Two-way differential clutch for detecting disengagement

Abstract

A disconnecting differential assembly includes a housing configured to rotate about a first axis, a gear set having a first side gear and a second side gear, the gear set configured to transmit rotational power between the housing and the side gears, a first clutch element coupled to the first side gear to rotate therewith, a sleeve having an arcuate tab, a second clutch element coupled to the sleeve and facing the first clutch element, the sleeve and the second clutch element movable between a first position in which the clutch elements are spaced apart to rotationally decouple the first side gear from the sleeve, allowing relative rotation between the first side gear and the sleeve, and a second position in which the clutch elements are engaged to rotationally couple the first side gear to the sleeve, and a force plate configured to capture a coupling feature, wherein bidirectional axial movement of the force plate moves the sleeve and the second clutch element between the first position and the second position.

Description

Technical Field

[0001] This disclosure generally relates to axle assemblies, and more specifically to a two-way clutch used for detecting disengagement. Background Technology

[0002] This section provides background information relating to this disclosure, which is not necessarily prior art.

[0003] Vehicle drivetrains typically include one or more differentials configured to receive input torque and output differential torque to multiple vehicle wheels. A typical differential includes a differential housing, a pair of side gears, and a pair of output shafts. The differential housing is configured to receive input torque, and the pair of output shafts are non-rotatably coupled to a corresponding side gear and drivably connected to the corresponding vehicle wheel. Under certain conditions, the vehicle wheels typically driven by the differential do not require torque. In such conditions, a disconnect system can be used to interrupt torque transmission to the vehicle wheels. A disconnect system typically includes a disconnect clutch configured to either disconnect the differential housing from the torque supply source or disconnect one or more output shafts from the vehicle wheels. Typical plate applications only push to engage, but do not pull to disengage. Current methods involve actuators configured to push elements of the clutch engagement portion into the engaged state, but this method requires springs positioned between the clutch engagement portion elements to disengage when the actuator force is removed. During disengagement, the vehicle's intelligent system cannot confirm whether and / or when the clutch engagement components have disengaged by spring force.

[0004] While these constructions are intended for their intended purpose, there is a growing interest in obtaining definitive confirmation that the differential has been disconnected. Summary of the Invention

[0005] According to one embodiment, a disconnectable differential assembly is provided, comprising a differential housing and a differential gear set. The differential housing defines a cavity and is configured to rotate about a first axis. The differential gear set is received in the cavity and has a plurality of differential pinions, a first side gear, and a second side gear. The differential pinions are configured to transmit rotational power between the differential housing and the first and second side gears. The disconnectable differential assembly also includes a first clutch element, a sleeve, a second clutch element, and a force plate. The first clutch element is coupled to the first side gear to rotate with it. The sleeve is received in the differential housing and is rotatable relative to the differential housing. The sleeve has a coupling feature having an axially inner engagement surface and an axially outer engagement surface. A second clutch element is fixedly connected to a sleeve, wherein the second clutch element faces a first clutch element. The sleeve and the second clutch element are axially movable relative to the differential housing along a first axis between a first position and a second position. In the first position, the second clutch element is axially spaced from the first clutch element, thereby disengaging the first side gear from the sleeve and allowing relative rotation between them. In the second position, the second clutch element is engaged with the first clutch element, thereby rotatably engaging the first side gear with the sleeve. A force plate is axially movable along the first axis and configured to capture engagement features on the sleeve between an inner engagement surface and an outer engagement surface. The force plate is configured to move in both an axially inward and axially outward direction, thereby moving the sleeve and the second clutch element between the first and second positions.

[0006] In one embodiment, the first clutch element includes a first pawl, and the second clutch element includes a second pawl.

[0007] In another embodiment, the sleeve includes an annular hub portion and an annular disc portion, wherein the connecting feature includes an arcuate tongue extending circumferentially at the radially outermost portion of the annular disc portion, the arcuate tongue having an axially inner engagement surface and an axially outer engagement surface. The load-bearing plate includes an annular ring having a radially inwardly opening arcuate groove, wherein the arcuate tongue is received within the arcuate groove. The tongue and groove are configured in size and shape to allow relative rotation between the tongue and groove while the load-bearing plate and the sleeve are constrained to move axially together. Attached Figure Description

[0008] The accompanying drawings described herein are for illustrative purposes only and not for all possible implementations, and are not intended to limit the scope of this disclosure.

