Multi-speed transmission

Abstract

An eight gear transmission having drive and output shafts, planetary gearsets, shafts and shifting elements. One carrier of the gearset (RS4) and the drive shaft are coupled to form shaft (1). One ring gear of the gearset (RS2), one carrier of the gearset (RS3) and the output shaft are coupled to form shaft (2). One sun gear of the gearset (RS1) and one sun gear of the gearset (RS4) are coupled to form shaft (3). One carrier of the gearset (RS1) forms shaft (4). One sun gear of the gearset (RS3) forms the fifth shaft. One ring gear of the gearset (RS1) and one carrier of the gearset (RS2) and one ring gear of the gearset (RS3) are coupled to form shaft (6). One ring gear of the gearset (RS4) forms the seventh shaft. One sun gear of the gearset (RS2) forms shaft (8).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example, with reference to the accompanying drawings in which:

FIG. 1 is a schematic view of an exemplary embodiment for a multi-speed transmission according to the present invention;

FIG. 2 is an exemplary shifting diagram for the multi-speed transmission according to FIG. 1.

Claims

1-33. (canceled)

34. A multi-speed automatic transmission of a planetary design for a motor vehicle, the transmission comprising: a drive shaft (AN) and an output shaft (AB);first, second, third, and fourth planetary gearsets (RS1, RS2, RS3, RS4), and each of the first, the second, the third, and the fourth planetary gearsets (RS1, RS2, RS3, RS4) comprises a sun gear, a carrier and a ring gear;at least first, second, third, fourth, fifth, sixth, seventh, and eighth rotatable shafts (1, 2, 3, 4, 5, 6, 7, 8) and first, second, third, fourth and fifth shifting elements (A, B, C, D, E) whose selective engagement creates different gear ratios between the drive shaft (AN) and the output shaft (AB) so that eight forward gears and a reverse gear can be implemented;wherein the carrier (ST4) of the fourth planetary gearset (RS4) and the drive shaft (AN are coupled with one another and form the first shaft (1);the sun gear (SO1) of the first planetary gearset (RS1) and the sun gear (SO4) of the fourth planetary gearset (RS4) are coupled with one another and form the third shaft (3);the ring gear (HO2) of the second planetary gearset (RS2), the carrier (ST3) of the third planetary gearset (RS3) and the output shaft (AB) are coupled with one another and form the second shaft (2);the carrier (ST1) of the first planetary gearset (RS1) forms the fourth shaft (4);the sun gear (SO3) of the third planetary gear shaft (RS3) forms the fifth shaft (5);the ring gear (HO1) of the first planetary gearset (RS1), the carrier (ST2) of the second planetary gearset (RS2) and the ring gear (HO3) of the third planetary gearset (RS3) are coupled with one another and form the sixth shaft (6);the ring gear (HO4) of the fourth planetary gearset (RS4) forms the seventh shaft (7);the sun gear (SO2) of the second planetary gearset (RS2) forms the eighth shaft (8);the first shifting element (A) is located between the third shaft (3) and a gearbox housing (GG);the second shifting element (B) is located between the fourth shaft (4) and the gearbox housing (GG);the third shifting element (C) is located, in a direction of power flow, between the first shaft (1) and the fifth shaft (5);the fourth shifting element (D) is located, in the direction of power flow, between the seventh (7) shaft and the eighth shaft (8); andthe fifth shifting element (E) is located, in the direction of power flow, between the fifth shaft (5) and the seventh shaft (7).

