Multi-speed electric drive axle using multi-countershaft transmission

Abstract

An actuator assembly configured to be coupled to a multi-speed electric drive axle, the actuator assembly having: an output assembly including an axially movable member configured to be coupled to a multi-speed input portion of the multi-speed electric drive axle; a ball screw having an externally threaded portion; and a coupler attached to the axially movable member, the coupler having an internally threaded hub meshingly engaged with the externally threaded portion of the ball screw such that rotation of the ball screw linearly moves the coupler and the axially movable member.

Description

Technical Field

[0001] This disclosure relates to a multi-speed electric drive axle using a multi-shaft transmission. Background Technology

[0002] This disclosure relates to a multi-speed electric drive axle using a multi-shaft transmission. The multi-speed electric drive axle can use actuator assemblies to control the selection of gears in the multi-shaft transmission. Summary of the Invention

[0003] In one embodiment of this disclosure, an actuator assembly is configured to be coupled to a multi-speed electric drive axle. The actuator assembly includes: an output assembly including an axially movable member configured to be coupled to a multi-speed input portion of the multi-speed electric drive axle; a ball screw having an external threaded portion; and a connector attached to the axially movable member having an internally threaded hub that engages meshingly with the external threaded portion of the ball screw, such that rotation of the ball screw causes linear movement of the connector and the axially movable member.

[0004] In another embodiment of this disclosure, the actuator assembly is configured to be coupled to a multi-speed electric drive axle, the actuator assembly having: an output assembly including an axially movable member configured to be coupled to a multi-speed input portion of the multi-speed electric drive axle; a ball screw having an externally threaded portion; a connector attached to the axially movable member having an internally threaded hub that engages meshingly with the externally threaded portion of the ball screw such that rotation of the ball screw causes linear movement of the connector and the axially movable member; and a bias spring configured to apply a bias force to the multi-speed input portion of the multi-speed electric drive axle to force the multi-speed input portion into a high-speed position.

[0005] In another embodiment of this disclosure, the actuator assembly is configured to be coupled to a multi-speed electric drive axle of a vehicle. The actuator assembly includes: a ball screw having an externally threaded portion; a coupling having an internally threaded hub that engages meshingly with the externally threaded portion of the ball screw, such that rotation of the ball screw causes linear movement of the coupling; an axially movable member configured to be coupled to a multi-speed input portion of the multi-speed electric drive axle and the coupling; and a pivot fork assembly including a first fork member, a second fork member, at least one first pivot pin, a second pivot pin, a pair of connecting pins, and one or more flexible springs. The at least one first pivot pin pivotally connects a first end of the first fork member to the coupling, the second pivot pin pivotally connects the first fork member to the second fork member, the pair of connecting pins pivotally connects the first fork member to the second fork member, and the one or more flexible springs bias the second fork member about the second pivot pin in a first pivoting direction. Attached Figure Description

[0006] 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.

[0007] Figure 1 This is a perspective view of an exemplary electric drive bridge constructed in accordance with the teachings of this disclosure; Figure 2 It is along Figure 1 A cross-sectional view taken from line 2-2; Figure 3 yes Figure 1 An exploded perspective view of a portion of the electric drive axle. Figure 3 The gearbox, including the housing assembly, transmission, and differential assembly, is shown in more detail. Figure 4 It is a section taken through the motor shaft of the electric motor. Figure 1 A cross-sectional view of a portion of the electric drive axle; Figure 5 yes Figure 1 A schematic diagram of a portion of the electric drive axle, which Figure 5 The transmission is shown in more detail; Figure 6 yes Figure 1 A three-dimensional view of a portion of the electric drive axle. Figure 6 The transmission is shown in more detail; Figure 7 It is a cross-sectional view of a portion of the transmission taken along the motor axis; Figure 8 It is a 3D diagram of a transmission; Figure 9It is a cross-sectional view of a portion of the transmission taken through the intermediate axis between the motor shaft and the first compound gear; Figure 10 It is an exploded 3D view of the multi-speed input section of the transmission; Figures 11 to 13 yes Figure 7 The amplified portion, Figures 11 to 13 The input shafts of the multi-speed input section of the transmission are shown in the high-speed, neutral, and low-speed positions, respectively. Figure 14 yes Figure 1 A three-dimensional view of a portion of the electric drive axle. Figure 14 A portion of the transmission, including the mounting plate, is shown. Figure 15 This is a cross-sectional view taken through a portion of the electric drive axle. Figure 15 The image shows one of the transmission's countershafts mounted between the mounting plate and a portion of the housing assembly; Figure 16 yes Figure 1 A three-dimensional view of a portion of the electric drive axle. Figure 16 The actuator assembly and parking lock mechanism for operating the multi-speed input section of the transmission are shown in more detail. Figure 17 yes Figure 1 A cross-sectional view of a portion of the electric drive axle. Figure 17 The connection between the actuator assembly and the input shaft is shown; Figure 18 yes Figure 1 A 3D view of the electric drive axle. Figure 18 The actuator assembly is shown in more detail; Figure 19 yes Figure 1 A three-dimensional view of a portion of the electric drive axle. Figure 19 The actuator assembly is shown in more detail. Figure 20 It is a 3D diagram of the parking lock mechanism; Figure 21 yes Figure 1 A three-dimensional view of a portion of the electric drive axle. Figure 21 The parking lock mechanism is shown in more detail; Figure 22 This is a cross-sectional view taken through a portion of the parking lock mechanism. Figure 22 The parking lock plunger assembly is shown in operative association with the guide and parking pawl; Figure 23 This is a perspective view of a portion of another electric drive axle, which has an actuator assembly with an alternative configuration; Figure 24 yes Figure 23 End view of the electric drive bridge; Figure 25 It is along Figure 24 A cross-sectional view taken from line AA; Figure 26 yes Figure 23 An exploded perspective view of a portion of the electric drive axle; Figure 27 yes Figure 25 The amplified portion; Figure 28 This is a contour view of the actuator assembly.

