Differential cutter and rocker assembly

Abstract

A differential disconnect and rocker assembly for a vehicle includes a fixed housing, a rotatable ring gear, a differential housing and cover, and a pinion gear assembly including a pinion gear drivably connectable to the ring gear and a side gear meshing with the pinion gear. The assembly includes a differential disconnect assembly operatively connected between the ring gear and the pinion gear assembly, the differential disconnect assembly being operable to operatively disconnect the ring gear from the pinion gear assembly. The assembly also includes a differential rocker slidably coupled to the differential housing or cover and operatively connected to the side gear. The differential rocker is operable to operatively disconnect the differential housing or cover from the side gear to allow the side gear to rotate relative to the differential housing or differential cover.

Description

Technical Field

[0001] (Cross - Reference to Related Applications)

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 358,890, filed Jul. 7, 2022, and U.S. Provisional Application No. 63 / 446,060, filed Feb. 16, 2023, the disclosures of which are hereby incorporated by reference in their entireties.

[0002]

[0002] The present invention relates to a differential disconnect assembly for use in a power transmission system of a motor vehicle. More particularly, the present invention relates to a differential disconnect assembly having a locking differential for a self - propelled vehicle.

Background Art

[0003]

[0003] A self - propelled all - wheel drive (AWD) vehicle can be primarily driven by a front axle driven by a vehicle engine through a transmission. Power can also be transmitted to a rear axle by a power take - off device, a drive shaft, and a rear drive unit. The rear drive unit converts rotational force from the drive shaft to left and right side shafts to drive each of the left and right rear wheels of the vehicle. The side shafts are driven by side gears within a differential device supported by a differential housing and a cover, and are driven by the rotation of a ring gear. The side gears are meshed and engaged with pinion gears, and the pinion gears are driven by the ring gear, thereby transmitting torque to the side shafts. It is generally known that a vehicle includes a disconnect assembly engaged between the ring gear and the pinion gear to connect and disconnect the ring gear from the differential pinion gear of the differential device.

[0004]

[0004] It is generally known that a vehicle includes a differential locking device to prevent relative rotation of one driven wheel with respect to another driven wheel. This is typically accomplished by locking one differential side gear relative to the differential case or housing to prevent rotation of the side gear relative to the case or housing. It is also known to provide a hydraulically or electrically actuated clutch to lock and unlock the side gear of the differential assembly relative to the differential housing. However, such designs may be undesirable because they require the differential case or housing to be sufficiently robust to handle the torsional loads transmitted between the ring gear and the side gear.

[0005]

[0005] It would be desirable to remove the torsional load on the differential housing and allow the housing to be smaller while still meeting the requirements for axial and radial loads on the side gear, or even to eliminate the differential housing altogether. It would also be desirable to provide a single actuator configured to selectively engage the cutter assembly and the differential locking device.

Summary of the Invention

Means for Solving the Problems

[0006] According to one embodiment, a differential disconnect and rocker assembly for a vehicle is provided. The differential disconnect and rocker assembly includes a fixed housing, a rotatable ring gear rotatably supported by the fixed housing, a pinion gear assembly including a plurality of pinion gears drivingly connectable to the ring gear, and a plurality of side gears rotatably disposed within the fixed housing and meshing with the pinion gears to rotate therewith. The differential disconnect and rocker assembly also includes a differential housing and a differential cover rotatably supported by the fixed housing. The ring gear rotates with at least one of the differential housing and the differential cover. Further, disconnection of the ring gear from the pinion gear assembly enables the ring gear, the differential housing, and the differential cover to stop rotating while the side gears are rotating. The differential disconnect and rocker assembly also includes a differential disconnect assembly operatively connected between respective surfaces of the ring gear and the pinion gear assembly such that the ring gear, the pinion gears, and the side gears rotate together when connected. The differential disconnect assembly is operable to operatively disconnect the ring gear from the pinion gear assembly to prevent driving rotation of the ring gear by the pinion gears by disconnecting torque transmission between the ring gear and the pinion gears during wheel rotation. The differential disconnect and rocker assembly also includes a differential rocker slidably coupled to one or more of the differential housing and the differential cover and operatively connected to one of the side gears such that one or more of the differential housing and the differential cover and one of the side gears rotate together when connected. The differential rocker is operable to enable one of the side gears to rotate relative to one or more of the differential housing and the differential cover by operatively disconnecting one or more of the differential housing and the differential cover from one of the side gears.

[0007]

[0007] According to another embodiment, a differential disconnect and rocker assembly for a vehicle is provided. The differential disconnect and rocker assembly includes a fixed housing, a rotatable ring gear rotatably supported by the fixed housing, and a differential housing rotatably supported by the fixed housing. The ring gear rotates with the differential housing. The differential disconnect and rocker assembly also includes a pinion gear assembly having a plurality of pinion gears drivably connectable to the ring gear, a gear nest radially and axially supported by the differential housing and rotatable freely relative to the differential housing, and a plurality of side gears rotatably disposed within the fixed housing and meshing with the pinion gears to rotate with the pinion gears. The differential disconnect and rocker assembly also includes a differential disconnect assembly including a spline ring movable to engage and disengage with one or more of the ring gear and the gear nest so as to rotate together when the ring gear, the pinion gears, and the side gears are connected. The differential disconnect assembly also includes a shift ring fixedly connected to the spline ring, and the shift ring is movable to engage and disengage with one of the side gears to lock or unlock the side gear and the gear nest, respectively. The differential disconnect assembly is operable to operatively disconnect the ring gear from the gear nest to prevent driving rotation of the ring gear by the pinion gears by cutting off torque transmission between the ring gear and the pinion gears during wheel rotation. Disconnection of the ring gear from the pinion gear assembly enables the ring gear and the differential housing to stop rotating while the side gears are rotating.

[0008]

[0008] The advantages of the present invention will be readily recognized as the understanding thereof deepens by referring to the following detailed description taken in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0009]

Figure 1

[0009] FIG. 1 is a side cross-sectional view of a differential disconnect and rocker assembly according to a first embodiment of the present invention.

Figure 2

[0010] FIG. 1 is an enlarged side sectional view of a portion of a differential cutter - rocker assembly showing the differential cutter in a disconnected state and the differential rocker in an unlocked state according to a first embodiment of the present invention.

Figure 3

[0011] FIG. 2 is a side sectional view of a differential cutter - rocker assembly showing the differential cutter in a connected state and the differential rocker in an unlocked state.

Figure 4

[0012] FIG. 3 is a side sectional view of a differential cutter - rocker assembly showing the differential cutter in a connected state and the differential rocker in a locked state.

Figure 5

[0013] FIG. 4 is a front view of a shift collar of a differential cutter - rocker assembly and a portion of a differential case.

Figure 6

[0014] FIG. 4 is a front view of a shift collar of a differential cutter - rocker assembly and a side gear.

Figure 7

[0015] FIG. 21 is a perspective view of a differential cutter - rocker assembly in a disconnected unlocked condition where the cam actuator is in a disconnected unlocked position with respect to the cam ring according to a second embodiment of the present invention.

Figure 8

[0016] FIG. 7 is a side sectional view of a differential cutter - rocker assembly showing a spline ring in a disconnected unlocked position separated from a gear nest and a side gear.

Figure 9

[0017] FIG. 8 is an end sectional view of a portion of a differential cutter - rocker assembly showing a cam actuator and a cam ring according to a second embodiment of the present invention.

Figure 10

[0018] FIG. 9 is a side perspective view of a cam actuator and a cam ring showing the cam actuator in a disconnected unlocked position with respect to the cam ring.

Figure 11

[0019] FIG. 8 is an enlarged side sectional view of a portion of a differential cutter - rocker assembly showing a spline ring in a cut - off lock release position.

Figure 12

[0020] FIG. 7 is a perspective view of a portion of a differential cutter - rocker assembly showing a cam actuator in a connected unlocked position relative to a cam ring.

Figure 13

[0021] FIG. 12 is an enlarged side sectional view of a differential cutter - rocker assembly showing a spline ring in a connected lock release position engaged with a gear nest and disengaged from a side gear.

Figure 14

[0022] FIG. 12 is a perspective view of a portion of a differential cutter - rocker assembly showing a cam actuator in a connected locked position relative to a cam ring.

Figure 15

[0023] FIG. 14 is an enlarged side sectional view of a differential cutter - rocker assembly showing a spline ring in a connected lock position engaged with a gear nest and engaged with a side gear.

DETAILED DESCRIPTION OF THE INVENTION

[0010]

[0024] FIGS. 1 - 15 show components of a differential cutter - rocker assembly 10 for use in a self - propelled vehicle according to the embodiments described herein. References to directions such as top, bottom, upper, lower, upward, downward, in the length direction, in the width direction, left, right, etc., used or shown in the description, figures, or claims are relative terms used for ease of explanation and are not intended to limit the scope of the invention in any way. Referring to the figures, like numbers indicate like or corresponding parts throughout several figures.

