Electric all-wheel drive with two speeds and split double reduction planetary gearbox

Abstract

Product comprising: an electric machine (86) operatively connected to a drive train module (10) comprising a gear train (36) with a fixed gear ratio, a first planetary gear set (48) with multiple gear ratios connected to the gear train (36), a second planetary gear set (74) with a fixed gear ratio operatively connected to the first planetary gear set (48), and a synchronizer (70), wherein the synchronizer (70) is operatively connected to the first planetary gear set (48) and is positioned between the first planetary gear set (48) and the second planetary gear set (74); a differential (12) operatively connected to the second planetary gear set (74);wherein the electric machine (86) selectively transmits power to the differential (12) through the transmission train (36), the first planetary gear set (48), the synchronizer (70), and the second planetary gear set (74), and wherein the synchronizer (70) is designed and arranged to switch the drive train module (10) into a high-range mode, a low-range mode, and a neutral mode by shifting a ring gear (62) of the first planetary gear set (48).

Description

TECHNICAL AREA

[0001] The area to which the revelation generally refers includes vehicle powertrains. BACKGROUND

[0002] A vehicle powertrain can include at least one drive train that can propel the vehicle. SUMMARY OF EXAMPLE EXECUTION FORMS

[0003] A number of variations may include: an electric machine operatively connected to a drive train module comprising a fixed-ratio gear train, a first multi-ratio planetary gear set connected to the gear train, a second fixed-ratio planetary gear set operatively connected to the first planetary gear set, and a synchronizer, wherein the synchronizer is operatively connected to the first planetary gear set and positioned between the first and second planetary gear sets; a differential operatively connected to the second planetary gear set;wherein the electric machine selectively transmits power to the differential through the transmission train, the first planetary gear set, a synchronizer, and the second planetary gear set, and wherein the synchronizer is designed and arranged to switch the drive train module into a high-range mode, a low-range mode, and a neutral mode by placing a ring gear of the first planetary gear set.

[0004] A number of variations may include a product comprising an electric machine operatively connected to a drivetrain module, wherein the drivetrain module comprises an axle assembly with a central support shaft, a helical gear transmission, a first helical planetary gear set operatively connected to the helical gear transmission, a synchronizer operatively connected to the first helical planetary gear set, and a second helical planetary gear set adjacent to the synchronizer and operatively connected to the first helical planetary gear set and the axle assembly; and wherein the synchronizer is designed and arranged to displace a first ring gear of the first helical planetary gear set in order to switch the drivetrain module into a high-range mode, a neutral mode, and a low-range mode.

[0005] A number of variations may include a method for driving an axle differential, comprising the following steps: selectively driving an electric machine having a rotatable shaft; driving a helical gear unit operatively connected to the rotatable shaft using the electric machine; providing an output from the helical gear unit to a first helical planetary gear set comprising a sun gear, at least two planet gears, a ring gear, and a carrier; moving the ring gear into a first position to fix the ring gear to a housing to achieve a low-range mode, using synchronization; or moving the ring gear into a second position connecting the ring gear to the carrier by a central carrier shaft to achieve a high-range mode, using synchronization.Driving a second helical planetary gear set with output from the first planetary gear set and the synchronizer; and driving the differential with output from the second helical planetary gear set.

[0006] Further embodiments for illustrative purposes, which fall within the scope of the invention, will become clear from the detailed description given below. It should be clear that the detailed description and the specific examples, even if they disclose variations within the scope of the invention, serve purely for illustrative purposes and are not intended to limit the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Selected examples of variations within the scope of the invention will become clear from the detailed description and the accompanying drawings, in which: Fig. Figure 1 illustrates a cross-section of a powertrain module after a series of variations. DETAILED DESCRIPTION OF EXAMPLES OF EXECUTION

[0008] The following description of variations is purely for illustrative purposes and is in no way intended to limit the scope of the invention, its application or its possible uses.