[0008] In the various views shown in the accompanying drawings, corresponding reference numerals denote the corresponding components. Detailed Implementation

[0009] refer to Figure 1 and Figure 2 The exemplary electric drive axle constructed according to the teachings of this disclosure is generally indicated by reference numeral 10. The multi-speed electric drive axle 10 includes several main components or parts, including a housing assembly 12, an electric motor 14, a transmission 16, a differential assembly 18, and a pair of axle shafts 20.

[0010] For details, please refer to the following: Figure 2 and Figure 3 The housing assembly 12 in the provided example accordingly includes a first housing member 30 and a second housing member 32, and includes a pair of shaft tubes 34 in which the half-shaft 20 is rotatably disposed. The housing assembly 12 is configured to bear beam loads, and thus provides a “beam-type” or “rigid” shaft configuration for the multi-speed electric drive axle 10. However, it should be understood that the housing assembly 12 can be configured differently, for example, to use the multi-speed electric drive axle 10 with an independent suspension.

[0011] The first housing member 30 and the second housing member 32 have a "clamshell" configuration and cooperate to define a gearbox having a transmission housing 38 and a differential housing 40, which intersect with the differential housing 40. Each of the first housing member 30 and the second housing member 32 may define a coupling flange 44, a differential bearing housing 46, and a shaft tube housing 48. The first housing member 30 may additionally include a motor housing 50. The coupling flanges 44 may abut against each other and may be secured to each other using threaded fasteners. A gasket or sealant (not shown) may be provided between the first housing member 30 and the second housing member 32 (e.g., the gasket or sealant may be configured to contact adjacent end faces of the coupling flanges 44) such that the first housing member 30 and the second housing member 32 are also sealingly connected to each other. Each differential bearing housing 46 is formed inside an associated one of the first housing member 30 and the second housing member 32, and is configured to receive a differential bearing 54 in the differential bearing housing 46, the differential bearing 54 supporting the differential assembly 18 to rotate about the output axis 58. Each axle tube housing 48 defines an axle tube bore configured to receive an associated one of the axle tubes 34 in the axle tube bore.

[0012] Each of the shaft tubes 34 can be received into an associated one in the shaft tube bore and can be securely coupled to an associated one in the shaft tube seat 48 in any desired manner. In the example shown, the shaft tubes 34 are press-fitted into the shaft tube bores and conventional weld slugs (not specifically shown) are used to suppress axial movement of the shaft tubes 34 relative to the first housing member 30 and the second housing member 32 along the output axis 58 and rotational movement about the output axis 58.

[0013] refer to Figure 4The electric motor 14 can be configured as any type of electric motor and includes a motor housing 64, a stator 66, a rotor 68, and a motor output shaft 72. The stator 66 is received in and fixedly coupled to the motor housing 64, the rotor 68 is received in the stator 66 and is rotatable relative to the stator 66 about a motor axis 70, and the motor output shaft 72 is fixedly coupled to the rotor 68. The motor housing 64 may define a motor bearing housing (not specifically shown) and a seal housing. The motor output shaft 72 may extend along the motor axis 70 through the motor housing 64 and optionally extend into a transmission cavity 38 in the housing assembly 12. The motor output shaft 72 may be hollow and may define a plurality of first internal splines 80. A motor bearing 82 may be received between the motor housing 64 and the motor output shaft 72 and may support the motor output shaft 72 for rotation relative to the motor housing 64 about the motor axis 70. A rotary shaft seal 84 can be mounted on a seal seat and can form a seal between the motor housing 64 and the motor output shaft 72, which prevents fluid from being transferred through the motor shaft bore in the motor housing 64 between the interior of the motor housing 64 and the transmission cavity 38. Fasteners (not specifically shown) can be used to securely connect the motor housing 64 to the motor mount 50 on the first housing member 30. Alternatively, the motor housing 64 can be integrally formed with the first housing member 30. The motor output shaft 72 can extend through or be aligned with the motor shaft bore.

