DRIVE ARRANGEMENT AND VEHICLE WITH SUCH A DRIVE ARRANGEMENT

Abstract

The invention relates to a drive assembly (10) comprising: a first shaft (12) having a first toothing (14); a second shaft (16) having a second toothing (18), wherein the first shaft (12) and the second shaft (16) are rotatable about an axis of rotation (20), wherein the second shaft (16) is designed as a hollow shaft, wherein the first toothing (14) of the first shaft (12) and the second toothing (18) of the second shaft (16) form a spline coupling (22) for transmitting a torque; and at least one lubricant channel (24) for conveying lubricant into the second shaft (16). The invention also relates to a vehicle having at least one drive assembly (10) of this type.

Description

[0001] Description

[0002] title

[0003] Drive arrangement and vehicle with such a drive arrangement

[0004] State of the art

[0005] In drive arrangements with a rotor shaft and a gear shaft that are torsionally coupled by means of splines, wear and fretting corrosion develop over time on the splines (or keyways). To prevent this as much as possible, the splines are lubricated. This can be achieved by means of grease lubrication, which is sealed, for example, by O-rings, or by means of a lubricant flow supplied to the splines.

[0006] DE 102019219218 A1 discloses such a drive arrangement, wherein the lubrication of the spline can be carried out by means of a targeted lubricant flow.

[0007] The disadvantage is that a targeted lubricant flow often requires a lubricant pump to deliver the lubricant. Targeted lubricant flow without a lubricant pump is often not possible.

[0008] Disclosure of the invention

[0009] According to the invention, a drive arrangement, in particular for a vehicle, is proposed, comprising a first shaft with a first gearing. The first shaft can be designed as the rotor shaft of an electric machine.

[0010] The drive assembly also includes a second shaft with a second gearing. The second shaft can be designed as a transmission input shaft. The second shaft can be part of a transmission that is arranged in a transmission interior.

[0011] The first shaft and the second shaft are rotatable about a rotational axis. The second shaft is designed as a hollow shaft. The first gearing of the first shaft and the second gearing of the second shaft form a spline (or a keyway) for transmitting torque. In other words, the first shaft and the second shaft are rotationally coupled to one another, in particular by means of the spline. The first shaft and the second shaft can overlap each other axially in the area of ​​the spline.

[0012] The drive assembly includes at least one lubricant channel for conducting lubricant into the second shaft. The lubricant channel can be configured as a lubricant rib and / or a lubricant reservoir. The lubricant can be oil.

[0013] The lubricant can thus be directed into the second shaft (hollow shaft) via the lubricant channel by means of spline lubrication and transported through the second shaft to the spline. This allows for passive forced lubrication of the spline without the use of a lubricant pump or oil pump. The drive arrangement is therefore, in particular, an oil pump-free design.

[0014] Thus, the spline can be specifically supplied with lubricant and lubricated using a spline lubrication system. Particles that may be created within the spline due to wear (or abrasion) can be specifically removed with the lubricant. This provides a cost-effective, robust, and mechanically simple solution for lubricating the spline. In particular, no seals or other wear-prone elements are required to lubricate the spline.

[0015] In this context, "axial" or "axial direction" refers to a direction aligned along the axis of rotation or parallel to it. In other words, the axis of rotation is oriented in the axial direction. Similarly, "radial" or "radial direction" refers to a direction aligned perpendicular to the axis of rotation and emanating from the axis of rotation.

[0016] According to a further development, the lubricant channel can be arranged in the region of an end of the second shaft facing away from the first shaft. The lubricant channel can open into or protrude into the end facing away from the first shaft. The lubricant channel can be easily guided into the second shaft.

[0017] According to a further development, the second shaft can have a plug element to prevent lubricant from escaping. The plug element can be conically shaped. The plug element can be arranged at the end of the second shaft facing away from the first shaft. The plug element can prevent lubricant from escaping from the end of the second shaft facing away from the first shaft. The plug element can prevent unwanted backflow of lubricant from the second shaft, for example, back into the gearbox interior. Thus, all of the lubricant introduced into the second shaft is available to lubricate the spline.

