Planetary Gearset System for a Motor-Vehicle Transmission, Transmission for a Motor Vehicle Having Such a Planetary Gearset System, and Drive Train for a Motor Vehicle

Abstract

A planetary gear set system (PS, PS2) for a motor vehicle transmission (G), wherein the planetary gear set system (PS) comprises either three planetary gear sets (P1, P2, P3) or one Ravigneaux gear set (PR), and one additional planetary gear set (P23), a transmission (G) for a motor vehicle comprising such a planetary gear set system (PS, PS2), as well as a drive train for a motor vehicle comprising such a transmission (G).

Claims

1-17: (canceled)

18. A planetary gear set system (PS) for a motor vehicle transmission (G), comprising: a first planetary gear set (P1) that is a minus gear set, a carrier (E21) of the first planetary gear set (P1) is permanently rotationally fixed; a second planetary gear set (P2) that is a minus gear set, a sun gear (E11) of the first planetary gear set (P1) is permanently rotationally fixed to a ring gear (E32) of the second planetary gear set (P2), a carrier (E22) of the second planetary gear set (P2) is permanently rotationally fixed, the second planetary gear set (P2) is situated radially within the first planetary gear set (P1); and a third planetary gear set (P3); wherein the ring gear (E32) of the second planetary gear set (P2) forms a ring gear of the third planetary gear set (P3).

19. The planetary gear set system (PS) of claim 18, wherein the third planetary gear set (P3) is a plus gear set.

20. The planetary gear set system (PS) of claim 18, wherein neither a sun gear (E13) of the third planetary gear set (P3) nor a carrier (E23) of the third planetary gear set (P3) is permanently rotationally fixed to one of the gears (E11, E21, E31, E12, E22, E32) of the first planetary gear set (P1) and the second planetary gear set (P2).

21. A planetary gear set system (PS2) for a motor vehicle transmission (G), comprising: a Ravigneaux gear set (PR) with precisely four shafts; an additional planetary gear set (P23) which is a plus gear set, wherein a ring gear (E233) of the additional planetary gear set (P23) is permanently rotationally fixed to a sun gear (PR1) of the Ravigneaux gear set (PR), the sun gear (PR1) of the Ravigneaux gear set (PR) that intermeshes with radially outer planet gears of the Ravigneaux gear set (PR), and the additional planetary gear set (P23) is arranged radially within the sun gear (PR1) of the Ravigneaux gear set (PR).

22. A transmission (G) for a motor vehicle, comprising: the planetary gear set system (PS) of claim 18, an input shaft (GW1); an interface (GA) configured for power transmission from a transmission-external drive unit to the input shaft (GW1); and an output shaft (GW2), one section of the output shaft (GW2) comprising a tooth system (GW2A) configured for power transmission between the output shaft (GW2) and a transmission-internal or transmission-external differential gear (AG) arranged axially parallel to the output shaft (GW2).

23. The transmission (G) of claim 22, wherein the planetary gear set system (PS) forms the sole gear set system of the transmission (G) configured for implementing different gear ratios between the input shaft (GW1) and the output shaft (GW2).

24. The transmission (G) of claim 22, wherein the tooth system (GW2A) is arranged axially between the interface (GA) and the planetary gear set system (PS).

25. The transmission (G) of claim 22, wherein the tooth system (GW2A) is arranged axially between a bearing shield (LS) and the planetary gear set system (PS), and the bearing shield (LS) accommodates an antifriction bearing (GW2L) configured for radial and axial support of the output shaft (GW2).

26. The transmission (G) of claim 25, wherein a fourth shift element (D) is arranged radially within the antifriction bearing (GW2L).

27. The transmission (G) of claim 22, further comprising an electric machine (EM), wherein: the electric machine (EM) is arranged coaxially to the input shaft (GW1) and is permanently operatively connected to the input shaft (GW1); or the electric machine (EM) is arranged axially parallel to the input shaft (GW1) and is permanently operatively connected to the input shaft (GW1) via a spur gear drive (ST1, ST2, ST3) or via a flexible traction drive mechanism.

28. The transmission (G) of claim 22, further comprising a separating clutch (KO), wherein a shaft on which the interface (GA) is formed is connectable to the input shaft (GW1) with the separating clutch (KO).