[0014] like Figure 5 and Figure 6 As shown, the transmission 16 in the provided example is a multi-speed transmission, but it should be understood that the transmission 16 can be any type of transmission, including a single-speed transmission. The particular transmission 16 shown includes a mounting plate 90, a multi-speed input portion 92, and a single-speed output portion 94. The mounting plate 90 will be described in more detail below, but for now, the following description is sufficient: the mounting plate 90 is received in the transmission cavity 38, the mounting plate 90 is fixedly coupled to the first housing member 30, and a large portion of the multi-speed input portion 92 is disposed between the first housing member 30 and the mounting plate 90.

[0015] refer to Figure 5 and Figure 7The multi-speed input section 92 includes a first gear 100, a second gear 102, a third gear 104, a first compound gear 106, an input shaft 108, and a connecting sleeve 110. The first gear 100 may have gear teeth in the form of helical gear teeth arranged around a first gear hub 112. The first gear hub 112 is hollow and may define a plurality of second internal spline teeth 114. A bearing 116 is mounted between the first housing member 30 and the first gear hub 112 and supports the first gear 100 for rotation about the motor output axis 58. The second gear 102 may have gear teeth in the form of helical gear teeth arranged around a second gear hub 122. The second gear hub 122 is hollow and may define a plurality of third internal spline teeth 124. A pair of bearings 126 are mounted between the mounting plate 90 and the second gear hub 122 and support the second gear 102 axially and radially about the motor output axis 58. The first gear 100 is disposed between the motor output shaft 72 and the second gear 102 along the motor output axis 58. Alternatively, a portion of the first gear hub 112 may be coaxially received within a portion of the second gear hub 122.

[0016] The third gear 104 may have gear teeth in the form of helical gear teeth arranged around the third gear hub 132. The third gear hub 132 is hollow and may define a plurality of fourth internal spline teeth 134 and a plurality of first end face teeth 135 formed on or in the axial end face of the third gear hub 132, the axial end face of which faces or is adjacent to the second gear 102. Bearings 136a and 136b are used to rotatably support the third gear 104 to rotate about the motor axis 70. Bearing 136a is mounted between the mounting plate 90 and the third gear hub 132, adjacent to the second gear 102, while bearing 136b is mounted between the gearbox and the third gear hub 132, on the axial end of the third gear 104 opposite to the bearing 136a.

[0017] refer to Figure 5 , Figure 8 and Figure 9The first compound gear 106 includes a first countershaft 140, a first intermediate gear 142, and a second intermediate gear 144. The first countershaft 140 may be hollow and supported on opposite sides by a first bearing 146a and a second bearing 146b, respectively, to rotate about a corresponding first intermediate axis 148, which is parallel to the motor axis 70 but offset relative to it (i.e., not coincident). The first bearing 146a may be disposed between a first intermediate bearing seat 150 formed by the first housing member 30 and a first end of the first countershaft 140, while the second bearing 148b may be disposed between a second intermediate bearing seat 152 formed by the mounting plate 90 and a second end of the first countershaft 140 opposite to the first end. The first intermediate gear 142 is fixedly connected to the first countershaft 140 to rotate together with the first countershaft 140 about the first intermediate axis 148, and the first intermediate gear 142 includes gear teeth that mesh with the gear teeth of the first gear 100. The second intermediate gear 144 is fixedly connected to the first countershaft 140 to rotate together with the first countershaft 140 about the first intermediate axis 148, and the second intermediate gear 144 includes gear teeth that mesh with the gear teeth of the second gear 102.

[0018] refer to Figure 7 and Figure 10The input shaft 108 is received coaxially through the first gear hub 112, the second gear hub 122, and the third gear hub 132, and is rotatable about the motor axis 70. The input shaft 108 includes a plurality of first external splines 160, a plurality of second external splines 162, and circumferential ribs 164. The plurality of first external splines 160 are disposed on a first axial end of the input shaft 108, which is located within the motor output shaft 72. The plurality of second external splines 162 are spaced apart from the first external splines 160 along the motor axis 70. The circumferential ribs 164 are disposed between the first external splines 160 and the second external splines 162 along the motor axis 70. A lubrication hole 166 may be formed through the input shaft 108, and a plurality of lubrication channels 168 may be formed through the input shaft 108 to intersect the lubrication hole 166 and extend radially through the input shaft 108 at desired locations. A lubrication nozzle can be received in the axial end of the input shaft 108 adjacent to the third gear 104 and can be configured to distribute pressurized lubricating fluid flow into the lubrication orifice 166. The pressurized lubricating fluid in the lubrication orifice 166 can be passed to the lubrication channel 168 for cooling and / or lubricating various components—such as bearings or sliding interfaces—and optionally for transferring pressurized lubricating fluid to the motor output shaft 72, where pressurized lubricating fluid can be used to cool and / or lubricate various components of the electric motor 14. In the provided example, the lubrication nozzle is mounted to an auxiliary cover that is mounted to the side of the second housing member 32 opposite to the transmission cavity 38, and the lubrication nozzle neither contacts nor is sealed to the input shaft 108.