[0009] Figure 1This is a schematic diagram of a vehicle having a front axle assembly having an exemplary disconnectable differential assembly constructed in accordance with the teachings of this disclosure; Figure 2 yes Figure 1 A partial isometric sectional view of the front axle assembly; Figure 3 In one implementation method Figure 1 and Figure 2 An isometric view of an exemplary disconnectable differential assembly; Figure 4 From Figure 3 An isometric exploded assembly view of the disconnected differential assembly as seen from the left-hand side; Figure 5 From Figure 3 Isometric exploded assembly view of the disconnected differential assembly as seen from the right side; Figure 6 It shows in more detail Figure 4 Isometric view of the clutch section of the disconnect differential assembly; Figure 7 It shows in more detail Figure 6 Isometric view of the load-bearing plate section; Figure 8 It is along Figure 3 A front view of the disconnected differential assembly observed along line 8-8; Figure 9 It is basically along Figure 8 A cross-sectional view of the disconnected differential assembly taken from line 9-9; Figure 10 It is basically along Figure 8 A cross-sectional view of the disconnected differential assembly taken from line 10-10; Figure 11 It shows in more detail Figure 4 An isometric view of a portion of the thrust component; Figure 12 It is basically along Figure 8 A cross-sectional view of the disconnected differential assembly taken from line 12-12; and Figure 13 It is the disconnect differential assembly in Figure 12 An enlarged sectional view of a portion of the middle section, which is basically surrounded by line 13-13.

[0010] Throughout the various views in the accompanying drawings, corresponding reference numerals denote the corresponding components. Detailed Implementation

[0011] Figure 1This is a schematic diagram of an exemplary vehicle 20 in which a disconnectable differential assembly with a two-way differential clutch for detecting disengagement may be used. Vehicle 20 includes a front axle assembly 22, which is shown as having a disconnectable differential assembly 24 constructed according to the teachings of this disclosure. Vehicle 20 is shown as a four-wheel drive vehicle 20; however, it should be understood that the disconnectable differential assembly 24 described herein can be used in other types of vehicles, such as front-wheel drive vehicles, rear-wheel drive vehicles, or all-wheel drive vehicles.

[0012] Vehicle 20 includes a control system 26, a powertrain 28, a front axle assembly 22, and a rear axle assembly 38. The powertrain 28 has an engine 30 and a transmission 32, which provide rotational power to a transmission system 34, which has a transfer case 36. Rotational power can be transmitted from the transfer case 36 to the front axle assembly 22 and the rear axle assembly 38 via a front driveshaft 40 and a rear driveshaft 42, respectively. The front axle assembly 22 can be configured to drive a set of front wheels 44.

[0013] The rear axle assembly 38 can be configured to drive a set of rear wheels 46. The configuration of the rear axle assembly 46 can be generally similar to that of the front axle assembly 22, and thus, the description of the front axle assembly 22 will not be repeated for the rear axle assembly 38 (i.e., the rear axle assembly 38 can be configured to have a disconnect differential assembly similar to the disconnect differential assembly 24 described herein). It should be understood that other configurations can be used; for example, the front axle assembly 22 may include the disconnect differential assembly 24, while the rear axle assembly 38 can be configured differently, or may not include the disconnect differential assembly. In another embodiment, the rear axle assembly 38 may include a disconnect differential assembly similar to the disconnect differential assembly 24, while the front axle assembly 22 does not include the disconnect differential assembly 24.

[0014] In the illustrated embodiment, the control system 26 may include an electronic control module 48. The control module 48 may be any suitable type of electronic controller configured to control the operation of the disconnect differential assembly 24 as described herein. The disconnect differential assembly 24 may be electrically connected to the control module 48.

[0015] Figure 2 In one implementation method Figure 1 A partial isometric sectional view of the front axle assembly 22. The front axle assembly 22 is shown as including an axle housing assembly 50, an input pinion 52, a ring gear 54, a disconnectable differential assembly 24, and a pair of half-shafts or output shafts 56, 58. The axle housing assembly 50 has a carrier housing 60 and a pair of half-shaft sleeves 62 connected to the carrier housing 60. The carrier housing 60 defines a cavity 64 in which the disconnectable differential assembly 24 is received.

[0016] Each of the output shafts 56 and 58 can be received coaxially through a corresponding one of the half-shaft sleeves 62. The output shafts 56 and 58 can extend into the housing 64 and be driven to the disconnect differential assembly 24 to receive rotational power. Each output shaft 56 and 58 can be driven to one of the front wheels 44.

[0017] Input pinion 52 can be mounted to the housing 60 to rotate about a first axis 66. Input pinion 52 can be coupled to rotate with the front drive shaft 40 and may include pinion 68, which can be disposed in a cavity 64. Gear ring 54 can be received in the cavity 64 and is rotatable about a second axis 70, which may be transverse to or substantially perpendicular to the first axis 66. Gear ring 54 can meshily engage with pinion 68.

