Two speed nested differential planetary gearbox design

Abstract

An axle for a vehicle includes an axle housing, a shifting clutch, a differential assembly rotationally supported by the axle housing via a pair of bearings, a motor configured to provide power to a torque transmitting gearset, an input gear driven by the torque transmitting gearset, an input housing driven by the input gear surrounding and supported by the differential assembly, a sun gear driven by the input housing, and a planetary gearset driven by said sun gear. The shifting clutch is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

Description

TWO SPEED NESTED DIFFERENTIAL PLANETARY GEARBOX DESIGNCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 585,977, filed September 28, 2023, entitled “TWO SPEED NESTED DIFFERENTIAL PLANETARY GEARBOX DESIGN,” which is incorporated herein by reference in its entirety.FIELD

[0002] The present disclosure is generally related to a two-speed gear arrangement which includes an input gear, planetary carrier, differential gearset, and shifting clutch arrangement provided in a reduced axial packaging space. More specifically the differential gearset provides power distribution to a first and second output, and supports and is surrounded radially by a selectively engaged torque multiplying planetary gear arrangement. The shifting clutch system will connect a high-speed ratio between the input gear and the differential housing without ratio change in its first operating condition. In a second operating condition, the shifting clutch system will connect the planetary carrier and the differential housing resulting in a torque multiplication by the planetary gearset to be distributed to the differential assembly. Such a two-speed gear arrangement may be utilized in an electrically driven axle.BACKGROUND

[0003] This section provides background information related to the present disclosure which is not necessarily prior art.

[0004] Many vehicles are operating over a wide range of vehicle speeds and may be powered by internal combustion engines or electrical motors. Both propulsion types may benefit from providing a transmission or gearbox with more than one speed to allow operation of the power source to be within an optimal speed range. Specifically for electrically driven vehicles, a single speed transmission is often used due to electric motors producing a consistent amount of power across a large operating range. This eliminates the needs for a complex multi speed transmission as found in most internal combustion powered vehicles. Providing a second lower ratio for use in an electrically driven vehicle is beneficial as either the torque delivered to theground engaging wheels is increased over a given input torque or the size of the electric motor may be reduced while delivering the same performance. It is also beneficial to provide a second high speed ratio during operating modes where maximum power is not required, such as highway cruising to provide energy efficient operation. In either application, whether electrically or internal combustion engine powered, it is beneficial to provide solutions where an increased ratio is provided which may be selectable based on the operating condition of the vehicle. Within these transmissions a differential assembly is also often provided which distributes power to the left and right ground engaging wheels and allows these wheels to rotate at slightly different speeds as the vehicle turns. Current solutions package the differential assembly and the planetary axially adjacent to each other or on different axis. Such arrangements may be difficult to arrange in the vehicle if space is limited.

[0005] Therefore, it would be beneficial to develop a two-speed gear arrangement which includes a low ratio, high ratio and a differential assembly nested within the planetary in a compact and optimized arrangement.SUMMARY

[0006] The two-speed gear arrangement described in this disclosure will utilize the example for use in an electrically driven vehicle, although other propulsion methods could also use the disclosed arrangement. The electrically driven vehicle will include at least one electrically driven axle assembly with power delivered to a pair of ground engaging wheels. The electric motor will provide power to a first gearset which may in turn directly drive the two-speed gear arrangement. Other gear set arrangements, prior to providing power to the two-speed gear arrangement, may be provided to further increase ratio or change the center distance between the motor and the ground engaging wheels. The two-speed gear arrangement disclosed may include an input gear, a planetary carrier, a bevel differential, and a shifting clutch with actuation system provided in a reduced axial packaging space rotating about an axis. An input gear will receive the power provided by the first gearset of the electrically driven axle in this example. The differential gearset may provide power distribution to the pair of ground engaging wheels via a pair of axle shafts. The differential gearset may be surrounded radially and support a selectively engaged torque multiplying planetary gear arrangement. The shifting clutch may transmit power betweenthe input gear and the differential assembly without ratio change in its first high speed operating condition. In the second operating condition, the shifting clutch may connect the output of the planetary carrier to the differential housing resulting in a torque multiplication by the planetary gearset resulting in a low speed ratio operating mode. A third operating mode may provide a disconnect, which may result in no torque transfer between the input gear and the differential.