29. A drive train for a motor vehicle, comprising: an internal combustion engine (VKM); the transmission (G) of claim 28; and a transmission-internal or transmission-external torsional vibration damper (TS); wherein the input shaft (GW1) of the transmission (G) is torsionally elastically connected via the transmission-internal or transmission-external torsional vibration damper (TS) to the internal combustion engine (VKM) either directly or via the separating clutch (KO), and driving wheels (DW) of the motor vehicle are connected to output shafts of the differential gear (AG).

30. The transmission (G) of claim 22, further comprising a plurality of shift elements with a first shift element (A), a second shift element (B), a third shift element (C), a fourth shift element (D), and a fifth shift element (E), wherein: a sun gear (E13) of the third planetary gear set (P3) is permanently connected to the input shaft (GW1); a ring gear (E31) of the first planetary gear set (P1) is permanently connected to the output shaft (GW2); the input shaft (GW1) is connectable to a sun gear (E12) of the second planetary gear set (P2) by engaging the first shift element (A); the third planetary gear set (P3) is a plus gear set; a carrier (E23) of the third planetary gear set (P3) is rotationally fixable by engaging the second shift element (B); the sun gear (E11) of the first planetary gear set (P1) is rotationally fixable by engaging the third shift element (C); the carrier (E21) of the first planetary gear set (P1) is rotationally fixable by engaging the fourth shift element (D); and the input shaft (GW1) is connectable to the carrier (E21) of the first planetary gear set (P1) by engaging the fifth shift element (E).

31. The transmission (G) of claim 30, wherein the second shift element (B) and the third shift element (C) are arranged axially between the interface (GA) and the tooth system (GW2A).

32. The transmission (G) of claim 30, wherein one or both of the first shift element (A) and the fifth shift element (E) is arranged axially between the planetary gear set system (PS) and an axial end of the transmission (G) opposite the interface (GA).

33. The transmission (G) of claim 30, wherein the second shift element (B) and the third shift element (C) are arranged axially between the planetary gear set system (PS) and an axial end of the transmission (G) opposite the interface (GA), and the first shift element (A) and the fifth shift element (E) are arranged axially between the interface (GA) and the planetary gear set system (PS).

34. A transmission (G) for a motor vehicle, comprising: the planetary gear set system (PS2) of claim 21, an input shaft (GW1); an interface (GA) configured for power transmission from a transmission-external drive unit to the input shaft (GW1); and an output shaft (GW2), one section of the output shaft (GW2) comprising a tooth system (GW2A) configured for power transmission between the output shaft (GW2) and a transmission-internal or transmission-external differential gear (AG) arranged axially parallel to the output shaft (GW2).

35. The transmission (G) of claim 34, wherein the planetary gear set system (PS2) forms the sole gear set system of the transmission (G) configured for implementing different gear ratios between the input shaft (GW1) and the output shaft (GW2).

36. The transmission (G) of claim 34, wherein the tooth system (GW2A) is arranged axially between the interface (GA) and the planetary gear set system (PS2).

37. The transmission (G) of claim 34, wherein the tooth system (GW2A) is arranged axially between a bearing shield (LS) and the planetary gear set system (PS2), and the bearing shield (LS) accommodates an antifriction bearing (GW2L) configured for radial and axial support of the output shaft (GW2).

38. The transmission (G) of claim 34, wherein a fourth shift element (D) is arranged radially within the antifriction bearing (GW2L).

39. The transmission (G) of claim 34, further comprising an electric machine (EM), wherein: the electric machine (EM) is arranged coaxially to the input shaft (GW1) and is permanently operatively connected to the input shaft (GW1); or the electric machine (EM) is arranged axially parallel to the input shaft (GW1) and is permanently operatively connected to the input shaft (GW1) via a spur gear drive (ST1, ST2, ST3) or via a flexible traction drive mechanism.

40. The transmission (G) of claim 34, further comprising a separating clutch (KO), wherein a shaft on which the interface (GA) is formed is connectable to the input shaft (GW1) with the separating clutch (KO).

41. A drive train for a motor vehicle, comprising: an internal combustion engine (VKM); the transmission (G) of claim 40; and a transmission-internal or transmission-external torsional vibration damper (TS); wherein the input shaft (GW1) of the transmission (G) is torsionally elastically connected via the transmission-internal or transmission-external torsional vibration damper (TS) to the internal combustion engine (VKM) either directly or via the separating clutch (KO), and driving wheels (DW) of the motor vehicle are connected to output shafts of the differential gear (AG).