[0011]

[0025] Referring to FIG. 1, a differential cutter / rocker assembly 10 (hereinafter, "cutter / rocker") is provided in a vehicle transmission 12 provided in a vehicle. The transmission 12 may be referred to as a vehicle axle, as will be understood from the following description. The transmission 12 includes a fixed housing 14 that defines an internal compartment, and the internal compartment houses a ring gear 16, a differential housing 18, and a differential cover 20. Further, the fixed housing 14 is fixedly supported on the vehicle. The transmission 12 is operatively connected to a drive shaft or vehicle drive train and an engine or motor, and the ring gear 16 is rotatably driven by the drive train. The ring gear 16 is configured to engage and be driven by a vehicle drive shaft or drive train, and the vehicle drive shaft or drive train is driven by a vehicle engine or motor. The ring gear 16 is supported both axially and radially by the differential housing 18 and the differential cover 20. Thus, the ring gear 16, the differential housing 18, and the differential cover 20 rotate together within the internal compartment in the fixed housing 14. The differential housing 18 and the differential cover 20 include respective end flanges 22 and 24 that are rotatably supported by the fixed housing 14 by a series of bearings 26. The fixed housing 14 defines a pair of bearing seats 28 that support the bearings 26. In an alternative form, it will be understood that this inventive design also allows the ring gear 16 to be directly supported by bearings on the fixed housing 14, thereby making it possible to eliminate either or both of the differential housing 18 or the differential cover 20.

[0012]

[0026] The transmission 12 shown in FIG. 1 includes a pinion gear assembly 30 rotatably supported within a fixed housing 14. The pinion gear assembly 30 includes opposed differential pinion gears 32, a pinion shaft 34, a differential gear nest 36, and opposed differential side gears 38. The differential pinion gears 32 (hereinafter, “pinion gears”) are rotatably connected to each other by a pinion shaft 34 mechanically connected to the differential gear nest 36 (hereinafter, “gear nest”). Further, the pinion gears 32 mesh and engage with the differential side gears 38 (hereinafter, “side gears”) such that torque can be transmitted from the gear nest 36 to the pinion gears 32 and then to the side gears 38.

[0013]

[0027] The pinion shaft 34 rotatably supports the pinion gears 32 at its ends and rotates with the pinion gears 32 when the pinion gears 32 move around the side gears 38. The cutter / rocker 10 further includes a connector pin 40 that fixes and couples the pinion shaft 34 to the gear nest 36 such that the pinion gears 32, the pinion shaft 34, and the gear nest 36 all move together around the same axis centerline as the side gears 38. The gear nest 36 is supported both radially and axially by the differential housing 18 and the differential cover 20 and can thus rotate freely in both directions when the gear nest 36 moves around the side gears 38 with the pinion gears 32. The gear nest 36 may be supported by other components such as the ring gear 16, the fixed housing 14, bearings, etc.

[0014]

[0028] As shown in FIG. 1, the side gear 38 is supported by the fixed housing 14, preferably by the differential housing 18 and the differential cover 20 respectively. The side gear 38 operates to transmit torque to any combination of shafts 42, which may be of any type such as output shafts, half shafts, link shafts, etc. as known in the art. Thus, these shafts 42 rotate with the vehicle wheels connected thereto and selectively drive the vehicle wheels. The housing end flange 22 and the cover end flange 24 are open to allow the shaft 40 of the side gear 38 to extend axially therefrom for driving the wheels. Due to the connection of the shafts 42 and the side gear 38 to the wheels, the shafts 42 and the side gear 38 rotate when the wheels rotate. The side gear 38 meshes and engages with the pinion gear 32, and the ring gear 16 is engageable with the gear nest 36 such that torque can be transmitted from the ring gear 16 through the gear nest 36, the pinion gear 32, and the side gear 38 to drive the shaft 42.

[0015]

[0029] However, as described above, it is desirable to disengage the ring gear 16 from the side gear 38 so that the ring gear 16 does not always have to rotate when the vehicle wheels are rotating. Thus, the transmission 12 includes a cutter / locker 10 having a differential disconnect assembly 44 (hereinafter, "differential disconnect") provided between the ring gear 16 and the pinion gear assembly 30, preferably between the ring gear 16 and the gear nest 36, and the differential disconnect 44 is selectively operated to connect and disconnect the ring gear 16 and the pinion 32. Disconnecting the ring gear 16 from the gear nest 36 allows the ring gear 16, the differential housing 18, the bearing 26, and the remainder of the transmission 12 to stop rotating while the vehicle wheels are rotating.

[0016]

[0030] In this embodiment, the differential disconnect 44 is normally disconnected. To connect the gear nest 36 and the ring gear 16, the differential disconnect 44 includes a spline ring 46 that is radially guided and axially slidable inside the differential housing 18. Referring to FIG. 2, the spline ring 46 has an outer surface that preferably includes a radial connector projection 48, and the radial connector projection 48 engages with a complementary connector formation 50 on the inner surface of the ring gear 16 to define a mechanical connection that rotationally locks the spline ring 46 relative to the ring gear 16. The connector projection 48 may be formed as a spline tooth or other similar structure that locks the relative rotation of the ring gear 16 and the spline ring 46 when engaged while allowing axial displacement of the spline ring 46 between the cutting position in FIG. 2 and the connection position in FIG. 3. In an alternative form, it will be understood that the spline ring 46 can be mechanically connected to the gear nest 36 and slidably engaged and disengaged with the ring gear 16, particularly when the differential housing 18 and / or the differential cover 20 are removed.

[0017]

[0031] Referring to FIGS. 2 and 3, the spline ring 46 is releasably connected and disconnected from the gear nest 36 during axial sliding of the spline ring 46, and releasably connects the ring gear 16 to the gear nest 36 and the pinion gear 32. As shown in FIG. 2, the differential disconnect 44 includes a releasable disconnect clutch 52, which is preferably defined by a series of clutch teeth or other similar locking formations 54 on the inner diameter portion or inner surface of the spline ring 46, and complementary locking formations 56 on the outer diameter portion or outer surface of the gear nest 36. In an alternative form, it will be understood that the spline ring 46 may be mechanically connected to the gear nest 36 and slidably engaged and disengaged with the ring gear 16 to connect and disconnect torque transmission, particularly when the differential housing 18 and / or the differential cover 20 are eliminated. Further, the differential disconnect 44 is operatively connected between the proximal end of the spline ring 46 and the differential cover 20, and includes a disconnect return spring 58 (hereinafter, "disconnect spring") configured to bias the spline ring 46 toward the disconnect position relative to the locking formation 56 on the gear nest 36. Further, the spline ring 46 includes one or more drive arms 60 that extend axially away from the proximal end of the spline ring 46. The disconnect spring 58 acts as a biasing member for constantly biasing the spline ring 46 to engage or disengage from the ring gear 16 and the gear nest 36.

[0018]

[0032] As shown in FIG. 2, differential cutter 44 also includes a cutter actuator 62 operatively coupled to drive arm 60 and configured to selectively reposition spline ring 46 between a cutting position (FIG. 2) and a connection position (FIG. 3). In operation, when cutter actuator 62 is actuated, cutter actuator 62 moves spline ring 46 axially inwardly (arrow 64), engaging spline ring 46 with cutter clutch 52 between spline ring 46 and gear nest 36 as seen in FIG. 3, enabling torque to be transmitted from ring gear 16 through spline ring 46 to gear nest 36. Cutter spring 58 moves spline ring 46 axially outwardly (arrow 64') when cutter actuator 62 is deactivated, disengaging cutter clutch 52 between spline ring 46 and gear nest 36, thereby enabling gear nest 36 to rotate freely relative to ring gear 16. In this embodiment, spline ring 46 is constantly biased by cutter spring 58 to the cutting or open state shown in FIG. 2. Further, cutter actuator 62 is actuated or operated to drive spline ring 46 axially inwardly (arrow 64) to the connection or closed state of FIG. 3.

[0019]

[0033] As shown in FIG. 2, the cutter spring 58 constantly biases the spline ring 46 to the open position of FIG. 2, and the locking forming portions 54 and 56 are separated and disengaged so that the ring gear 16 is rotatably cut off from the gear nest 36. However, the spline ring 46 may be axially driven by the cutter actuator 62 to engage the locking forming portions 54 and 56 of the cutter clutch 52 as seen in FIG. 3 when the cutter actuator 62 is operated and actuated. Referring to FIG. 2, the inner surface of the ring gear 16 and the outer surface of the gear nest 36, in combination with the side wall 66 of the differential housing 18 and the opposing radial wall 68 of the differential cover 20, essentially define opposing surfaces that are spaced apart to allow axial sliding of the outer shoulder 70 of the spline ring 46 during movement of the spline ring 46. Further, the drive arm 60 projects axially through a complementary window 72 in the differential housing 18. When the cutter actuator 62 is actuated as shown in FIG. 3, the ring gear 16 is rotatably connected to the gear nest 36 to transmit torque from the ring gear 16 through the spline ring 46 to the gear nest 36 as indicated by the arrow 74. When the cutter actuator 62 is deactivated, the cutter spring 58 returns the spline ring 46 to the open cutting position of FIG. 2, where the cutter clutch 52 is disengaged to allow the gear nest 36 to rotate freely relative to the ring gear 16.