[0007] The two-speed nested gear arrangement arranges the planetary gearset radially surrounding the differential providing an axially compact concept. The differential housing will be supported by the axle housing via a pair of bearings. The input gear of the two-speed nested gear arrangement is directly coupled to a bell-shaped housing portion which will be radially supported by the differential housing. This bell-shaped input housing may include an integrally formed gear form which functions as the sun gear for the planetary gear arrangement, engaging the planets of the planetary. The input housing and the sun gear will be coupled to the planetary via the gear mesh during all operational conditions, but selectively engaged to the differential gearset depending on the operating condition. The shifting clutch will provide a first connection between the input housing and the differential gearset resulting in operation without multiplication by the planetary. When the shifting clutch is operated in its second operating condition via a controllable actuator, engagement occurs between the carrier of the planetary and the differential housing, transmitting the increased torque created by the planetary to the ground engaging wheels via the differential assembly.

[0008] It is an aspect of the present disclosure to provide a two-speed electrically driven axle with a nested gearset arrangement where the planetary gearset is surrounding the differential assembly.

[0009] It is an aspect of the present disclosure to provide an axially compact gearset arrangement with a differential assembly where the planetary gearset is surrounding the differential assembly and provides a torque multiplying ratio.

[0010] It is a related aspect of the present disclosure to support the input housing radially via the differential housing with bearings to allow relative differential rotation in between.

[0011] It is a related aspect of the present disclosure to integrate an input gear and sun gear as part of a bell shaped input housing supported by the differential housing.

[0012] It is a related aspect of the present disclosure to align the planetary relative to the differential housing where the center of the differential housing corresponds to generally the center of the planetary gearset.

[0013] It is a related aspect of the present disclosure to provide a shifting clutch which in a first operational condition will connect the input housing to the differential housing to transmit power thru the gearset arrangement without ratio multiplication.

[0014] It is a related aspect of the present disclosure to provide a shifting clutch which in a second operational condition will connect the carrier of the planetary to the differential housing to transmit power thru the gearset arrangement with a ratio multiplication provided by the planetary.

[0015] It is a related aspect of the present disclosure to provide a shifting clutch which may be an axially moveable shift collar, a pair of frictionally engaging clutches, or a frictional clutch and a positive locking dog clutch.

[0016] It is a related aspect of the present disclosure to provide a third operating position where no connection is made between the differential assembly and the planetary or input housing to provide a disconnect between the ground engaging wheels and the input gear.

[0017] These and other features and advantages of the present disclosure will become more readily appreciated when considered in connection with the following detailed description and appending drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are for illustrative purposes only of selected embodiments and are not intended to limit the scope of the present disclosure. The inventive concepts associated with the present disclosure will be more readily understood by reference to the following description in combination with the accompanying drawings, in which:

[0019] FIG. 1 provides an example of a two-speed electrically driven axle using the nested planetary and differential gear arrangement;

[0020] FIG. 2 provides a first embodiment of the two-speed nested planetary and differential gear arrangement;

[0021] FIG. 3 provides the two-speed nested planetary and differential gear arrangement of the first embodiment in a high speed ratio operating mode;

[0022] FIG. 4 provides the two-speed nested planetary and differential gear arrangement of the first embodiment in a low speed ratio operating mode; and

[0023] FIG. 5 provides an alternative embodiment of the two-speed nested planetary and differential gear arrangement utilizing a pair of frictional clutches;DETAILED DESCRIPTION

[0024] Embodiments will now be described more fully with reference to the accompanying drawings. It is to be recognized the embodiments described herein only are provided so that this disclosure will be thorough, and will fully convey the scope, which is ultimately defined by the claims, to those who are skilled in the art. Numerous specific details are set forth, such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that certain specific details need not be employed, that example embodiments may be embodied in many different forms, and that neither should be construed to limit the scope of the disclosure or the claims. In some example embodiments, well-understood processes, well-understood device structures, and well-understood technologies are not described in detail. It will be further appreciated that reference made to particular aspects being optional does not imply that other aspects are not also optional in the absence of such a designation. It will be further appreciated that reference made to particular aspects being preferred does not imply that other aspects are not also preferred in the absence of such a designation.