[0018] Figure 3 This is an isometric view of a disconnectable differential assembly 24 in one embodiment. Assembly 24 includes a differential housing 72. The differential housing 72 can be mounted to an axle housing assembly 50 to rotate about a second axis 70, which can be transverse to or perpendicular to a first axis 66. The second axis 70 may be referred to herein as the differential axis 70. The differential housing 72 can be formed as one or more discrete components, such as a first housing member 74 and a second housing member 76. In the illustrated embodiment, the first housing member 74 and the second housing member 76 can define a differential cavity 78. In the specific example provided, the first housing member 74 and the second housing member 76 can be bolted or welded to each other and bolted or welded to a gear ring 54. The differential housing 72 constitutes a differential input section. The differential assembly 24 also includes an electrical connector 80 configured to be electrically connected to a control module 48 to implement the operational functions described herein.

[0019] Figure 4 From Figure 3 An isometric exploded assembly view of the disconnected differential assembly 24, viewed from the left-hand side. Figure 5 From Figure 3 An isometric exploded assembly view of assembly 24, viewed from the right-hand side. The disconnectable differential assembly 24 includes a differential housing 72 (…). Figure 4 The first housing component 74 and the second housing component 76), the differential gear set 82, and the clutch 84, the clutch 84 including an actuator 86 coupled with an electromagnetic solenoid 88.

[0020] The differential gear set 82 is received within the differential housing 78 and can be of any type. This gear set receives rotational power from the differential housing 72, which serves as the differential input, and outputs the rotational power to the output shafts 56, 58. In one embodiment, the differential housing 72 and the differential gear set 82 together constitute the differential mechanism. In the specific example provided, the differential gear set 82 may include a bevel gear arrangement, such as two or more small bevel gears 90 (i.e., differential pinions 90), which mesh with a first (conical) side gear 92 and a second (conical) side gear 94. However, it should be understood that, alternatively, other types of gear arrangements, such as spur gear arrangements or helical gear arrangements, may be used. In this arrangement, the differential gear set 82 is configured to transmit rotational power between the differential housing 72 and the first side gear 92 and the second side gear 94. The first side gear 92 and the second side gear 94 may also be referred to as the first differential output gear 92 and the second differential output gear 94.

[0021] The first side gear 92 and the second side gear 94 are rotatable about the second axis 70 relative to each other and relative to the differential housing 72. A bearing or washer 96 may be disposed on the first side 98 of the first side gear 92. In the provided example, the washer 96 is a flat annular thrust washer coaxial with the second axis 70, but other configurations may also be used. Bearing or washer 100 ( Figure 5 It can be set on one side of the second side gear 94.

[0022] The first side gear 92 can rotate relative to the output shafts 56 and 58. The first side gear 92 can be rotated via gear 102 ( Figure 5 The second side gear 94 engages meshingly with two pinions 90. The second side gear 94 can be drivenly coupled to the output shaft 56 in a conventional manner. In the provided example, the second side gear 94 has a set of internal splines 104 disposed around the second axis 70 and around the interior of the second side gear 94. The internal splines 104 meshingly engage with mating external splines 106 formed on the outer surface of the output shaft 56. The second side gear 94 can engage meshingly with two pinions 90.

[0023] In the illustrated embodiment, a pinion 90 is mounted within a differential housing 78 to a center pin 108, which is coupled to a differential housing 72 and is transverse to or perpendicular to the second axis 70. The pinion 90 is mounted to the center pin 108 to be rotatable about the center pin 108 relative to the differential housing 72 and to rotate together with the differential housing 72 about the second axis 70. A bearing or washer 110 may be disposed between each pinion 90 and the differential housing 72. In the provided example, the washer 110 is an annular truncated conical thrust washer coaxial with the center pin 108, but other configurations may also be used.

[0024] Assembly 24 also includes a force plate 112—shown as two parts 1121 and 1122, a displacement sleeve 114 (sometimes referred to as sleeve 114 below), a thrust member 116, a plunger 118, a coil housing 120—shown as two parts 1201 and 1202, and a retaining ring 122.

[0025] Figure 6 yes Figure 4 A portion of the isometric view, Figure 6 Some features of the clutch 84 are shown in more detail. The clutch 84 is functionally configured to switch the disconnectable differential assembly 24 between a first disengagement operating mode and a second engagement operating mode. In the first disengagement operating mode, the first side gear 92 is rotatably disengaged from the output shaft 58, and in the second engagement operating mode, the first side gear 92 operates to drive the output shaft 58. The clutch 84 may include a first clutch element or first pawl 124, a second clutch element or second pawl 126, a force plate 112, and an actuator 86. The first clutch element or first pawl 124 faces the second clutch element or second pawl 126 axially.

