Disconnecting differential mechanism for a motor vehicle

Abstract

The present disclosure relates to electric vehicles and electric drive trains for such electric vehicles. The electric drive train is configured to include an electric motor and a disconnectable differential assembly arranged for transmitting a motive power generated by the electric motor to a pair of ground engaging wheels. The disconnectable differential assembly includes a power transmission mechanism driven by the electric motor, a differential mechanism interconnected with the pair of ground engaging wheels, and a power operated disconnect mechanism for selectively coupling and uncoupling the power transmission mechanism and the differential mechanism.

Description

[0001] Cross-references to related applications

[0002] This PCT international patent application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 116,999, filed November 23, 2020, and U.S. Provisional Patent Application No. 63 / 156,389, filed March 4, 2021, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure generally relates to differential assemblies of a type used in motor vehicles, wherein the differential assembly is configured to include a power transmission mechanism, a differential mechanism, and a power-operated disconnect mechanism operable to selectively engage and disengage the differential mechanism and the power transmission mechanism. This disclosure also relates to electric drive systems, such as electric axle assemblies, equipped with such "disengageable" differential assemblies. Background Technology

[0004] This section provides background information in connection with this disclosure, which is not necessarily prior art.

[0005] Given that most motor vehicle OEMs have recently focused on developing electric vehicles (EVs), significant engineering activity has been directed towards effectively encapsulating electric powertrains for installation in EVs. In many configurations, the electric powertrain is the sole or “primary” electric powertrain and is operable to generate prime movers (i.e., drive torque) and transmit them to a single pair of wheels, typically the front wheels. However, in addition to the primary electric powertrain, attention has also turned to the development of EVs with a “secondary” electric powertrain capable of generating prime movers and transmitting them to another pair of wheels, such as the rear wheels, to establish a four-wheel drive (4WD) vehicle. The secondary electric powertrain may include an electric motor that drives a differential assembly, which is encapsulated as an electrically driven axle. When 4WD mode is not required, it is known to selectively “disengage” the secondary electric powertrain by disconnecting the differential assembly from the electric motor via a power-operated disconnect device.

[0006] Given the current focus on the development of optimized auxiliary electric powertrains, the structural and functional interaction of the disconnection device for power operation between the electric motor and the differential assembly is important. Therefore, there is a need to develop a "disconnectable" differential assembly for use in auxiliary electric powertrain applications, constructed to advance existing technologies. Summary of the Invention

[0007] This section provides an overview of many aspects associated with the inventive concept embodied in the teachings of this disclosure, and is not intended to be considered as a complete list of its entire scope of protection or all its features and advantages.

[0008] One aspect of this disclosure is to provide an electric powertrain with a disconnectable differential assembly configured for use in motor vehicle powertrains and / or powertrain applications, and embodies the inventive concept set forth in the following detailed description and shown in the accompanying drawings.

[0009] In this respect, the disconnectable differential assembly disclosed herein is typically associated with an electric powertrain and is configured as an electric drive axle or drive shaft of the type used in partially or fully electric vehicles for transmitting prime movers (i.e., drive torque) from an electric motor to a pair of ground-engaged wheels.

[0010] The disengageable differential assembly disclosed herein is configured to typically include a power transmission mechanism driven by an electric motor, a differential mechanism drivably connected to a ground-engaging wheel, and a power-operated disconnect mechanism capable of operating in a first or "connected" mode to engage the power transmission mechanism to the differential mechanism, and also capable of operating in a second or "disconnected" mode to disconnect the power transmission mechanism from the differential mechanism.

[0011] In various alternative and non-limiting embodiments of the disconnectable differential assembly associated with this disclosure, the power transmission mechanism is configured to include a ring gear adapted to be driven by an electric motor, and an outer housing fixed for rotating with the ring gear and together defining an internal cavity. Furthermore, the differential mechanism is rotatably disposed within the internal cavity and includes a differential carrier supporting the differential gear set. Additionally, the power-operated disconnect mechanism is configured to include a clutch unit disposed between the housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a first or "engaged" state for establishing a connection mode and a second or "disengaged" state for establishing a disconnect mode.

[0012] The power-operated disconnect mechanism associated with each alternative embodiment of the disconnectable differential assembly is configured with a clutch unit having a first clutch member fixed for rotation with the differential carrier of the differential mechanism and a second clutch member coupled for rotation with the housing of the power transmission mechanism. The second clutch member is axially movable between a first or "retracted" position and a second or "extended" position. In the first or "retracted" position, the pawl teeth on the second clutch member disengage from the clutch teeth on the first clutch member to establish a "released" state of the clutch unit. In the second or "extended" position, its pawl teeth drive into engagement with the clutch teeth on the first clutch member to establish an "engaged" state of the clutch unit. A biasing device is provided for generally biasing the second clutch member toward its retracted position. The electromagnetic actuator unit is non-rotatably mounted outside the housing and includes an annular solenoid and a movable actuating element configured as a magnetic plunger. The clutch actuation mechanism interconnects the plunger with the second clutch member, such that movement of the plunger between a first or "disengaged" position and a second or "engaged" position causes corresponding movement of the second clutch member between its retracted and extended positions, while simultaneously promoting rotation of the second clutch member relative to the plunger. Energization of the solenoid causes the plunger to move from its disengaged position to its engaged position against a bias applied by a biasing device. De-energization of the solenoid allows the biasing device to force the plunger back to its disengaged position.

[0013] According to a first non-limiting embodiment, the first clutch member is a face clutch having clutch teeth extending axially from the differential carrier, and the second clutch member is a claw plate clutch sleeve having a cylindrical sleeve portion with external splines and a claw plate portion with axially extending claw teeth. The external splines on the cylindrical sleeve portion continuously engage with internal splines formed in the housing to allow the claw plate clutch sleeve to rotate together with the power transmission mechanism while allowing axial movement of the claw plate clutch sleeve. The claw teeth on the claw plate portion are configured to disengage from engagement with the clutch teeth when the claw plate clutch sleeve is in its retracted position when the solenoid is de-energized, and are also configured to drive engagement with the clutch teeth when the claw plate clutch sleeve is in its extended position when the solenoid is energized. The clutch actuation mechanism is configured to include a first actuation plate latched to a plunger, a second actuation plate having an actuation protrusion having a cut through a housing and latched to a claw-plate clutch sleeve, and a thrust bearing operably disposed between the first and second actuation plates.

[0014] According to a second non-limiting embodiment, the first clutch member is a radial clutch having clutch teeth extending radially outward from the differential carrier, and the second clutch member is a radial clutch sleeve having external splines and internal claw teeth. The external splines continuously engage with the internal splines formed in the housing to facilitate the co-rotation of the radial clutch sleeve and the power transmission mechanism, while allowing axial movement of the radial clutch sleeve. The radial claw teeth are configured to disengage from engagement with the radial clutch teeth when the radial clutch sleeve is in its retracted position, and are also configured to drively engage with the clutch teeth when the radial clutch sleeve is in its extended position. The clutch actuation mechanism is again configured to have a first actuating plate latched to a plunger, a second actuating plate having an actuating tab that passes through a cutout in the housing and latches to the radial clutch sleeve, and a thrust bearing operably disposed between the first and second actuating plates.

