Coupling element and transmission having coupling element

Abstract

A coupling element and a transmission having the coupling element are provided. The coupling element (30) comprises an inner toothing, an outer toothing and a recess (32). The coupling element (30) is designed in an annular manner. Inner teeth are formed at the inner periphery and outer teeth are formed at the outer periphery. At least one recess (32) is formed at at least one first end region of the internal tooth portion in the axial direction.

Description

Technical Field

[0001] The invention relates to a coupling element and to a transmission having a coupling element. Background Art

[0002] WO2005 / 120877 A1 shows a coupling element for mechanically coupling a first planetary gear set to a second planetary gear set. The coupling element includes a ring gear at the inner periphery, and the ring gear engages with the planetary gears located on the inner side in the radial direction. Summary of the invention

[0003] The object of the present invention is to provide an improved coupling element which increases the efficiency and lubrication function of the transmission during operation.

[0004] This object is achieved by a coupling element having the features of claim 1 .

[0005] The coupling element comprises an inner toothing, an outer toothing and a recess. The coupling element is constructed in an annular manner. The inner toothing is formed at the inner periphery. The outer toothing is formed at the outer periphery. Therefore, the inner toothing is connected to the outer toothing in a torsion-proof manner. At least one recess is formed at at least one first end region in the axial direction. The first end region can be arranged at the inner toothing. At least one recess can be arranged at a second end region opposite to the first end region in the axial direction. The second end region can be arranged at the inner toothing.

[0006] If two elements are connected to each other, the movement of one element causes a reaction of the other element. For example, the connection can be provided by a form-fitting or friction-fitting connection. Additional elements can be provided between the elements. For example, the connection can be torsion-proof. A torsion-proof connection of two elements is understood to mean a connection in which the two elements are rigidly connected to each other in all expected states, for example in all expected states of a transmission, so that they have essentially the same rotational speed. In this case, the elements can exist as separate components connected to each other in a torsion-proof manner or as a single piece.

[0007] In an embodiment, the coupling element may comprise a circumferential groove formed at an inner circumference of the coupling element.The groove may be arranged at a first end region of the coupling element.

[0008] The recess may overlap with the groove base of the groove in the radial direction. The groove base may be the outer cylindrical surface of the groove in the radial direction. The recess may extend from the groove base at least partially in the radial direction. Therefore, the recess may form at least one small step outward from the groove base in the radial direction. There may be two grooves. Each groove may be arranged at one end region of the two end regions of the coupling element that are opposite to each other in the axial direction.

[0009] In an embodiment, the recess may extend from the groove in a radial direction through the coupling element to an outer side of the coupling element.

[0010] In an embodiment, the recess may extend from the groove in the axial direction through the coupling element to the outside of the coupling element.The recess may extend obliquely, that is to say in the radial direction and in the axial direction, through the coupling element to the outside of the coupling element.

[0011] In an embodiment, the groove may be formed by a through hole. The hole may start from the groove base. The hole may extend obliquely, that is to say extend through the coupling element in radial and axial directions to the outside of the coupling element. The diameter of the hole may be smaller than the width of the groove.

[0012] In an embodiment, the recess may have a surface that curves outwardly in a radial direction. The curved surface may be a cylindrical surface. The curved surface may extend from the inner circumference of the coupling element in a radial direction beyond the groove base. The curved surface may be part of a hole. The hole may be produced by drilling or face milling in an axial direction. The center point of the hole may be arranged in the inner circumference of the coupling element in a radial direction.

[0013] In an embodiment, the recess may have a rectangular cross section in the circumferential direction. The recess may be produced by a face milling cutter that moves in the radial direction and is aligned in the axial direction. The recess may completely cover the groove in the axial direction. The recess may completely cover the groove in the radial direction.

[0014] In an embodiment, a plurality of recesses may be provided. The recesses may be evenly distributed in the circumferential direction. An even number of recesses may be provided at each end region of the coupling element. More than three (e.g. eight) recesses may be provided at each end region of the coupling element. If a recess is provided at each of the two end regions of the coupling element, the same number of recesses may be provided at each end region, and the recesses of the two end regions may be provided at the same position in the circumferential direction.

[0015] In an embodiment, at least one of the outer toothing and the inner toothing may be helical-toothed.Both the outer toothing and the inner toothing may be helical-toothed.

[0016] In an embodiment, the oil space may be formed at the inner periphery of the coupling element. The oil space may be delimited in the axial direction by a delimiting surface. The delimiting surface may extend in the circumferential direction. The delimiting surface may be arranged in the axial direction at the end region of the inner tooth portion. The oil space may include the tooth portion of the first ring gear.

