Traction drive for a motor vehicle transmission

Abstract

A flexible traction drive mechanism for a motor vehicle transmission includes a first traction mechanism wheel which can be rotationally fixed to a first transmission component, a second traction mechanism wheel which is drivingly connected to the first traction mechanism wheel by a traction mechanism and can be rotationally fixed to a second transmission component, and a bearing journal for supporting the first traction mechanism wheel. The first traction mechanism wheel is arranged so as to be axially movable relative to the bearing journal.

Claims

1. A flexible traction drive mechanism (1) for a motor vehicle transmission (2), comprising: a first traction mechanism wheel (3) rotationally fixable to a first transmission component (8); a second traction mechanism wheel (4) drivingly connected to the first traction mechanism wheel (3) by a traction mechanism (5), the second traction mechanism wheel (4) rotationally fixable to a second transmission component (7); and a bearing journal (6) supporting the first traction mechanism wheel (3), wherein the first traction mechanism wheel (3) is arranged such that the first traction mechanism wheel (3) is axially movable relative to the bearing journal (6), and wherein the bearing journal (6) is rotatably fixed relative to a transmission housing (9).

2. The flexible traction drive mechanism (1) of claim 1, wherein a diameter of the first traction mechanism wheel (3) is smaller than a diameter of the second traction mechanism wheel (4).

3. The flexible traction drive mechanism (1) of claim 1, wherein: the bearing journal (6) and the transmission housing (9) are a single piece; the bearing journal (6) comprises a fastening portion (19) which is removably connected, in a form-fit and/or friction-locking manner, to another fastening portion (20) of the transmission housing (9); or the flexible traction drive mechanism (1) comprises a connecting mechanism (27) which is at least partially enclosed by the bearing journal (6), the connecting mechanism (27) is removably connected to the bearing journal (6), and the bearing journal (6) is connectable to the transmission housing (9) in a form-fit and/or friction-locking manner with the connecting mechanism (27).

4. The flexible traction drive mechanism (1) of claim 1, further comprising a bearing (10), the first traction mechanism wheel (3) radially supported against the bearing journal (6) by the bearing (10).

5. The flexible traction drive mechanism (1) of claim 4, further comprising a thrust race (12) for the first traction mechanism wheel (3).

6. The flexible traction drive mechanism (1) of claim 5, wherein the bearing (10) rests directly on the bearing journal (6), and the thrust race (12) is integral with the bearing journal (6).

7. The flexible traction drive mechanism (1) of claim 5, further comprising a bush (11) that at least partially encloses the bearing journal (6), wherein the bearing (10) is radially supported on the bearing journal (6) by the bush (11), and the thrust race (12) is integral with the bush (11).

8. The flexible traction drive mechanism (1) of claim 7, wherein the bush (11) comprises a radially outwardly protruding collar (13), and the thrust race (12) is formed on the radially outwardly protruding collar (13).

9. The flexible traction drive mechanism (1) of claim 4, wherein an oil line (15) extends axially through the bearing journal (6), and oil from the oil line (15) is flowable through at least one bore hole (14) to the bearing (10).

10. The flexible traction drive mechanism (1) of claim 9, further comprising an oil guide member (24), wherein the oil guide member (24) is arranged and configured such that the oil guide member (24) diverts the oil which flows through the bearing (10) towards the traction mechanism (5).

11. The flexible traction drive mechanism (1) of claim 9, further comprising an oil guide member (24), wherein the oil guide member (24) is arranged on an end of a radially outwardly protruding collar (13) of a bush (11) that at least partially encloses the bearing journal (6), and the bearing (10) is radially supported on the bearing journal (6) by the bush (11).

12. The flexible traction drive mechanism (1) of claim 9, further comprising an oil guide member (24), wherein the oil guide member (24) is arranged on one or both of the bearing journal (6) and the transmission housing (9).

13. The flexible traction drive mechanism (1) of claim 9, wherein the first traction mechanism wheel (3) comprises at least one other bore hole (25) and an additional oil guide member (26), the at least one other bore hole (25) configured such that the oil which has flowed through the bore hole (14) flows out of the first traction mechanism wheel (3) through the at least one other bore hole (25), the additional oil guide member (26) configured to divert the oil which has flowed through the at least one other bore hole (25) towards the traction mechanism (5).