[0015] According to a third non-limiting embodiment, the first clutch member is a face clutch having clutch teeth extending axially from the differential carrier, and the second clutch member is a claw-shaped plate ring having a claw plate and a plurality of drive lugs with external splines. The claw plate has axially extending claw teeth, and the plurality of drive lugs with external splines extend axially from the claw plate and through a housing cutout. The external splines on the drive lugs continuously engage with internal splines formed in the housing to facilitate co-rotation with the claw-shaped plate ring and axial movement of the claw-shaped plate ring relative to the housing. The claw teeth are configured to displace from engagement with the clutch teeth when the claw-shaped plate ring is in its retracted position, and are also configured to drively engage with the clutch teeth when the claw-shaped plate ring is in its extended position. The clutch actuation mechanism is configured to have: a first actuating plate latched to a plunger; a second actuating plate latched to the drive lugs; and a thrust bearing disposed between the first and second actuating plates.

[0016] According to a fourth non-limiting embodiment, the first clutch member is a face clutch having clutch teeth extending axially from the differential carrier, and the second clutch member is a stamped claw ring having external splines and axially extending claw teeth. The external splines continuously engage with internal splines formed in the housing to connect the stamped claw ring plate for rotation with the housing while allowing axial sliding motion relative to the housing. The claw teeth are configured to disengage from the clutch teeth when the stamped claw ring is in its retracted position and are also configured to drively engage the clutch teeth when the stamped claw ring is in its extended position. The clutch actuation mechanism includes: a first actuating plate latched to a plunger; a second actuating plate having a plurality of drive flanges extending through a housing cutout and secured to the stamped claw ring; and a thrust bearing disposed between the first and second actuating plates.

[0017] According to another alternative, non-limiting embodiment, the plunger is mounted on a slidable support sleeve. The clutch actuation mechanism includes: a first actuating plate latching to the support sleeve; a second actuating plate having guide tabs extending into a housing cutout and latching to a plurality of drive lugs extending from a claw-shaped ring; and a thrust bearing disposed between the first and second actuating plates. The claw-shaped ring includes an external spline continuously engaging with an internal spline formed in the housing. The claw-shaped ring also includes axially extending claw teeth configured to selectively engage clutch teeth on a face clutch defining a first clutch member in response to movement of the claw-shaped ring between its retracted and extended positions. The support sleeve and the plunger move in unacted and actuated positions to move the claw-shaped ring between its corresponding retracted and extended positions of the clutch actuation mechanism.

[0018] According to other features of this disclosure, the solenoid unit is located in a fixed support structure, such as a transmission housing or axle housing. Gaskets and retaining rings are used to ensure proper positioning of the solenoid unit relative to the actuation mechanism. The plunger may also be configured to include a tapered portion on its outer diameter leading edge relative to the core housing. This tapered portion allows for more consistent force throughout the entire axial plunger stroke, resulting in smoother engagement.

[0019] Other areas of application will become apparent from the detailed description and accompanying drawings disclosed herein. Therefore, the descriptions and specific examples set forth in the Summary Section are intended to limit particular aspects and features of this disclosure and not to limit the scope of protection to which the inventive concept is given. Attached Figure Description

[0020] The accompanying drawings described herein are intended to illustrate certain features of alternative and non-limiting embodiments, and do not limit the scope of protection afforded to the inventive concept associated with this disclosure. These drawings include:

[0021] Figure 1 This is a schematic diagram of a vehicle architecture for an exemplary electric vehicle (EV) equipped with a main electric drive system for driving a set of primary (i.e., front) ground-engaged wheels, a secondary electric drive system for selectively driving a set of secondary (i.e., rear) ground-engaged wheels, and a control system for controlling the operation of both the main drive system and the secondary drive system.

[0022] Figure 2 This is a partial cross-sectional view of a disconnectable differential assembly, which is related to... Figure 1 The auxiliary electric drive system shown is associated and is typically configured to include a power transmission mechanism, a differential mechanism, and a power-operated disconnect mechanism.

[0023] Figure 3A and Figure 3B yes Figure 2 The diagram shows an overall cross-sectional view of a disconnectable differential assembly having a power-operated disconnect mechanism with an electromagnetic actuator unit operable to selectively switch a clutch unit between a first state and a second state.

[0024] Figure 4 Is with Figure 3A and Figure 3B Isometric view of the axially movable claw-shaped clutch sleeve associated with the clutch unit shown in the figure;

[0025] Figure 5 yes Figure 3A and Figure 3B The image shows an isometric view of a differential mechanism, which includes a differential carrier, a differential gear set supported by the differential carrier, and a face clutch plate extending from the differential carrier and associated with a clutch unit.

[0026] Figure 6A and Figure 6B Is with Figure 3A and Figure 3B An isometric view of the housing associated with the power transmission mechanism shown;

[0027] Figure 7A and Figure 7B This is an overall cross-sectional view illustrating an alternative, non-limiting implementation of a disconnectable differential assembly configured for installation on... Figure 1 The auxiliary electric drive system shown includes an electromagnetic actuator unit that can be operated to selectively switch the clutch unit between a first state and a second state.

[0028] Figure 8 Is with Figure 7A and Figure 7B An isometric view of the axially movable radial clutch sleeve associated with the clutch unit shown in the diagram.

[0029] Figure 9 yes Figure 7A and Figure 7B The isometric view of the differential mechanism shown, which includes a differential carrier, a differential gear set supported by the differential carrier, and a radial clutch hub extending from the differential carrier and associated with the clutch unit.

[0030] Figure 10A and Figure 10B Is with Figure 7A and Figure 7B An isometric view of the housing associated with the power transmission mechanism shown;

[0031] Figure 11A and Figure 11B This is an overall cross-sectional view, illustrating the configuration for installation. Figure 1 Another alternative, non-limiting implementation of the disconnectable differential assembly within the auxiliary electric powertrain;

[0032] Figure 12A and Figure 12B Is with Figure 11A and Figure 11B Isometric view of the axially movable claw-shaped plate ring associated with the clutch unit shown;

[0033] Figure 13 It is similar to Figure 5 An isometric view, illustrating the relationship with Figure 11A and Figure 11B The disconnectable differential assembly shown is associated with the differential mechanism and face clutch plate.

[0034] Figure 14A and Figure 14B Is with Figure 11A and Figure 11B An isometric view of the housing diagram associated with the power transmission mechanism shown;

[0035] Figure 15 This is an overall cross-sectional view of yet another alternative, non-limiting embodiment of a disconnectable differential assembly constructed according to the teachings of this disclosure.

[0036] Figure 16A and Figure 16B Is with Figure 15 Isometric view of the axially movable claw-shaped plate ring associated with the clutch unit shown;

[0037] Figure 17 It is similar to Figure 5 and Figure 13 An isometric view, illustrating the relationship with Figure 15 The disconnectable differential assembly is associated with the differential mechanism and face clutch plate.

[0038] Figure 18A and Figure 18B Is with Figure 15 An isometric view of the housing unit associated with the power transmission mechanism shown in the diagram;

[0039] Figure 19 This is an overall cross-sectional view of another alternative, non-limiting embodiment of a disconnectable differential assembly constructed according to the teachings of the present invention.

[0040] Figure 20 Is with Figure 19 An isometric view of the axially movable claw clutch ring associated with the clutch unit shown in the diagram.

[0041] Figure 21 yes Figure 20 The image shows a partial isometric view of a claw-shaped clutch ring, which is securely fixed to... Figure 19 The actuator plate associated with the electromagnetic actuator unit shown;

[0042] Figure 22 Is with Figure 19 Isometric view of the differential mechanism and axial face clutch plate configuration associated with the disconnectable differential assembly;

[0043] Figure 23A and Figure 23B Is with Figure 19 Isometric front and rear views of the claw clutch ring associated with the clutch unit;

[0044] Figure 24A and Figure 24B Is with Figure 19 Isometric front and rear views of the actuator plate associated with the electromagnetic actuator unit shown;

[0045] Figure 25A and Figure 25B Is with Figure 19 Isometric view of the two-piece housing unit associated with the power transmission mechanism of the disconnectable differential assembly.