[0025] FIG. 1 provides a two-speed electrically driven axle 10 with a nested gearset arrangement 12 where the planetary gearset 14 is surrounding the differential assembly 16. Theelectrically driven axle 10 will be powered by an electric motor 18. Electric motor 18 will provide power to a first gearset 20. First gearset 20 includes a driving gear 22 and a driven gear 24. Driving gear 22 will be connected via the rotor output shaft 26 to electric motor 18. Driven gear 24, which may also be the input gear to the nested gear arrangement 12, will be rotatably coupled to drive gear 22. The arrangement shown is the simplified form of first gearset 20. Other alternatives including additional gearset stages and gear arrangements which will transmit power with and without torque multiplication from the electric motor 18 to the input gear 24 may be utilized. The power provided to input gear 24 of nested gear arrangement 12 will be transmitted either directly to differential assembly 16 for operation in a high range or transmitted thru the torque multiplying planetary 14 and differential assembly 16 for operation in a low range. This will be dependent on the operational condition of the shifting clutch 28. Shifting clutch 28 will be operated by actuator 30. Shifting clutch 28 may be a be a positive engaging clutch engaged by an axially moveable shift collar with positive locking clutch elements, a pair of frictionally engaging clutches allowing controlled engagement over time, or a combination of a frictional clutch and a positive engaging clutch. Actuator 30 may be electro-magnetic, electromechanical, or hydraulic to provide actuation of shifting clutch 28. Actuator 30 may be directed by a control unit to control the engagement and disengagement characteristics of shifting clutch 28. Differential assembly 16 will distribute power thru a differential gearset 32 which will distribute power equally to a left ground engaging wheel 34A and a right ground engaging wheel 34B via axle shafts 36A and 36B. Further details of the components within nested gear arrangement 12 and its functionality will be provided in further figures. A first embodiment where shifting clutch 28 utilizes a shifting collar with positive engaging clutches and a second embodiment utilizing two frictionally engaging clutches will also be described.

[0026] FIG. 2 provides the first embodiment of the two-speed nested gear arrangement 12 utilizing an axially moving shift collar 40 as the shifting clutch 28 is shown. The nested gear arrangement 12 includes a differential assembly 16. Differential assembly 16 may be any suitable type of bevel gear differential designed to receive power into differential housing 42 and distribute the differential output torque to the axle shafts 36A and 36B. How power is provided to differential housing 42 in the various operating modes will be described in further detail later in the disclosure. In the example provided, the differential assembly 16 is an open differential but may also be a limited slip or locking differential. Differential assembly 16 includes a differential housing 42,differential gearset 32 and a cross-pin 44. Power will be transmitted from differential housing 42 thru cross pin 44 and into differential gearset 32. Differential housing 42 may be a single piece design or a two-piece design as shown in this disclosure, both which may encapsulate a pair of side gears 46 and pinion gears 48 in a cavity 50. The pair of differential pinions 48 are rotatably mounted on an axis perpendicular to the rotational axis of side gears 46. Differential pinions 48 will rotate about a cross pin 44 having its opposite ends secured in apertures 52 formed in differential housing 42. The pair of differential side gears 46 are each meshed with both differential pinions 48. Alternatively, a second pair of pinion gears 48 may be utilized for higher torque transferring capability. As is otherwise conventional, each differential side gear 46 has internal splines 54 configured to mesh with external splines formed on axle shafts 36A and 36B. Axle shafts 36A and 36B transmit output torque of differential gearset 32 to ground engaging wheels 34A and 34B. Differential assembly 16 is rotatably supported by a pair of differential support bearings 56 within the axle housing which is not shown.