[0019] Various bearings can be used to provide radial support for the input shaft 108 while allowing the input shaft 108 to move axially along the motor axis 70. In the provided example, a first needle roller bearing 170 is disposed between the first gear hub 112 and a first cylindrical bearing surface formed on the input shaft 108, while a second needle roller bearing 172 is disposed between the third gear hub 132 and a second cylindrical bearing surface formed on the input shaft 108.

[0020] The connecting sleeve 110 can be received coaxially about the input shaft 108 and can rotate relative to the input shaft 108 about the motor axis 70. The connecting sleeve 110 can define a shoulder that can abut a first side of a circumferential rib 164 on the input shaft 108. An inner retaining ring can be received in a groove formed in the connecting sleeve 110 and can abut a second side of the circumferential rib 164 opposite to the side abutted by the shoulder. Thus, translation of the input shaft 108 along the motor axis 70 will cause a corresponding translation of the connecting sleeve along the motor axis 70. The connecting sleeve 110 defines a plurality of third external spline teeth 180 and a plurality of second end face teeth 182. The third external spline 180 engages meshingly with the third internal spline 124 formed on the second gear hub 122, thereby connecting the connecting sleeve 110 to the second gear 102 in a manner that suppresses relative rotation of the connecting sleeve 110 relative to the second gear 102 but allows the connecting sleeve 110 to slide or translate axially relative to the second gear 102.

[0021] The input shaft 108 can be positioned at high speed along the motor axis 70 (e.g., Figure 11 As shown), neutral position (such as...) Figure 12 (as shown) and low-speed position (such as) Figure 13 The input shaft 108 moves between the high-speed position, the neutral position, and the low-speed position. The first external spline 160 on the input shaft 108 engages with the first internal spline 80 on the motor output shaft 72 in each of the high-speed position, the neutral position, and the low-speed position (thereby connecting the input shaft 108 to the motor output shaft 72 so that it can rotate together with the motor output shaft 72 about the motor axis 70).

[0022] When the input shaft 108 is positioned as follows Figure 11 At the high-speed position shown, the first external spline 160 on the input shaft 108 engages only with the first internal spline 80 on the motor output shaft 72, the second external spline 162 on the input shaft 108 engages with the fourth internal spline 134 formed on the third gear 104, and the second end face tooth 182 on the connecting sleeve 110 is spaced apart from and disengaged from the first end face tooth 135 on the third gear 104. Therefore, from the electric motor 14 ( Figure 1 The rotational power output through the motor output shaft 72 is input to the input shaft 108 and transmitted to the third gear 104, thereby powering the electric motor 14. Figure 1 The rotational speed of the gear drives the third gear 104.

[0023] When the input shaft 108 is positioned as follows Figure 12In the neutral position shown, the first external spline 160 on the input shaft 108 engages only with the first internal spline 80 on the motor output shaft 72. The second external spline 162 on the input shaft 108 is spaced apart from and disengaged from the fourth internal spline 134 formed on the third gear 104, and the second end face tooth 182 on the connecting sleeve 110 is spaced apart from and disengaged from the first end face tooth 135 on the third gear 104. Therefore, from the electric motor 14 ( Figure 1 The rotational power output through the motor output shaft 72 is input to the input shaft 108, but is not transmitted to any of the first gear 100, the second gear 102, and the third gear 104.

[0024] When the input shaft 108 is positioned as follows Figure 13 At the low-speed position shown, the first external spline 160 on the input shaft 108 engages both the first internal spline 80 on the motor output shaft 72 and the second internal spline 114 on the first gear 100. The second external spline 162 on the input shaft 108 is spaced apart from and disengaged from the fourth internal spline 134 formed on the third gear 104, and the second end face tooth 182 on the connecting sleeve 110 engages with the first end face tooth 135 on the third gear 104. Therefore, from the electric motor 14 ( Figure 1 The rotational power output through the motor output shaft 72 is input to the input shaft 108 and transmitted to the first gear 100 to drive the first intermediate gear 142. Figure 8 ), thereby providing a first reduction gear. With the first intermediate gear 142 ( Figure 8 The second intermediate gear 144 rotates together with it. Figure 8 The second gear 102 is driven to provide a second reduction gear. Since the connecting sleeve 110 is rotatably connected to the second gear 102 (engaged by the engagement of the third external spline 180 with the third internal spline 124) and the third gear 104 (engaged by the engagement of the second end face tooth 182 with the first end face tooth 135), the third gear 104 rotates at the speed of the second gear 102.