[0026] The first claw 124 can be fixedly connected to the first side gear 92 to rotate together with the first side gear 92, and can be disposed on one side 98 of the first side gear 92. This side 98 is axially opposite to the side on which the teeth 102 are disposed. In other words, this side 98 is the axial side facing the axially outward direction 130. Direction 132 is the axially inward direction. In the illustrated embodiment, the first claw 124 has a generally annular shape, which is coaxial with the second axis 70. The first claw 124 may include a plurality of first engagement features 128 which can be circumferentially disposed around the second axis 70. The first claw 124 can be integral with the first side gear 92.

[0027] In one embodiment, the first engagement feature 128 is a protrusion or claw that is circumferentially spaced around the second axis 70 and extends axially outward in a direction 130 from a generally flat surface 98. The first engagement feature 128 is located radially outward of the output shafts 56, 58, which are received in the central holes of the first side gear 92 and the second side gear 94. A washer 96 is disposed radially outward of the first engagement feature 128 and may contact the surface / side 98 to allow relative rotation between the first claw 128 and the force plate 112.

[0028] The shift sleeve 114 is received in the differential housing 72 and is rotatable relative to the differential housing 72. In one embodiment, the shift sleeve 114 may be coaxially disposed about a second axis 70 and disposed within the differential cavity 72. The shift sleeve 114 has an annular hub portion 134 and an annular disc portion 136. The annular disc portion 136 includes a second claw 126. In one embodiment, the hub portion 134 may be fixedly coupled to the annular disc portion 136, and therefore also fixedly coupled to the second claw 126.

[0029] The shift sleeve 114 includes a central bore extending through the annular hub portion 134 and through the annular disc portion 136, and defines a plurality of internal splines 138 that mate with a plurality of external splines 140 defined on the outer surface of the output shaft 58 and at the end of the output shaft 58. The second claw 126 may include a plurality of second engagement features 142 (see also...). Figure 5 These second engagement features 142 are configured to engage the first engagement feature 128 when the second claw 126 is in a second position (e.g., a connected position). The second engagement features 142 may be located on the annular disc portion 136, radially outward of the annular hub portion 134. The number of second engagement features 142 may be equal to the number of first engagement features 128. In one embodiment, the second engagement features 142 are two opposite axial sides 144 and 146 extending through the second claw 126. Figure 5 The first engagement feature 128 (e.g., a protrusion or claw tooth) is received into the second engagement feature 142 (e.g., a hole) when the second claw 126 is in the second position (e.g., the connected position) to engage the first claw 124 and the second claw 126 to achieve co-rotation. When the shift sleeve 114 is in the second position, the output shaft 58 and the first side gear 92 rotate together.

[0030] The displacement sleeve 114 includes a coupling feature 148 configured to be captured by a force plate 112. This capture allows the force plate 112 to pull the displacement sleeve 114 in an axially outward direction 130 and push the sleeve 114 in an axially inward direction 132 by axial movement. Pushing the displacement sleeve 114 toward the first side gear 92 engages the first claw 124 and the second claw 126, while pulling the displacement sleeve 114 away from the first side gear 92 disengages the first claw 124 and the second claw 126. In one embodiment, the coupling feature 148 includes an arcuate tongue 148 extending circumferentially at the radially outermost portion of the annular disk portion 136. In another embodiment, the tongue extends 360 degrees around the periphery of the annular disk portion 136. The connection feature 148 has a first engagement surface 150 and a second engagement surface 152 facing the axially outward direction 130 and the axially inward direction 132, respectively (best shown in...). Figure 13 middle).

[0031] Continue to refer to Figure 6 The load-bearing plate 112 includes a first portion 1121 and a second portion 1122, which form an annular ring after the two portions are mounted onto the tongue 148 around the entire periphery of the annular disk portion 136. The two portions 1121 and 1122 may be identical in construction. The load-bearing plate 112 is axially movable along the second axis 70.

[0032] Figure 7 yes Figure 6 An enlarged isometric view of the load-bearing plate 1122. Each of the load-bearing plates 1121 and 1122 has a generally U-shaped body defining a radially inwardly opening arcuate groove 154, wherein the body includes a pair of legs 156, 158 and a connecting bridge 160. An arcuate tongue 148 is received in the arcuate groove 154. The tongue 148 and the groove 154 are configured in size and shape to allow relative rotation about axis 70 to occur between them. Furthermore, at least because the tongue 148 is received in the groove 154, the load-bearing plate 112 and the displacement sleeve 114 can move and are constrained to move axially together in both the axially outward direction 130 and the axially inward direction 132 (i.e., bidirectionally).