42. The transmission (G) of claim 34, further comprising a plurality of shift elements with a first shift element (A), a second shift element (B), a third shift element (C), a fourth shift element (D), and a fifth shift element (E), wherein: a sun gear (E213) of the additional planetary gear set (P23) is permanently connected to the input shaft (GW1); a ring gear (PR3) of the Ravigneaux gear set (PR) is permanently connected to the output shaft (GW2); the input shaft (GW1) is connectable to a sun gear (PR4) of the Ravigneaux gear set (PR) that intermeshes with radially inner planet gears of the Ravigneaux gear set (PR) by engaging the first shift element (A); a carrier (E223) of the additional planetary gear set (P23) is rotationally fixable by engaging the second shift element (B); the sun gear (PR1) of the Ravigneaux gear set (PR) that intermeshes with the radially outer planet gears of the Ravigneaux gear set (PR) is rotationally fixable by engaging the third shift element (C); a carrier (PR2) of the Ravigneaux gear set (PR) is rotationally fixable by engaging the fourth shift element (D); and the input shaft (GW1) is connectable to the carrier (PR2) of the Ravigneaux gear set (PR) by engaging the fifth shift element (E).

43. The transmission (G) of claim 42, wherein one or both of the first shift element (A) and the fifth shift element (E) is arranged axially between the planetary gear set system (PS2) and an axial end of the transmission (G) opposite the interface (GA).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Exemplary embodiments of the invention are described in detail in the following with reference to the attached figures. Wherein:

[0031] FIG. 1 shows a schematic cutaway view of a motor vehicle drive train;

[0032] FIG. 2 through FIG. 7 show schematic cutaway views of various exemplary embodiments of a transmission;

[0033] FIG. 8 shows a structural cutaway view of a transmission;

[0034] FIG. 9 shows a shift pattern; and

[0035] FIG. 10 and FIG. 11 each show a planetary gear set system according to the invention.

DETAILED DESCRIPTION

[0036] 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.

[0037] FIG. 1 shows a schematic cutaway view of a motor vehicle drive train which includes a transmission G according to a first exemplary embodiment including a planetary gear set system PS. The transmission G includes, in addition to the planetary gear set system PS, an input shaft GW1, an output shaft GW2, a differential gear AG, a torsional vibration damper TS, a separating clutch KO, five shift elements A, B, C, D, E, as well as a rotationally fixed housing GG including a bearing shield LS attached thereto. The differential gear AG is connected to driving wheels DW of the motor vehicle via drive shafts.

[0038] The planetary gear set system PS includes a first planetary gear set P1, a second planetary gear set P2, and a third planetary gear set P3. The first planetary gear set P1 and the second planetary gear set P2 are each designed as a negative or minus gear set, while the third planetary gear set P3 is designed as a positive or plus gear set. A sun gear E13 of the third planetary gear set P3 is permanently connected to the input shaft GW1. A carrier E23 of the third planetary gear set P3 is rotationally fixable by engaging the second shift element B. A sun gear E12 of the second planetary gear set P2 is connectable to the input shaft GW1 by engaging the first shift element A. A carrier E22 of the second planetary gear set P2 is permanently rotationally fixed to a carrier E21 of the first planetary gear set P1 and is rotationally fixable by engaging the fourth shift element D. A ring gear E31 of the first planetary gear set P1 is permanently connected to the output shaft GW2.

[0039] A sun gear E11 of the first planetary gear set P1 is permanently rotationally fixed to a ring gear E32 of the second planetary gear set P2, wherein the ring gear E32 is formed on the inner diameter of the sun gear E11. The ring gear E32 also forms the ring gear of the third planetary gear set P3 in this case, and is designed to be appropriately wide. The ring gear E32, and the sun gear E11, is rotationally fixable by engaging the third shift element C.

[0040] The transmission G includes an interface GA to a transmission-external drive unit which can be designed, for example, as an internal combustion engine. The interface GA is configured for transmitting a rotational speed of the transmission-external drive unit to the input shaft GW1. A torsional vibration damper TS and a separating clutch KO are arranged between the interface GA and the input shaft GW1. The input shaft GW1 is connectable to the interface GA by engaging the separating clutch KO. An actuating element for actuating the separating clutch KO rests axially against a section of the input shaft GW1.