[0046] Figures 26A to 26D It shows the relationship with Figure 19 Additional features of the claw clutch ring and actuation components associated with the disconnectable differential assembly shown;

[0047] Figures 27A to 27D It shows the relationship with Figure 19 Other features of the claw clutch ring and actuating components associated with the disconnectable differential assembly shown;

[0048] Figure 28 It is illustrated with Figure 19 A partial cross-sectional view of the position sensing configuration associated with the electromagnetic actuator unit shown in the figure;

[0049] Figure 29 It is illustrated with Figure 19 A partial cross-sectional view of an alternative position sensing configuration associated with the electromagnetic actuator unit shown in the figure;

[0050] Figures 30A to 30C This is an overall cross-sectional view of another non-limiting embodiment of a disconnectable differential assembly constructed according to the teachings of this disclosure;

[0051] Figure 31 yes Figures 30A to 30CThe partial cross-sectional view of the disconnectable differential assembly shown shows that its clutch unit is in a released state in response to the operation of the electromagnetic actuator unit in a first or "de-energized" state.

[0052] Figure 32 Similar to Figure 31 In addition, the clutch unit is engaged in response to the operation of the electromagnetic actuator unit in the second or "energized" state;

[0053] Figure 33A and Figure 33B Is with Figures 30A to 30C An isometric view of the claw clutch ring associated with the clutch unit of the disconnectable differential assembly shown.

[0054] Figure 34A and Figure 34B Is with Figures 30A to 30C An isometric view of the housing associated with the power transmission mechanism of the disconnectable differential assembly shown.

[0055] Figure 35 and Figure 36 This is a partial isometric view, illustrating the installation to... Figure 34A and Figure 34B The outer shell is used for common rotation and relative axial movement. Figure 33A and Figure 33B Claw-shaped clutch ring;

[0056] Figure 37 It shows the relationship with Figures 30A to 30C An overall cross-sectional view of the alternative mounting arrangement of the electromagnetic actuator associated with the disconnectable differential assembly shown; and

[0057] Figure 38 and Figure 39 The diagram illustrates the use of... Figures 30A to 30C and Figure 37 The electromagnetic actuator unit shown uses a tapered plunger configuration.

[0058] Figure 40 This is a partial cross-sectional view of another non-limiting embodiment of a disconnectable differential assembly constructed according to the teachings of this disclosure;

[0059] Figure 41 This is a partial cross-sectional view of another non-limiting embodiment of a disconnectable differential assembly constructed according to the teachings of this disclosure;

[0060] Throughout the various views in the accompanying drawings, corresponding reference numerals denote the corresponding components. Detailed Implementation

[0061] Example embodiments of various alternative configurations of a disconnectable differential assembly incorporating the inventive concept of this disclosure will now be described more fully with reference to the accompanying drawings. Those skilled in the art will fully understand all aspects, features, and potential improvements associated with the inventive concept embodied in each of the alternative configurations shown in the drawings and described in detail herein.

[0062] First pay attention Figure 1 An exemplary vehicle structure for an electric vehicle 10 is generally shown as including: a main (i.e., front) electric drivetrain 12 configured to generate prime mover (i.e., drive torque) and transmit it to a pair of main (i.e., front) ground-engaged wheels 14; a secondary (i.e., rear) electric drivetrain 16 configured to selectively generate drive torque and transmit it to a pair of secondary (i.e., rear) ground-engaged wheels 18; and a control system 20 operable to control the main drivetrain 12 and the secondary drivetrain 16. The main drivetrain 12 is schematically shown as including: a main electric motor 22; a drive axle 24 driven by the main electric motor 22; and a pair of main drive shafts 26 interconnecting the main wheels 14 to a main differential assembly (not specifically shown) associated with the drive axle 24. The drive torque generated by the main electric motor 22 can be multiplied via one or more gear sets within the drive axle 24 and delivered to the main wheels 14 to define a two-wheel drive (2WD) mode of vehicle operation.

[0063] Stay tuned Figure 1 The secondary drivetrain 16 is schematically shown as including: a secondary electric motor 30; a disconnectable differential assembly 32 selectively driven by the secondary electric motor 30; and a pair of secondary drive shafts 34 interconnecting the secondary wheels 18 with the differential assembly 32. As will be described in more detail, the disconnectable differential assembly 32 is generally configured to include: a power transmission mechanism 36 driven by the secondary electric motor 30; a differential mechanism 38 interconnected with the secondary drive shafts 34; and a power-operated disconnect mechanism 40 operable to selectively engage and disengage the output of the power transmission mechanism 36 from the input of the differential mechanism 38. When the disconnect mechanism 40 operates in a first or "engaged" mode, the secondary electric motor 30 transmits drive torque to the secondary wheels 18, which, together with the drive torque transmitted to the primary wheels 14 via the primary electric motor 22, defines a four-wheel drive (4WD) mode for vehicle operation. The control system 20 is schematically shown as typically including a controller 44 configured to control the operation of the main motor 22, the auxiliary motor 30, and the power-operated disconnect mechanism 40 in response to a number of vehicle inputs (indicated by vehicle sensor 48), and is powered by a power source (indicated by battery 46).

[0064] Now refer to the specific details. Figure 2 , Figure 3A and Figure 3B A first non-limiting embodiment of the disconnect differential assembly 32 will be described. The power transmission mechanism 36 is generally shown as including a ring gear 50 and a bell-shaped housing 52 fixed to the ring gear 50 for rotation about a common axis "X". The ring gear 50 is adapted to be driven by the output gear 54 of the auxiliary electric motor 30. Figure 1 Driven by a ring gear 50 and a housing 52, a pair of laterally spaced cylindrical bosses 56A, 56B are defined on which the disconnectable differential assembly 32 is rotatably supported in the housing (not shown) via a pair of laterally spaced bearing assemblies 58A, 58B (see FIG. 30a). The axial hub section 52A and the radial ring section 52B of the housing 52 mate with the plate portion 50A of the ring gear 50 to define an internal cavity 60 in which the differential mechanism 38 is supported for rotation about the "X" axis.

[0065] The differential mechanism 38 is shown as comprising: a differential carrier 62; a pair of differential portions 64 rotatably mounted on a pinion strut 66, the opposite ends of which are fixed in pole holes 68 formed in the differential carrier 62; and a pair of differential side gears 70, each meshing with one of the two differential pinions 64. As is conventional, each differential side gear 70 has an internal spline 72 configured to mesh with an external spline formed on the secondary drive shaft 34, thereby drivingly connecting the output of the differential mechanism 38 to the secondary wheel 18. The differential mechanism 38 is rotatably supported within an internal cavity 60 of the power transmission mechanism 36. Figure 5 As best shown, a plurality of axially extending clutch teeth 74 are formed on the outer end surface 76 of the differential carrier 62 to define a first clutch member configured as a face clutch 78.