[0009] In a number of variations, a vehicle can include a powertrain module 10 that can transmit power to a differential 12. Referring to Fig. 1. A drivetrain module 10 can transmit power in a number of variations through a gear train 36, a first planetary gear set 48, a synchronizer 70, and a second planetary gear set 74 up to the differential 12. In a number of variations, the gear train 36 can provide a fixed gear ratio, while the first planetary gear set 48 can provide several gear ratios, so that the drivetrain module 10 can provide a low range, a neutral range, and a high range between an electric machine 86 and an axle assembly 94. In a number of variations, power can be transmitted through the drivetrain module 10 so that the electric machine 86 drives the axle assembly 94, for example, for propulsion. Power can also be transmitted through the drivetrain module 10 so that the axle assembly 94 drives the electric machine 86, for example, for regenerative braking.

[0010] In a number of variations, an axle assembly 94 can extend through the drivetrain module 10 and can be effectively attached to a first wheel 110 and a second wheel 112. Any number of axle assembly configurations can be used, including, but not limited to, axle assemblies with constant velocity joints and other common components known to those skilled in the art. In a number of variations, an axle assembly 94 can comprise a first axle shaft 96, a central support shaft 97, which can be concentric with the first axle shaft 96 and can surround a section of the first axle shaft 96, a second axle shaft 104, and a differential 12. The central support shaft 97 can be hollow and can comprise a first end 98 and a second end 100. In a number of variations, the first end 98 can be supported in a first bearing 102.In a number of variations, the second axle shaft 104 can be hollow and can include a first end 106 and a second end 108.

[0011] In several variations, a differential 12 can be effectively mounted on the first and second axle shafts 96, 104 and can comprise a cage 14 and a pinion shaft 16, which can extend between a first end 18 of the cage 14 and a second end 20 of the cage 14. In several variations, a first drive gear 22 and a second drive gear 24 can be rotatably mounted on the pinion shaft 16. A first lateral gear 26 can mesh with the first drive gear 22, and a second lateral gear 28 can mesh with the second drive gear 24. In several variations, the cage 14 can be supported by a first and second bearing 30, 32 and can be rotatable. In several variations, the second planetary gear set 74 can be positioned inside the cage 14.A first side 34 of the cage 14 can be connected to or be integral with a carrier 82 of the second planetary gear set 74, and can rotate with the carrier 82.

[0012] In a number of variations, the cage 14 can be rotated, which can cause the first and second drive gears 22, 24 and the first and second lateral gears 26, 28 to rotate, which in turn can cause the first axle shaft 96 and the second axle shaft 104 to rotate the first and second gears 110, 112, respectively. In a number of variations, an input can be provided from the first gear 110 and the second gear 112, for example for regenerative braking, which can cause the first and second axle shafts 96, 104 to rotate the first and second lateral gears 26, 28, which in turn can cause the first and second drive gears 22, 24 to rotate, which then can rotate the cage 14.

[0013] In a number of variations, an electric machine 86 can be operatively connected to the drivetrain module 10 and can supply power to the axle assembly 94 via the drivetrain module 10 and the differential 12. Any number of electric machines 86 can be used, which may, but are not limited to, include a motor, a motor-generator, or another type of electric machine. In a number of variations, a shaft 88, which may, but are not limited to, include a rotor shaft, can extend from the electric machine 86 and can be supported by first and second bearings 90, 92. In a number of variations, a housing 44 can surround at least a section of the electric machine 86, the drivetrain module 10, and the differential 12. The housing 44 can comprise a single continuous component or two or more separate components.In a number of variations, the housing 44 can be constructed and arranged to contain a lubricant, which may include oil but is not limited to it.

[0014] In several variations, the shaft 88 of the electric machine 86 can be operatively connected to the gear train 36. In several variations, the gear train 36 can include helical gears. The gear train 36 can be used to provide an input to and an output from the electric machine 86. In several variations, the gear train 36 can include a first gear 38, which can be operatively attached to the shaft 88 and rotate with the shaft 88. The first gear 38 can mesh with and rotate with a second gear 40. The second gear 40 can have a larger diameter than the first gear 38, which can provide a reduction gear between the two gears from the shaft 88. The second gear 40 can mesh with and rotate with a third gear 42.In a number of variations, the second gear 40 can be an intermediate gear that can engage between the first gear 38 and the third gear 42, and can rotate about a center that lies behind the plane of view of . Fig. The gears can be offset by 1. This can allow shaft 88 to be positioned close to the first axle shaft 96, which can minimize the space between the first and third gears 38, 42, thus reducing the packing space. In a number of variations, the use of a helical gear drive can allow for easy lubrication at high speeds, since the gears 38, 40, 42 can be larger and more open than other gear types.