35. The multi-speed transmission according to claim 34, wherein a first forward gear is achieved by engagement of the first, the second and the third shifting elements (A, B, C);a second forward gear is achieved by engagement of the first, the second and the fifth shifting elements (A, B, E);a third forward gear is achieved by engagement of the second, the third and the fifth shifting elements (B, C, E);a fourth forward gear is achieved by engagement of the second, the fourth and the fifth shifting elements (B, D, E);a fifth forward gear is achieved by engagement of the second, the third and the fourth shifting element (B, C, D);a sixth forward gear is achieved by engagement of the third, the fourth and the fifth shifting elements (C, D, E);a seventh forward gear is achieved by engagement of the first, the third and the fourth shifting elements (A, C, D);an eighth forward gear is achieved by engagement of the first, the fourth and the fifth shifting elements (A, D, E); andthe reverse gear is achieved by engagement of the first, the second and the fourth shifting elements (A, B, D).

36. The multi-speed transmission according to claim 34, wherein the second, the third and the fourth planetary gearsets (RS2, RS3, RS4) are negative planetary gearsets and the first planetary gearset (RS1) is a positive planetary gearset.

37. The multi-speed transmission according to claim 34, wherein the first, the second, the third and the fourth planetary gearsets (RS1, RS2, RS3, RS4) are co-axially arranged, in the direction of power flow, in the following sequential order: the first planetary gearset (RS1), the fourth planetary gearset (RS4), the second planetary gearset (RS2) and the third planetary gearset (RS3).

38. The multi-speed transmission according to claim 34, wherein the drive shaft (AN) is one of parallel to and at an angle to the output shaft (AB), and one of the first and the third planetary gearsets (RS1, RS3) functionally communicates with the drive shaft (AN) and is located on a side of the gearbox housing (GG) adjacent a drive motor.

39. The multi-speed transmission according to claim 34, wherein the drive shaft (AN) is co-axial with the output shaft (AB), and the first planetary gearset (RS1) functionally communicates with the drive shaft (AN) and is located on a side of the gearbox housing (GG) adjacent a drive motor.

40. The multi-speed transmission according to claim 34, wherein a singe one of the first, the second, the third, the fourth, the fifth, the sixth, the seventh, and the eighth shafts (1, 2, 3, 4, 5, 6, 7, 8) is located within and coaxial to each of the first, the second, the third and the fourth planetary gearsets (RS1, RS2, RS3, RS4).

41. The multi-speed transmission according to claim 34, wherein the first shaft (1) is located within and coaxial to both the first and the fourth planetary gearsets (RS1, RS4), and the fifth shaft (5) is located within and coaxial to the second planetary gearset (RS2).

42. The multi-speed transmission according to claim 34, wherein none of the first, the second, the third, the fourth, the fifth, the sixth, the seventh, and the eighth shafts (1, 2, 3, 4, 5, 6, 7, 8) is located within and coaxial with either the first planetary gearset (RS1) and the fourth planetary gearset (RS4); the fifth shaft (5) and the first shaft (1) are located within and coaxial with the second planetary gearset (RS2), the first shaft (1) is coaxial with and located, at least partially, within the fifth shaft (5), and only the first shaft (1) is located within and coaxial with the third planetary gearset (RS3).

43. The multi-speed transmission according to claim 34, wherein the third shaft (3) detachably communicates with a hub fixed to the gearbox housing (GG).

44. The multi-speed transmission according to claim 34, wherein at least one of the first shifting element (A) and the second shifting element (B), when viewed radially, is at least partially located about one of the first planetary gearset (RS1) and the fourth planetary gearset (RS4).

45. The multi-speed transmission according to claim 34, wherein the first shifting element (A), when viewed in the direction of power flow, is axially adjacent the second shifting element (B), and at least one friction element of the second shifting element (B), when viewed in the direction of power flow, is located closer to the fourth planetary gearset (RS4) than the first shifting element (A).

46. The multi-speed transmission according to claim 34, wherein the first shifting element (A) and the second shifting element (B), when viewed radially, are located at least partially one above the other.

47. The multi-speed transmission according to claim 34, wherein the third shifting element (C), when viewed in the direction of power flow, is at least partially located between the fourth planetary gearset (RS4) and the second planetary gearset (RS2).

48. The multi-speed transmission according to claim 34, wherein the third shifting element (C) is axially adjacent the fourth planetary gearset (RS4).