[0020]

[0034] Referring to FIG. 1, to drive the spline ring 46, the cutter actuator 62 includes a drive unit 76 fixedly supported to the fixed housing 14. The drive unit 76 includes a slide ring or pusher 78 axially displaceable between the position of FIG. 2 and the position of FIG. 3. The cutter actuator 62 is preferably an electromagnetic actuator 62, in which case the pusher 78 is axially driven by the drive unit 76 using electromagnetic force. It will be understood that other types of actuators, such as a motor, a worm gear, a cam, a ball ramp, a hydraulic or pneumatic piston, or other suitable actuator, are suitable. As shown in FIG. 1, the pusher 78 can axially drive an intermediate collar 80, and the intermediate collar 80 drives a radial plate 82. The intermediate collar 80 is formed of a non-magnetic material so as not to interfere with the function of the pusher 78. A spacer 84 may be provided to control the radial and axial positions of the pusher 78. The drive arm 60 projects axially through a complementary window 72 in the differential housing 18, such that the drive arm 60 contacts the radial plate 82 and can be driven by the pusher 78 through the intermediate collar 80. The drive arm 60 preferably does not contact the window 72 of the differential housing 18 to allow axial movement of the spline ring 46.

[0021]

[0035] During rotation of the ring gear 16, the drive unit 76 remains stationary, while the pusher 78, intermediate collar 80, and radial plate 82 are axially movable but preferably do not rotate with the spline ring 46. The fixed housing 14 may include an anti-rotation feature (not shown) to prevent rotation of the radial plate 82. Further, the drive unit 76 includes a position sensor (not shown) for reading the position of the radial plate 82, and the radial plate 82 serves as a target for the position sensor. The spline ring 46 can rotate and slide along the radial plate 82. It will be understood that other types of drive units 76 may be used to selectively displace the spline ring 46. When the drive unit 76 is deactivated, the cutter spring 58 biases the spline ring 46, radial plate 82, intermediate collar 80, and pusher 78 outward (arrow 64') to their original positions in FIGS. 1 and 2, opening the spline connection 52 (i.e., the cutter clutch), and when the drive unit 76 is activated, the reverse movement (arrow 64) of those components occurs, closing the cutter clutch 52 as shown in FIG. 3.

[0022]

[0036] This system is essentially mono-stable because the spline ring 46 normally remains in the cutting positions of FIGS. 1 and 2 unless the cutter actuator 62 is actuated to move the spline ring 46 to the connection position of FIG. 3, and until it is actuated. When the cutter actuator 62 is deactivated, the spline ring 46 returns to the cutting position (FIGS. 1 and 2) due to the biasing of the cutter spring 58. Further, the normal positions in FIGS. 1 and 2 are preferably open cutting positions, and the actuated position in FIG. 3 is a closed connection position. It will be understood that the configuration of the spline ring 46 and cutter spring 58 may be modified to operate such that the normal position is a closed connection position and the actuated position is an open cutting position. It will be recognized that the system may be configured as bi-stable such that the spline ring 46 remains in its current position until the system re-positions the spline ring 46.

[0023]

[0037] As shown in FIG. 1, in order to reduce the space requirement of the cutter actuator 62, the drive unit 76 is preferably positioned in an annular pocket 88 defined axially between the bearing 26 adjacent to the side wall 66 of the differential housing 18 and radially outward of the end flange 22 of the differential housing 18. This allows the drive unit 76 to fit radially inward of the pusher 78, the intermediate collar 80, and the spacer 84 and reduce the radial size of the transmission 12 in this region. These components are surrounded by the radial wall section 90 and the annular wall section 92 of the fixed housing 14 to define the actuator compartment 94.

[0024]

[0038] The spline ring 46 is arranged radially between the ring gear 16 and the gear nest 36. Instead, the spline ring 46 may be arranged axially between a modified ring gear and a modified gear nest to perform the functions described herein. Further, the differential cutter 44 may incorporate other structures such as a dog clutch or clutch plate that selectively connect and disconnect the torque transmission between the ring gear 16 and the pinion gear 32, instead of the spline ring 46. In these alternative designs, torque transmission through the differential housing does not occur. This three-piece differential device design removes the torsional load from the differential housing 18 and allows the differential housing 18 to be made of a variety of materials that are still smaller and / or can still handle the axial and radial load requirements on the cutter / rocker 10, or allows the differential housing 18 to be completely eliminated.

[0025]

[0039] As described above, it is desirable to selectively couple the differential cover 20 to one of the side gears 38. Thus, the disconnecter / rocker 10 also includes a differential rocker 96 that is selectively actuated to connect and disconnect the differential cover 20 to and from the side gear 38. Disconnection of the differential cover 20 and the adjacent side gear 38 allows the side gear 38 to rotate independently of the differential cover 20. The differential rocker 96 is normally unlocked in this embodiment. When the differential rocker 96 is in the unlocked state, the side gear 38 can rotate freely relative to the differential cover 20, and the disconnecter / rocker 10 acts as a standard open differential. However, when the differential rocker 96 is in the locked state, the differential rocker 96 prevents rotation of one of the side gears 38 relative to the differential cover 20. It will be appreciated that, without changing the scope of the present invention, the differential rocker 96 may be provided between the differential housing 18 and the other side gear 38.

[0026]

[0040] Referring to FIG. 2, in order to connect one of the side gears 38 to the differential cover 20, the differential rocker 96 includes a shift collar 98 that is radially guided and axially slidable outside the differential cover 20. Referring to FIGS. 2 and 4, the shift collar 98 releasably connects and disconnects from the side gear 38 during axial sliding of the shift collar 98 in order to releasably connect the differential cover 20 to the side gear 38. As shown in FIGS. 2 and 6, the differential rocker 96 includes a releasable rocker clutch 100, which is preferably defined by a series of clutch teeth or similar locking formations 102 on the outer diameter or outer surface of the side gear 38, and complementary locking protrusions 104 on the inner diameter or inner surface of the shift collar 98. The locking formations 102 on the side gear 38 engage with the complementary locking protrusions 104 on the shift collar 98 to define a mechanical connection that rotationally locks the shift collar 98 to the side gear 38. The locking formations 102 and the complementary locking protrusions 104 may be formed as spline teeth or other similar structures that prevent relative rotation of the differential cover 20 and the side gear 38 when engaged while allowing axial displacement of the shift collar 98 between the unlock position of FIG. 2 and the lock position of FIG. 4.

[0027]

[0041] As shown in FIG. 2, the differential cover 20 includes a pocket wall 106 that extends axially from the radial wall 68 toward the end flange 24 and terminates at a stop wall 108, and the stop wall 108 extends radially inward from the pocket wall 106. Further, the differential cover 20 includes an intermediate flange 110 that extends axially outward from the stop wall 108. Further, the differential cover 20 includes a connector wall 112 that extends radially inward from the inner surface 114 of the intermediate flange 110 and is adjacent to the end flange 24. As shown in FIG. 5, the differential cover 20 includes a plurality of spaced channels 116 that extend axially and are circumferentially spaced around the intermediate flange 110. Each channel 116 includes a channel base 118 that extends circumferentially between opposing channel walls 120, 122, and the channel walls 120, 122 extend radially inward from the outer surface of the intermediate flange 110.

[0028]

[0042] Referring to FIGS. 2 and 5, shift collar 98 is generally ring-shaped and includes a main ring 124 having an inner surface configured to slide along the outer surface of intermediate flange 110. Shift collar 98 includes an outer rim 126 that extends radially outward from the outer surface of main ring 124. Further, shift collar 98 includes a plurality of circumferentially spaced locking protrusions 104 that extend radially inward from the inner surface of main ring 124. The number of spaced locking protrusions 104 corresponds to the number of channels 116 in differential cover 20. Further, locking protrusions 104 are sized and shaped such that each mates with a respective channel 116 when shift collar 98 is assembled with differential cover 20. Each locking protrusion 104 includes opposing protrusion walls 128, 130 that extend radially inward from main ring 124 and an end wall 132 that extends circumferentially between the distal ends of opposing protrusion walls 128, 130. It will be appreciated that without changing the scope of the present invention, protrusion walls 128, 130 and end wall 132, channel walls 120, 122 and channel base 118 may be tapered radially and / or axially. As shown in FIG. 2, end wall 132 of locking protrusion 104 is spaced radially inward of inner surface 114 of intermediate flange 110.

[0029]

[0043] As shown in FIG. 6, one of the side gears 38 includes an outer ring 134 that projects radially outward from the side gear 38. Further, the side gear 38 includes a plurality of circumferentially spaced locking formation portions 102 that extend axially through the outer ring 134 and project radially inward from the outer surface 136 of the outer ring 134. The locking formation portions 102 are defined by a formation portion base 138 that extends circumferentially between opposing formation portion walls 140, 142, and the formation portion walls 140, 142 extend radially inward from the outer surface 136 of the outer ring 134. The locking formation portions 102 are sized and shaped to engage integrally with respective locking projections 104 on the shift collar 98. It will be appreciated that the formation portion walls 140, 142 and the formation portion base 138 may be tapered axially and / or radially without changing the scope of the present invention. The number of locking formation portions 102 is greater than or equal to the number of locking projections 104. Referring to FIG. 2, the outer surface 136 of the side gear 38 is spaced radially inward of the inner surface 114 of the intermediate flange 110 on the differential cover 20 such that the side gear 38 can rotate relative to the differential cover 20. Further, the outer surface 136 of the side gear 38 is spaced radially outward of the end wall 132 of the shift collar 98, and the formation portion base 138 is spaced radially inward of the end wall 132 of the shift collar 98, such that the locking projections 104 can engage and disengage integrally with respective locking formation portions 102 in the side gear 38 when the shift collar 98 is axially moved along the differential cover 20.