[0033] Each load-bearing plate portion (e.g., portions 1121 and 1122) has a first connecting structure 162 and a second connecting structure 164, the second connecting structure 164 being complementary to the first connecting structure 162, which allows the arcuate portions 1121 and 1122 to be fixedly connected to each other to form an annular load-bearing plate 112. The first connecting structure 162 includes an inner protrusion 166 and an outer blind hole 168. The second connecting structure 164 includes an inner blind hole 170 and an outer protrusion 172. The first connecting structure 162 is disposed at a first free end of the arcuate portion 1122, while the second connecting structure 164 is disposed at the opposite second free end of the arcuate portion 1122. The grooves 154 of portions 1121 and 1122 are fitted onto the tab 148 of the sleeve 114, wherein the first connecting feature 162 on portion 1121 mates with the second connecting feature 164 on portion 1122, and the second connecting feature 164 on portion 1121 mates with the first connecting feature on portion 1122. After assembly, the tab 148 is received in the groove 154.

[0034] The load-bearing plate 112 also includes a plurality of circumferentially arranged posts 174 extending axially in an axially outward direction 130. Each post 174 includes a connecting protrusion 176 extending in a generally radially outward direction. The connecting protrusion 176 is configured to securely connect the load-bearing plate 112 to the thrust member 116.

[0035] Figure 8 It is basically along Figure 3 The front view of the disconnected differential assembly 24, observed along line 8-8. Figure 8 for Figure 9 , Figure 10 and Figure 12 The sectional view provides a reference frame.

[0036] Figure 9 It is basically along Figure 8 The image shows a cross-sectional view of the disconnected differential assembly 24 taken by line 9-9. The cavity 78 of the second housing member 76 includes a stepped profile comprising a first outer surface 76a, a first circumferential surface 76b, a second outer surface 76c, a second circumferential surface 76d, and a third outer surface 76e.

[0037] Internal spline 138 and external spline 140 connect the shift sleeve 114 and the second claw 126 to the output shaft 58 for rotation with the output shaft 58, while allowing the shift sleeve 114 and the second claw 126 to translate axially relative to the output shaft 58. Therefore, the second claw 126 can translate relative to the output shaft 58 between a first position (e.g., a disconnected or disengaged position) and a second position (e.g., a connected or engaged position). In the illustrated embodiment, the shift sleeve 114 and the second claw 126 have been moved to the second position by the actuator 86, in which the second claw 126 engages with the first claw 124 to rotatably engage the first side gear 92 with the shift sleeve 114. Since the output shaft 58 is splined to the sleeve 114, in the second position of the shift sleeve 114, the output shaft 58 is rotatably engaged with the first side gear 92. The first engagement feature 128 engages with the second engagement feature 142, as shown in the hidden line format.

[0038] Figure 10 It is basically along Figure 8 The image shows a cross-sectional view of the disconnected differential assembly 24 taken along line 10-10. In the illustrated embodiment, the shift sleeve 114 is in a second position, designated 1142, in which the first engagement feature 128 engages with the second engagement feature 142.

[0039] The shift sleeve 114 and the second pawl 126 are axially movable relative to the differential housing 72 along the second axis 70 to a first position. In the illustrated embodiment, the shift sleeve 114 is also shown in dashed form and is designated 1141. In the first position, the shift sleeve 114 and the second pawl 126 (i.e., the second clutch element) are spaced apart from the first pawl 124 (i.e., the first clutch element) along the second axis 70 by at least a first predetermined interval distance, such that the first engagement feature 128 does not engage with the second engagement feature 142. Therefore, the first pawl 124 and the second pawl 126 are disengaged. This disengagement allows relative rotation between the first pawl 124 (and therefore the first side gear 92) and the second pawl 126 (and therefore the shift sleeve 114), such that the sleeve 114 and its associated output shaft 58 are rotatably disconnected from the first side gear 92. In one embodiment, the first predetermined interval distance when the sleeve 114 is in the first position is greater than the second predetermined interval distance when the sleeve 114 is in the second clutch engaged position. The axial movement of the displacement sleeve 114 to the first position and the second position, and the axial movement between the first position and the second position, is achieved by using the bidirectional force plate 112 as described herein.

[0040] Back Figure 4 The thrust member 116 includes a plate portion 178 and a plurality of connecting legs 180 extending axially in an axially inward direction 132. Each of the plurality of connecting legs 180 aligns with and extends into a corresponding hole 182 in the second housing member 76. Furthermore, each of the plurality of legs 180 includes a groove 184 for securing the thrust member 116 to the load-bearing plate 112. The thrust member 116 also includes a plurality of coupling members 186. The coupling members 186 are configured to engage a plunger 118 to the thrust member 116 such that the plunger 118 and the thrust member 116 move axially together, while allowing relative rotational motion relative to the second axis 70.

[0041] Figure 11 yes Figure 4 An enlarged isometric view of the thrust member 116. Figure 11The leg 180, slot 184, and connecting member 186 are shown in more detail. Each slot 184 may be generally rectangular in shape, as shown, but will complement and mate with the connecting protrusion 176 for connecting the thrust member 116 to the load-bearing plate 112. Each connecting member 186 includes a pair of hangers 188 extending radially inward from the plate portion 178. Each of the connecting members 186 also includes a planar plate platform 190 and a retaining lip 192 located axially outward of the plate portion 178. The connecting member 186 defines a generally J-shaped channel configured in size and shape to receive the radially innermost edge of the plunger 118.