[0017] The groove may at least partially form a bounding surface. For example, a surface of the groove located on the outside in the axial direction may form a bounding surface. An oil space may extend between two grooves. An oil space may be formed between the groove base and a surface of the groove extending in the circumferential direction. During the intended use of the coupling element, a centrifugal force may act in a radial direction, which centrifugal force transports oil in a radial direction for lubricating the first ring gear.

[0018] The oil space can be defined by a second defining surface. The second defining surface can be arranged at a second end region opposite to the first end region. The second defining surface can be formed at least in part by a second groove. The oil space can extend inwardly to the center of the coupling element in the axial direction. The oil space can be arranged between the two defining surfaces in the axial direction. The oil space can always be defined by the groove base of the groove, the surface of the groove located outside in the axial direction, and the inner periphery of the coupling element.

[0019] In an embodiment, the oil space may be in fluid communication with at least one recess. The recess may be configured such that it enables oil flow from the oil space in a radial direction of the coupling element. The oil flow may occur from the oil space in a radial direction and in an axial direction. The recess may extend from the oil space in a radial direction of the coupling element.

[0020] If two elements are fluidically connected to each other, a fluid (e.g. oil) can be conducted from one element to the other element. In this case, the fluid connection can be constructed to be leak-free so that the oil is substantially completely conducted from one element to the other element.

[0021] One of the recesses may be configured so that it is in fluid communication with the surface of the oil space (the surface being located furthest outward in the radial direction). The recess may be in fluid communication with the groove base. This improves the drainage of oil from the oil space by centrifugal force.

[0022] One of the recesses may extend in the axial direction from the outside of the coupling element beyond the bounding surface. The recess may be configured such that it does not comprise an undercut in the radial direction. This facilitates the drainage of oil from the oil space by centrifugal force.

[0023] In an embodiment, the coupling element may be configured to couple a first gear set and a second gear set of the transmission. The first gear set may include at least a first ring gear. The second gear set may include at least a second spur gear. The coupling element may form a first ring gear at the inner periphery and a second spur gear at the outer periphery.

[0024] In an embodiment, the coupling element may include a fixing element configured to at least indirectly position the coupling element and at least one first planetary gear of the first gear set relative to each other in the axial direction. The first planetary gear may be engaged with the first ring gear. The surface of the fixing element located inside in the axial direction may at least partially form a delimiting surface of the oil space. The recess may extend in the axial direction from the outside of the coupling element to exceed the surface of the fixing element located inside in the axial direction. The fixing element may be formed by a snap ring or a fixing ring. The circumferential groove may be configured to position the fixing element in the axial direction.

[0025] In an embodiment, a thrust washer may be provided between the coupling element and the first planetary gear for relative positioning of the coupling element and the first planetary gear. The thrust washer may be configured to contact the inner surface of the fixed element. The thrust washer may be configured for axial positioning of the first planetary gear. The inner surface of the thrust washer in the axial direction may at least partially form a delimiting surface of the oil space. The inner surface of the thrust washer may be configured in a convex manner toward the inner side in the axial direction. When the thrust washer contacts the first planetary gear, line contact may occur.

[0026] The recess can extend in the axial direction from the outer side of the coupling element beyond the surface of the thrust washer which is located on the inner side in the axial direction.The thrust washer and the fixing ring can be designed as a one-piece element.

[0027] In one aspect, the invention relates to a transmission having a first gear set, a second gear set and a coupling element according to one of the preceding embodiments. The first gear set comprises a first ring gear. The second gear set comprises a second spur gear.

[0028] In an embodiment, the first gear set may be formed by a first planetary gear set, which may include a first sun gear, a first planet carrier, a first planet gear and a first ring gear. The first planet gear may form a first spur gear. The first sun gear may engage with the first planet gear.

[0029] In an embodiment, the second gear set may be formed by a second planetary gear set. The second planetary gear set may include a second sun gear, a second planet carrier, a second planetary gear and a second ring gear. The second sun gear may form a second spur gear. Then, the coupling element forms a sun ring gear. The second sun gear may engage with the second planetary gear. The second planetary gear may engage with the second ring gear. The first planetary gear set and the second planetary gear set may be arranged in the same plane in the axial direction. The first planetary gear set and the second planetary gear set may be arranged to be offset in the axial direction relative to each other.

[0030] The transmission may have the function of a differential gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A perspective view of an embodiment of a coupling element is shown.

[0032] Figure 2 A cross-sectional view of another embodiment of a coupling element is shown.

[0033] Figure 3 A side view of another embodiment of a coupling element is shown.

[0034] Figure 4 A cross-sectional view of an embodiment of a transmission having a coupling element is shown.