[0018] According to a further development, the first shaft can have at least one lubricant groove on its outer side for the targeted guidance of lubricant, in particular oil, on the outer side of the first shaft. The lubricant groove can have an axial (axially aligned) section and a radial (radially aligned) section. The shape of the lubricant groove can depend on the contour of the outer side of the first shaft. Several lubricant grooves can be provided on the outer side of the first shaft, which are distributed at equal angles (equidistant) over the circumference of the first shaft. This allows the lubricant to be guided specifically over the outer side of the first shaft.

[0019] Alternatively or additionally, according to a further development, the first shaft and the second shaft can be supported by means of a (common) bearing. The first shaft and the second shaft can be supported in the region of the spline by means of the (common) bearing. The (common) bearing can comprise 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 a greater axial length than the bearing outer ring. The bearing inner ring can have at least one lubricant opening for the targeted conduction of lubricant, in particular oil, through the bearing inner ring. The lubricant opening can be designed as a through-opening (or oil bore). The lubricant opening can be radially oriented. Several lubricant openings can be provided on the bearing inner ring, which are distributed at equal angles (equidistantly) over the circumference of the bearing inner ring.This allows the lubricant to be directed specifically through the bearing inner ring.

[0020] According to a further development, a radial shaft seal can be arranged on the first shaft. The radial shaft seal can be arranged at an axial distance from the (common) bearing. By means of the radial shaft seal, for example, the electric machine (which in particular drives the first shaft or

[0021] rotor shaft) must be sealed from the gearbox interior (or from the lubricant located therein).

[0022] According to a further development, the drive assembly can have a lubricant guide ring for the targeted routing of lubricant, in particular oil, to the (common) bearing and / or the radial shaft seal. The lubricant guide ring can be arranged between the (common) bearing and the radial shaft seal. The lubricant guide ring surrounds the first shaft, in particular radially outward. The lubricant guide ring is preferably stationary relative to the first shaft (the lubricant guide ring does not rotate with the rotating shaft). For this purpose, the lubricant guide ring can be incorporated into the housing of the drive assembly in a rotationally fixed manner.

[0023] The lubricant ring can have a first section that is aligned radially to the first shaft (or to the axis of rotation), in particular adjacent to the first shaft. The lubricant ring can have a second section that is aligned axially to the first shaft (or to the axis of rotation), in particular spaced from the first shaft. The first section can be arranged between the second section and the first shaft. The first section can be adjacent to the second section. By means of the lubricant guide ring (e.g. by selecting the shape and / or dimensions of the lubricant guide ring), the amount of lubricant that is guided to the (common) bearing and / or the radial shaft seal can be adjusted as desired.

[0024] According to a further development, the first toothing of the first shaft can be configured as external toothing, and the second toothing of the second shaft can be configured as internal toothing. Thus, the first shaft, in particular with its first toothing, extends into the second shaft (hollow shaft). In other words, the second toothing of the second shaft can be fitted onto the first toothing of the first shaft.

[0025] According to a further development, the first shaft can be designed as a hollow shaft, the first gearing of the first shaft as internal gearing, and the second gearing of the second shaft as external gearing. Thus, the second shaft, in particular with its second gearing, protrudes into the first shaft (hollow shaft). In other words, the first gearing of the first shaft can be slipped onto the second gearing of the second shaft.

[0026] The drive arrangement can, for example, be designed as an electric axle or form part of an electric axle.

[0027] According to the invention, a vehicle, in particular a motor vehicle, is proposed with at least one drive arrangement according to the above. Regarding the advantages achievable thereby, reference is made to the relevant explanations regarding the drive arrangement. The measures described in connection with the drive arrangement and / or those explained below can be used to further configure the vehicle.

[0028] Embodiments of the invention are explained below with reference to the accompanying drawings. They show:

[0029] Figure 1 shows a detail of a sectional view of a drive arrangement according to a first embodiment;

[0030] Figure 2 shows a detail of a perspective view of a first shaft of the drive arrangement according to Figure 1; and Figure 3 shows a detail of a sectional view of the drive arrangement according to a second embodiment.