[0027] As differential housing 42 is supported and located to rotate about an axis by bearings 56, it may be used to further support input gear 24 and input housing 58 which will be positioned to rotate concentrically about differential assembly 16. A bell-shaped input housing 58 will surround and be supported directly by differential housing 42. Input housing 58 will include a first open end 60 and a closed second end 62. On the closed second end 62 of input housing 58, an axially extending portion 64 will include a plurality of clutch teeth 66 on the outer diameter which will engage to shift collar 40. Differential assembly 16 will be received by the first open end 60 of input housing 58. Differential housing 42 will include a cylindrically shaped outer diameter 68 which will provide a journal surface for input housing support bearing 70. Input housing support bearing 70 may be a plurality of caged needle bearings, bushings or any other solution which will provide relative rotation and radial positional support between input housing 58 and differential housing 42. Input housing 58 axial position will be controlled relative to differential assembly 24 in the following manner. To prevent input housing 58 from moving to the left closer to differential housing 42 an axial thrust bearing 72 is positioned between the vertical outer surface 74 of differential housing 42 and the vertical wall 76 forming the closed end 62 of input housing 58. To prevent input housing 48 from moving towards the right, separating away from differential housing 42, a snap ring 78 is provided fixed to the extended portion 80 of differential housing 42 to the right of extending portion 64 of input housing 48. Snap ring 78 mayalso include a thrust washer or surface allowing relative motion with minimal friction between the differential housing 42 and input housing 58.

[0028] Continuing to refer to FIG. 2, input gear 24 will be coupled to the outer diameter 82 of input housing 58 towards the first open end 60. Input gear 24 may be integrated into input housing 58 or provided as a separate component splined, welded, or otherwise fixed to couple input gear 24 to input housing 58. Input housing 58 will include two power paths from input gear 24 dependent on the operational condition of shift collar 40. The first power path will be provided to planetary gearset 14 which will be positioned to radially surrounding the input housing 58. Planetary gearset 14 is a simple planetary arrangement shown to include a sun gear 84, a ring gear 86 fixed to axle housing not shown, and a set of planet gears 88 meshed with sun gear 84 and ring gear 86. Each planet gear 88 is rotatably supported on a pinion shaft 90. Each pinion shaft 90 extends between a front carrier ring 92 and a rear carrier ring 94 which are interconnected to define a planet carrier 96. Sun gear 84 is shown to be an integrated part of an input housing 58 in this example. Alternatively, sun gear 84 may be a separate piece but fixed (i.e., splined or welded) for common rotation with input housing 58. As such, rotation of input housing 58 including sun gear 84 gear form is meshed with planet gears 88 causing planet carrier 96 to be driven at a reduced speed. It will be appreciated that planetary gearset 14 is intended to represent any other suitable planetary arrangement providing a speed reduction and corresponding torque multiplication which is capable of use in two speed nested gear arrangement 12. Depending on the position of shift collar 40, nested gear arrangement 12 will function as a two-speed gear reduction unit that is operable to establish a first or high-range speed ratio drive connection and a second or low-range speed ratio drive connection between input gear 24 and differential assembly 16.

[0029] Referring to FIG. 3, two speed nested gear arrangement 12 is shown in a first high speed operating mode. Shift collar 40 will move axially along the extended portion 80 of differential housing 42, shifted by actuator 30 towards the left. Shift collar 40 will include three torque transmitting features, two of which will be engaged during each operational mode. Shift collar 40 will include a first torque transmitting feature 98 in the form of a spline on the inner portion of shift collar 40 which will be in continuous driving connection to differential assembly 16 and more particularly with the extended portion 80 of differential housing 42 in both operational modes. The spline 98 will engage the extended portion 80 of differential housing 42 allowingtorque transfer between shift collar 40 and differential housing 42 when either in the first position or second position. Shift collar 40 second torque transmitting feature, a plurality of inwardly extending clutch teeth 100 positioned at an inner diameter 102, will engage to the clutch teeth 66 on outer surface of the axially extending portion 64 of input housing 58 when shift collar 40 is actuated fully to the left towards input housing 58. This will provide a direct power path from input gear 24 to differential assembly 16 where torque is not multiplied and will result in a 1 : 1 ratio and differential gearset 32 distributing power to each ground engaging wheel 34.