[0042] Figure 12 It is basically along Figure 8 The image shows a cross-sectional view of the disconnected differential assembly 24 taken along line 12-12. In the illustrated embodiment, the shift sleeve 114 is in the second engaged position. Figure 12 In particular, the arcuate groove 154 captures the arcuate tongue 148 to allow bidirectional movement of the displacement sleeve 114.

[0043] Figure 13 yes Figure 12 An enlarged view of the area enclosed by the line marked 13-13. Figure 13 The sleeve 114 is shown with an annular disc portion 136 including an arcuate tongue 148, a hole 182 through the housing 72, a post 174 of the force plate 112 positioned in the hole 182, a leg 180 of the thrust member 116 also positioned in the hole 182, and a plunger 118.

[0044] The arcuate groove 154 captures the protruding tongue 148, particularly the first engagement surface 150 and the second engagement surface 152 of the protruding tongue 148. Each of the posts 174 of the load-bearing plate 112 is aligned with a corresponding hole in the bore 182 and extends from the cavity 78 of the differential housing 72 into the corresponding hole in the axially outward direction 130. A connecting protrusion 176 of the post 174 is provided in the groove 184 to securely connect the thrust member 116 to the load-bearing plate 112. Thus, the thrust member 116—particularly the plate portion 178—is axially spaced from the load-bearing plate 112. Furthermore, through the connection of the protrusion 176 with the groove 184, the load-bearing plate 114 and the thrust member 116 rotate together with the differential housing 72. The bore 182 is sized and shaped to allow the posts 174 and the legs 180 to move axially through the bore 182 without interference. Therefore, the thrust member 116, the force plate 112, and the displacement sleeve 114 (through the connection between the force plate and the sleeve) can move and are constrained to move axially together in both the axially outward direction 130 and the axially inward direction 132.

[0045] The connecting protrusion 176 is shown to be received in the groove 184 to connect the force plate 112 to the thrust member 116. Figure 13 It is also shown that the radial innermost edge of the plunger 118 is seated in the coupling member 186, which connects the plunger 118 to the thrust member 116.

[0046] The force plate 112 is configured to capture the tongue 148 in such a way that the force plate 112 can push the shift sleeve 114 to a second engaged position in the axially inward direction and pull the shift sleeve 114 to a first disengaged position in the axially outward direction, and push and pull the shift sleeve 114 between the first disengaged position and the second engaged position. In one embodiment, this arrangement allows the shift sleeve 114 to be pulled out of the engaged state to disengage the differential assembly 24. This arrangement allows for the definitive detection of when disengagement occurs, thereby detecting when the differential assembly is disengaged. This arrangement represents an improvement over a disengaged differential assembly that uses a spring to bias the clutch from the engaged state to the disengaged position. In one embodiment, the disengagement of the differential assembly can be definitively detected due to the definitive, controlled pulling action applied to the sleeve 114.

[0047] Refer again Figure 4 Actuator 86 is configured to move the force plate 112 axially and bidirectionally, and thereby also move the displacement sleeve 114 having the second claw 126 axially and bidirectionally, causing the displacement sleeve 114 to move between a first disconnected position and a second connected position. Actuator 86 can be any type of device or linear motor that can be employed to selectively, bidirectionally, and axially translate the sleeve / second claw 126 along the second axis 70 to engage and disengage with the first claw 124. In the illustrated embodiment, actuator 86 includes an electrically operated actuator comprising an electromagnetic solenoid 88. In alternative configurations not specifically shown, actuator 86 can be another type of linear motor, such as a hydraulic linear motor, a mechanical linear motor, or an electromechanical linear motor (e.g., a hydraulic cylinder, ball ramp, screw drive, etc.), for selectively axially translating the force plate 112, displacement sleeve 114, and second claw 126 along the second axis 70.

[0048] The solenoid 88 can be mounted on the differential housing 72 in such a way that the differential housing 72 is allowed to rotate relative to the solenoid 88, but the solenoid 88 is restricted to axial movement along the second axis 70 in a direction away from the second claw 126. In other words, the solenoid 88 can be axially fixed relative to the differential housing 72, but the differential housing 72 can rotate relative to the solenoid 88 about the second axis 70.