[0025] Refer again Figure 5 and Figure 8 The single-speed output section 94 receives rotational power from the third gear 104 and includes an output gear 200 rotatable about an output axis 58. Optionally, the single-speed output section 94 may include a single-stage multi-stage reduction gear between the third gear 104 and the output gear 200. In the provided example, the single-speed output section 94 includes a pair of second compound gears 210 that provide a two-stage gear reduction for the single-speed output section 94 between the third gear 104 and the output gear 200.

[0026] Each of the second compound gears 210 includes a second countershaft 212, a third intermediate gear 214, and a fourth intermediate gear 216. The second countershaft 212 may be hollow and may be supported on opposite sides by a first bearing 220a and a second bearing 220, respectively, to rotate about a corresponding second intermediate axis 222 parallel to both the motor axis 70 and the output axis 58, but offset (i.e., not coincident) relative to both. The first bearing 220a may be disposed between a first intermediate bearing seat formed by the first housing member 30 and a first end of the second countershaft 212, while the second bearing 220b may be disposed between a second intermediate bearing seat formed by the second housing member 32 and a second end of the second countershaft 212 opposite to the first end. The third intermediate gear 214 is fixedly connected to the second countershaft 212 to rotate together with the second countershaft 212 about the second intermediate axis 222, and the third intermediate gear 214 includes gear teeth that mesh with the gear teeth of the third gear 104. The fourth intermediate gear 216 is fixedly coupled to the second countershaft 212 to rotate together with the second countershaft 212 about the second intermediate axis 222, and the fourth intermediate gear 216 includes gear teeth that mesh with the gear teeth of the output gear 200. In the provided example, the second compound gear 210 is arranged along the second intermediate axis 222 such that the third intermediate gear 214 is positioned further away from the first gear 100 than the fourth intermediate gear 216. This configuration allows the transmission 16 to be relatively compact in the axial direction (e.g., along the output axis 58).

[0027] refer to Figure 5 and Figure 8The differential assembly 18 may include a differential input member 230 and a pair of differential output members 232. The differential input member 230 is coupled to an output gear 200 to rotate with the output gear 200, and the differential output members 232 are rotatable relative to the differential input member 230 about an output axis 58. The differential assembly 18 may be configured in any desired manner. For example, the differential assembly 18 may be configured with a bevel gear set having (straight) bevel side gears and a differential pinion, and the differential input member 230 may be a differential housing housing the side gears and the differential pinion. In the provided example, the differential assembly 18 is configured as a planetary or planetary gear train differential assembly having an internal gear (not specifically shown), a sun gear (not specifically shown), a planet carrier (not specifically shown), and multiple sets of planetary gears (not specifically shown). The internal gear may be fixedly coupled to the output gear 200 of the transmission 16 (e.g., integrally and integrally formed with the output gear 200 of the transmission 16). The sun gear is coaxially disposed within the internal gear and is rotatable about the output axis 58. The planet carrier is rotatable about the output axis 58. Each planetary gear set meshes with both the internal gear and the sun gear and includes one or more planetary gears, which are journal-supported by the planet carrier. In the case where the planetary gear set includes two or more planetary gears, each of the planetary gears meshes with another planetary gear, one of the planetary gears meshes with the internal gear, and a different other planetary gear meshes with the sun gear. In the example shown, each planetary gear set includes a first planetary gear and a second planetary gear, the first planetary gear meshing with the internal gear and being journal-supported by the planet carrier, and the second planetary gear meshing with both the first planetary gear and the sun gear and also being journal-supported by the planet carrier. In this configuration, the sun gear and the planet carrier are the differential output member 232 of the differential assembly 18. The differential bearing 54 may be mounted radially between the gearbox and a hub (not specifically shown) formed on the planetary carrier to support the rotation of the differential input member 230 about the output axis 58. In the example shown, the differential bearing 54 is a tapered roller bearing that additionally provides support for the differential assembly 18 in the axial direction along the output axis 58.

[0028] refer to Figure 2 and Figure 5Each of the half-shafts 20 is received through a corresponding one in the axle tube 34 and coupled to rotate together with a corresponding one in the differential output member 232. Various bearings (not specifically shown) can be used to support the half-shafts 20 relative to the housing assembly 12. In the provided example, the multi-speed electric drive axle 10 has a “fully floating” axle configuration in which the half-shafts 20 are rotatably coupled to hubs 250, which are supported (axially and rotatably) on the axle tube 34, such that the half-shafts 20 transmit rotational torque between the differential assembly 18 and the associated vehicle wheels (not shown), but do not bear the weight of the vehicle. However, it should be understood that the multi-speed electric drive axle 10 can be configured differently, and the multi-speed electric drive axle 10 can have any desired configuration (e.g., semi-floating, three-quarter floating, independent).