49. The multi-speed transmission according to claim 34, wherein the fourth shifting element (D), when viewed in the direction of power flow, is at least partially located between the fourth planetary gearset (RS4) and the second planetary gearset (RS2).

50. The multi-speed transmission according to claim 34, wherein a disk pack of the fourth shifting element (D) is located axially adjacent the second planetary gearset (RS2).

51. The multi-speed transmission according to claim 34, wherein the fifth shifting element (E), when viewed in the direction of power flow, is at least partially located between the fourth planetary gearset (RS4) and the second planetary gearset (RS2).

52. The multi-speed transmission according to claim 34, wherein the fifth shifting element (E), when viewed in the direction of power flow, is at least partially located between the third shifting element (C) and the fourth shifting element (D).

53. The multi-speed transmission according to claim 34, wherein a disk pack of the fifth shifting element (E), when viewed radially, is at least partially located about a disk pack of the third shifting element (C).

54. The multi-speed transmission according to claim 34, wherein the fourth shifting element (D) and the fifth shifting element (E) have a common disk carrier, which is coupled to the ring gear (HO4) of the fourth planetary gearset (RS4).

55. The multi-speed transmission according to claim 34, wherein the third shifting element (C) and the fifth shifting element (E) have a common disk carrier which is coupled to the sun gear (SO3) of the third planetary gearset (RS3).

56. The multi-speed transmission according to claim 34, wherein the fourth planetary gearset (RS4), the second planetary gearset (RS2), and the third, the fourth and the fifth shifting elements (C, D, E) are completely contained within an axial length of the sixth shaft (6).

57. The multi-speed transmission according to claim 34, wherein a one-way clutch is located between at least one of the drive shaft (AN), the output shaft (AB), the first shaft (1), the second shaft (2), the third shaft (3), the fourth shaft (4), the fifth shaft (5), the sixth shaft (6), the seventh shaft (7), and the eighth shaft (8) and the gearbox housing (GG).

58. The multi-speed transmission according to claim 34, wherein the drive shaft (AN) and the output shaft (AB) are located on opposite sides of the gearbox housing (GG).

59. The multi-speed transmission according to claim 34, wherein the drive shaft (AN) and the output shaft (AB) are located on a common side of the gearbox housing (GG).

60. The multi-speed transmission according to claim 34, wherein at least one of a differential and transfer differential is located on one of the drive shaft (AN) and the output shaft (AB).

61. The multi-speed transmission according to claim 34, wherein a coupling element is located, in the direction of power flow, between a drive motor and the drive shaft (AN).

62. The multi-speed transmission according to claim 61, wherein the coupling element is one of a hydrodynamic converter, a hydraulic clutch, a dry start clutch, a wet start clutch, a magnetic powder clutch and a centrifugal clutch.

63. The multi-speed transmission according to claim 34, wherein a driving element communicates with at least one of the first shifting element (A), the second shifting element (B), the third shifting element (C) and the fourth shifting element (D), and the drive shaft (AN) is fixed to a crankshaft of a drive motor.

64. The multi-speed transmission according to claim 63, wherein engagement of one of the first shifting element (A) and the second shifting element (B) initiates both forward movement and reverse movement of the vehicle.

65. The multi-speed transmission according to claim 34, wherein one of a wear free brake and an accessory drive is located on at least one of the drive shaft (AN), the output shaft (AB), the first shaft (1), the second shaft (2), the third shaft (3), the fourth shaft (4), the fifth shaft (5), the sixth shaft (6), the seventh shaft (7), and the eighth shaft (8) to drive at least one of an additional unit and an electrical machine.

66. The multi-speed transmission according to claim 34, wherein each of the first, the second, the third, the fourth and the fifth shifting elements (A, B, C, D, E) are one of an interlocking clutch, an interlocking brake, a disk clutch, a band brake, a cone clutch, a positive locking clutch, a positive locking brake and a claw clutch.