[0049] Solenoid 88 may include housing 120 (parts 1201 and 1202), electromagnetic coil 194 ( Figure 10 ) and plunger 118. The electromagnetic coil 194 may be located on and / or adjacent to the housing 120, which in the illustrated embodiment approximates a spool. The plunger 118 may include a plurality of rods 196; in one embodiment, four rods 196 are present—in Figure 4 Two of them are shown. The plunger 118 also includes a notch 198 that provides clearance for receiving the connector 80 as the plunger 118 moves in both axially outward and axially inward directions. The housing portion 1202 includes cutouts 200 that are aligned with the rod 196 and sized to allow the rod 196 to axially pass through the cutouts 200 during plunger 118 movement. A retaining ring 122 may be disposed around an annular portion of the second housing member 76 and can be securely coupled to this annular portion to prevent axially outward movement of the solenoid 88.

[0050] The plunger 118 can selectively move along the second axis 70 in response to an excitation control signal applied to the solenoid coil 194 by the control module 48. In this respect, the solenoid coil 194 can be electrically connected to the control module 48 for operation controlled by the control module 48. The control module 48 can control when and how the solenoid coil 194 is energized (i.e., when and how current flows through the solenoid coil 194). When the solenoid 88 is thus activated, the solenoid coil 194 generates a predetermined magnetic field (not shown) that causes the plunger 118 to move axially, thereby moving the displacement sleeve 114 to the aforementioned first and second positions and between the aforementioned first and second positions.

[0051] Therefore, the disconnectable differential assembly 24 can operate in a first mode, in which the actuator 86 is controlled by the control module 48 to move the plunger 118 axially away from the second housing member 76 in an axially outward direction. The movement of the plunger 118 causes the thrust member 116 and the force plate 112 to move axially in the same axial direction. In this first mode, the movement of the force plate 112 operates by pulling the displacement sleeve 114 and the second pawl 126 away from the first pawl 124 to a first position (i.e., the differential disconnect position). In the first position, the first engagement feature 128 disengages from the second engagement feature 142, wherein the first side gear 92 is allowed to rotate relative to the differential housing 72 and relative to the second pawl 126. Since the first side gear 92 rotates freely and the disconnectable differential assembly 24 is an open differential, torque is not transmitted to either of the output shafts 56, 58.

[0052] The disconnectable differential assembly 24 can also operate in a second mode, in which the actuator 86 is controlled by the control module 48 to move the plunger 118 axially toward the second housing member 76 in an axially inward direction. The movement of the plunger 118 causes the thrust member 116 and the force plate 112 to move axially in the same axial direction. In this second mode, the movement of the force plate 112 operates by pushing the shift sleeve 114 and the second pawl 126 toward the first pawl 124 to a second position (i.e., the differential engagement position). In the second position, the first engagement feature 128 engages with the second engagement feature 142, wherein the first side gear 92 is locked to the output shaft 58 for common rotation. Therefore, the disconnectable differential assembly 24 operates as an open differential to allow differential torque to be output between the output shafts 56, 58.

[0053] The foregoing description of the embodiments is provided for purposes of illustration and description. It is not intended to be exhaustive or limiting of this disclosure. Even if not specifically shown or described, various elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable and can be used in selected embodiments where applicable. The same elements or features may also be varied in many ways. These variations should not be considered as a departure from this disclosure, and all such modifications are intended to be included within the scope of this disclosure.

Claims

1. A disconnectable differential assembly, the disconnectable differential assembly comprising: A differential housing defining a cavity, the differential housing being configured to rotate about a first axis; A differential gear set, wherein the differential gear set is received in the cavity in the differential housing, the differential gear set having a plurality of differential pinions and a first side gear and a second side gear, the differential pinions being configured to transmit rotational power between the differential housing and the first side gear and the second side gear; A first clutch element is connected to a first side gear to rotate together with the first side gear; A sleeve, the sleeve being received in the differential housing and rotatable relative to the differential housing, the sleeve having a coupling feature having a first engagement surface and a second engagement surface; A second clutch element, fixedly coupled to the sleeve, wherein the second clutch element faces the first clutch element, wherein the sleeve and the second clutch element are axially movable relative to the differential housing along a first axis between a first position and a second position. In the first position, the second clutch element is axially spaced from the first clutch element, thereby rotatably disengaging the first side gear from the sleeve and allowing relative rotation between the first side gear and the sleeve. In the second position, the second clutch element engages with the first clutch element, thereby rotatably engaging the first side gear with the sleeve. A force-bearing plate, which is axially movable along the first axis and configured to capture the engagement feature on the sleeve between the first engagement surface and the second engagement surface, wherein the force-bearing plate is configured to move in both an axially inward direction and an axially outward direction, thereby moving the sleeve and the second clutch element between the first position and the second position.

2. The disconnectable differential assembly according to claim 1, wherein, The first clutch element includes a first pawl, and the second clutch element includes a second pawl.