[0031] The drive assembly is designated overall by reference numeral 10 in Figure 1. The drive assembly 10 comprises a first shaft 12 with a first toothing 14. The first toothing 14 is embodied in this case as an external toothing 44. The first shaft 12 is embodied in this case as the rotor shaft of an electric machine 13.

[0032] The drive assembly 10 has a second shaft 16 with a second gearing 18. The second gearing 18 is designed here as an internal gearing 46. The second shaft 16 is designed here as a transmission input shaft of a transmission 17 arranged in a transmission interior 15.

[0033] The first shaft 12 and the second shaft 16 are designed to rotate about a rotation axis 20. The first shaft 12 extends into the second shaft 16, which is designed as a hollow shaft. The gear teeth 14, 18 of the two shafts 12, 16 form a spline 22. The first shaft 12 and the second shaft 16 are rotationally connected to one another via the spline 22, which is formed by the first gear teeth 14 and the second gear teeth 18.

[0034] The drive assembly 10 includes a lubricant channel 24. The lubricant channel 24 is arranged in the region of an end 26 of the second shaft 16 facing away from the first shaft 12 and partially extends into the second shaft 16. The lubricant can thus be conveyed or propelled upwards from a lubricant sump (splash lubrication) in the transmission interior 15 due to the rotation of the individual elements of the transmission 17 in Figure 1. The lubricant thus enters the lubricant channel 24 and is guided from there into the second shaft 16.

[0035] The drive assembly includes a plug element 28. The plug element 28 is arranged at the end 26 of the second shaft 16 facing away from the first shaft 12. The plug element 28 is conical and prevents lubricant from leaking from the second shaft 16. The second shaft 16 is supported at the end 26 facing away from the first shaft 12 by means of a (further) bearing 33.

[0036] The first shaft 12 and the second shaft 16 are supported in the area of ​​the spline 22 by means of a (common) bearing 34. The (common) bearing 34 has a bearing inner ring 36 and a bearing outer ring 37. The bearing inner ring 36 contacts the first shaft 12 and the second shaft 16. In the example, the bearing inner ring 36 has a greater axial length than the bearing outer ring 37.

[0037] A radial shaft seal 40 is arranged on the first shaft 12. The radial shaft seal 40 seals the electric machine 13 from the transmission 17 and the transmission interior 15. A lubricant guide ring 42 is arranged between the radial shaft seal 40 and the (common) bearing 34. The lubricant guide ring 42 can be used to adjust the amount of lubricant supplied to the (common) bearing 34 and / or to the radial shaft seal 40 as desired.

[0038] The lubricant is fed into the second shaft 16 via the lubricant channel 24. Due to the rotation of the first shaft 12 and the constant introduction (continued flow) of lubricant via the lubricant channel 24, the lubricant is fed, particularly along the inner wall 19 of the second shaft 16, to the right in Figure 1, toward the spline 22. The lubricant flows through the spline 22, thereby lubricating it.

[0039] The lubricant continues to flow along the outer side 30 (see Fig. 2) of the first shaft 12 until it exits between the bearing inner ring 36 and the lubricant guide ring 42. Here, the lubricant is distributed to the (common) bearing 34 and / or the radial shaft seal 40 by means of the lubricant guide ring 42. The lubricant then passes through the (common) bearing 34 into the gearbox interior 15 and flows, particularly due to gravity, back into the lubricant sump (not shown). From there, it can be distributed again in the gearbox interior 15 and enters the lubricant channel 28. The lubricant circuit is thus closed. Figure 2 shows a section of a perspective view of the first shaft 12 of the drive assembly 10 according to Figure 1. The first shaft 12 has three lubricant grooves 32 on its outer side 30 (only two of the three lubricant grooves 32 are shown).These are arranged equidistantly along the circumference of the first shaft 12. In other words, the lubricant grooves 32 are equally spaced from each other along the circumference of the first shaft 12.