14. The flexible traction drive mechanism (1) of claim 9, wherein the first traction mechanism wheel (3) comprises at least one additional bore hole (33) through which the oil which has flowed through the bore hole (14) flows out of the first traction mechanism wheel (3) and through the first traction mechanism wheel (3) directly to a traction mechanism toothing formed on the first traction mechanism wheel (3).

15. A motor vehicle transmission (2) comprising the flexible traction drive mechanism (1) of claim 1, wherein the first traction mechanism wheel (3) is rotationally fixed to the first transmission component (8) and the second traction mechanism wheel (4) is rotationally fixed to the second transmission component (7).

16. The motor vehicle transmission (2) of claim 15, wherein the first transmission component (8) is a rotor shaft of an electric motor (16).

17. The motor vehicle transmission (2) of claim 16, wherein the second transmission component (7) is a shaft which is rotationally fixed to the second traction mechanism wheel (4) or is a clutch component.

18. The motor vehicle transmission (2) of claim 15, wherein the second transmission component (7) is a shaft which is rotationally fixed to the second traction mechanism wheel (4) or is a clutch component.

19. The motor vehicle transmission (2) of claim 15, wherein the first transmission component (8) is radially offset from the second transmission component (7).

20. A motor vehicle, comprising the flexible traction drive mechanism (1) of claim 1.

21. A motor vehicle, comprising the motor vehicle transmission (2) of claim 15.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The subject of the invention is schematically represented in the figures and is described in the following with reference to the figures, wherein identical or identically operating elements are mostly provided with the same reference characters. Wherein:

(2) FIG. 1 shows a sectioning of the transmission according to the invention including the flexible traction drive mechanism according to the invention, according to a first exemplary embodiment,

(3) FIG. 2 shows an enlarged representation of one part of the flexible traction drive mechanism according to the invention, according to the first exemplary embodiment,

(4) FIG. 3 shows an enlarged representation of one part of a flexible traction drive mechanism according to the invention, according to a second exemplary embodiment,

(5) FIG. 4 shows an enlarged representation of one part of a flexible traction drive mechanism according to the invention, according to a third exemplary embodiment,

(6) FIG. 5 shows an enlarged representation of one part of a flexible traction drive mechanism according to the invention, according to a fourth exemplary embodiment, and

(7) FIG. 6 shows a motor vehicle including the flexible traction drive mechanism according to the invention.

DETAILED DESCRIPTION

(8) Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

(9) FIG. 1 shows one part of a motor vehicle transmission 2 including a flexible traction drive mechanism 1. The flexible traction drive mechanism 1 includes a first traction mechanism wheel 3 which is rotationally fixed to a first transmission component 8. The first transmission component 8 is a rotor shaft of an electric machine 16. The flexible traction drive mechanism 1 includes a bearing journal 6 for supporting the first traction mechanism wheel 3. The first traction mechanism wheel 3 is arranged so as to be axially movable relative to the bearing journal 6. The bearing journal 6 is designed as a single piece with a transmission housing 9. In this case, the bearing journal 6 protrudes in the axial direction from an inner wall of the transmission housing 9.

(10) In addition, the flexible traction drive mechanism 1 includes a second traction mechanism wheel 4 which is drivingly connected to the first traction mechanism wheel 3 by a traction mechanism 5 in the form, for example, of a chain. The second traction mechanism wheel 4 is rotationally fixed to a second transmission component 7. The second transmission component 7 is a clutch component which is not represented in greater detail in FIG. 1, such as a disk carrier, a dual clutch, a triple clutch, a torque converter, or a clutch housing. The second transmission component 7 can move axially during operation of the transmission 2.

(11) The second transmission component 7 is drivingly connected to a transmission input shaft 22. The transmission input shaft 22 is drivingly connected to a motor vehicle drive unit VM, such as an internal combustion engine. In addition, the transmission input shaft 22 is drivingly connected to at least one integral part of a main transmission HG. The main transmission HG includes, for example, gear sets and shift elements which are not represented in greater detail in FIG. 1. A transmission output shaft 18 is drivingly connected at least to one of the integral parts of the main transmission HG. By controlling one or more of the shift elements of the main transmission HG, multiple gears, each having a different ratio, between the transmission input shaft 22 and the transmission output shaft 18 can be implemented.