[0066] The power-operated disconnect mechanism 40 is shown as typically comprising an electromagnetic actuator unit 80, a clutch unit 82, a clutch actuation unit 84, and a biasing device 86. The electromagnetic actuator unit 80 is annular in configuration and oriented around a central boss section 52C of the housing 52. The electromagnetic actuator unit 80 is non-rotatably supported on the central boss section 52C via a tubular bushing 90 and includes a solenoid 92, a clamshell-type pole or core housing 94 encapsulating and surrounding the solenoid 92, and a plunger 96 supported on the bushing 90 for axial sliding motion. In addition to the face clutch ring 78 on the differential carrier 62, the clutch unit 82 includes a second clutch member shown as a claw-plate clutch sleeve 100, configured to rotate with the housing 52 of the power transmission mechanism 36 and to move axially relative to the face clutch ring 78. Figure 4 The best illustration shows a plurality of four (4) equally spaced sector portions 102 with external splines formed on the outer surface 104 of the sleeve portion of the claw plate clutch sleeve 100. Figure 6A and Figure 6B The diagram illustrates a plurality of four (4) equally spaced sector portions 106 with internal splines formed in the axial section 52A of the housing 52. The sector portions 102 with external splines on the claw plate clutch sleeve 100 continuously engage with the sector portions 106 with internal splines in the housing 52, thereby connecting the claw plate clutch sleeve 100 to rotate together with the housing 52, but being able to move axially relative to the housing 52. Figure 6A and Figure 6B Also illustrated are a plurality of four (4) windows or cutouts 108 formed in the annular segment 52B of the housing 52 and aligned with the sector portion 106 with internal splines. The claw plate clutch sleeve 100 is also shown as including a claw ring portion 110 extending from the sleeve portion, and the claw ring portion 110 is formed to include axially extending claw teeth 112.

[0067] Clutch actuation unit 84 in Figure 2The assembly, best shown in Figure 3, typically comprises a first actuating plate 116, a second actuating plate 118, and a thrust bearing 120. The first actuating plate 116 engages a plunger 96, the second actuating plate 118 has a plurality of four (4) actuating tabs 122 extending through a cutout 108 in the housing 52 and engaging the claw ring portion 110 of the claw plate clutch sleeve 100, and the thrust bearing 120 is disposed between the first actuating plate 116 and the second actuating plate 118. Because the actuating tabs 122 pass through the cutout 108, the second actuating plate 118 rotates together with the power transmission mechanism 36. Similarly, because the first actuating plate is non-rotatable, the thrust bearing 120 accommodates relative rotation between the first actuating plate 116 and the second actuating plate 118. The biasing device 86 is configured as one or more spring plates acting between the end surface 103 of the claw plate clutch sleeve 100 and the ring portion 50A of the ring gear 50.

[0068] According to the preferred operating configuration, when the electromagnetic actuator unit 80 operates in the "de-energized" state, the disconnectable differential assembly 32 is generally capable of operating in the disconnected mode and can switch to the engaged mode in response to the electromagnetic actuator unit 80 being positioned in the "energized" state. More specifically, when the disconnected mode is established, the clutch unit 82 operates in the "released" state, and when the engaged mode is established, the clutch unit 82 operates in the "engaged" state. The release state of the clutch unit 82 is established when the biasing device 86 positions the clutch sleeve 100 in the retracted position, in which the claw teeth 112 of the clutch sleeve 100 disengage from engagement with the clutch teeth 74 on the face clutch plate 78. This axial movement of the claw clutch sleeve 100 to its retracted position forces the plunger 96 to move axially relative to the solenoid 92 to an unactuated position due to the interconnection established between them via the clutch actuator unit 84. With the claw-shaped clutch sleeve 100 in its retracted position, the differential carrier 62 is not driven connected to the housing 52, thereby disconnecting the differential mechanism 38 from the power transmission mechanism 36. Therefore, no drive torque is transmitted from the auxiliary electric motor 30 to the second wheel 18 via the disconnectable differential assembly 32.

[0069] When torque needs to be transmitted from the auxiliary electric motor 30 to the second wheel 18, the disconnect differential assembly 32 is switched to its engaged mode by energizing the solenoid 92 by switching the electromagnetic actuator unit 80 to its energized state. The magnetic circuit generated when the solenoid 92 is energized causes the magnetic plunger 96 to move axially from its non-actuated position to its actuated position, which in turn causes the claw clutch sleeve 100 to move from its retracted position to its extended position, in which the claw teeth 112 of the claw clutch sleeve 100 engage with the clutch teeth 74 on the face clutch plate 78. This movement of the plunger 96 to its actuated position and the claw clutch sleeve 100 to its extended position due to the energization of the solenoid 92 is opposite to the bias applied to it by the spring plate 86. With the claw clutch sleeve 100 positioned and held in its extended position, the differential carrier 62 is driven to the housing 52, thereby connecting the differential mechanism 38 to the power transmission mechanism 36. Therefore, the drive torque generated by the auxiliary electric motor 30 is transmitted from the disconnectable differential assembly 32 to the auxiliary wheel 18 to establish a 4WD mode. Furthermore, when the auxiliary electric motor 30 is not transmitting torque via regenerative control associated with the control system 20, power regeneration can be controlled by switching the disconnectable differential assembly 32 to its connected mode.

[0070] Now focus on the attached diagram. Figures 7A to 10B A second, non-limiting embodiment of the disconnectable differential assembly 132 will now be described. Since many of the components shown in association with the disconnectable differential assembly 132 are substantially similar in both structure and function to those previously described for the disconnectable differential assembly 32, common reference numerals are used, and further explanation is unnecessary. In particular, the disconnectable differential assembly 132 is configured to include a modified clutch unit 134, which includes a radial clutch sleeve 136 (…). Figure 8 ) and clutch hub 138 ( Figure 9 The clutch sleeve 136 again includes a plurality of four (4) externally splined sector portions 102 formed on the outer surface 104, which continuously engage with internally splined sector portions 106 formed in the hub section 52A of the housing 52. Thus, the clutch sleeve 136 is again configured to rotate with the housing 52 and to be axially movable relative to the clutch hub 138 between a retracted position and an extended position. However, the clutch sleeve 136 now includes radially inwardly extending radially inwardly extending radially from the inner surface 105. The radially extending ...

[0071] Figure 9The diagram illustrates a clutch hub 138 formed on the outer peripheral surface 144 of a differential carrier 62, and includes radial clutch teeth 146 extending radially outward from the outer surface 144. The clutch teeth 146 are axially aligned to define a double row of teeth including a first clutch tooth 146A and a second clutch tooth 146B, which are separated by a toothless clearance 148. Figure 7A and Figure 7B The diagram illustrates the clutch sleeve 136 in its retracted position, wherein when the electromagnetic actuator unit 80 operates in its de-energized state, the clutch actuation unit 84 simultaneously positions the plunger 96 in its non-actuated position due to the bias applied to it via the spring plate 86. Therefore, the clutch unit 134 is in its released state for establishing the disengagement mode of the disconnectable differential assembly 132. As shown, positioning the clutch sleeve 136 in its retracted position disengages the first claw 140A from the first clutch tooth 146A and also disengages the second claw 140B from the second clutch tooth 146B. Thus, the differential carrier 62 is disconnected from the housing 52.

[0072] The disconnectable differential assembly 132 is configured to operate normally in its disconnected mode, but can be switched to its engaged mode in response to the electromagnetic actuator unit 80 being positioned in its energized state. When the solenoid 92 is energized, the magnetic plunger 96 moves axially from its non-actuated position to its actuated position, which in turn causes the clutch sleeve 136 to slide axially from its retracted position to its extended position against the bias exerted on it by the spring plate 86. This switching of the clutch unit 134 to its engaged state serves to move the first claw 140A to engage the first clutch tooth 146A, while simultaneously moving the second claw 140B to engage the second clutch tooth 146B. Thus, the differential carrier 62 is now coupled for rotation with the housing 52, thereby connecting the differential mechanism 38 to the power transmission mechanism 36.

