inner ring. Accordingly, the lubricant can be accurately guided through the bearing inner ring.

[0016] In one development example, a radial shaft seal ring may be arranged on the first shaft. The radial shaft seal ring may be arranged axially spaced from the (common) bearing. The radial shaft seal ring can seal an electromechanical machine (which can drive, for example, the first shaft or the rotor shaft) against the interior space of the transmission (or the lubricant arranged therein).

[0017] In one development example, the drive assembly can have a lubricant guide ring for accurately guiding a lubricant, in particular oil, to the (common) bearing and / or the radial shaft seal ring. The lubricant guide ring may be arranged between the (common) bearing and the radial shaft seal ring. The lubricant guide ring particularly surrounds the first shaft towards the radially outer side. The lubricant guide ring is preferably stationary relative to the first shaft (when the shaft rotates, the lubricant guide ring does not rotate with it). For this purpose, the lubricant guide ring may be inserted into the housing of the drive assembly so as to rotate integrally.

[0018] The lubricant guide ring can have a first region that is radially aligned with respect to the first shaft (or with respect to the axis of rotation), in particular adjacent to the first shaft. The lubricant guide ring can have a second region that is axially aligned with respect to the first shaft (or with respect to the axis of rotation), in particular spaced apart from the first shaft. The first region can be arranged between the second region and the first shaft. The first region can be adjacent to the second region. The amount of lubricant guided by the lubricant guide ring (for example, by selecting the shape and / or dimensions of the lubricant guide ring) can be adjusted as desired for a (common) bearing and / or a radial shaft seal ring.

[0019] In one development, the first meshing portion of the first shaft can be configured as an outer meshing portion, and the second meshing portion of the second shaft can be configured as an inner meshing portion. Accordingly, the first shaft particularly projects into the second shaft (hollow shaft) with its first meshing portion. In other words, the second meshing portion of the second shaft can be externally fitted onto the first meshing portion of the first shaft.

[0020] In one development, the first shaft can be configured as a hollow shaft, the first meshing portion of the first shaft can be configured as an inner meshing portion, and the second meshing portion of the second shaft can be configured as an outer meshing portion. Accordingly, the second shaft particularly projects into the first shaft (hollow shaft) with its second meshing portion. In other words, the first meshing portion of the first shaft can be externally fitted onto the second meshing portion of the second shaft.

[0021] The drive assembly can be configured, for example, as an E-axle or can form components of an E-axle.

[0022] According to the present invention, there is proposed a vehicle, in particular a motor vehicle, having at least one drive assembly based on each of the above embodiments. For the associated advantages that can be achieved thereby, reference is made to the relevant description of the drive assembly. For yet another embodiment of the vehicle, the measures described in connection with the drive assembly and / or the measures described below can be employed.

Brief Description of the Drawings

[0023] Next, embodiments of the present invention will be described with reference to the accompanying drawings. The drawings show the following: [Figure 1] A partial side view showing a drive assembly according to a first embodiment. [Figure 2] A partial perspective view showing a first shaft of the drive assembly of FIG. 1. [Figure 3] A partial side view showing a drive assembly according to a second embodiment.

Modes for Carrying Out the Invention

[0024] The drive assembly is generally designated by reference numeral 10 in FIG. 1. The drive assembly 10 includes a first shaft 12 having a first engagement portion 14. The first engagement portion 14 is configured as an outer engagement portion 44 in this example. The first shaft 12 is configured as the rotor shaft of the electromechanical machine 13 in this example.

[0025] The drive assembly 10 has a second shaft 16 having a second engagement portion 18. The second engagement portion 18 is configured as an inner engagement portion 46 in this example. The second shaft 16 is configured as the transmission input shaft of the transmission 17 disposed in the transmission internal space 15.

[0026] The first shaft 12 and the second shaft 16 are configured to be rotatable about the rotation axis 20. The first shaft 12 projects into the second shaft 16 configured as a hollow shaft. The meshing portions 14, 18 of both shafts 12, 16 form a plug-in meshing portion 22. The first shaft 12 and the second shaft 16 are connected or joined to rotate integrally with each other via the plug-in meshing portion 22 formed by the first meshing portion 14 and the second meshing portion 18.