[0041] The output shaft GW2 includes, on one section, a tooth system GW2A which is utilized for the power transmission between the output shaft GW2 and the differential gear AG arranged axially parallel to the output shaft GW2. The tooth system GW2A is preferably designed to have oblique toothing and requires an appropriate mounting. The bearing shield LS is configured for accommodating an antifriction bearing GW2L which is utilized for the radial and axial support of the output shaft GW2.

[0042] The second shift element B and the third shift element C are located axially between the interface GA and the bearing shield LS. The output-shaft tooth system GW2A is located axially between the bearing shield LS and the planetary gear set system PS. The planetary gear set system PS is located axially between the output-shaft tooth system GW2A and the first shift element A, the fourth shift element D, and the fifth shift element E.

[0043] FIG. 2 shows a schematic view of a second exemplary embodiment of the transmission G which essentially corresponds to the first exemplary embodiment represented in FIG. 1. The remaining components of the drive train and the differential gear AG are not represented, for the sake of clarity. In this case, the transmission G includes an electric machine EM including a rotationally fixed stator S and a rotary rotor R which is arranged axially parallel to the input shaft GW1. The rotor R is operatively connected in a fixed transmission ratio to the input shaft GW1 via a spur gear drive ST1. The spur gear drive ST1 is arranged in the same plane as the separating clutch KO in this case. Instead of the spur gear drive ST1, a flexible traction drive mechanism could also be utilized, for example, a chain drive.

[0044] FIG. 3 shows a schematic view of a third exemplary embodiment of the transmission G which essentially corresponds to the second exemplary embodiment represented in FIG. 2. Only the arrangement of the electric machine EM and the arrangement of the fourth shift element D have been changed. The electric machine EM is also arranged axially parallel to the input shaft GW1, although in the rear area of the transmission G, which is axially opposite the interface GA. The connection of the electric machine EM to the input shaft GW1 takes place via a spur gear drive ST2. The fourth shift element D, which is designed as a form-fit brake, is arranged radially within the output shaft bearing GW2L in a space-saving manner in this case.

[0045] FIG. 4 shows a schematic view of a fourth exemplary embodiment of the transmission G which essentially corresponds to the third exemplary embodiment represented in FIG. 3. Only the arrangement of the electric machine EM has been changed, which is arranged coaxially to the input shaft GW1 in this case. Such an arrangement allows for a better mechanical efficiency of the transmission G, since the spur gear drive ST2 is dispensed with.

[0046] FIG. 5 shows a schematic view of a fifth exemplary embodiment of the transmission G which is distinguished by an arrangement of the transmission components which has been changed as compared to the preceding exemplary embodiments. The planetary gear set system PS is now arranged axially between the interface GA and the output-shaft tooth system GW2A. The electric machine EM is arranged coaxially to the input shaft GW1 and axially between the interface GA and the planetary gear set system PS. The output-shaft tooth system GW2A is arranged axially between the planetary gear set system PS and the bearing shield LS. The first shift element A and the fifth shift element E are arranged axially between the electric machine EM and the planetary gear set system PS. The fourth shift element D is arranged radially within the output shaft bearing GW2L. The bearing shield LS is arranged axially between the output-shaft tooth system GW2A and the second shift element B and the third shift element C.

[0047] FIG. 6 shows a schematic view of a sixth exemplary embodiment of the transmission G which essentially corresponds to the fifth exemplary embodiment represented in FIG. 5. The electric machine EM is arranged axially parallel to the input shaft GW1 in this case, and is operatively connected to the input shaft GW1 via a spur gear drive ST3. The spur gear drive ST3 is designed as a two-stage spur gear drive in this case. Elements of the spur gear drive ST3 are arranged together with the separating clutch KO in a shared plane.

[0048] FIG. 7 shows a schematic view of a seventh exemplary embodiment of the transmission, which is distinguished by a differently designed planetary gear set system PS2. The planetary gear set system PS2 includes a Ravigneaux gear set PR and an additional planetary gear set P23 which is designed as a plus gear set. A sun gear PR1 of the Ravigneaux gear set, which intermeshes with its outer planet gears, is designed to be integral with a ring gear E233 of the additional planetary gear set P23. The additional planetary gear set P23 is arranged radially within the sun gear PR1 in this case. By engaging the first shift element A, the input shaft GW1 is connected to a sun gear PR4 of the Ravigneaux gear set PR, which intermeshes with its radially inner planet gears. By engaging the second shift element B, a carrier E223 of the additional planetary gear set P23 is rotationally fixed. By engaging the third shift element C, the sun gear PR1 is rotationally fixed. By engaging the fourth shift element D, a common carrier PR2 of the Ravigneaux gear set PR is rotationally fixed. By engaging the fifth shift element E, the input shaft GW1 is connected to the carrier PR2. A ring gear PR3 of the Ravigneaux gear set PR is permanently connected to the output shaft GW2.