[0030]

[0044] Referring to FIGS. 2 and 4 - 6, the shift collar 98 is radially guided and axially slidable along the intermediate flange 110 of the differential cover 20, and the locking protrusion 104 slides along respective channels 116 in the intermediate flange 110. The shift collar 98 is axially slidable between the unlocked position shown in FIG. 2 and the locked position shown in FIG. 4. In the unlocked position shown in FIG. 2, the locking protrusion 104 of the shift collar 98 is axially spaced from the locking formation 102 in the side gear 38, allowing the side gear 38 to rotate independently of the differential cover 20. In the locked position shown in FIG. 4, the locking protrusion 104 of the shift collar 98 is at least partially inserted into the locking formation 102 in the side gear 38, preventing rotation of the side gear 38 relative to the differential cover 20, and the differential cover 20 rotates with the ring gear 16.

[0031]

[0045] Also as shown in FIG. 2, the differential rocker 96 includes a rocker return spring 144 (hereinafter, "rocker spring") operatively connected between the radial wall 68 of the differential cover 20 and the outer rim 126 on the shift collar 98. The rocker spring 144 is configured to bias the shift collar 98 toward the unlocked position of FIG. 2 relative to the locking formation 102 on the side gear 38. The rocker spring 144 acts as a biasing member for constantly biasing the shift collar 98 to engage or disengage from the side gear 38.

[0032]

[0046] As shown in FIG. 2, the differential rocker 96 also includes a rocker actuator 146 operatively connected to the outer rim 126 and configured to selectively reposition the shift collar 98 between an unlocked position (FIG. 2) and a locked position (FIG. 4). In operation, when the rocker actuator 146 is actuated, the rocker actuator 146 moves the shift collar 98 axially inwardly (arrow 64') as seen in FIG. 4, engaging the rocker clutch 100 between the shift collar 98 and the side gear 38, allowing torque to be transmitted from the ring gear 16 through the differential cover 20, the shift collar 98 to the side gear 38 as indicated by arrow 147. The rocker spring 144 moves the shift collar 98 axially outwardly (arrow 64) when the rocker actuator 146 is deactivated, disengaging the rocker clutch 100 between the shift collar 98 and the side gear 38, thereby allowing the side gear 38 to rotate freely relative to the ring gear 16. In this embodiment, the shift collar 98 is constantly biased by the rocker spring 144 to the unlocked or open state shown in FIG. 2. The rocker actuator 146 is actuated or operated to drive the shift collar 98 axially inwardly (arrow 64') to the locked or closed state of FIG. 4.

[0033]

[0047] Referring to FIG. 1, to drive the shift collar 98, the rocker actuator 146 includes a drive unit 148 fixedly supported to the fixed housing 14. The drive unit 148 includes a slide ring or pusher 150 axially displaceable between the position of FIG. 2 and the position of FIG. 4. The rocker actuator 146 is preferably an electromagnetic actuator, in which case the pusher 150 is axially driven by the drive unit 148 using electromagnetic force. It will be understood that other types of actuators are suitable, such as motors, worm gears, cams, ball ramps, hydraulic or pneumatic pistons, or other suitable actuators. The pusher 150 can axially drive an intermediate collar 152, and the intermediate collar 152 drives a radial plate 154. A spacer 156 may be provided to control the radial and axial positions of the pusher 150. The shift collar 98 contacts the radial plate 154, and the radial plate 154 is driven by the pusher 150 through the intermediate collar 152. The rocker spring 144 biases the shift collar 98 toward engagement with the radial plate 154.

[0034]

[0048] During rotation of the ring gear 16, the drive unit 148 remains stationary, while the pusher 150, intermediate collar 152, and radial plate 154 are axially movable but preferably do not rotate with the shift collar 98. The fixed housing 14 may include an anti-rotation feature (not shown) to prevent rotation of the radial plate 154. Further, the drive unit 148 also includes a position sensor (not shown) for reading the position of a target (not shown) on the intermediate collar 152. The shift collar 98 can rotate and slide along the radial plate 154. It will be understood that other types of drive units 148 may be used to selectively displace the shift collar 98. When the drive unit 148 is deactivated, the rocker spring 144 biases the shift collar 98, radial plate 154, intermediate collar 152, and pusher 150 to their original positions in FIGS. 1-3, opening the rocker clutch 100, and when the drive unit 148 is activated, reverse movement of those components occurs, closing the rocker clutch 100 as shown in FIG. 4.

[0035]

[0049] This system is essentially monostable since the shift collar 98 normally remains in the unlocked positions of FIGS. 1-3 until the rocker actuator 146 is activated to move the shift collar 98 to the locked position of FIG. 4. When the rocker actuator 146 is deactivated, the shift collar 98 returns to the unlocked position (FIGS. 1-3) due to the biasing of the rocker spring 144. Further, the normal positions of FIGS. 1-3 are preferably the open unlocked positions, and the operating position of FIG. 4 is the closed locked position. During operation, the differential rocker 96 is selectively operated to connect the differential cover 20 to the side gear 38 while the differential cutter 44 connects the ring gear 16 to the gear nest 36 as shown in FIG. 4. It will be understood that the configuration of the shift collar 98 and rocker spring 144 may be modified to operate such that the normal position is the closed locked position and the operating position is the open unlocked position.

[0036]

[0050] As shown in FIG. 1, in order to reduce the space requirement of the rocker actuator 146, the drive unit 148 is preferably positioned in an annular pocket 158 defined axially between a bearing 26 adjacent to the intermediate flange 110 of the differential cover 20 and radially outward of the end flange 24 of the differential cover 20. This allows the drive unit 148 to fit radially inward of the pusher 150, intermediate collar 152, and spacer 156 and reduce the radial size of the transmission 12 in this region. These components are surrounded by the radial wall section 160 and the annular wall section 162 of the fixed housing 14 to define the actuator compartment 164.

[0037]

[0051] A second embodiment of the cutter / rocker 10' using common parts designated by common reference numerals is shown in FIGS. 7-15, where like reference numerals with prime symbols represent elements similar to those described above. Referring to FIG. 8, in this modified transmission 12', the functions of some components of the differential cutter 44 and the differential rocker 96 are combined such that the cutter / rocker 10' includes a single actuator 166 instead of the cutter actuator 62 and the rocker actuator 146 of the cutter / rocker 10 described above. The actuator 166 actuates both the cutter clutch 52' between the spline ring 46' and the gear nest 36', and the rocker clutch 100' between the spline ring 46' and the side gear 38'. Only the significant differences between the two embodiments are reflected in the figures and the following description.

[0038]

[0052] More specifically, the modified transmission 12' operates substantially the same as the transmission 12, where the rotatable ring gear 16 is disposed in the fixed housing 14', and is rotatably supported both axially and radially by the differential housing 18' and the differential cover 20', and the ring gear 16, differential housing 18', and differential cover 20' rotate together within the internal compartment of the fixed housing 14'.

[0039]

[0053] The side gear 38' is selectively driven by the rotation of the ring gear 16 by means of a pinion gear 32 operatively connected between the side gear 38' and the ring gear 16. The pinion gear 32 is rotatably connected to each other in the pinion assembly 30', and the pinion gear 32 moves around the side gear 38'. The pinion assembly 30' further includes a gear nest 36', the side gear 38' meshes and engages with the pinion gear 32, and the ring gear 16 can engage with the gear nest 36' so that torque can be transmitted through the gear nest 36', the pinion gear 32, and the side gear 38' to drive the shaft 42.

[0040]

[0054] As shown in FIG. 8, the cutter / locker 10' is provided between the ring gear 16 and the gear nest 36', where the cutter / locker 10' is selectively or intermittently operated to connect and disconnect the ring gear 16 and the gear nest 36'. The cutter / locker 10' includes a modified spline ring 46', which is radially guided and axially slidable inside the differential housing 18' like the spline ring 46 in the foregoing embodiment. The spline ring 46' has an outer surface, which preferably includes a radial connector protrusion 48'. The radial connector protrusion 48' engages with a complementary connector formation 50' on the inner surface of the ring gear 16 to define a mechanical connection portion that rotationally locks the spline ring 46' to the ring gear 16. The connector protrusion 48' may be formed as a spline tooth or other similar structure that locks the relative rotation between the ring gear 16 and the spline ring 46' when engaged while allowing axial displacement of the spline ring 46' between the cutting unlock position in FIGS. 8 and 11, the connection unlock position in FIG. 13, and the connection lock position in FIG. 15. In an alternative form, it will be understood that the spline ring 46' may be mechanically connected to the gear nest 36' and slidably engage and disengage with the ring gear 16.