[0073] Now pay special attention to the attached diagram. Figures 11A to 14B A third, non-limiting embodiment of the disconnect differential assembly 232 will now be described. Again, common reference numerals are used in these figures to identify components of the disconnect differential assembly 232 that are structurally and / or functionally similar to those previously described as associated with disconnect differential assemblies 32 and 132. The differential mechanism 38 is generally similar to... Figure 5The differential mechanism shown includes a face clutch ring 78 with axially extending clutch teeth 74. The disconnectable differential assembly 232 is configured to include a modified clutch unit 234 and a slightly modified clutch actuation unit 84'. Regarding the clutch unit 234, it now includes a claw-shaped clutch ring 236 located axially between the differential mechanism 38 and the electromagnetic actuator unit 40. Figure 12A and Figure 12B This contrasts with the coaxial relationship of the clutch sleeves 100, 136 disposed between the housing 50 and the differential carrier 62 in the previously disclosed embodiments. The claw clutch ring 236 is configured to include a claw ring section 238 and a plurality of four (4) drive lugs 242, the claw ring section 238 being formed to include axially extending claw teeth 240, the plurality of four (4) drive lugs 242 extending axially from the claw ring section 238 and having external spline teeth 246. As shown, the drive lugs 242 extend through the housing 52 ( Figure 14A and Figure 14B The cuts 108 in the ) and their spline teeth 246 engage with the internal spline 106 formed in the housing 52. Thus, the claw clutch ring 236 is configured to rotate together with the power transmission mechanism 36 and is capable of axial sliding movement relative to the face clutch 78 on the differential carrier 62 between its retracted and extended positions.

[0074] The clutch actuation unit 84' is now configured such that the second actuation plate 118' has a plurality of four (4) locking flanges 250 oriented to engage and latch with the drive lugs 242 on the claw clutch ring 236. Thus, movement of the plunger 96 between its non-actuated and actuated positions results in corresponding movement of the claw clutch ring 236 between its retracted and extended positions. The biasing device 86' has been repositioned to place a wave spring (or equivalent biasing device) between the second actuation plate 118' and the ring portion 52B of the housing 52. As shown, the biasing device 86' is configured to generally bias the claw clutch ring 236 toward its retracted position via the clutch actuation unit 86', which also serves to bias the plunger 96 toward its non-actuated position when the electromagnetic actuator unit 40 is in its de-energized state. As shown, the positioning of the claw clutch ring 236 in its retracted position is used to disengage the claw teeth 240 on the claw ring section 238 from the clutch teeth 74 on the face clutch 78, thereby placing the clutch unit 234 in its released state so as to switch the disconnect differential assembly 232 to its disconnected mode.

[0075] The disconnectable differential assembly 232 can switch to its engaged mode in response to energization of the solenoid 92, causing the magnetic plunger 96 to slide from its inactive position to its engaged position, and this in turn causes the claw clutch ring 236 to slide axially from its retracted position to its extended position against the bias applied thereon by the biasing device 86'. The switching of the clutch unit 234 to its engaged state is used to move the claw teeth 240 on the claw clutch ring 236 to engage with the clutch teeth 74 on the differential carrier 62. Therefore, the differential carrier 62 is coupled for rotation with the housing 52, thereby connecting the differential mechanism 38 to the power transmission mechanism 36.

[0076] focus on Figures 15 to 18B A fourth non-limiting embodiment of the disconnectable differential assembly 332 will now be described. Generally, the disconnectable differential assembly 332 is similar to the disconnectable differential assembly 232 (Figures 11 to 14), except that the housing unit 334 is now a two-piece combination of a stamped housing 336 and a hub 338, replacing the one-piece cast iron housing 52 with integral hubs 52C, 56B and broached splines 106. This two-piece housing configuration reduces weight. The stamped housing 336 is configured to include a cylindrical hub section 336A and an annular section 336B having a plurality of four (4) cutouts 340. The hub section 336A is formed to include an internal spline 342 ( Figure 18A Lugs 242 on the claw clutch ring 236 extend through the cutout 340, and the lug splines 246 engage with the housing splines 242 to further facilitate the rotation and axial movement of the claw clutch ring 336. Figure 18B The hub 338 is best illustrated, including a radial flange 350 located in and engaging with a central aperture 336C of the housing annular segment 336B. Although not limited thereto, a weld 352 (i.e., laser welding) is formed between the hub flange 350 and the housing annular segment 336B to rigidly secure the housing 336 to the hub 338 and establish a housing unit 334. As can be seen, the hub 338 is configured to provide a first boss 338A for mounting a bearing 58B thereon and a second boss 338B for mounting a bushing 90 thereon. Apart from the structural modifications described above, the function and operation of the disconnectable differential assembly 332 are the same as those described for the disconnectable differential assembly 232.

[0077] Now refer to the attached diagram. Figures 19 to 29 A fifth non-limiting embodiment of the disconnect differential assembly 432 will now be described.

[0078] Similarly, common reference numerals are used to identify components similar to those previously described. Typically, the disconnectable differential assembly 432 is configured with a modified clutch unit 434 and a modified clutch actuation unit 436, which, along with the disconnectable differential assembly 332 (see [reference]...) Figure 15 The two-piece housing unit 334 is used in combination. More specifically, the clutch unit 434 is shown as including a "stamped" claw-shaped plate ring 440 configured to include drive lugs 442 extending axially and radially from the disc plate 444. Each drive lug 442 defines a radially extending spline portion 442A and an axially extending claw portion 442B, which are stamped to extend between adjacent connecting sections 444A of the disc plate 444. The spline portion 442A of each lug 442 is configured to engage with an internal spline 342 in the hub section 336A of the housing 336. Thus, the claw-shaped plate ring 440 is configured to be rotary driven by the power transmission mechanism 36 while being axially sliding relative to the clutch teeth 74' formed on the face clutch plate 78' of the differential carrier 62 between a retracted position and an extended position.

[0079] The clutch actuation unit 436 is configured to connect to the claw-shaped clutch plate 440 for accompanying axial movement with the plunger 96 of the electromagnetic actuator unit 80. For this purpose, Figure 19 The diagram illustrates a first actuating plate 116 latching to a plunger 96, a modified second actuating plate 450 latching to a claw-shaped ring 440, and a thrust bearing 120 disposed between the first actuating plate 116 and the second actuating plate 450. The second actuating plate 450 has a plurality of four (4) latching tabs 452 extending axially from a ring section 454, and these latching tabs are oriented and aligned to extend through a cutout 340 in the housing 336. (See diagram from...) Figure 21 and Figures 26B to 26D As best seen, the latch tab 452 engages the portion of the disc plate 444 on the opposite side of the drive lug 442. The latch tab 452 is curled after the claw-shaped plate ring 440 is installed to establish a fixed connection therebetween.