[0035] Figure 5 A cross-sectional view of an embodiment of a transmission with a coupling element is shown in detail. DETAILED DESCRIPTION

[0036] Figure 1 1 shows a cross-sectional view of an embodiment of a coupling element 30. The coupling element 30 is constructed in an annular manner. The coupling element 30 forms an internal toothing at the inner circumference, in this case the first ring gear 14 of the first gear set. The first ring gear 14 is constructed to Figure 1 The coupling element 30 forms an external toothing at the outer circumference, in this case a second spur gear of the second gear set formed as a second sun gear 21. The first ring gear 14 and the second spur gear are helically toothed, wherein the teeth of the first ring gear 14 and the second spur gear are arranged obliquely in the same direction relative to the circumferential direction of the coupling element 30.

[0037] In its intended use, the first ring gear 14 is lubricated and cooled by oil. The circumferential grooves 31 are each provided at opposite end regions in the axial direction of the inner circumference of the coupling element 30. Therefore, the coupling element 30 comprises two grooves 31. Each circumferential groove 31 is configured to receive a fixing ring. The grooves 31 each have a surface which is located on the outside in the axial direction, extends in the circumferential direction, and respectively forms a delimiting surface for the oil space 33. In the intended use of the coupling element 30, the oil is delivered to the oil space 33 by centrifugal force or in another way.

[0038] Eight recesses 32 are provided at each end region. Each recess 32 has a rectangular cross section. Each recess 32 extends from the inner surface extending in the circumferential direction to the outside of the coupling element 30 in the axial direction, respectively, until the outside of the coupling element 30. Each recess 32 extends from the groove base of the groove 31 to the outside of the coupling element 30 in the radial direction until the outside. In other words, each recess 32 completely overlaps with the groove 31 in the axial direction and in the radial direction. Each recess 32 is configured so that oil can flow out of the oil space 33 to the outside.

[0039] Figure 2 FIG. 2 shows a cross-sectional view of another embodiment of a coupling element 30. In this embodiment, the configuration of the recess 32 is different from that of the embodiment described above. Figure 1 The recess 32 is described.

[0040] In the present case, one of the recesses 32 is formed by a cylindrical hole. The cylindrical hole extends from the groove base in the radial direction to the outside. The diameter of the cylindrical hole is smaller than the width of one of the grooves 31. The cylindrical hole is positioned in one of the grooves 31 in the axial direction.

[0041] Figure 3 1 shows a side view of another embodiment of a coupling element 30. In this embodiment, the configuration of the recess 32 is different from that of the Figure 1 The recess 32 is described.

[0042] In the present case, one of the recesses 32 is formed by a surface extending in the axial direction and curved outward in the radial direction. The curved surface extends in the radial direction from the inside of the coupling element 30 beyond the groove base of the corresponding one groove 31. The curved surface extends in the axial direction from the groove base to the outside of the coupling element 30.

[0043] Figure 4 It shows that Figure 1 sectional view of an embodiment of a transmission with a coupling element 30 described. The transmission has a first planetary gear set 10 and a second planetary gear set 20. The first planetary gear set 10 includes a first planet carrier 12, a plurality of first planetary gears 13, and a first ring gear 14. The first planetary gears 13 are rotatably supported in the first planet carrier 12. The second planetary gear set 20 includes a second sun gear 21. The second sun gear 21 forms a second spur gear. Therefore, the coupling element 30 is configured as a sun ring gear, which forms the first ring gear 14 at its inner periphery and the second sun gear 21 at its outer periphery.

[0044] In each groove 31, a fixing element 40 configured as a fixing ring is arranged accordingly. Between one of the fixing elements 40 and one of the first planetary gears 13, thrust washers 50 are arranged on both sides of the first planetary gear 13 in the axial direction accordingly. When the coupling element 30 is used as intended, at least one of the first planetary gears 13 abuts against at least one of the thrust washers 50. Therefore, the first planetary gears 13 are positioned within the first ring gear 14 in the axial direction.

[0045] The surface of each fixing element 40 located inside in the axial direction and extending in the circumferential direction at least partially forms a delimiting surface of the oil space 33. The surface of each thrust washer 50 located inside in the axial direction and extending in the circumferential direction at least partially forms a delimiting surface of the oil space 33. In particular, the oil space 33 is delimited by the inner periphery of the coupling element 30, the groove base of the groove 31, the surface of the fixing element 40 located inside in the axial direction, and the surface of the thrust washer 50 located inside in the axial direction, respectively.

[0046] The oil in the oil space 33 between the thrust washer 50 and the inner periphery of the coupling element 30 is always transferred into one of the grooves 31 by centrifugal force. The oil can flow out from each groove 31 through the recess 32 to the outside.

[0047] In an alternative embodiment, one of the recesses 32 is each as described with respect to Figure 2 and Figure 3 Constructed as described.