[0015] In a number of variations, the first, second, and third gears 38, 40, 42 can rotate about parallel axes. In a number of variations, the electric machine 86 can drive the gear train 36 such that the first gear 38 can be an input gear, the second gear 40 an intermediate gear, and the third gear 42 an output gear. In a number of variations, the electric machine 86 can be arranged by the axle arrangement 94 such that the third gear 42 can then be an input gear, the second gear 40 the intermediate gear, and the first gear 38 the output gear.

[0016] In several variations, the third gear 42 can be operatively connected to a sun gear 52 of the first planetary gear set 48. The third gear 42 and the sun gear 52 can be operatively mounted to one another, so that the third gear 42 and the sun gear 52 can rotate together. In several variations, the sun gear 52 can rotate freely on the central support shaft 97. In several variations, the sun gear 52 can be rotatably connected to a first planet gear 54 and a second planet gear 56 such that the first planet gear 54 and the second planet gear 56 can rotate with the sun gear 52. The first planet gear 54 can rotate on a first pivot 58, which may be fixed to a support 50, and the second planet gear 56 can rotate on a second pivot 60, which may also be fixed to the support 50.It should be noted that, depending on the design requirements, more than two planet gears may be used. The first planet gear 54 and the second planet gear 56 can mesh with and rotate with a ring or hollow gear 62, which may include internal teeth. In several variations, the hollow gear 62 may also include a hub 64, which may comprise a first section 66 extending radially to the central support shaft 97, and a second section 68 extending axially from the end 67 of the first section 66. In several variations, the hollow gear hub 64 may be designed and arranged to mesh with the synchronizer 70, as will be explained below. The first planet gear set 48 may comprise any number of gear types, which may, but are not limited to, include helical gears.In a number of variations, the sun gear 52 can be rotated, which can cause the first and second planet gears 54, 56 to rotate inside the ring gear 62, which can cause the carrier 50 to rotate.

[0017] Any number of synchronizers 70 can be used in the drivetrain module 10, which may allow switching of the drivetrain module 10. In a number of variations, the synchronizer 70 may include a synchronizing hub 72. The synchronizing hub 72 may be designed and arranged to engage with the ring gear hub 64 of the first planetary gear set 48 such that the synchronizing hub 72 can move the ring gear 64 axially with the synchronizing hub 72. In a number of variations, the range selection may be effected by an actuator (not illustrated) that can move the synchronizing hub 72 axially with respect to the central support shaft 97. The synchronizer 70 may selectively disconnect the differential 12 from the electric machine 86 to provide a neutral mode and may connect the electric machine 86 to the differential 12 to provide two operational power transmission modes.

[0018] In a number of variations, the synchronizing hub 72 can be selectively shifted to the left (in the perspective view of Fig. 1), which can cause the ring gear 62 of the first planetary gear set 48 to shift, so that the ring gear 62 can be locked to the housing 44, thus preventing it from rotating. When the ring gear 62 is locked, the rotational speed of the carrier 50 of the first planetary gear set 48 can be reduced and the torque increased, allowing the drivetrain module 10 to operate in a low-range operating mode. In a number of variations, the synchronizing hub 72 can be selectively shifted to the right (in the perspective view of Fig.1) which can cause the ring gear 62 of the first planetary gear set 48 to shift, so that the ring gear 62 can be operatively connected to the carrier 50 of the first planetary gear set 48, so that it can rotate with the carrier 50, which can be operatively connected to the central carrier shaft 97. When the ring gear 62 can be connected to the carrier 50 via the central carrier shaft 97, the rotational speed of the sun gear 52 can be maintained, so that the drive train module 10 can operate in a high-range operating mode.

[0019] In several variations, the output from the first planetary gear set 48 can be transmitted to the second planetary gear set 74, which can drive the differential 12. The second planetary gear set 74 can include a sun gear 76, first and second planet gears 78, 80, each of which can be mounted on a carrier 82 by a first and second journal 79, 81, and a ring gear 84, which may include internal teeth. It should be noted that, depending on the design requirements, more than two planet gears can also be used. In several variations, the ring gear 84 of the second planetary gear set 74 can be fixed to the housing 44 on an annularly extending wall 46, thus preventing it from rotating. The second planetary gear set 74 can be fixed to operate in a low-range mode.The second planetary gear set 74 can include any number of gear types, which, but are not limited to, may include helical gears.