[0080] When the electromagnetic clutch actuator unit 80 operates in its de-energized state, the disconnectable differential assembly 432 functions very similarly to the previously disclosed embodiment, wherein the claw-shaped plate ring 440 is normally in its retracted position and the plunger 96 is in its non-actuated position, thereby disconnecting the differential mechanism 38 from the power transmission mechanism 36 to establish a disconnected mode. Energization of the solenoid 92 moves the plunger 96 to its actuated position, causing the clutch actuator unit 436 to drive the claw-shaped plate ring 442 to its extended position, in which the claw-shaped portion 442B of the drive lug 442 engages with the clutch teeth 74' on the face clutch plate 78' to establish an engaged mode. Figure 28A non-contact position sensor 500 is illustrated, which is positioned and functionally operable to sense the axial position of the second actuator plate 118' for similarly sensing the position of the claw ring 440 in either its retracted or extended position. The position sensing signal is transmitted to a controller 44 for controlling the operation of the disconnectable differential assembly 432. Figure 29 The illustration shows the use of a contact position sensor 500' to engage the first actuator plate 116 (now including the radial extension) to again detect and signal the operating position of the claw clutch sleeve 100 associated with the disconnectable differential assembly 32.

[0081] Now refer to the attached diagram. Figures 30A to 39 A sixth non-limiting embodiment of the disconnectable differential assembly 532 will now be described. Typically, the disconnectable differential assembly 532 is configured to include: a modified clutch unit 534 and a clutch actuation unit 536, used in conjunction with a power transmission mechanism 36; a differential mechanism 38; and a two-piece housing unit 334'. The disconnect mechanism 40' is also slightly modified to include: an electromagnetic actuator unit 80' having a solenoid coil 90'; an annular clamshell-type core housing 94'; a plunger 96'; and an actuation sleeve 540 on which the plunger 96' is mounted. The free end of the actuation sleeve 540 maintains a constant but not fixed engagement with the first actuation plate 116A of the clutch actuation unit 536. A thrust bearing 120 is again disposed between the first actuation plate 116A and a partial actuation plate 118A. The second actuating plate 118A again includes a plurality of four (4) latching tabs 550 extending axially through a cutout 340' in the housing 334'.

[0082] Clutch unit 534 is now configured to include a claw-shaped clutch ring 560, such as Figure 33A and Figure 33B As best shown, the claw-shaped clutch ring 560 includes an outer radial spline 562, axial claw teeth 564, and a plurality of four guide lugs 566 with latching tabs 568. The outer spline 562 engages with an inner spline 342' within the housing 334', while the guide lugs 566 guide within a notch 340'. A latching tab 550 on the second actuating plate 118A engages with a latching tab 568 on the guide lugs 566, thereby responsively engaging the plunger 96' in its non-actuated position. Figure 31 ) and its actuation position ( Figure 32 The movement between ) is used to make the claw clutch ring 560 in its retracted position ( Figure 31 ) and its protruding position ( Figure 32The movement is between the clutch ring 560 and the face clutch tooth 74. The claw tooth 564 on the clutch ring 560 is shown as being displaced relative to the face clutch tooth 74 in the retracted position and engaging with it in the extended position. Figure 35 and Figure 36 The best illustration shows the “guiding” function provided by the guide lug 556 of the claw-shaped clutch ring 560, which extends through a similarly shaped cutout 340' in the housing 334', and the meshing engagement of the outer spline 562 with the inner spline 342'. Figure 37 A disconnectable differential assembly 532 is shown, with its solenoid unit 80' mounted in a housing 574 via a gasket 570 and a retaining ring 572. The housing 574 is associated with the entire assembled device, such as, for example, with a transmission housing or an axle housing.

[0083] Now refer to Figure 38 and Figure 39 The tapered feature associated with the plunger 96' of the electromagnetic actuator unit 80' for the disconnect differential assembly 532 is shown in more detail. Note that the front end portion 96A' is tapered, preferably tapering in the range of 4" to 10" relative to the overlapping portion of the core housing 94A'. Also note that the rear end portion 96B' of the plunger 96' engages with the radial flange portion 541 of the actuation sleeve 540.

[0084] Now refer to the attached diagram. Figure 40 A seventh non-limiting embodiment of the disconnectable differential assembly 632 will be described. Similarly, common reference numerals are used in these figures to identify components of the disconnectable differential assembly 632 that are structurally and / or functionally similar to those previously described as associated with the previously described disconnectable differential assemblies. More specifically, Figure 40 A power transmission mechanism 636 is shown, which is generally depicted as including a ring gear 650 and a bell-shaped housing 652 fixed to the ring gear 650 for rotation about a common axis "X". The ring gear 650 is adapted to be driven by the output gear 54 of the auxiliary electric motor 30. Figure 1 Driven by a ring gear 650 and a housing 652, a pair of laterally spaced cylindrical bosses 656A, 656B are defined on which a disconnectable differential assembly 632 is rotatably supported in a housing (not shown) via a pair of laterally spaced bearing assemblies 658A, 658B. An axial hub section 652A and a radial ring section 652B of the housing 652 mate with a plate portion 650A of the ring gear 650 to define an internal cavity 660 in which the differential mechanism 638 is supported for rotation about an "X" axis.

[0085] The differential mechanism 638 is shown as comprising: a differential carrier 662; a pair of differential portions 664 rotatably mounted on a pinion strut 666, the opposite ends of which are fixed in pole holes 668 formed in the differential carrier 662; and a pair of differential side gears 670, each meshing with one of the two differential pinions 664. As is conventional, each differential side gear 670 has an internal spline 672 configured to mesh with an external spline formed on the secondary drive shaft 34, thereby drivingly connecting the output of the differential mechanism 638 to the secondary wheel 18. The differential mechanism 638 is rotatably supported within an internal cavity 660 of the power transmission mechanism 636. Multiple axially extending clutch teeth 674 are formed on the outer end surface 676 of the differential carrier 662 to define a first clutch member configured as a face clutch 678.

[0086] The power-operated disconnect mechanism 640 is shown as generally comprising an electromagnetic actuator unit 680, a clutch unit 682, and a clutch actuation unit 684. The electromagnetic actuator unit 680 is annular in configuration and oriented around a central boss section 652C of the housing 652. The electromagnetic actuator unit 680 includes a solenoid 692, a clamshell-type pole or core housing 694 encapsulating and surrounding the solenoid 692, and a plunger 696 supported on the actuation sleeve 690 for axial sliding motion. In addition to the face clutch ring 678 on the differential carrier 662, the clutch unit 682 also includes a second clutch member shown as an adjustable clutch sleeve 600, configured to rotate with the housing 652 of the power transmission mechanism 636 and to move axially relative to the face clutch ring 678. The adjustable clutch sleeve may include a plurality of sector-shaped portions with external splines (e.g., similar to) formed on the outer surface 604 of the sleeve portion of the adjustable clutch sleeve 600. Figure 4 Furthermore, the axial section 652A of the housing 652 may include a plurality of internally splined sector portions for engaging with externally splined sector portions, thereby enabling the adjustable clutch sleeve 600 to rotate with the housing 652, but to move axially relative to the housing 652. Figures 30A to 39 Similar to the sixth embodiment, the adjustable clutch sleeve 600 may include a plurality of guide lugs that are guided within cutouts in the housing 652.

[0087] The clutch actuation unit 684 typically includes an application plate 616, a first actuation plate 618, a second actuation plate 619, a thrust bearing 620 located between the first actuation plate 618 and the second actuation plate 619, and a support plate 621. The application plate 616 engages the actuation sleeve 690. A biasing device (not shown) is configured to bias the adjustable clutch sleeve 600 to a disengaged position, in which the adjustable clutch sleeve 600 is spaced apart from the differential carrier 662. The support plate 621 is configured to engage and move the adjustable clutch sleeve 600 in response to associated movement of the application plate 616 and the actuation sleeve 690 / plunger 696. A connecting element 623 extends through and connects the support plate 621 and the clutch sleeve 600.