[0030] Referring to FIG. 4, two speed nested gear arrangement 12 is shown in a second low speed operating mode. Shift collar 40 will move axially along the extended portion 80 of differential housing 42, shifted by actuator 30 but now towards the right. Shift collar 40 third torque transmitting feature, a set of radially outward extending clutch teeth 104, will engage the spline teeth 106 extending radially inward from planetary carrier 96 when shift collar 40 has been moved towards the right by actuator 30. This will result in the torque provided to input housing 58 via input gear 24 to transfer to planetary gearset 14 via sun gear 84. Torque will be increased via planetary gearset 14 and the increased torque will be provided to differential assembly 16 via the engagement of shift collar 40 to planetary carrier 96. This second operating mode will increase the torque originally provided to input gear 24 by a multiplication equivalent to the ratio of planetary gearset 14 ratio. The increased torque, with a reduction in rotational speed, will be provided to differential assembly 16 and distributed by differential gearset 32 to ground engaging wheels 34.

[0031] An optional third operating mode (not shown) where shift collar 40 is neither engaged with planetary carrier 96 or input housing 58 may also be achieved by moving actuator 30 to a position between the first and second operating locations. In this third mode, no torque transfer between the differential assembly 16 and input gear 24 may be provided. In this disconnected mode, differential assembly 16 will rotate with ground engaging wheels 34 when the vehicle is moving, but as no torque transfer occurs between shift collar 40 and input housing 58 or planetary carrier 96, first gearset 20 becomes stationary and therefore electric motor 18 would not be back driven resulting in efficiency improvements and required for an electric motor 18 utilizing permanent magnets.

[0032] FIG. 5 provides an alternative embodiment of two speed nested gear arrangement 12 where shifting clutch 28 utilizes two frictional clutches in place of shifting collar 40. A first frictional clutch 110 is positioned between the input housing 58 and the differential housing 42. A second frictional clutch 112 is positioned between the planetary carrier 96 and the differential housing 42. Frictional clutches 110 and 112 may be multiplate wet clutches which are compressed by means of actuator 30 in a controllable manner. When frictional clutch 110 is compressed, power will be transferred from input housing 58 to differential housing 42, providing a direct power path without change in ratio from the input gear 24 to differential assembly 16, similar to the first operating mode of the first embodiment. Frictional clutch 112 will not be actuated in this operating condition, resulting in no torque transfer across clutch 112. When frictional clutch 110 is engaged via being compressed, frictional clutch 112 will be open or fully disengaged. When frictional clutch 112 is closed, power will be transferred from input housing 58 to planetary gearset 14 via sun gear 84. Torque will be increased via planetary gearset 14 and the increased torque will be provided to differential assembly 16 by planetary carrier 96 via frictional clutch 112. Both clutches 110 and 112 will selectively transmit power to the extended portion 80 of differential housing 42 via splines. Utilizing frictional clutches in the place of positive locking clutches may provide beneficial operational characteristics as power may seamlessly be delivered via timing the engagement and disengagement of the frictional clutches so smooth torque transfer is provided from electric motor 18 to ground engaging wheels 34 during the shift. The positive locking clutches of the first embodiment would require a torque interrupt during the shift as shift collar 40 transitions from transmitting torque from the input housing 58 or the planetary carrier 96. The alternative embodiment may also provide a disconnected operating mode where both clutches 110 and 112 are not actuated and therefore not power transmitting, resulting in no torque transfer between the input housing 58, planetary carrier 96, and differential assembly 16.