[0020] In a number of variations, the synchronizing hub 72 can be actuated by any number of actuators known in the prior art, which may include, but are not limited to, electromechanical, electromagnetic, and / or hydraulic actuators. In a number of variations, the position of the synchronizer 70 between the first planetary gear set 48 and the second planetary gear set 74 can reduce the reflected inertia at the synchronizer 70.

[0021] In a number of variations, one or more features can be integrated into the drivetrain module 10 that can manage the sump level and reduce shear losses, as disclosed in US patent application number 14 / 824,724 (patent publication number US9410610B1), which is incorporated herein by reference.

[0022] In accordance with the variations described above, a vehicle can be equipped with an axle assembly 94, which can be driven by an electric machine 86, providing electric all-wheel drive. In several variations, the vehicle can be equipped with a second axle assembly, which can be driven by a conventional engine to achieve all-wheel drive. The first axle assembly 94 can drive the electric machine 86, enabling regenerative braking to charge the vehicle battery. In several variations, the first axle assembly 94 can be driven by the electric machine 86, improving traction and vehicle dynamics. The first axle assembly 94 can provide an electric drive with improved torque in a low-voltage system, which, but is not limited to, includes a 48-volt system.The first axle arrangement 94 can be arranged in any number of positions in a vehicle, which includes, but is not limited to, the rear axle in a front-wheel drive vehicle or the front axle in a rear-wheel drive vehicle.

[0023] The following description of exemplary embodiments serves solely to illustrate components, elements, actions, products, and processes that are considered to fall within the scope of the invention and is in no way intended to limit the scope by what is disclosed in detail or not expressly stated. The components, elements, actions, products, and processes described herein may be combined and rearranged in ways other than expressly described herein and will nevertheless be considered to fall within the scope of the invention.

[0024] Variation 1 may include a product comprising: an electric machine operatively connected to a drive train module comprising a fixed-ratio gear train, a first multi-ratio planetary gear set connected to the gear train, a second fixed-ratio planetary gear set operatively connected to the first planetary gear set, and a synchronizer, wherein the synchronizer is operatively connected to the first planetary gear set and positioned between the first and second planetary gear sets; a differential operatively connected to the second planetary gear set;wherein the electric machine selectively transmits power to the differential through the transmission train, the first planetary gear set, the synchronizer, and the second planetary gear set, and wherein the synchronizer is designed and arranged to switch the drive train module into a high-range mode, a low-range mode, and a neutral mode by placing a ring gear of the first planetary gear set.

[0025] Variation 2 may include a product according to Variation 1, wherein the synchronization further comprises a synchronizing hub, and wherein the synchronizing hub is effectively attached to the ring gear, and wherein the synchronization is designed and arranged to displace the synchronizing hub to move the ring gear into a first position to fix the ring gear to the drive train module to achieve the low-range mode, into a second position to effectively connect the ring gear to a carrier of the first planetary gear set to achieve the high-range mode, and into a third position in which the ring gear is not fixed and is not connected to the carrier of the first planetary gear set to achieve the neutral mode.

[0026] Variation 3 may include a product according to any of variations 1 to 2, wherein the gear train comprises a first gear operatively connected to the electric machine, a second gear operatively connected to the first gear, and a third gear operatively connected to the second gear and a sun gear of the first planetary gear set.

[0027] Variation 4 can include a product according to any of variations 1 to 3, wherein the gear train includes helical gears.

[0028] Variation 5 can include a product according to any of variations 1 to 4, wherein the first planetary gear set and the second planetary gear set comprise helical gears.

[0029] Variation 6 may include a product according to any of variations 1 to 5, wherein an axle shaft assembly extends through the transmission train, the first planetary gear set, the synchronizer, the second planetary gear set and the differential.

[0030] Variation 7 may include a product comprising an electric machine operatively connected to a drivetrain module, and an axle assembly with a central support shaft operatively connected to the drivetrain module, wherein the drivetrain module comprises a helical gear unit, a first helical planetary gear set operatively connected to the helical gear unit, a synchronizer operatively connected to the first helical planetary gear set, and a second helical planetary gear set adjacent to the synchronizer and operatively connected to the first helical planetary gear set and the axle assembly; and wherein the synchronizer is designed and arranged to displace a first ring gear of the first helical planetary gear set in order to switch the drivetrain module into a high-range mode, a neutral mode, and a low-range mode.