[0088] According to the preferred operating configuration, when the electromagnetic actuator unit 680 operates in the "de-energized" state, the disconnectable differential assembly 632 is generally capable of operating in the disconnected mode and can switch to the engaged mode in response to the electromagnetic actuator unit 680 being positioned in the "energized" state. More specifically, when the disconnected mode is established, the clutch unit 682 operates in the "released" state, and when the engaged mode is established, the clutch unit 682 operates in the "engaged" state. The release state of the clutch unit 682 is established when the biasing device positions the clutch sleeve 600 in the retracted position. In the retracted position, the claw teeth 612 of the clutch sleeve 600 disengage from engagement with the clutch teeth 674 on the face clutch plate 678. This axial movement of the adjustable clutch sleeve 600 to its retracted position forces the plunger 696 to move axially relative to the solenoid 692 to the unactuated position due to the interconnection established between them via the clutch actuator unit 684. With the claw-plate clutch sleeve 600 in its retracted position, the differential carrier 662 is not driven connected to the housing 652, thereby disconnecting the differential mechanism 38 from the power transmission mechanism 636. Therefore, no drive torque is transmitted from the auxiliary electric motor 630 to the second wheel 618 via the disconnectable differential assembly 632.

[0089] When torque needs to be transmitted from the auxiliary electric motor 630 to the second wheel 618, the disconnect differential assembly 632 is switched to its engaged mode by switching the electromagnetic actuator unit 680 to its energized state, thereby energizing the solenoid 692. The magnetic circuit generated when the solenoid 692 is energized causes the magnetic plunger 696 to move axially from its non-actuated position to its actuated position, which in turn causes the claw clutch sleeve 600 to move from its retracted position to its extended position, in which the claw teeth 612 of the claw clutch sleeve 600 engage with the clutch teeth 674 on the face clutch plate 678. This movement of the plunger 696 to its actuated position and the claw clutch sleeve 600 to its extended position due to the energization of the solenoid 692 is opposite to the bias applied thereto by the biasing element. With the claw-plate clutch sleeve 600 positioned and held in its extended position, the differential carrier 662 is driven to the housing 652, thereby connecting the differential mechanism 638 to the power transmission mechanism 636. Therefore, the drive torque generated by the auxiliary electric motor 630 is transmitted from the disconnectable differential assembly 632 to the auxiliary wheel 618 to establish a 4WD mode. Furthermore, when the auxiliary electric motor 630 is not transmitting torque via regenerative control associated with the control system 620, power regeneration can be controlled by switching the disconnectable differential assembly 632 to its engaged mode.

[0090] A contact position sensor 601 is positioned and functionally operable to sense the axial position of the application plate 616, for the same purpose of sensing the position of the adjustable clutch sleeve 600 in either its retracted or extended position. The position sensing signal is transmitted to a controller 620 for controlling the operation of the disconnectable differential assembly 632.

[0091] Now refer to the attached diagram. Figure 41An eighth non-limiting embodiment of the disconnectable differential assembly 732 will be described. Similarly, common reference numerals are used in these figures to identify components of the disconnectable differential assembly 732 that are structurally and / or functionally similar to those previously described as associated with previously described disconnectable differential assemblies. The disconnectable differential assembly 732 is similar to the seventh embodiment, but instead of including a contact position sensor positioned against an application plate, a contact sensor 701 engages a position sensor plate 703 located between the housing 752 and the contact sensor 701. A biasing element 705 biases the sensor plate 703 toward the contact sensor 701. The contact sensor 701 detects movement of the clutch sleeve 700 in response to the detection of associated movement of a translation plate 707 that moves with the clutch sleeve 700, and the translation plate 707 engages the position sensor plate 703. Furthermore, instead of engaging the application plate 616, the actuation sleeve 790 directly engages the thrust plate 721 to ultimately provide movement to the clutch sleeve 700. In addition, the translation plate 707 is located between the thrust plate 721 and the clutch sleeve 700, and extends across the housing 752 to engage with the position sensor plate 703.

[0092] Example embodiments of a disconnectable differential assembly of the type intended for use in electric vehicle powertrains are provided so that this disclosure will be thorough and will fully convey the scope to those skilled in the art. Numerous specific details, such as examples of particular components, devices, and methods, are set forth to provide a thorough understanding of embodiments of this disclosure. It will be apparent to those skilled in the art that specific details are not required, exemplary embodiments may be implemented in many different forms, and none should be construed as limiting the scope of this disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known techniques have not been described in detail.

[0093] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may also be intended to include the plural forms unless the context clearly indicates otherwise. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore specify the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein should not be construed as requiring them to be performed in the particular order discussed or described, unless specifically indicated as such. It should also be understood that additional or alternative steps may be employed.

[0094] When an element or layer is referred to as “on another element or layer,” “joined to,” “connected to,” or “linked to” another element or layer, the element or layer may be directly on, joined to, connected to, or linked to the other element or layer, or there may be intermediate elements or layers present. In contrast, when an element is referred to as “directly on another element or layer,” “directly joined to,” “directly connected to,” or “directly linked to” another element or layer, there may be no intermediate elements or layers present. Other terms used to describe relationships between elements (e.g., “between” vs. “directly between,” “adjacent” vs. “directly adjacent,” etc.) should be interpreted in the same manner. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0095] Although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or part from another region, layer, or part. Unless the context clearly indicates otherwise, terms such as “first,” “second,” and other numerical terms used herein do not imply any order or sequence. Therefore, a first element, component, region, layer, or segment discussed herein may be referred to as a second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0096] For ease of description, spatial relative terms such as “inside,” “outside,” “below,” “below,” “lower,” “above,” “upper,” etc., are used herein to describe the relationship between one element or feature as illustrated in the accompanying drawings and another element or feature (or other elements or features). Spatial relative terms may be intended to cover different orientations of the device in use or operation other than those depicted in the accompanying drawings. For example, if the device in the accompanying drawings is flipped, an element described as “below” or “below” other elements or features will be oriented “above” other elements or features. Thus, the example term “below” can cover both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein may be interpreted accordingly.

Claims

1. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; Wherein, the first clutch component is a face clutch having clutch teeth extending axially from the differential carrier; the second clutch component is a claw plate component connected to the housing via a splined connector and having a claw plate portion with axially extending claw teeth; and the clutch actuation mechanism includes: a first actuation plate latched to the actuation component; a second actuation plate having a tab extending through a cut in the housing and engaging the claw plate component; and a thrust bearing disposed between the first actuation plate and the second actuation plate.

2. The disconnectable differential assembly according to claim 1, wherein, The electromagnetic actuator unit is a ring device, which includes a ring solenoid coil encapsulated within a ring pole housing, and wherein the actuating component is a ring plunger configured to be in a non-actuated position when the solenoid coil is not energized, and in an actuated position when the solenoid coil is energized.

3. The disconnectable differential assembly according to claim 1, wherein, The second clutch component includes a plurality of spaced-apart segments with external splines, which continuously engage with a plurality of spaced-apart segments with internal splines formed in the housing and aligned with the cutout.

4. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; The first clutch component includes a radial clutch ring having clutch teeth extending radially outward from the differential carrier; the second clutch component is a radial clutch sleeve having a cylindrical sleeve portion connected to the housing via a splined connector and a claw-shaped ring portion having claw-shaped teeth extending radially inward from the sleeve portion; and the clutch actuation mechanism includes: a first actuating plate latched to the actuation component; a second actuating plate having a tab extending axially through a cut in the housing and engaging the sleeve portion of the radial clutch sleeve; and a thrust bearing disposed between the first actuating plate and the second actuating plate.