[0027] The drive assembly 10 includes a lubricant passage 24. The lubricant passage 24 is arranged in the region of the end 26 of the second shaft 16 facing away from the first shaft 12 and partially projects into the second shaft 16. In this way, the lubricant is sent upward or splashed upward as viewed in FIG. 1 from the lubricant sump (splash lubrication) in the internal space 15 of the transmission device based on the rotation of the individual members of the transmission device 17. In this way, the lubricant reaches the lubricant passage 24 and is guided from there into the second shaft 16.

[0028] The drive assembly includes a plug member 28. The plug member 28 is arranged at the end 26 of the second shaft 16 facing away from the first shaft 12. The plug member 28 is configured in a tapered shape to prevent leakage of the lubricant from the second shaft 16.

[0029] The second shaft 16 is supported at the end 26 facing away from the first shaft 12 by another bearing 33.

[0030] The first shaft 12 and the second shaft 16 are supported by a common bearing 34 in the region of the plug-in meshing portion 22. The common bearing 34 has a bearing inner ring 36 and a bearing outer ring 37. Here, the bearing inner ring 36 is in contact with the first shaft 12 and the second shaft 16. In this example, the bearing inner ring 36 has an axial length larger than that of the bearing outer ring 37.

[0031] A radial shaft seal ring 40 is arranged on the first shaft 12. The radial shaft seal ring 40 seals the electromechanical machine 13 against the transmission 17 or the transmission internal space 15. A lubricant guide ring 42 is arranged between the radial shaft seal ring 40 and the (common) bearing 34. The lubricant guide ring 42 can adjust the amount of lubricant guided to the (common) bearing 34 and / or the radial shaft seal ring 40 as desired.

[0032] The lubricant is guided into the second shaft 16 by the lubricant passage 24. Based on the rotation of the first shaft 12 and the constant introduction (additional flow) of the lubricant by the lubricant passage 24, the lubricant is guided particularly rightward as seen in FIG. 1 along the inner wall 19 of the second shaft 16 in the direction of the insertion engagement portion 22. The lubricant flows through the insertion engagement portion 22 and is lubricated accordingly.

[0033] Furthermore, the lubricant flows along the outer surface 30 (see FIG. 2) of the first shaft 12 and then exits outward between the bearing inner ring 36 and the lubricant guide ring 42. At this time, the lubricant is distributed by the lubricant guide ring 42 to the (common) bearing 34 and / or the radial shaft seal ring 40. Subsequently, the lubricant enters the transmission internal space 15 through the (common) bearing 34 and particularly flows back into a lubricant sump (not shown) based on gravity. From there, the lubricant can be redistributed in the transmission internal space 15 and reach the lubricant passage 28. In this way, the lubricant circulation path is closed.

[0034] FIG. 2 shows a part of a perspective view of the first shaft 12 of the drive assembly 10 of FIG. 1. The first shaft 12 has, on its outer surface 30, in this example, three lubricant grooves 32 (only two of the three lubricant grooves 32 are shown). These are arranged at equal intervals along the circumference of the first shaft 12. In other words, the lubricant grooves 32 are equidistant from each other along the circumference of the first shaft 12.

[0035] The lubricant groove 32 has an axial region 39 and a radial region 41 respectively. The shape of the lubricant groove 32 corresponds to the respective contours of the outer surface 30 of the first shaft 12. The lubricant groove 32 enables the lubricant to be accurately guided along the outer surface 30 of the first shaft 12. The lubricant groove 32 is not visible in FIG. 1 because the cross-sectional view shown in FIG. 1 does not extend through the lubricant groove 32.

[0036] FIG. 3 shows a part of a cross-sectional view of the drive assembly 10 according to the second embodiment. The difference between the second embodiment and the first embodiment shown in FIGS. 1 and 2 is that the first shaft 12 does not have a lubricant groove 32 (configuration without a lubricant groove).