[0040] The lubricant grooves 32 each have an axial section 39 and a radial section 41. The course of the lubricant grooves 32 corresponds to the respective contour of the outer side 30 of the first shaft 12. By means of the lubricant grooves 32, the lubricant can be guided in a targeted manner along the outer side 30 of the first shaft 12. The lubricant grooves 32 are not visible in Figure 1, since the section shown in Figure 1 does not run through the lubricant grooves 32.

[0041] Figure 3 shows a section of a sectional view of the drive assembly 10 according to a second exemplary embodiment. The second exemplary embodiment differs from the first exemplary embodiment shown in Figures 1 and 2 in that the first shaft 12 does not have lubricant grooves 32 (lubricant groove-free design).

[0042] Instead, the bearing inner ring 36 has a plurality of lubricant openings 38. These are formed here as radially extending bores in the bearing inner ring 36. The lubricant openings open on the radial inside of the bearing inner ring 36 between the first shaft 12 and the second shaft 16. This allows the lubricant escaping between the first shaft 12 and the second shaft 16 to be directly drained radially outward via the lubricant openings. The lubricant thus 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 40. The lubricant then passes through the (common) bearing 34 into the gearbox interior 15 (see Fig. 1) and flows back into the lubricant sump, particularly due to gravity. This closes the lubricant circuit.It is also conceivable that the first embodiment and the second embodiment of the drive arrangement 10 can be combined with each other, i.e. the drive arrangement 10 has the lubricant grooves 32 and the lubricant openings 38.

Claims

Claims 1. Drive arrangement (10), in particular for a vehicle, comprising: a first shaft (12) with a first toothing (14), a second shaft (16) with a second toothing (18), wherein the first shaft (12) and the second shaft (16) are rotatable about an axis of rotation (20), wherein the second shaft (16) is designed as a hollow shaft, wherein the first toothing (14) of the first shaft (12) and the second toothing (18) of the second shaft (16) form a spline (22) for transmitting a torque, and at least one lubricant channel (24) for conducting lubricant, in particular oil, into the second shaft (16).

2. Drive arrangement (10) according to claim 1, characterized in that the lubricant channel (24) is arranged in the region of an end (26) of the second shaft (16) facing away from the first shaft (12) and in particular opens into or projects into the end (26) facing away from the first shaft (12).

3. Drive arrangement (10) according to claim 1 or 2, characterized in that the second shaft (16), in particular at its end (26) facing away from the first shaft (12), has a preferably conically shaped plug element (28) in order to prevent leakage of lubricant, in particular from the end (26) of the second shaft (16) facing away from the first shaft (12).

4. Drive arrangement (10) according to one of the preceding claims, characterized in that the first shaft (12) has on its outer side (30) at least one lubricant groove (32) for the targeted guidance of lubricant, in particular oil, on the outer side (30) of the first shaft (12).

5. Drive arrangement (10) according to one of the preceding claims, characterized in that the first shaft (12) and the second shaft (16), in particular in the region of the spline (22), are mounted by means of a bearing (34), wherein the bearing (34) comprises a bearing inner ring (36), wherein the bearing inner ring (36) contacts the first shaft (12) and the second shaft (16), wherein the bearing inner ring (36) has at least one lubricant opening (38) for the targeted conduction of lubricant, in particular oil, through the bearing inner ring (36).

6. Drive arrangement (10) according to one of the preceding claims, characterized in that a radial shaft sealing ring (40) is arranged on the first shaft (12).

7. Drive arrangement (10) according to one of the two preceding claims, characterized in that the drive arrangement (10) has a lubricant guide ring (42) for the targeted guidance of lubricant, in particular oil, to the bearing (34) and / or to the radial shaft sealing ring (40).

8. Drive arrangement (10) according to one of the preceding claims, characterized in that the first toothing (14) of the first shaft (12) is designed as an external toothing (44) and the second toothing (18) of the second shaft (16) is designed as an internal toothing (46).

9. Drive arrangement (10) according to one of claims 1 to 7, characterized in that the first shaft (12) is designed as a hollow shaft, the first toothing (14) of the first shaft (12) is designed as an internal toothing and the second toothing (18) of the second shaft (16) is designed as an external toothing.

10. Vehicle, in particular motor vehicle, with at least one drive arrangement (10) according to one of the preceding claims.