3. The disconnectable differential assembly according to claim 1, wherein, The sleeve includes an annular hub portion and an annular disk portion, wherein the connecting feature includes an arcuate tongue extending circumferentially at the radially outermost portion of the annular disk portion, the arcuate tongue having a first engagement surface and a second engagement surface.

4. The disconnectable differential assembly according to claim 3, wherein, The force-bearing plate includes an annular ring having a radially inwardly open arcuate groove, wherein an arcuate tongue is received in the arcuate groove, and both the tongue and the groove are configured in size and shape to allow relative rotation between the tongue and the groove while the force-bearing plate moves axially together with the sleeve.

5. The disconnectable differential assembly according to claim 4, wherein, The ring includes multiple arc-shaped portions, each of which has a first connecting structure and a second connecting structure, the second connecting structure being complementary to the first connecting structure, which allows the arc-shaped portions to be connected to each other to form the ring.

6. The disconnectable differential assembly according to claim 5, wherein, The first connecting structure includes a first protrusion and a first blind hole at a first free end of the arcuate portion, wherein the first protrusion is located inside the first blind hole, and wherein the second connecting structure includes a second blind hole and a second protrusion at a second free end opposite to the arcuate portion, wherein the second blind hole is located inside the second protrusion.

7. The disconnectable differential assembly according to claim 4, wherein, The force-bearing plate includes a plurality of columns arranged circumferentially, wherein each of the columns extends axially in the outward direction of the axial direction. The force-bearing plate also includes a thrust member having a plate portion and a plurality of legs extending axially from the plate portion in the inward direction of the axial direction. The plurality of columns are aligned with and fixedly engaged with the plurality of legs to fix the thrust member to the annular ring, wherein the plate portion and the annular ring are spaced apart axially.

8. The disconnectable differential assembly of claim 1, further comprising an actuator configured to axially move the force plate to move the sleeve and the second clutch element between the first position and the second position, wherein, The actuator further includes an electromagnetic solenoid and a plunger, wherein the plunger is connected between the solenoid and the thrust member.

9. The disconnectable differential assembly of claim 1, further comprising a position sensor configured to at least determine when the sleeve and the second clutch element are in the first position, in which the first side gear is rotatably disengaged from the sleeve.

10. The disconnectable differential assembly according to claim 2, wherein, The first claw includes a plurality of first engagement features, wherein the second claw includes a plurality of second engagement features, and wherein the first engagement features include a plurality of protrusions circumferentially spaced around the first axis and extending from a first axial side of the first claw in an axially outward direction, the first axial side being opposite to the first side gear, and wherein the second engagement features include a plurality of holes or recesses circumferentially spaced around the first axis, each of the holes or recesses being configured to receive a corresponding protrusion when the sleeve and the second claw are in the second position.

11. The disconnectable differential assembly according to claim 1, wherein the disconnectable differential assembly further comprises: An axle housing, wherein the differential housing is received within the axle housing, the axle housing supporting the differential housing for rotation of the differential housing about the first axis; A gear ring, which is connected to the differential housing to rotate together about the first axis; An input pinion, supported by the axle housing for rotation about a second axis, engages meshingly with the gear ring.

12. The disconnectable differential assembly according to claim 1, wherein, One of the first mating surface and the second mating surface faces the axial outward direction, and the other of the first mating surface and the second mating surface faces the axial inward direction.

13. A disconnectable differential assembly, the disconnectable differential assembly comprising: A differential mechanism having a differential input section and a differential gear set, the differential input section being rotatable about a differential axis, the differential gear set having a first differential output gear and a second differential output gear, the first differential output gear and the second differential output gear being rotatable relative to the differential input section about the differential axis, the differential gear set being configured to transmit rotational power between the differential input section and the first differential output gear and the second differential output gear; A sleeve, the sleeve being rotatable relative to the differential input portion about the differential axis and being axially movable along the differential axis; The clutch has a first clutch element and a second clutch element, the first clutch element being fixedly connected to a first differential output gear, and the second clutch element being fixedly connected to a sleeve. The clutch is operable in a disengaged mode and an engaged mode. In the disengaged mode, the sleeve is rotatably disconnected from the first differential output gear, and in the engaged mode, the sleeve is rotatably connected to the first differential output gear. An electric actuator including a force plate coupled to the sleeve, the electric actuator being configured to achieve bidirectional axial movement, thereby axially pushing and pulling the force plate to place the coupling in one of the disengagement mode and the engagement mode.

14. The disconnectable differential assembly of claim 13, further comprising a sensor configured to detect when the connection is in the disconnected mode.

15. The disconnectable differential assembly according to claim 13, wherein, The force-bearing plate is a two-part force-bearing plate with an arc-shaped groove, and the sleeve has an arc-shaped protrusion located at the outermost radial part, wherein the arc-shaped protrusion is accommodated in the arc-shaped groove.

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