(12) The design represented in FIG. 1 is to be considered merely as an example. A separating clutch, a dual clutch, a triple clutch, or a torque converter including a torque converter lockup clutch can be additionally arranged between the motor vehicle drive unit VM and the second transmission component. The transmission output shaft 18 and the transmission input shaft 22 can be arranged on the same axial end of the main transmission HG. The transmission output shaft 18 and the transmission input shaft 22 can have axes of rotation that differ from one another, as in the case, for example, of a transmission for a front-transverse drive or a rear-transverse drive of a motor vehicle. The design represented in FIG. 1 therefore serves merely as an example, and does not limit the design of the flexible traction drive mechanism according to the invention.

(13) The electric machine 16 and the second transmission component 7 are offset with respect to each other in the radial direction relative to a central axis M of the transmission 2.

(14) FIG. 2 shows an enlarged representation of one part of the flexible traction drive mechanism 1. The flexible traction drive mechanism 1 includes a bearing 10, by which the first traction mechanism wheel 3 is supported on the bearing journal 6 in the radial direction. The bearing 10 is a needle bearing which permits an axial movement of the first traction mechanism wheel 3 relative to the bearing journal 6.

(15) The bearing 10 rests directly on a bush 11 which encloses a part of the bearing journal 6 and is arranged radially between the bearing 10 and the bearing journal 6. The bush 11 includes, at one end, a circumferential, radially protruding collar 13 which acts as a thrust race 12 for axially supporting the first traction mechanism wheel 3.

(16) The bearing journal 6 includes an oil line 15. One end of the oil line 15 is fluidically connected to yet another oil line 32 of the transmission 1. The further oil line 32 is arranged within the transmission housing 9 and/or is fluidically connected to a main oil line (not represented). By the main oil line, not only the electric machine 16, but also further components of the transmission 2, which are not represented in the figures, are supplied with oil. The oil line 15 opens, at its other end, in a cavity 21 enclosed by the first traction mechanism wheel 3. The cavity 21 is partially delimited by a coupling portion 30 of the first traction mechanism wheel 3. The coupling portion 30 is an integral part of the first traction mechanism wheel 3 and is rotationally fixed to the rotor shaft.

(17) The bearing journal 6 includes a bore hole 14, through which the oil located in the oil line 15 flows into an accommodating chamber 23 delimited by the first traction mechanism wheel 3. One portion of the oil which has flowed into the accommodating chamber 23 subsequently flows through the bearing 10 to the collar 13. The collar 13 includes, at one end, an oil guide member 24 which is configured for diverting the oil which has flowed through the bearing 10 in the direction of the traction mechanism 5.

(18) The first traction mechanism wheel 3 also includes at least one other bore hole 25, through which a portion of the oil which has flowed into the accommodating chamber 23 flows out of the first traction mechanism wheel 3. The first traction mechanism wheel 3 includes yet another oil guide member 26 which is designed and arranged in such a way that it diverts the oil which has flowed out of the other bore hole 25 in the direction of the traction mechanism 5. As a result, the traction mechanism 5 can be cooled and lubricated.

(19) Optionally, at least one additional bore hole 33 is provided in the first traction mechanism wheel 3. One portion of the oil which has flowed into the accommodating chamber 23 can be directly guided to the traction mechanism toothing formed on the traction mechanism wheel 3 through the at least one additional bore hole 33.

(20) FIG. 3 shows an enlarged representation of one part of the flexible traction drive mechanism 1 according to a second exemplary embodiment. The represented flexible traction drive mechanism 1 differs from the flexible traction drive mechanism 1 represented in FIG. 1 in that the bearing journal 6 and the transmission housing 9 are not designed as a single piece, but rather as two pieces.

(21) The bearing journal 6 is breakably connected to the transmission housing 9 by a connecting mechanism 27 in the form of a hollow screw. The connecting mechanism 27 includes, at one end, an external thread which is engaged with an internal thread of the transmission housing 9. In addition, the connecting mechanism 27 includes a circumferential projection 31 which, in the assembled condition of the flexible traction drive mechanism 1, presses the bearing journal 6 against the transmission housing 9. The connecting mechanism 27 includes one part of the oil line 15.

(22) Yet another difference is that, in the exemplary embodiment according to FIG. 3, a coupling piece 28 is present, which includes the bore hole 14 and another part of the oil line 15. In this case, one end of the coupling piece 28 is connected to the connecting mechanism 27 and is arranged downstream from the connecting mechanism 27. Another end of the coupling piece 28 protrudes into the cavity 21. In particular, the coupling piece 28 is arranged and designed in such a way that the other part of the oil line 15 is fluidically connected to the cavity 21. The coupling piece 28 prevents all the oil from flowing out of the connecting mechanism 27 into the accommodating chamber 23. The coupling piece 28, the connecting mechanism 27, and the bearing journal 6 are arranged coaxially to each other. The further oil line 32 is not represented in FIG. 3.