[0029] refer to Figure 3 , Figure 9 and Figure 14 The mounting plate 90 includes a mounting plate body 260, a flange member 262, a plurality of bearing housings (bearing housing 264a, bearing housing 264b, and a second intermediate bearing housing 152), and a lubrication channel 266. The flange member 262 is fixedly connected to the mounting plate body 260 and extends around the mounting plate body 260. The flange member 262 is configured to abut an inner or inner surface of the first housing member 30. A plurality of threaded fasteners can be received through the flange member 262 and can be threaded into corresponding threaded holes (not specifically shown) in the first housing member 30 to secure the mounting plate 90 to the first housing member 30. Positioning elements such as one or more locating pins or a pair of coiled pins can be used to position or place the mounting plate 90 relative to the first housing member 30. The mounting plate body 260 can be profiled to form a space or cavity that can accommodate the gear teeth of the third gear 104 and the first intermediate gear 142.

[0030] Bearing housing 264a is disposed on a first side of the mounting plate body 260 (i.e., the side facing the first housing member 30) and configured to receive one of the bearings 126 supporting the second gear 102. Bearing housing 164b is disposed on a second opposite side of the mounting plate body 260 (i.e., the side facing the second housing member 32) and configured to receive one of the bearings (i.e., bearing 136a) supporting the third gear 104. A second intermediate bearing housing 152 is formed on the first side of the mounting plate body 260 and configured to receive bearing 146b, which supports the first countershaft 140 of the first compound gear 106.

[0031] refer to Figure 14 and Figure 15The lubrication channel 266 includes an inlet port 270, one or more fluid passages (e.g., fluid passages 272, 274, and 276), and one or more fluid outlets (e.g., outlet nozzle 278 and / or one or more outlet orifices (not specifically shown)). The inlet port 270 is configured to be in fluid communication with a source or flow of pressurized lubricating fluid. In the provided example, the inlet port 270 is in fluid communication with a hose 280 that supplies pressurized lubricating fluid to the lubrication channel 266. The fluid passages are generally configured to allow pressurized lubricating fluid to travel along a path through the mounting plate 90 between the inlet port 270 and the fluid outlets. In the provided example, a first fluid passage 272 receives pressurized lubricating fluid from the inlet port 270 and delivers pressurized lubricating fluid to a second fluid passage 274 and a third fluid passage 276, as well as to the outlet nozzle 278. The outlet nozzle 278 supplies pressurized lubricating fluid to the second intermediate bearing housing 152 (for lubricating both the teeth of the second bearing 146b and the second intermediate gear 144) and to the hollow interior of the first countershaft 140. The pressurized lubricating fluid traveling through the first countershaft 140 can be transferred to the first intermediate bearing housing 150 and used to lubricate both the teeth of the first bearing 146a and the first intermediate gear 142. The outlet orifice can be positioned and sized to provide lubrication in desired areas, such as lubricating the teeth of bearing 146b and / or the third gear 104. Additionally or alternatively, one or more fluid channels in the mounting plate 90 can transfer pressurized lubricating fluid to the first housing member 30, for example, for lubricating various bearings (e.g., the bearing mounted in the first housing member 30 and supporting the second compound gear 210), and / or gear meshing points.

[0032] refer to Figures 16 to 19 The multi-speed input section 92 of the transmission 16 may also include an actuator assembly 300 configured to move the input shaft 108 between a high-speed position, a neutral position, and a low-speed position. The actuator assembly 300 may be configured in any desired manner, but in the particular example provided, it includes an output assembly 302, a lead screw 304, a coupling 306, a first actuator bearing 308 and a second actuator bearing 310, and an actuator motor 312.

[0033] Output assembly 302 may include bearing 320 and axially movable member 322. Bearing 320 may be received on input shaft 108 and abut against a shoulder formed on input shaft 108. Axially movable member 322 may extend between the rotational axis of motor shaft 70 and lead screw 304, and may define bearing bore and coupling seat 330 disposed at opposite ends of axially movable member 322. Bearing 320 is received in bearing bore and may be securely coupled to axially movable member 322 in any desired manner. In the provided example, an inner retaining ring is mounted in a retaining ring groove formed coaxially with bearing bore b4 in axially movable member 322, and the retaining ring groove is formed at the axial end of bearing 320 opposite to the axial end of the shoulder adjacent to the input shaft 108. Therefore, the axially movable member 322 is connected to the input shaft 108 in a manner that suppresses relative axial movement between the axially movable member 322 and the input shaft 108 but allows the input shaft 108 to rotate relative to the axially movable member 322.