[0033] The embodiments disclosed herein may be further described with reference to the following aspects:

[0034] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, an axle for a vehicle comprises an axle housing; a shifting clutch; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by thetorque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; and a planetary gearset driven by said sun gear; wherein the shifting clutch is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

[0035] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the torque transmitting gearset is connected to the motor via a rotor output shaft.

[0036] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the axle further includes an actuator configured to drive the shifting clutch between the first mode and the second mode.

[0037] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the axle further includes a control unit communicatively coupled to the actuator to control actuation of the shifting clutch between the first mode and the second mode.

[0038] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the differential assembly further comprises: a differential housing; a differential gearset; and a cross pin extending between the differential housing and the differential gearset; wherein the cross pin transmits power from the differential housing to the differential gearset.

[0039] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the differential assembly further comprises: a pair of side gears; and a pair of pinion gears; wherein the pair of side gears and the pair of pinion gears are encapsulated within a cavity formed in the differential housing.

[0040] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, each of the pair of side gears further include a plurality of internal splines, the plurality of internal splines being configured to mesh with a plurality of external splines formed on the axle.

[0041] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the input housing further comprises: a first open end; and a second closed end opposite the first open end, the second closed end including an axially extending portion having a plurality of clutch teeth formed about an outer diameter of the axially extending portion; wherein the plurality of clutch teeth are configured to engage an actuator, the actuator being configured to drive the shifting clutch between the first mode and the second mode.

[0042] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, an axial thrust bearing is positioned between the input housing and the differential assembly, the axial thrust bearing being configured to prevent translation of the input housing in at least a first axial direction.

[0043] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, a snap ring is positioned between the input housing and the differential assembly, the snap ring being configured to prevent translation of the input housing in at least a second axial direction opposite the first axial direction.

[0044] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the shifting clutch includes an axially moving shift collar.

[0045] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the axially moving shift collar comprises: a first torque transmitting mechanism including a spline coupled to the differential assembly; a second torque transmitting mechanism including a plurality of torque transmitting clutch teeth configured to engage a plurality of clutch teeth formed on the input housing; and a third torque transmitting mechanism including a plurality of radially extending clutch teeth configured to engage the planetary gearset.

[0046] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the plurality of torque transmitting clutch teeth engage the plurality of clutch teeth when the shifting clutch is translated to the first mode.

[0047] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the plurality of radially extending clutch teeth engage the planetary gearset when the shifting clutch is translated to the second mode.

[0048] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, input gear generates a first torque when the shifting clutch is translated to the first mode, and a second torque when the shifting clutch is translated to the second mode, such that the second torque is greater than the first torque.

[0049] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the shifting clutch is further translatable to a third mode, the third mode being positioned between the first mode and the second mode.

[0050] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the differential assembly is disconnected from the input gear when the shifting clutch is in the third mode.

[0051] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, the shifting clutch comprises: a first frictional clutch positioned between the input housing and the differential assembly; and a second frictional clutch positioned between the planetary gearset and the differential assembly.

[0052] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, an axle for a vehicle comprises an axle housing; an axially moving shift collar; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by the torque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; a planetary gearset driven by said sun gear; and an actuator configured to drive the axially moving shift collar; wherein the axially moving shift collar is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

[0053] According to one aspect of the disclosure, and potentially in combination with other disclosed aspects of the disclosure, an axle for a vehicle comprises an axle housing; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by the torque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; a planetary gearset driven by said sun gear; a shifting clutch comprising: a first frictional clutch positioned between the input housing and the differential assembly; and a second frictional clutch positioned between the planetary gearset and the differential assembly; and an actuator configured to drive the shifting clutch; wherein the shifting clutch is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

[0054] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varies in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of disclosure.

Claims

CLAIMSWhat is claimed is:

1. An axle for a vehicle comprising: an axle housing; a shifting clutch; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by the torque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; and a planetary gearset driven by said sun gear; wherein the shifting clutch is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

2. The axle of claim 1, wherein the torque transmitting gearset is connected to the motor via a rotor output shaft.

3. The axle of claim 1, further comprising an actuator configured to drive the shifting clutch between the first mode and the second mode.