[0041]

[0055] Referring to FIGS. 11 and 13, the spline ring 46' is releasably connected to the gear nest 36' during axial sliding of the spline ring 46' in order to releasably connect the ring gear 16 to the gear nest 36' and the pinion gear 32, and is disconnected from the gear nest 36'. Specifically, the cutter / locker 10' includes a releasable cutter clutch 52', and this cutter clutch 52' is preferably defined by a series of clutch teeth or other similar locking formations 54' on the inner diameter portion or inner surface of the spline ring 46', and complementary locking formations 56' on the outer diameter portion or outer surface of the gear nest 36'.

[0042]

[0056] The cutter / locker 10' is also operatively connected between the proximal end of the spline ring 46' and the differential cover 20', and includes a return spring 58' configured to bias the spline ring 46' toward a cutting unlock position (FIG. 11) with respect to the locking formation 56' on the gear nest 36'. Further, the spline ring 46' includes one or more drive arms 60' that extend axially away from the proximal end of the spline ring 46' and pass through respective windows 72' in the differential housing 18'. The return spring 58' acts as a biasing member for constantly biasing the spline ring 46' to engage or disengage with the side gear 38 and the gear nest 36'.

[0043]

[0057] The spline ring 46’ is also configured to selectively couple with one of the gear nest 36’ and the side gear 38’ to directly provide torque to one of the side gears 38’, and one of the side gears 38’ provides a rocker function. The disconnection between the gear nest 36’ and the side gear 38’ enables the side gear 38’ to rotate independently of the gear nest 36’. The disconnecter / rocker 10’ is normally in the disconnect lock release state in this embodiment, and the spline ring 46’ is in the disconnect lock release position shown in FIG. 11. When the disconnecter / rocker 10’ is in the connection lock release state (FIGS. 12 and 13) and the spline ring 46’ is in the connection lock release position, the side gear 38’ can rotate freely with respect to the gear nest 36’, and the disconnecter / rocker 10’ acts as a standard open differential. However, when the disconnecter / rocker 10’ is in the connection lock state (FIGS. 14 and 15), the spline ring 46’ is in the connection lock position, preventing the rotation of one of the side gears 38’ with respect to the gear nest 36’. It will be recognized that the spline ring 46’ may be provided between the differential cover 20’ and the other side gear 38’ without changing the scope of the present invention.

[0044]

[0058] Referring to FIG. 11, in order to connect one of the side gears 38' to the gear nest 36', the spline ring 46' includes a shift ring 168 that extends radially inwardly from the spline ring 46' and is fixedly connected to the spline ring 46'. The shift ring 168 is axially positioned between the locking formation 54' and the drive arm 60' along the inner surface of the spline ring 46'. Referring to FIGS. 11 and 15, the shift ring 168 releasably connects and disconnects from the side gear 38' during axial sliding of the spline ring 46' in order to releasably connect the gear nest 36' to the side gear 38'. The cutter / locker 10' includes a releasable rocker clutch 100', which is preferably defined by a series of clutch teeth or similar locking formations 102' on the outer diameter or outer surface of the side gear 38', and complementary locking protrusions 104' on the inner diameter or inner surface of the shift ring 168. The locking formation 102' on the side gear 38' engages the complementary locking protrusion 104' on the shift ring 168 to define a mechanical connection that rotationally locks the spline ring 46' relative to the side gear 38'. The locking formation 102' and the complementary locking protrusion 104' may be formed as spline teeth or other similar structures that lock the relative rotation of the gear nest 36' and the side gear 38' when engaged while allowing axial displacement of the spline ring 46' between the cutting unlock position of FIG. 11, the connection unlock position of FIG. 13, and the connection lock position of FIG. 15.

[0045]

[0059] As shown in FIGS. 7 and 8, the actuator 166 includes a motor 170, a drive gear 172, a sector gear 174, a cam ring 176, an outer thrust ring 178, and an inner thrust ring 180. The motor 170 is fixedly connected to the fixed housing 14' and drives a drive gear 172 that meshes with the sector gear 174. The drive gear 172 is rotatably supported within the fixed housing 14'. The sector gear 174 is fixed to a cam actuator 182, and the cam actuator 182 is axially supported by an outer thrust ring 178 that abuts a radial wall section 184 of the fixed housing 14' and is rotatably supported by a thrust collar 186 that abuts an annular ledge 188 extending axially from the radial wall section 184. The sector gear 174 includes circumferentially spaced cam lobes 190 for engaging the cam ring 176.

[0046]

[0060] The cam ring 176, the outer thrust ring 178, and the inner thrust ring 180 are generally ring-shaped and include circumferentially spaced locator tabs 192, 194, 196 that project radially outwardly from the respective outer diameter portions or outer surfaces of the rings 176, 178, 180. As shown in FIG. 8, the sector gear 174, the cam ring 176, the outer thrust ring 178, the inner thrust ring 180, and the thrust collar 186 are positioned within a cam cavity 198 within the fixed housing 14' defined between the outer surface of the differential housing 18', an adjacent bearing 26, and the radial wall section 184, the annular ledge 188, and the annular wall section 200 of the fixed housing 14'. The annular wall section 200 is spaced radially outwardly from the annular ledge 188.

[0047]

[0061] Referring to FIGS. 8 and 9, the stationary housing 14' includes a sector cavity 202 that is adjacent to the cam cavity 198 and extends radially outward from the cam cavity 198. The cam cavity 198 also includes locator slots 204 that are circumferentially spaced around the outer diameter or outer surface of the cam cavity 198 and extend axially. The locator slots 204 are sized and shaped to engage integrally with locator tabs 192, 194, 196 on the cam ring 176, the outer thrust ring 178, and the inner thrust ring 180 to prevent rotation of the rings 176, 178, 180 while allowing axial movement of the cam ring 176 and the inner thrust ring 180 along the locator slots 204.

[0048]

[0062] As shown in FIG. 8, the outer thrust ring 178 abuts against the radial wall section 184 of the fixed housing 14' with the locator tabs 194 positioned within their respective locator slots 204. The cam actuator 182 is positioned axially inward from the outer thrust ring 178 with the sector gear 174 positioned within the sector cavity 202. The sector gear 174 is rotatable within the sector cavity 202. The cam ring 176 is positioned axially inward from the cam actuator 182. The inner thrust ring 180 is positioned axially inward of the cam ring 176 and axially outward of the spline ring 46'. Further, the cam actuator 182, the cam ring 176, and the outer and inner thrust rings 178, 180 are positioned radially outward of the end flange 22' of the differential housing 18'. The outer and inner thrust rings 178, 180, and the cam ring 176 are rotationally locked to the fixed housing 14' by locator tabs 192, 194, 196 positioned within the locator slots 204. However, the inner thrust ring 180 and the cam ring 176 are axially slidable within the fixed housing 14' between the cut-off lock release position of FIG. 11 and the connection lock position of FIG. 15 since the locator tabs 192, 196 are axially slidable along their respective locator slots 204. The return spring 58' biases the spline ring 46', the inner thrust ring 180, the cam ring 176, the cam actuator 182, and the outer thrust ring 178 axially outward toward the fixed housing 14'. Thus, the return spring 58' biases the spline ring 46' toward the cut-off lock release position relative to the cutter clutch 52' and the rocker clutch 100'.

[0049]

[0063] Referring to FIG. 10, the cam lobe 190 of the cam actuator 182 includes a ramp portion 206 adjacent to the cam peak 208, and the cam lobe 190 projects axially toward the cam ring 176. The ramp portion 206 includes an intermediate portion 210 circumferentially spaced between the base portion 212 and the peak portion 214 adjacent to the cam peak 208. The peak portion 214 optionally includes the cam peak 208. The cam ring 176 is generally ring-shaped and includes a ring base 216 and circumferentially spaced cam ramps 218 that project axially away from the ring base 216 toward the cam actuator 182. The number of cam ramps 218 generally corresponds to the number of cam lobes 190 on the cam actuator 182. The cam lobes 190 on the cam actuator 182 and the cam ramps 218 of the cam ring 176 are sized and shaped such that rotation of the cam actuator 182 axially displaces the cam ring 176 relative to the cam lobes 190, and the cam ring 176 further axially moves the spline ring 46'. The axial position of the spline ring 46' is controlled by contact of the cam ramps 218 with the respective ramp portions 206 of the cam actuator 182. Further, the ring base 216 is configured to provide an axial clearance for the cam peak 208 when the cam actuator 182 is rotated relative to the cam ring 176. As further described below, the intermediate portion 210 and the peak portion 214 may be inclined portions such that the actuator 166 is monostable.