[0031] Variation 8 may include a product according to Variation 7, wherein the synchronization further comprises a synchronizing hub, and wherein in the high-range mode the synchronizing hub connects the ring gear of the first planetary gear set to a carrier of the first helical planetary gear set through the central carrier shaft, wherein in the low-range mode the synchronizing hub fixes the ring gear of the first helical planetary gear set to the drive module, and wherein in the neutral mode the synchronizing hub disconnects the electric machine from the axle assembly.

[0032] Variation 9 can be a product according to one of variations 7 and 8, wherein the axle arrangement further comprises a first axle shaft extending through the central support shaft, a second axle shaft, and a differential between the first axle shaft and the second axle shaft, and wherein the second helical planetary gear set is operatively connected to the differential.

[0033] Variation 10 may include a product according to any of Variations 7 to 9, further comprising a housing, wherein the housing encloses at least part of the electric machine, the drive train module, and the axle assembly. Variation 11 may include a product according to Variation 10, wherein the housing is designed and arranged to contain a lubricant.

[0034] Variation 12 may include a product according to any of variations 7 to 11, wherein the first helical planetary gear set comprises a sun gear, at least two planet gears rotatably mounted on a carrier and meshing with and being rotated by the sun gear, and a first ring gear, and wherein the at least two planet gears rotate within the first ring gear.

[0035] Variation 13 may include a product according to any of variations 7 to 12, wherein the second helical planetary gear set comprises a sun gear, at least two planet gears rotatably mounted on a carrier and meshing with and being rotated by the sun gear, and a second ring gear, and wherein the at least two planet gears rotate within the second ring gear.

[0036] Variation 14 may include a method for driving an axle differential comprising the following steps: selectively driving an electric machine having a rotatable shaft; driving a helical gear unit operatively connected to the rotatable shaft using the electric machine; providing an output from the helical gear unit to a first helical planetary gear set comprising a sun gear, at least two planet gears, a ring gear, and a carrier; moving the ring gear into a first position to fix the ring gear to a housing to achieve a low-range mode, using synchronization, or moving the ring gear into a second position connecting the ring gear to the carrier by a central carrier shaft to achieve a high-range mode, using synchronization;Driving a second helical planetary gear set with output from the first planetary gear set and the synchronizer; and driving the differential with output from the second helical planetary gear set.

[0037] Variation 15 may include a method according to Variation 14, which further includes moving the ring gear into a third position to disconnect the electric machine from the differential using synchronization.

[0038] The above description of selected embodiments within the scope of the invention is purely exemplary, and therefore modifications and variants thereof are not considered to be deviations from the spirit and scope of the invention.