[0048] Figure 5 The detailed description shows that Figure 3 sectional view of an embodiment of a transmission of the coupling element 30 described. In other aspects, the present embodiment includes Figure 4 The arcuate surface of one of the recesses 32 ends in the axial direction within the coupling element 30 in the region between the axially inner surface of one of the fixing elements 40 and the axially inner surface of one of the grooves 31 .

[0049] Reference numerals

[0050] 10First planetary gear set

[0051] 12First planet carrier of the first planetary gear set

[0052] 13 First planetary gear of the first planetary gear set

[0053] 14First ring gear of the first planetary gear set

[0054] 20 Second planetary gear set

[0055] 21 The second sun gear of the second planetary gear set

[0056] 30Connection element

[0057] 31 grooves

[0058] 32 recess

[0059] 33 Oil Space

[0060] 40Fixing elements

[0061] 50 thrust washer

Claims

1. A coupling element (30), comprising an inner toothing, an outer toothing and a recess (32), wherein: The coupling element (30) is constructed in an annular manner, The inner teeth portion is formed at the inner periphery and the outer teeth portion is formed at the outer periphery, and At least one recess (32) is formed at at least one first end region in the axial direction.

2. The coupling element (30) according to claim 1, characterized in that A circumferential groove (31) is formed at the inner circumference at the first end region.

3. The coupling element (30) according to claim 2, characterized in that The recess (32) extends from the groove (31) in a radial direction through the coupling element (30) to the outer side of the coupling element (30).

4. The coupling element (30) according to claim 2 or 3, characterized in that The recess (32) extends from the groove (31) in the axial direction through the coupling element (30) to the outer side of the coupling element (30).

5. Coupling element (30) according to one of the preceding claims, characterized in that The recess (32) is formed by a through hole.

6. Coupling element (30) according to one of claims 1 to 4, characterized in that The recess (32) includes a surface that curves outward in the radial direction.

7. The coupling element (30) according to one of claims 1 to 4, characterized in that The recess (32) includes a rectangular cross-section in the circumferential direction.

8. Coupling element (30) according to one of the preceding claims, characterized in that A plurality of recesses (32) are provided.

9. Coupling element (30) according to one of the preceding claims, characterized in that At least one of the inner tooth portion and the outer tooth portion is helically toothed.

10. Coupling element (30) according to one of the preceding claims, characterized in that An oil space (33) is formed at the inner periphery of the coupling element (30), The oil space (33) is delimited in the axial direction by a delimiting surface, and The groove (31) at least partially forms the delimiting surface.

11. The coupling element (30) according to claim 10, characterized in that The oil space (33) is in fluid communication with at least one of the recesses (32), and At least one of the recesses (32) is configured such that it enables oil to flow from the oil space (33) in the radial direction.

12. The coupling element (30) according to claim 11, characterized in that The coupling element (30) is configured to couple a first gear set and a second gear set of the transmission. The first gear set comprises at least one first ring gear (14), The second gear set includes at least one second spur gear, and The coupling element (30) forms the first ring gear (14) at the inner periphery and the second spur gear at the outer periphery.

13. The coupling element (30) according to claim 12, characterized in that The coupling element (30) comprises a fixing element (40), The fixing element (40) is configured to at least indirectly position the coupling element (30) and at least one first planetary gear (13) of the first gear set relative to each other in the axial direction, and The surface of the fixing element (40) located on the inner side in the axial direction at least partially forms a delimiting surface of the oil space (33).

14. The coupling element (30) according to claim 13, characterized in that A thrust washer (50) is provided between the coupling element (30) and the first planetary gear (13) for relative positioning of the coupling element (30) and the first planetary gear (13), and The surface of the thrust washer (50) located on the inner side in the axial direction at least partially forms a boundary surface of the oil space (33).

15. A transmission having a first gear set, a second gear set and a coupling element (30) according to one of claims 1 to 14, characterized in that The first gear set includes the first ring gear (14), and The second gear set includes the second spur gear.

16. The transmission according to claim 15, characterized in that The first gear set is formed by a first planetary gear set (10), the first planetary gear set (10) comprising a first sun gear, a first planet carrier (12), a first planetary gear (13) and the first ring gear (14), wherein The first sun gear is engaged with the first planetary gears (13).

17. The transmission according to claim 15 or 16, characterized in that The second gear set is formed by a second planetary gear set (20), the second planetary gear set (20) comprising a second sun gear (21), a second planet carrier, second planetary gears and a second ring gear, wherein The second sun gear (21) forms the second spur gear, the second sun gear (21) is engaged with the second planetary gears, and the second planetary gears are engaged with the second ring gear.

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