[0050]

[0064] In this embodiment, the spline ring 46' is constantly biased by a return spring 58' to the cutting lock release state (i.e., the open state) shown in FIG. 11. The actuator 166 is actuated or operated to rotate the cam actuator 182 and axially move the spline ring 46' to the connection unlock position (FIGS. 12 and 13) on the cam ring 176. The spline ring 46' engages with the cutter clutch 52' to enable torque to be transmitted from the ring gear 16 through the spline ring 46' to the gear nest 36'. Further, the actuator 166 also axially moves the spline ring 46' to the connection lock position (FIGS. 14 and 15) on the cam ring 176. The spline ring 46' engages with the rocker clutch 100', and the rocker clutch 100' rotationally fixes the side gear 38' relative to the gear nest 36' to prevent rotation of the side gear 38' relative to the gear nest 36'. Thus, a single actuator 166 can operate the cutter clutch 52' between the ring gear 16 and the gear nest 36', and the rocker clutch 100' between the side gear 38' and the gear nest 36'.

[0051]

[0065] First, the cutter / rocker 10' is in the cutter unlock state shown in FIGS. 7, 8, and 11, the cutter clutch 52' is disengaged, the rocker clutch 100' is unlocked, the spline ring 46' is in the cutter unlock position, and the base portion 212 of the cam lobe 190 is engaged with the cam ramp 218. When the cutter / rocker 10' is in the cutter unlock state, the gear nest 36' rotates freely relative to the ring gear 16, and the side gear 38' rotates freely relative to the gear nest 36'. Referring to FIG. 7, to selectively engage the cutter clutch 52', the actuator 166 activates the motor 170, and the motor 170 drives the drive gear 172 in the forward rotation direction 220 to rotate the sector gear 174 and the attached cam actuator 182 in the first rotation direction 222. It will be recognized that, without changing the scope of the present invention, the forward rotation direction 220 may be either clockwise or counterclockwise. Further, it will be recognized that, without changing the scope of the present invention, the first rotation direction 222 may be either clockwise or counterclockwise. Referring to FIGS. 12 and 13, the cam actuator 182 is rotated in the first rotation direction 222 until the intermediate portion 210 of the cam lobe 190 engages the respective cam ramp 218, and this engagement moves the cam ring 176 axially in the inward direction (arrow 224). The axial movement of the cam ring 176 in the inward direction (arrow 224) axially moves the spline ring 46' to the connection unlock position (FIG. 13) in the inward direction (arrow 224), engaging the spline ring 46' with the cutter clutch 52' between the spline ring 46' and the gear nest 36', enabling torque to be transmitted from the ring gear 16 through the spline ring 46' to the gear nest 36'.

[0052]

[0066] After the cutter / rocker 10’ is in the connection lock release state, the actuator 166 maintains the motor 170 at a predetermined first rotational position. This first rotational position is such that the cutter clutch 52’ is engaged, the rocker clutch 100’ is in the disengaged state, the spline ring 46’ is in the connection lock release position, and the intermediate portion 210 of the cam lobe 190 is engaged with the cam ramp 218 of the cam ring 176, holding the cutter / rocker 10’ in the connection lock release state. The rocker clutch 100’ is maintained in the disengaged state while the cutter clutch 52’ is engaged because the peak portion 214 of the cam lobe 190 is separated from the cam clamp 218. It will be recognized that the motor 170 may include a motor encoder (not shown) configured to provide feedback indicating the rotational position of the motor 170 to the actuator 166. The actuator 166 may be configured to be monostable in the connection lock release state such that the motor 170 is held at the first predetermined rotational position to maintain the cutter / rocker 10’ in the connection lock release state. Since the intermediate portion 210 is inclined, the actuator 166 is monostable in the connection lock release state. Thus, when the cutter / rocker 10’ is in the connection lock release state and the motor 170 is deactivated (i.e., power is removed from the motor 170), the return spring 58’ drives the motor 170 in reverse due to the inclination at the intermediate portion 210. Accordingly, the cutter / rocker 10’ is maintained in the connection lock release state while the actuator 166 provides power to the motor 170, and the cutter / rocker 10’ is automatically returned to the cutting lock release state by the return spring 56’ when the motor 170 is deactivated.

[0053]

[0067] The cutter / rocker 10' can be placed in a connection lock state by the actuator 166 when in a connection unlock state by engaging the rocker clutch 100'. Referring to FIG. 14, to engage the rocker clutch 100', the actuator 166 operates the motor 170, and the motor 170 drives the drive gear 172 in the forward rotation direction 220 to rotate the sector gear 174 and the attached cam actuator 182 in the first rotation direction 222, engaging the peak portions 214 of the cam lobes 190 with the respective cam ramps 218. By aligning the peak portions 214 with the respective cam ramps 218, the cam ring 176 is axially moved in the inward direction (arrow 224), and then the cam ring 176 axially moves the spline ring 46' in the inward direction (arrow 224) to the connection lock position (FIGS. 14 and 15), engaging the spline ring 46' with the rocker clutch 100' between the shift ring 168 and the side gear 38'. The engagement of the cutter clutch 52' is maintained between the spline ring 46' and the gear nest 36' while the spline ring 46' is repositioned to engage the rocker clutch 100'. When the spline ring 46' is in the connection lock position (FIGS. 14 and 15), the spline ring 46' allows torque to be transmitted from the ring gear 16 through the spline ring 46' and the cutter clutch 52' to the gear nest 36', and also allows torque to be transmitted from the ring gear 16 through the spline ring 46' and the rocker clutch 100' to the side gear 38'. After the cutter / rocker 10' is in the connection lock state, the actuator 166 maintains the motor 170 at a second predetermined rotational position, which holds the cutter clutch 52' in an engaged state and holds the rocker clutch 100' in an engaged state.

[0054]

[0068] The actuator 166 may be configured to be monostable such that the motor 170 is held at a first predetermined rotational position to maintain the cutter / rocker 10' in the connected and locked state. Since the peak portion 214 is inclined, the actuator 166 is monostable in the connected and locked state. Therefore, when the cutter / rocker 10' is in the connected and locked state and the motor 170 is deactivated, the return spring 58' drives the motor 170 in reverse due to the inclination at the peak portion 214. Accordingly, the cutter / rocker 10' is maintained in the connected and locked state while the actuator 166 supplies power to the motor 170, and the cutter / rocker 10' is automatically returned to the unlocked state by the return spring 56' when the motor 170 is deactivated.

[0055]

[0069] Referring to FIGS. 14 and 15, in order to engage and disengage the rocker clutch 100' while maintaining the engagement of the cutter clutch 52', the actuator 166 deactivates the motor 170. After the motor 170 is deactivated, the return spring 58' drives the motor 170 in reverse, and the motor 170 drives the drive gear 172 in the reverse rotation direction 220' to drive the sector gear 174 and the attached cam actuator 182 in the second rotation direction 222'. The forward rotation direction 220 and the reverse rotation direction 220' are opposite rotation directions. Similarly, the first rotation direction 222 and the second rotation direction 222' are opposite rotation directions. The cam actuator 182 is rotated in the second rotation direction 222' until the intermediate portion 210 of the cam lobe 190 is circumferentially aligned with the respective cam ramps 218 of the cam ring 176. The return spring 58' axially moves the cam ring 176, the inner thrust ring 178, and the spline ring 46' in the outward direction (arrow 224') to the connection unlock position (FIGS. 12 and 13), thereby moving the spline ring 46' to the connection unlock position for disengaging the rocker clutch 100' while maintaining the cutter clutch 52' in the engaged state. When the spline ring 46' is in the connection unlock position, torque is allowed to be transmitted from the ring gear 16 through the spline ring 46' and the cutter clutch 52' to the gear nest 36' while allowing the side gear 38' to rotate relative to the gear nest 36'. After the cutter / rocker 10' is in the connection unlocked state, the actuator 166 selectively activates the motor 170, which holds the motor 170 in the first predetermined rotational position, holds the cutter clutch 52' in the engaged state, and holds the rocker clutch 100' in the disengaged state.

[0056]

[0070] Referring to FIGS. 12 and 13, in order to engage and disengage the cutter clutch 52' between the spline ring 46' and the gear nest 36' while the rocker clutch 100' is engaged and disengaged, the actuator 166 deactivates the motor 170, which allows the return spring 58' to drive the motor 170 in reverse and drive the drive gear 172 in the reverse rotation direction 220' to rotate the sector gear 174 and the attached cam actuator 182 in the second rotation direction 222'. The cam actuator 182 is rotated in the second rotation direction 222' until the base portion 212 of the cam lobe 190 is circumferentially aligned with the respective cam ramps 218 of the cam ring 176. In response to the rotational repositioning of the base portion 212 of the cam lobe 190 to align with the cam ramp 218, the return spring 58' axially moves the cam ring 176, the inner thrust ring 178, and the spline ring 46' in the outward direction (arrow 224') to the cutter unlock position (FIGS. 7 and 11), moving the spline ring 46' to the cutter unlock position to disengage the cutter clutch 52' between the spline ring 46' and the gear nest 36', thereby allowing the gear nest 36' to rotate freely relative to the ring gear 16. After the cutter / rocker 10' is in the cutter unlock state, the actuator 166 maintains the motor 170 in the deactivated state, which holds the cutter clutch 52' in the disengaged state and holds the rocker clutch 100' in the unlocked state.