4. The axle of claim 3, further comprising a control unit communicatively coupled to the actuator to control actuation of the shifting clutch between the first mode and the second mode.

5. The axle of claim 1, wherein the differential assembly further comprises: a differential housing; a differential gearset; and a cross pin extending between the differential housing and the differential gearset; wherein the cross pin transmits power from the differential housing to the differential gearset.

6. The axle of claim 5, wherein the differential assembly further comprises: a pair of side gears; and a pair of pinion gears; wherein the pair of side gears and the pair of pinion gears are encapsulated within a cavity formed in the differential housing.

7. The axle of claim 6, wherein each of the pair of side gears further include a plurality of internal splines, the plurality of internal splines being configured to mesh with a plurality of external splines formed on the axle.

8. The axle of claim 1, wherein the input housing further comprises: a first open end; and a second closed end opposite the first open end, the second closed end including an axially extending portion having a plurality of clutch teeth formed about an outer diameter of the axially extending portion; wherein the plurality of clutch teeth are configured to engage an actuator, the actuator being configured to drive the shifting clutch between the first mode and the second mode.

9. The axle of claim 1, further comprising an axial thrust bearing positioned between the input housing and the differential assembly, the axial thrust bearing being configured to prevent translation of the input housing in at least a first axial direction.

10. The axle of claim 9, further comprising a snap ring positioned between the input housing and the differential assembly, the snap ring being configured to prevent translation of the input housing in at least a second axial direction opposite the first axial direction.

11. The axle of claim 1, wherein the shifting clutch includes an axially moving shift collar.

12. The axle of claim 11, wherein the axially moving shift collar comprises: a first torque transmitting mechanism including a spline coupled to the differential assembly; a second torque transmitting mechanism including a plurality of torque transmitting clutch teeth configured to engage a plurality of clutch teeth formed on the input housing; and a third torque transmitting mechanism including a plurality of radially extending clutch teeth configured to engage the planetary gearset.

13. The axle of claim 12, wherein the plurality of torque transmitting clutch teeth engage the plurality of clutch teeth when the shifting clutch is translated to the first mode.

14. The axle of claim 12, wherein the plurality of radially extending clutch teeth engage the planetary gearset when the shifting clutch is translated to the second mode.

15. The axle of claim 1, wherein the input gear generates a first torque when the shifting clutch is translated to the first mode, and a second torque when the shifting clutch is translated to the second mode, such that the second torque is greater than the first torque.

16. The axle of claim 1, wherein the shifting clutch is further translatable to a third mode, the third mode being positioned between the first mode and the second mode.

17. The axle of claim 16, wherein the differential assembly is disconnected from the input gear when the shifting clutch is in the third mode.

18. The axle of claim 1, wherein the shifting clutch comprises: a first frictional clutch positioned between the input housing and the differential assembly; and a second frictional clutch positioned between the planetary gearset and the differential assembly.

19. An axle for a vehicle comprising: an axle housing; an axially moving shift collar; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by the torque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; a planetary gearset driven by said sun gear; and an actuator configured to drive the axially moving shift collar; wherein the axially moving shift collar is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

20. An axle for a vehicle comprising: an axle housing; a differential assembly rotationally supported by the axle housing via a pair of bearings; a motor configured to provide power to a torque transmitting gearset; an input gear driven by the torque transmitting gearset; an input housing driven by the input gear surrounding and supported by the differential assembly; a sun gear driven by the input housing; a planetary gearset driven by said sun gear; a shifting clutch comprising: a first frictional clutch positioned between the input housing and the differential assembly; and a second frictional clutch positioned between the planetary gearset and the differential assembly; and an actuator configured to drive the shifting clutch; wherein the shifting clutch is translatable between a first mode where the input gear is directly coupled to the differential assembly and a second mode where the differential assembly is driven by the planetary gearset.

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