[0034] The lead screw 304 is rotatably disposed around the lead screw axis and includes a lead screw input portion 340 and an external thread portion 342.

[0035] The connector 306 may have an internally threaded hub 350 and a mounting flange 352, which can be mounted to the connector seat 330. The internally threaded hub 350 may be threaded onto the externally threaded portion 342 of the lead screw 304. It should be understood that the mounting flange 352 and the connector seat 330 can be configured in any desired manner. In the provided example, the mounting flange 352 has a non-circular cross-sectional area (taken perpendicular to the longitudinal axis of the internally threaded hub 350), and the connector seat 330 defines a groove in which a portion of the mounting flange 352 is received, such that the mounting flange 352 is axially and non-rotatably coupled to the connector seat 330. Therefore, rotation of the lead screw 304 causes a corresponding translation of both the connector 306 and the output assembly 300.

[0036] The first bearing 308 and the second bearing 310 can be installed in the gearbox and can support the lead screw 304 to rotate around the lead screw axis.

[0037] The actuator motor 312 is configured to provide rotational power to drive the lead screw 304 to rotate about the lead screw axis. The actuator motor 312 can be directly coupled to the lead screw input, or a reduction gear, such as a reduction gear set, can be provided between the actuator motor 312 and the lead screw input. In the provided example, a reduction gear set utilizing bevel gears is employed. More specifically, the reduction gear set includes an actuator input gear 360 and an actuator output gear 362. The actuator input gear 360 is directly driven by the actuator motor 312 to rotate about an axis perpendicular to the lead screw axis, and the actuator output gear 362 meshes with the actuator input gear 360 and is rotatable about the lead screw axis. It should be understood that the reduction gear set can be configured differently, and the use of bevel gears is not required. The actuator output gear 362 can be coupled to the lead screw input in any desired manner. For example, the actuator output gear 362 can be directly coupled to the lead screw input section, so that the lead screw 304 rotates directly with the actuator output gear 362. Alternatively, a torsionally resilient coupling can be used between the actuator output gear 362 and the lead screw input section 340 to provide flexibility between the actuator output gear 362 and the lead screw 304 in one or both rotational directions. In the provided example, the torsionally resilient coupling allows the actuator output gear 362 to rotate even when the input shaft 108 cannot translate (e.g., due to: 1) tooth-to-tooth contact between one set of external splines on the input shaft and one set of internal splines on one of the first or third gears, or tooth-to-tooth contact between the first end face teeth and the second end face teeth; or 2) the magnitude of the torque applied by the input shaft 108, i.e., the magnitude of the torque load).

[0038] refer to Figure 16 and Figures 19 to 22 The parking lock mechanism 400 can be integrated into the multi-speed electric drive axle 10 ( Figure 1 In the provided example, the parking lock mechanism 400 is configured to inhibit the rotation of the third gear 104 to inhibit the differential input member 230. Figure 5 The rotation of the differential output member 232 is suppressed, thereby inhibiting the rotation of the differential output member 232. Figure 5 The parking lock mechanism 400 may include a parking lock gear 402, a pivot pin 404, a parking pawl 406, and a parking lock plunger assembly 408.

[0039] The parking lock gear 402 can be fixedly coupled to the third gear 104 and can define a plurality of parking lock teeth and a plurality of valleys 420, each circumferentially disposed between an associated pair of parking lock teeth. A pivot pin 404 can be fixedly coupled to the second housing member 32. In the provided example, the pivot pin 404 is mounted on a bracket 424, which in turn is mounted to the second housing member 32. The position and orientation of the bracket 424 relative to the second housing member 32 can be controlled in any desired manner. In the provided example, a pair of pins 426 are mounted to the bracket 424 and received in corresponding holes in the second housing member to position the pivot pin 404 in the desired position and inhibit rotation of the bracket 424 relative to the second housing member 32. One or more threaded fasteners can be employed to secure the bracket 424 to the second housing member 32.

[0040] The parking pawl 406 includes a pawl body 430 and a pawl member 432. The pawl body 430 is pivotally mounted on a pivot pin 404, and the pawl member 432 is fixedly connected to the pawl body 430. The pawl body 430 is pivotable relative to the parking lock gear 402 between a first position or locked position and a second position or unlocked position. In the first position or locked position, the parking pawl 406 is received in a trough 420, thereby inhibiting rotation of both the parking lock gear 402 and the third gear 104 about the motor axis 70. In the second position or unlocked position, the parking pawl 406 is disengaged from the parking lock gear 402 and does not inhibit rotation of the parking lock gear 402 about the motor axis 70. The parking pawl 406 may optionally include a guide structure 438, which can be mounted to the second housing member 32. The guide structure 438 may have a guide member that guides the pawl body 430 as it moves between a first position and a second position. Movement of the guide structure 438 caused by a corresponding movement of the plunger 450 can cause a corresponding pivoting movement of the pawl body 430 about the pivot pin 404.