[0057]

[0071] A third embodiment of the cutter / rocker 10' using common parts designated by common reference numerals is shown in FIGS. 10 - 15, where like reference numerals with prime symbols represent elements similar to those described above. In this modified cutter / rocker 10', the actuator 166 is configured to be bistable such that the cutter / rocker 10' is held in its current state until the actuator 166 activates the motor 170 to reposition the cam actuator 182' between the connection unlock state and the connection lock state. Only the significant differences between the embodiments are reflected in the figures and the following description.

[0058]

[0072] Referring to FIG. 10, the cam actuator 182' includes a modified ramp portion 206' on the cam lobe 190', which ramp portion 206' includes an intermediate flat portion 210' and a peak flat portion 214'. The flat portions 210', 214' enable the actuator 166 to be bistable, i.e., the flat portions 210', 214' prevent the return spring 56' from driving the motor 170 in reverse when the motor 170 is deactivated and the disconnector / rocker 10' is in the connection unlock state and the connection lock state, respectively. Further, the modified ramp portion 206' includes a circumferentially extending ramp portion 228 between the intermediate flat portion 210' and the peak flat portion 214'. Further, the ramp portion 206' also includes a circumferentially extending ramp portion 226 between the base portion 212 and the intermediate flat portion 210'.

[0059]

[0073] First, the cutter / rocker 10' is in the cutter unlock state shown in FIGS. 7, 8, and 11. The cutter clutch 52' is disengaged, the rocker clutch 100' is unlocked, the spline ring 46' is in the cutter unlock position, and the base portion 212 of the cam lobe 190' is engaged with the cam ramp 218. To selectively engage the cutter clutch 52' when the cutter / rocker 10' is in the cutter unlock state, the actuator 166 activates the motor 170, and the motor 170 drives the drive gear 172 in the forward rotation direction 220 to rotate the sector gear 174 and the attached cam actuator 182' in the first rotation direction 222. Referring to FIGS. 12 and 13, the cam actuator 182' is rotated in the first rotation direction 222 until the intermediate flat portion 210' of the cam lobe 190' engages with the respective cam ramp 218, and this engagement moves the cam ring 176 axially in the inward direction (arrow 224). The axial movement of the cam ring 176 in the inward direction (arrow 224) axially moves the spline ring 46' to the connection unlock position (FIG. 13) in the inward direction (arrow 224), engaging the spline ring 46' with the cutter clutch 52' between the spline ring 46' and the gear nest 36' and enabling torque to be transmitted from the ring gear 16 through the spline ring 46' to the gear nest 36'.

[0060]

[0074] After the cutter / rocker 10’ is in the connection unlock state, the actuator 166’ stops the motor 170 from operating at a predetermined first rotational position. This first rotational position is such that the cutter clutch 52’ is engaged, the lock clutch 100’ is in the disengaged state, the spline ring 46’ is in the connection unlock position, and the intermediate flat portion 210’ of the cam lobe 190’ is engaged with the cam ramp 218 of the cam ring 176, holding the cutter / rocker 10’ in the connection unlock state. The rocker clutch 100’ is maintained in the disengaged state while the cutter clutch 52’ is engaged because the peak flat portion 214’ of the cam lobe 190’ is separated from the cam ramp 218. The contour of the intermediate flat portion 210’ engaged with the cam ramp 218 prevents the return spring 58’ from driving the motor 170 in reverse while the motor 170 is stopped, which enables the actuator 166 to be bistable in the connection unlock state. Thus, the cutter / rocker 10’ is held in the connection unlock state until the actuator 166 actuates the motor 170 to reposition the cutter / rocker 10’ to one of the connection lock state or the disconnection unlock state.

[0061]

[0075] The cutter / rocker 10’ can be placed in a connection lock state by the actuator 166 when in a connection lock release state by engaging the rocker clutch 100’. Referring to FIG. 14, to engage the rocker clutch 100’, the actuator 166 activates the motor 170, and the motor 170 drives the drive gear 172 in the forward rotation direction 220 to rotate the sector gear 174 and the attached cam actuator 182’ in the first rotation direction 222, engaging the peak flat portions 214’ of the cam lobes 190’ with their respective cam ramps 218. By aligning the peak flat portions 214’ with their respective cam ramps 218, the cam ring 176 is axially moved in the inward direction (arrow 224), and then the cam ring 176 axially moves the spline ring 46’ in the inward direction (arrow 224) to the connection lock position (FIGS. 14 and 15), engaging the spline ring 46’ with the rocker clutch 100’ between the shift ring 168 and the side gear 38’. The engagement of the cutter clutch 52’ is maintained between the spline ring 46’ and the gear nest 36’ while the spline ring 46’ is repositioned to engage the rocker clutch 100’. When the spline ring 46’ is in the connection lock position (FIGS. 14 and 15), the spline ring 46’ allows torque to be transmitted from the ring gear 16 through the spline ring 46’ and the cutter clutch 52’ to the gear nest 36’, and also allows torque to be transmitted from the ring gear 16 through the spline ring 46’ and the rocker clutch 100’ to the side gear 38’. After the cutter / rocker 10’ is in the connection lock state, the actuator 166 deactivates the motor 170 at a second predetermined rotational position, and this second predetermined rotational position holds the cutter clutch 52’ in an engaged state and holds the rocker clutch 100’ in an engaged state. The contour of the peak flat portion 214’ engaged with the cam ramp 218 prevents the return spring 58’ from driving the motor 170 in reverse while the motor 170 is deactivated, which allows the actuator 166 to be bistable in the connection lock state.Accordingly, the cutter / rocker 10' is maintained in the connection locked state until the actuator 166 activates the motor 170 to reposition the cutter / rocker 10' to one of the connection unlock state or the cut unlock state.

[0062]

[0076] Referring to FIGS. 14 and 15, in order to engage and disengage the rocker clutch 100' while maintaining the engagement of the cutter clutch 52', the actuator 166 activates the motor 170, and the motor 170 drives the drive gear 172 in the reverse rotation direction 220' to drive the sector gear 174 and the attached cam actuator 182' in the second rotation direction 222'. The cam actuator 182' is rotated in the second rotation direction 222' until the intermediate flat portion 210' of the cam lobe 190' is circumferentially aligned with the respective cam ramps 218 of the cam ring 176. The return spring 58' axially moves the cam ring 176, the inner thrust ring 178, and the spline ring 46' in the outward direction (arrow 224') to the connection unlock position (FIGS. 12 and 13), moving the spline ring 46' to the connection unlock position for disengaging the rocker clutch 100' while maintaining the cutter clutch 52' engaged. When the spline ring 46' is in the connection unlock position, torque is enabled to be transmitted from the ring gear 16 through the spline ring 46' and the cutter clutch 52' to the gear nest 36', while allowing the side gear 38' to rotate relative to the gear nest 36'. After the cutter / rocker 10' is in the connection unlock state, the actuator 166 deactivates the motor 170, which holds the motor 170 in the first predetermined rotational position, holds the cutter clutch 52' engaged, and holds the rocker clutch 100' disengaged. The contour of the intermediate flat portion 210' engaged with the cam ramp 218 prevents the return spring 58' from driving the motor 170 in reverse while the motor 170 is deactivated, which allows the actuator 166 to be bistable in the connection unlock state.

[0063]

[0077] Referring to FIGS. 12 and 13, in order to disengage the cutter clutch 52' between the spline ring 46' and the gear nest 36' while the rocker clutch 100' is disengaged, the actuator 166 activates the motor 170, and the motor 170 drives the drive gear 172 in the reverse rotation direction 220' to rotate the sector gear 174 and the attached cam actuator 182' in the second rotation direction 222'. The cam actuator 182' is rotated in the second rotation direction 222' until the base portion 212 of the cam lobe 190' is circumferentially aligned with the respective cam ramp 218 of the cam ring 176. In response to the cam lobe 190' being rotationally repositioned so that the base portion 212 is aligned with the cam ramp 218, the return spring 58' axially moves the cam ring 176, the inner thrust ring 178, and the spline ring 46' in the outward direction (arrow 224') to the cutter unlock position (FIGS. 7 and 11), moving the spline ring 46' to the cutter unlock position that disengages the cutter clutch 52' between the spline ring 46' and the gear nest 36', thereby enabling the gear nest 36' to rotate freely relative to the ring gear 16. After the cutter / rocker 10' is in the cutter unlock state, the actuator 166 deactivates the motor 170, which holds the cutter clutch 52' in the disengaged state and holds the rocker clutch 100' in the unlocked state.

[0064]

[0078] It will be appreciated that the actuator 166 can be configured to be bistable or monostable in both the connection unlock state and the connection lock state. For example, the actuator 166 may be configured to be bistable in the connection unlock state and monostable in the connection lock state by including an intermediate flat portion 210' and an inclined peak portion 214 as part of the lamp portions 206, 206'. In an alternative embodiment, the actuator 166 may be configured to be monostable in the connection unlock state and bistable in the connection lock state by including an inclined intermediate portion 210 and a peak flat portion 214' as part of the lamp portions 206, 206'.