[0037] Instead, the bearing inner ring 36 has a plurality of lubricant openings 38. In this example, these are configured as holes in the bearing inner ring 36 that extend radially. The lubricant openings open to the radial inner surface of the bearing inner ring 36 between the first shaft 12 and the second shaft 16. Accordingly, the lubricant that exits between the first shaft 12 and the second shaft 16 can be directly led out radially outward through the lubricant openings. In this way, the lubricant reaches the (common) bearing 34 and the lubricant guide ring 42. The lubricant guide ring 42 distributes the lubricant between the (common) bearing 34 and the radial shaft seal ring 40. Then the lubricant enters the transmission internal space 15 (see FIG. 1) through the (common) bearing 34 and flows back into the lubricant sump, particularly based on gravity. Accordingly, the lubricant circulation path is closed.

[0038] It is similarly conceivable that the first embodiment and the second embodiment of the drive assembly 10 can be combined with each other, that is, it is also conceivable that the drive assembly 10 has a lubricant groove 32 and lubricant openings 38.

Claims

Claim 1 Particularly in a drive assembly (10) for a vehicle, a first shaft (12) having a first meshing portion (14), a second shaft (16) having a second meshing portion (18), wherein the first shaft (12) and the second shaft (16) are rotatable about a rotation axis (20), the second shaft (16) is configured as a hollow shaft, a plug meshing portion (22) for transmitting torque is formed between the first meshing portion (14) of the first shaft (12) and the second meshing portion (18) of the second shaft (16), and a drive assembly including at least one lubricant passage (24) for guiding a lubricant, particularly oil, into the second shaft (16). Claim 2 The drive assembly (10) according to claim 1, wherein the lubricant passage (24) is arranged in a region of an end portion (26) of the second shaft (16) facing away from the first shaft (12), and particularly opens or penetrates into the end portion (26) facing away from the first shaft (12). Claim 3 The drive assembly (10) according to claim 1 or 2, wherein the second shaft (16) has a plug member (28), preferably shaped in a tapered manner, at an end portion (26) facing away from the first shaft (12) in order to prevent leakage of the lubricant from the end portion (26) of the second shaft (16) facing away from the first shaft (12). Claim 4 The drive assembly (10) according to any one of the preceding claims, wherein the first shaft (12) has at least one lubricant groove (32) on its outer surface (30) for accurately guiding a lubricant, particularly oil, on the outer surface (30) of the first shaft (12). Claim 5 The drive assembly (10) according to any one of the preceding claims, wherein the first shaft (12) and the second shaft (16) are supported by a bearing (34) particularly in a region of the plug meshing portion (22), the bearing (34) includes a bearing inner ring (36), the bearing inner ring (36) contacts the first shaft (12) and the second shaft (16), and the bearing inner ring (36) has at least one lubricant opening (38) for accurately guiding a lubricant, particularly oil, through the bearing inner ring (36).

6. The drive assembly (10) according to any one of the preceding claims, characterized in that a radial shaft seal ring (40) is arranged on the first shaft (12).

7. The drive assembly (10) according to any one of the two preceding claims, characterized in that the drive assembly (10) has a lubricant guide ring (42) for accurately guiding a lubricant, in particular oil, to the bearing (34) and / or the radial shaft seal ring (40).

8. The drive assembly (10) according to any one of the preceding claims, characterized in that the first engagement portion (14) of the first shaft (12) is configured as an outer engagement portion (44), and the second engagement portion (18) of the second shaft (16) is configured as an inner engagement portion (46).

9. The drive assembly (10) according to any one of claims 1 to 7, characterized in that the first shaft (12) is a hollow shaft, the first engagement portion (14) of the first shaft (12) is an inner engagement portion, and the second engagement portion (18) of the second shaft (16) is an outer engagement portion.

10. A vehicle, in particular a motor vehicle, having at least one drive assembly (10) according to any one of the preceding claims.

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