5. The disconnectable differential assembly according to claim 4, wherein, The sleeve portion of the radial clutch sleeve includes an external spline that continuously engages with an internal spline formed within the housing. The radial clutch ring is formed on the differential carrier, and the clutch teeth of the radial clutch ring define axially aligned first and second clutch teeth separated by toothless channels. Claw teeth are formed in the sleeve portion of the radial clutch sleeve, defining axially aligned first and second claw teeth separated by toothless clearances. When the radial clutch sleeve is in its retracted position, the first and second claw teeth disengage from their corresponding first and second clutch teeth, disengaging the differential carrier from the housing. When the radial clutch sleeve is in its extended position, the first and second claw teeth engage with their corresponding first and second clutch teeth; and / or The four sector-shaped portions of the external spline are formed on the outer surface of the sleeve portion of the radial clutch sleeve, and the four sector-shaped portions of the internal spline are formed on the inner surface of the outer casing, aligned with the cutout.

6. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; Wherein, the first clutch component is a face clutch formed on the differential carrier and having axially extending clutch teeth; wherein, the second clutch component is a claw-shaped plate ring having a claw-shaped plate portion with axially extending claw-shaped teeth, a plurality of drive lugs axially extending from the claw-shaped plate portion, and a latching flange extending from each of the drive lugs; wherein, the claw-shaped plate portion is located in the internal cavity, the drive lugs pass through a cut formed in the housing, and the latching flange extends to the outside of the housing; wherein, the clutch actuation mechanism includes: a first actuation plate latched to the actuation component; a second actuation plate latched to the latching flange of the claw-shaped plate ring; and a thrust bearing disposed between the first actuation plate and the second actuation plate.

7. The disconnectable differential assembly according to claim 6, wherein, The drive lug includes an external spline configured to continuously engage with an internal spline formed in the cutout of the housing.

8. The disconnectable differential assembly according to claim 6, wherein, The claw-shaped plate ring includes an external spline configured to continuously engage with an internal spline formed within the housing.

9. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; Wherein, the first clutch component is a face clutch associated with the differential carrier and having axially extending clutch teeth; wherein, the second clutch component is a claw-shaped plate ring having externally radially extending splines and axially extending claw teeth formed together on a drive portion connected by adjacent web portions; wherein, the clutch actuation mechanism includes: a first actuation plate latched to the actuation component; a second actuation plate having an axially extending drive flange passing through a cut formed in the housing and engaging with the web portion of the claw-shaped plate ring; and a thrust bearing disposed between the first actuation plate and the second actuation plate.

10. The disconnectable differential assembly according to claim 9, wherein, The external radial spline on the driving portion of the claw-shaped plate ring continuously engages with the internal spline formed in the internal cavity on the outer casing.

11. The disconnectable differential assembly according to claim 9, wherein, The drive flange on the second actuation plate includes a latching flange that is latched to the web portion of the claw-shaped plate ring via a coiled connector.

12. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; The electromagnetic actuator unit is a ring device, which includes a ring solenoid coil encapsulated in a ring pole housing. The actuating component is a ring plunger configured such that the plunger is in a non-actuated position when the solenoid coil is not energized, and in an actuated position when the solenoid coil is energized. The clutch actuation mechanism further includes an actuation sleeve, the annular plunger is mounted on the actuation sleeve, and a first actuation plate of the clutch actuation mechanism engages the end of the actuation sleeve. The clutch actuation mechanism further includes a second actuation plate and a thrust bearing disposed between the first actuation plate and the second actuation plate, wherein the second actuation plate is rotatable relative to the first actuation plate.

13. A disconnectable differential assembly for a vehicle, comprising: A power transmission mechanism, wherein the power transmission mechanism is driven by an electric motor; A differential mechanism, which is drivably connected to a pair of ground-engaging wheels; A power operation disconnection mechanism, which can operate in a disconnection mode to disconnect the power transmission mechanism from the differential mechanism, and in a connection mode to connect the power transmission mechanism to the differential mechanism. as well as A control system for controlling the operation of the electric motor and the power-operated disconnection mechanism; The power transmission mechanism includes a ring gear driven by the electric motor and an outer housing fixed to the ring gear to define an internal cavity. The differential mechanism is rotatably supported within the internal cavity and includes a differential carrier and a gear set driven by the differential carrier. The power-operated disconnection mechanism includes a clutch unit operably disposed between the outer housing and the differential carrier, and an electromagnetic actuator unit operable to switch the clutch unit between a released state establishing the disconnection mode and an engaged state establishing the connection mode. The clutch unit includes: a first clutch member associated with the differential carrier and having clutch teeth; and a second clutch member having claw teeth and configured to rotate with the housing and be axially movable relative to the differential carrier between a retracted position and an extended position. When the second clutch member is in the retracted position, the clutch unit is operable in the released state such that the claw teeth of the second clutch member disengage from the clutch teeth. When the second clutch member is in the extended position, the clutch unit is further operable in the engaged state such that the claw teeth of the second clutch member engage with the clutch teeth. The clutch unit also includes a biasing device for generally biasing the second clutch member toward the retracted position. A clutch actuation mechanism is operably arranged to interconnect a second clutch member with a movable actuating component of the electromagnetic actuator unit, wherein the actuating component is in a non-actuated position when the electromagnetic actuator unit is operated in a de-energized state, and in an actuated position when the electromagnetic actuator unit is operated in a energized state, and wherein the clutch actuation mechanism is operable to move the second clutch member between a retracted position and an extended position in response to movement of the actuating component between the non-actuated position and the actuated position of the actuating component; The electromagnetic actuator unit is a ring device, which includes a ring solenoid coil encapsulated in a ring pole housing. The actuating component is a ring plunger configured such that the plunger is in a non-actuated position when the solenoid coil is not energized, and in an actuated position when the solenoid coil is energized. The annular plunger has a tapered front outer surface configured to cover a non-tapered shoulder portion of the pole housing during movement of the annular plunger between its non-actuated and actuated positions.

14. The disconnectable differential assembly of claim 13, wherein, The electric motor and the disconnectable differential assembly define an electric drive axle for an electric vehicle.

15. The disconnectable differential assembly of claim 14, wherein, The second clutch component is a claw plate component, which includes a claw plate clutch sleeve having a cylindrical sleeve portion connected to the housing via a splined connector.

16. The disconnectable differential assembly of claim 13, wherein, The first clutch component is a face clutch, and the clutch actuation mechanism includes a second actuation plate. A biasing device is provided between the second actuation plate and the ring portion of the housing. The biasing device biases the claw-shaped plate ring away from the face clutch and biases the actuation component toward the non-actuated position of the actuation component via the clutch actuation unit.

17. The disconnectable differential assembly of claim 14, wherein, The electric drive axle is adapted to be installed as a secondary electric powertrain in an electric vehicle to provide four-wheel drive.

18. The disconnectable differential assembly of claim 16, wherein, The claw-shaped plate ring has a claw-shaped plate portion with axially extending claw-shaped teeth, a plurality of drive lugs extending axially from the claw-shaped plate portion, and a latching flange extending from each of the drive lugs. The second actuation plate includes a plurality of locking flanges that engage the drive lugs on opposite sides of the latching flanges. The biasing device biases the second actuation plate away from the ring portion of the housing, thereby biasing the claw-shaped plate ring away from the face clutch.

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