[0065]

[0079] As described above, the differential cutter and rocker assemblies 10, 10' include cutter clutches 52, 52' configured to selectively connect the ring gear 16 to the differential gear nests 36, 36' such that torque can be transmitted from the ring gear 16 through the gear nests 36, 36', pinion gears 32, and side gears 38, 38' to drive the shaft 42. By disengaging and engaging the cutter clutches 52, 52' between the spline rings 46, 46' and the gear nests 36, 36', it becomes possible to stop the rotation of the ring gear 16, differential housings 18, 18', bearings 26, and the remaining portions of the transmissions 12, 12' while the vehicle wheels are rotating. Further, the differential cutter and rocker assemblies 10, 10' include rocker clutches 100, 100' configured to selectively lock the differential housing 18, 18' or the differential cover 20 to one of the side gears 38, 38' to prevent rotation of the side gears 38, 38' relative to the connected differential housing 18, 18' or differential cover 20.

[0066]

[0080] Although the present invention has been described in illustrative terms, it is to be understood that the terminology used is for the purpose of description and not of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. Accordingly, it is to be understood that the invention may be practiced otherwise than as specifically described within the scope of the appended claims.

Claims

1. A differential disconnect and rocker assembly for a vehicle, a fixed housing, a rotatable ring gear rotatably supported by the fixed housing, a pinion gear assembly including a plurality of pinion gears drivably connectable to the ring gear, a plurality of side gears rotatably disposed inside the fixed housing and meshing with the pinion gears so as to rotate together with the pinion gears, a differential housing and a differential cover rotatably supported by the fixed housing, wherein the ring gear rotates together with at least one of the differential housing and the differential cover, and disconnection of the ring gear from the pinion gear assembly enables the ring gear, the differential housing, and the differential cover to stop rotating while the side gears are rotating, a differential housing and a differential cover; a differential disconnect assembly operatively connected between respective surfaces of the ring gear and the pinion gear assembly so as to rotate together when the ring gear, the pinion gears, and the side gears are connected, and operative to disconnect the ring gear from the pinion gear assembly to prevent driving rotation of the ring gear by the pinion gears by cutting off torque transmission between the ring gear and the pinion gears during wheel rotation; a differential disconnect assembly; a differential rocker slidably coupled to one or more of the differential housing and the differential cover and operatively connected to one of the side gears so as to rotate together when one or more of the differential housing and the differential cover and one of the side gears are connected, and operative to operatively disconnect one or more of the differential housing and the differential cover from one of the side gears to enable the one of the side gears to rotate relative to one or more of the differential housing and the differential cover; a differential rocker; A differential disconnect and rocker assembly comprising.

2. The differential housing and the differential cover are supported by the respective bearings on the fixed housing, and the bearings are also enabled to stop rotation while the side gears are rotating. The differential disconnecter - rocker assembly according to claim 1.

3. The pinion gear assembly includes a gear nest that is supported radially and axially by the differential housing and the differential cover. The gear nest can rotate freely with respect to both the differential housing and the differential cover. When the differential disconnecter assembly is actuated to connect and disconnect the torque transmission, it connects the ring gear to the gear nest and disconnects the ring gear from the gear nest. The differential disconnecter - rocker assembly according to claim 1.

4. The differential disconnecter assembly according to claim 3, including a spline ring that can engage and disengage with one or more of the ring gear and the gear nest to respectively connect and disconnect the torque transmission.

5. The spline ring is slidably engaged with the ring gear and is movable between a connection position and a disconnection position. The spline ring engages with the pinion gear assembly when in the connection position and disengages from the pinion gear assembly when in the disconnection position. The differential disconnecter - rocker assembly according to claim 4.

6. The spline ring is movable by an actuator. The differential disconnecter - rocker assembly according to claim 5.

7. The differential disconnecter assembly includes a biasing member for constantly biasing the spline ring to one of the connection position and the disconnection position. The actuator moves the spline ring to the other of the connection position and the disconnection position. The differential disconnecter - rocker assembly according to claim 6.

8. The actuator includes a drive unit fixed and supported on the fixed housing and a drive member axially displaceable for moving the spline ring. The differential disconnecter - rocker assembly according to claim 7.

9. The differential rocker is slidably connected to one of the differential housing and the differential cover, and includes a shift collar that can engage and disengage with one of the side gears to lock or unlock the side gear with one or more of the differential housing and the differential cover. The differential cutter / rocker assembly according to claim 1.

10. The differential cutter / rocker assembly according to claim 9, wherein the shift collar is movable by a rocker actuator.

11. The differential rocker includes a second biasing member for constantly biasing the shift collar to one of a locked position and an unlocked position. The rocker actuator moves the shift collar to the other of the locked position and the unlocked position. The differential cutter / rocker assembly according to claim 10.

12. The differential cutter / rocker assembly according to claim 11, wherein the rocker actuator includes a second drive unit fixedly supported by the fixed housing and a second drive member axially displaceable to move the shift collar.

13. A differential cutter / rocker assembly for a vehicle, comprising: a fixed housing; a rotatable ring gear rotatably supported by the fixed housing; a differential housing rotatably supported by the fixed housing, wherein the ring gear rotates together with the differential housing; a pinion gear assembly including a plurality of pinion gears drivably connectable to the ring gear and a gear nest radially and axially supported by the differential housing and freely rotatable with respect to the differential housing; a plurality of side gears rotatably disposed inside the fixed housing and meshing with the pinion gears so as to rotate together with the pinion gears; A differential disconnect assembly including a spline ring, the spline ring being engageable with and disengageable from one or more of the ring gear and the gear nest such that when the ring gear, the pinion gear, and the side gear are connected, they rotate together, the differential disconnect assembly being operable to operably disconnect the ring gear from the gear nest to prevent driving rotation of the ring gear by the pinion gear by cutting off torque transmission between the ring gear and the pinion gear during wheel rotation, and the disconnection of the ring gear from the pinion gear assembly enabling the ring gear and the differential housing to stop rotating while the side gear is rotating. A differential disconnect assembly. A shift ring fixedly connected to the spline ring and engageable with and disengageable from one of the side gears to respectively lock and unlock the side gear with the gear nest. A differential disconnect and lock assembly comprising the above.

14. The differential disconnect and lock assembly according to claim 13, wherein the shift ring is disengaged from one of the side gears when the spline ring is in the disconnected position, and the shift ring is engageable with and disengageable from one of the side gears to respectively lock and unlock the side gear with the gear nest while the spline ring is engaged with the gear nest and the ring gear.

15. The differential disconnect and lock assembly according to claim 14, further comprising an actuator configured to selectively engage the spline ring with one or more of the ring gear and the gear nest.

16. The differential disconnect and lock assembly according to claim 15, wherein the actuator is configured to engage the shift ring with one of the side gears while the spline ring is engaged with the gear nest and the ring gear.

17. The differential disconnect and lock assembly according to claim 16, wherein the actuator includes a cam ring axially slidable to engage and disengage the spline ring with the gear nest and axially slidable to engage and disengage the shift ring with one of the side gears.

18. The differential cutter - rocker assembly according to claim 17, wherein the actuator includes a cam actuator, and rotation of the cam actuator axially slides the cam ring to engage and disengage the spline ring with the gear nest based on the rotational position of the cam actuator, and engages and disengages the shift ring with one of the side gears.

19. The differential cutter - rocker assembly according to claim 18, wherein the actuator includes a sector gear fixedly connected to the cam actuator and a drive gear meshing with the sector gear, such that rotation of the drive gear rotates the cam actuator by rotating the sector gear, and rotation of the cam actuator axially moves the spline ring by axially moving the cam ring.

20. The differential cutter - rocker assembly according to claim 19, wherein the actuator is fixedly connected to the fixed housing and includes a motor operatively connected to the drive gear to rotate the drive gear.

21. The cam actuator includes a cam lobe having a ramp portion with an intermediate portion spaced between a base portion and a peak portion. The cam ring includes a cam ramp. When the cam actuator is rotated such that the base portion is aligned with and engaged with the cam ramp, the spline ring is disengaged from the gear nest and the shift ring is disengaged from one of the side gears. When the cam actuator is rotated such that the intermediate portion is aligned with and frictionally engaged with the cam ramp, the spline ring is engaged with the gear nest and the shift ring is disengaged from one of the side gears. When the cam actuator is rotated such that the peak portion is aligned with and frictionally engaged with the cam ramp, the spline ring is engaged with the gear nest and the shift ring is engaged with one of the side gears. The differential cutter - rocker assembly according to claim 20.

22. The differential cut-off rocker assembly according to claim 21, wherein the middle portion is a flat portion such that the actuator is bistable when the spline ring is engaged with the gear nest and the shift ring is disengaged from the side gear.

23. The differential cut-off rocker assembly according to claim 21, wherein the middle portion is an inclined portion such that the actuator is monostable when the spline ring is engaged with the gear nest and the shift ring is disengaged from the side gear.

24. The differential cut-off rocker assembly according to claim 21, wherein the peak portion is a flat portion such that the actuator is bistable when the spline ring is engaged with the gear nest and the shift ring is engaged with one of the side gears.

25. The differential cut-off rocker assembly according to claim 21, wherein the peak portion is an inclined portion such that the actuator is monostable when the spline ring is engaged with the gear nest and the shift ring is engaged with the side gear.

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