[0049] FIG. 8 shows a structural cutaway view of the second exemplary embodiment of the transmission G represented in FIG. 2. For greater clarity, two cutting planes of the transmission G are presented in FIG. 8 in one plane, namely a cutting plane through the axially parallel electric machine EM and a cutting plane through the planetary gear set system PS, the further elements of the transmission G arranged coaxially thereto, and one portion of the spur gear drive ST1. The two cutting planes are combined in the area of the spur gear drive ST1, whereby the spur gear drive ST1 appears to be non-rotationally symmetrical. Sections of the housing GG, the differential gear AG, and the intermediate shaft between the differential gear AG and the output shaft GW2 are not represented. The structural cutaway view makes it clear that, due to the utilization of the planetary gear set system PS according to the invention, a transmission G including an electric machine EM requires a particularly small amount of axial installation space.

[0050] FIG. 9 shows a shift pattern which can be applied for all exemplary embodiments of the transmission G. Six forward gears 1 through 6 and one reverse gear R1 are indicated in the rows of the shift pattern. In the columns of the shift pattern, an X indicates which of the shift elements A, B, C, D, E is engaged in which forward gear 1 through 6, and in the reverse gear R1. The gears 1 through 6 relate to fixed speed ratios between the input shaft GW1 and the output shaft GW2.

[0051] FIG. 10 shows an isolated representation of the planetary gear set system PS including its elements sun gear E11, carrier E21, and ring gear E31 of the first planetary gear set P1, sun gear E12, carrier E22, and ring gear E32 of the second planetary gear set P2, as well as sun gear E13 and carrier E23 of the third planetary gear set P3. The third planetary gear set P3 is designed as a plus gear set in this case, merely by way of example.

[0052] FIG. 11 shows an isolated representation of the planetary gear set system PS2 including its elements sun gear PR1, sun gear PR2, carrier PR30 and ring gear PR4 of the Ravigneaux gear set PR, as well as sun gear E213, carrier E223, and ring gear E233 of the additional planetary gear set P23.

[0053] 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

[0054] PS planetary gear set system [0055] P1 first planetary gear set [0056] E11 sun gear of the first planetary gear set [0057] E21 carrier of the first planetary gear set [0058] E31 ring gear of the first planetary gear set [0059] P2 second planetary gear set [0060] E12 sun gear of the second planetary gear set [0061] E22 carrier of the second planetary gear set [0062] E32 ring gear of the second planetary gear set [0063] P3 third planetary gear set [0064] E13 sun gear of the third planetary gear set [0065] E23 carrier of the third planetary gear set [0066] PS2 planetary gear set system [0067] PR Ravigneaux gear set [0068] PR1 sun gear of the Ravigneaux gear set [0069] PR2 carrier of the Ravigneaux gear set [0070] PR3 ring gear of the Ravigneaux gear set [0071] PR4 sun gear of the Ravigneaux gear set [0072] P23 additional planetary gear set [0073] E213 sun gear of the additional planetary gear set [0074] E223 carrier of the additional planetary gear set [0075] E233 ring gear of the additional planetary gear set [0076] G transmission [0077] GW1 input shaft [0078] GW2 output shaft [0079] GW2A output-shaft tooth system [0080] GW2L antifriction bearing [0081] GA interface [0082] GG transmission housing [0083] LS bearing shield [0084] EM electric machine [0085] S stator [0086] R rotor [0087] AG differential gear [0088] DW driving wheel [0089] KO separating clutch [0090] TS torsional vibration damper [0091] A first shift element [0092] B second shift element [0093] C third shift element [0094] D fourth shift element [0095] E fifth shift element [0096] ST1 spur gear drive [0097] ST2 spur gear drive [0098] ST3 spur gear drive [0099] 1 first forward gear [0100] 2 second forward gear [0101] 3 third forward gear [0102] 4 fourth forward gear [0103] 5 fifth forward gear [0104] 6 sixth forward gear [0105] R1 reverse gear