Claims

[1] Product comprising: an electric machine (86) operatively connected to a drive train module (10) comprising a gear train (36) with a fixed gear ratio, a first planetary gear set (48) with multiple gear ratios connected to the gear train (36), a second planetary gear set (74) with a fixed gear ratio operatively connected to the first planetary gear set (48), and a synchronizer (70) wherein the synchronizer (70) is operatively connected to the first planetary gear set (48) and is positioned between the first planetary gear set (48) and the second planetary gear set (74); a differential (12) operatively connected to the second planetary gear set (74);wherein the electric machine (86) selectively transmits power to the differential (12) through the transmission train (36), the first planetary gear set (48), the synchronizer (70), and the second planetary gear set (74), and wherein the synchronizer (70) is designed and arranged to switch the drive train module (10) into a high-range mode, a low-range mode, and a neutral mode by shifting a ring gear (62) of the first planetary gear set (48). [2] Product according to claim 1, wherein the synchronizer (70) further comprises a synchronizing hub (72), and wherein the synchronizing hub (72) is effectively attached to the ring gear (62), and wherein the synchronizer (70) is designed and arranged to displace the synchronizing hub (72) to move the ring gear (62) into a first position to lock the ring gear (62) to the drive train module (10) to achieve the low-range mode, into a second position to effectively connect the ring gear (62) to a carrier (50) of the first planetary gear set (48) to achieve the high-range mode, and into a third position in which the ring gear (62) is not locked and is not connected to the carrier (50) of the first planetary gear set (48) to achieve the neutral mode. [3] Product according to claim 1, wherein the gear train (36) comprises a first gear (38) operatively connected to the electric machine (86), a second gear (40) operatively connected to the first gear (38), and a third gear (42) operatively connected to the second gear (40) and a sun gear (52) of the first planetary gear set (48). [4] Product according to claim 1, wherein the gear train (36) comprises helical gears. [5] Product according to claim 1, wherein the first planetary gear set (48) and the second planetary gear set (74) comprise helical gears. [6] Product according to claim 1 comprising an axle shaft arrangement with a first axle shaft (96) and a second axle shaft (104), wherein the axle shaft arrangement extends through the transmission train (36), the first planet gear set (48), the synchronizer (70), the second planet gear set (74) and the differential (12). [7] Product comprising an electric machine (86) operatively connected to a drive train module (10), the drive train module (10) comprising an axle assembly (94) with a central support shaft (97), a helical gear transmission (36), a first helical planetary gear set (48) operatively connected to the helical gear transmission (36), a synchronizer (70) operatively connected to the first helical planetary gear set (48), and a second helical planetary gear set (74) adjacent to the synchronizer (70) and operatively connected to the first helical planetary gear set (48) and the axle assembly (94); and wherein the synchronization (70) is designed and arranged to displace a first ring gear (62) of the first helical planetary gear set (48) to switch the drive train module (10) into a high-range mode, a neutral mode and a low-range mode. [8] Product according to claim 7, wherein the synchronization (70) further comprises a synchronizing hub (72), and wherein in the high-range mode the synchronizing hub (72) connects the ring gear (62) of the first planetary gear set (48) to a carrier (50) of the first helical planetary gear set (48) through the central support shaft (97), wherein in the low-range mode the synchronizing hub (72) fixes the ring gear (62) of the first helical planetary gear set (48) to the drive module (10), and wherein in the neutral mode the synchronizing hub (72) disconnects the electric machine (86) from the axle assembly (94). [9] Product according to claim 7, wherein the axle arrangement (94) further comprises a first axle shaft (96) extending through the central support shaft (97), a second axle shaft (104), and a differential (12) between the first axle shaft (96) and the second axle shaft (104), and wherein the second helical planetary gear set (74) is operatively connected to the differential (12). [10] Product according to claim 7, further comprising a housing (44) wherein the housing (44) surrounds at least a part of the electric machine (86), the drive train module (10) and the axle assembly (94). [11] Product according to claim 10, wherein the housing (44) is designed and arranged to contain a lubricant. [12] Product according to claim 7, wherein the first helical planetary gear set (48) comprises a sun gear (52), at least two planet gears (54, 56) rotatably mounted on a carrier (50) and engaged with and rotated by the sun gear (52), and a first ring gear (62), and wherein the at least two planet gears (54, 56) rotate within the first ring gear (62). [13] Product according to claim 7, wherein the second helical planetary gear set (74) comprises a sun gear (76), at least two planet gears (78, 80) rotatably mounted on a carrier (82) and engaged with and rotated by the sun gear (76), and a second ring gear (84), and wherein the at least two planet gears (78, 80) rotate within the second ring gear (84). [14] Method for driving an axle differential (12) comprising the following steps: - selective driving of an electric machine (86) which has a rotatable shaft (88); - Driving a helical gear transmission (36) which is operatively connected to the rotatable shaft (88) using the electric machine (86); - Providing an output from the helical gear drive (36) to a first helical planetary gear set (48) with a sun gear (52), at least two planet gears (54, 56), a ring gear (62), and a carrier (50); - Moving the ring gear (62) into a first position to fix the ring gear (62) to a housing (44) to achieve a low range mode, using a synchronizer (70), or moving the ring gear (62) into a second position, which connects the ring gear (62) to the carrier (50) by means of a central carrier shaft (97) to achieve a high range mode, using the synchronizer (70); - Driving a second helical planetary gear set (74) with output from the first planetary gear set (48) and the synchronizer (70); and - Driving the differential (12) with output from the second helical planetary gear set (74). [15] Method according to claim 14, further comprising moving the ring gear (62) into a third position to disconnect the electric machine (86) from the differential (12) using the synchronization (70).

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