(23) Yet another difference is that the flexible traction drive mechanism 1 according to the exemplary embodiment represented in FIG. 3 does not include a bush 11. In this case, the bearing journal 6 includes a support area 29 which forms the thrust race 12 for axially supporting the first traction mechanism wheel 3. The support area 29 projects in the radial direction away from the remaining bearing journal 6. The flexible traction drive mechanism according to FIG. 3 can nevertheless include—as shown in FIG. 2—at least one additional bore hole 33 and/or at least one of the oil guide members 24, 26. The oil guide member 24 can be formed, for example, on the bearing journal 6.

(24) FIG. 4 shows an enlarged representation of one part of the flexible traction drive mechanism 1 according to a third exemplary embodiment. The represented flexible traction drive mechanism 1 differs from the flexible traction drive mechanism 1 represented in FIG. 3 in the design of the connecting mechanism 27, in particular in the connection of the connecting mechanism 27 to the transmission housing 9 and to the bearing journal 6.

(25) The connecting mechanism 27 shown in FIG. 4, for example, is connected to the bearing journal 6 by a bolted connection. In the assembled condition of the flexible traction drive mechanism 1, the projection 31 of the connecting mechanism 27 rests against the transmission housing 9; the seal is implemented by an O-ring 34. The oil line 15 is connected to yet another oil line 32 (not represented), wherein the further oil line 32 is not arranged in the transmission housing 9.

(26) The flexible traction drive mechanism according to FIG. 4 can nevertheless include—as shown in FIG. 2—at least one additional bore hole 33 and/or at least one of the oil guide members 24, 26. The oil guide member 24 can be formed, for example, on the bearing journal 6.

(27) FIG. 5 shows an enlarged representation of one part of the flexible traction drive mechanism 1 according to a fourth exemplary embodiment. The represented flexible traction drive mechanism 1 differs from the flexible traction drive mechanism 1 represented in FIG. 1 in that the bearing journal 6 and the transmission housing 9 are not designed as a single piece, but rather as two pieces.

(28) For example, the bearing journal 6 can be re-breakably connected, in particular bolted, to another fastening portion 20 of the transmission housing 9 by a fastening portion 19. The fastening portion 19 and the other fastening portion 20 each include a thread. The further oil line 32 is not represented in FIG. 5.

(29) Yet another difference is that the flexible traction drive mechanism 1 according to the exemplary embodiment represented in FIG. 5 does not include a bush 11. The thrust race 12 is therefore an integral part of the bearing journal 6.

(30) The flexible traction drive mechanism according to FIG. 5 can nevertheless include—as shown in FIG. 2—at least one additional bore hole 33 and/or at least one of the oil guide members 24, 26. The oil guide member 24 can be formed, for example, on the bearing journal 6.

(31) FIG. 6 shows a motor vehicle 17 including the motor vehicle transmission 2 according to the invention. As is apparent from FIG. 6, the motor vehicle transmission 2 is drivingly connected to the motor vehicle drive unit VM. The motor vehicle transmission 2 can be drivingly connected by the transmission output shaft 18 to other components of the motor vehicle 17, such as an axle differential which is not represented in the figures.

(32) Modifications and variations can be made to the embodiments illustrated or described herein without departing from the scope and spirit of the invention as set forth in the appended claims.

REFERENCE CHARACTERS

(33) 1 flexible traction drive mechanism 2 motor vehicle transmission 3 first traction mechanism wheel 4 second traction mechanism wheel 5 traction mechanism 6 bearing journal 7 second transmission component 8 first transmission component 9 transmission housing 10 bearing 11 bush 12 thrust race 13 collar 14 bore hole 15 oil line 16 electric machine 17 motor vehicle 18 transmission output shaft 19 fastening portion 20 other fastening portion of the transmission housing 21 cavity 22 transmission input shaft 23 accommodating chamber 24 oil guide member 25 other bore hole 26 further oil guide member 27 connecting mechanism 28 coupling piece 29 support area 30 coupling portion 31 projection 32 further oil line 33 additional bore hole 34 O-ring M central axis HG main transmission VM motor vehicle drive unit