[0041] A biasing spring, such as torsion spring 440, can be used to bias the pawl body 430 to a second position. In the provided example, torsion spring 440 has a helical coil portion that is received on pivot pin 404 and disposed between two arms. The end of the first arm is mounted to bracket 424, while the end of the other arm is mounted to pawl body 430. Features such as heads or washers can be formed on or coupled to pivot pin 404 to lock the helical coil portion of torsion spring 440 on the side of bracket 424 opposite to the parking pawl 406 onto pivot pin 404.

[0042] The parking lock plunger assembly 408 may include a plunger 450, an input member 452, and a flexible spring 454. The plunger 450 is movable along an axis parallel to the motor axis 70 and has a generally cylindrical first plunger portion, a generally cylindrical second plunger portion, and a tapered transition portion between the first and second plunger portions. The first plunger portion has a first diameter, the second plunger portion is spaced apart from the first plunger portion and has a second, larger diameter, and the transition portion is disposed between the first and second plunger portions and tapers between them, such that the transition portion has a truncated conical outer surface. The plunger 450 is translatable between a first plunger position in which the first plunger portion contacts the parking pawl 406, and in the second plunger position in which either the transition portion or the second plunger portion contacts the parking pawl 406. The first plunger portion is sized such that when the first plunger portion engages (directly contacts) the pawl body 430, the pawl body 430 of the parking pawl 406 is positioned in a second position. Translation of the plunger 450 from the first plunger position to the second plunger position causes a relatively larger portion of the plunger 450 to contact the pawl body 430, which causes the pawl body 430 to pivot toward the second pawl position.

[0043] The input member 452 is movable about the translational axis of the plunger 450 and can move in any desired manner. In the provided example, the electric parking lock motor 460 and the manual parking lock input lever 462 are configured as alternative or redundant inputs for operating the parking lock mechanism 400, while an output lever 464 is used to coordinate the movement of the input member 452. More specifically, the output lever 464 is coupled to the input member 452 and pivotally coupled to the second housing member 32 to move between a first input position and a second input position. The manual parking lock input lever 462 is fixedly coupled to an extension of the output lever 464 that passes through a portion of the second housing member 32 (i.e., such that the manual parking lock input lever 462 is positioned outside the gearbox). Pivoting movement of the manual parking lock input lever 462 about the pivot axis of the output lever 464 causes a corresponding pivoting movement of the output lever 464 about its pivot axis. An electric parking lock motor 460 is mounted to the outer surface of the second housing member 32 and includes an output shaft 470 extending into the transmission housing 38. A center lever 472 is coupled to the output shaft 470 of the electric parking lock motor 460 and is movable between a first center lever position and a second center lever position via the electric parking lock motor 460 and its axis of rotation about the output shaft 470. The end of the center lever 472 opposite to the output shaft 470 includes a pin that is received in a slotted hole in the output lever 464. Movement of the center lever 472 from the first center lever position to the second center lever position (in response to rotation of the output shaft 470) causes the output lever 464 to pivot about its axis of rotation from the first input position to the second input position. The slotted hole in the output lever 464 allows the output lever 464 to move about its axis of rotation from the first input position to the second input position without a corresponding movement of the center lever 472.

[0044] A flexible spring 454 is disposed between the input member 452 and the plunger 450, and allows the pawl body 430 to push the plunger 450 away from the pawl body 430 when the output lever 464 is in the second input position. It should be understood that placing the output lever 464 in the second input position places the input member 452 in a position that would normally position the plunger 450 in the second plunger position. However, if the pawl member 432 cannot fall into or remain in the valley 420, the parking pawl 406 can translate the plunger 450 toward the flexible spring 454 to compress the flexible spring 454, allowing the parking lock gear 402 to rotate.

[0045] Most of both the actuator assembly 300 and the parking lock mechanism 400 can be assembled to the second housing member 32 before the second housing member 32 is assembled to the first housing member 30 to enclose the transmission chamber 38 and the differential chamber 40. In this regard, all or part of the reduction gear set of the actuator assembly 300 (e.g., actuator input gear 360 and actuator output gear 362 in the provided example), bearings 308 and 310, lead screw 304, torsional elastic coupling (if included), and optionally coupling 306 and / or actuator motor 312 can be installed to the second housing member 32 before the second housing member 30 is installed to the first housing member 30. Additionally or alternatively, all components of the parking lock mechanism 400 except for the parking lock gear 402 can be assembled to the second housing member 32 before the second housing member 32 is installed to the first housing member 30.

[0046] refer to Figures 23 to 27 An alternative actuator assembly 300a is shown. Actuator assembly 300a is configured to move input shaft 108 between a high-speed position, a neutral position, and a low-speed position, but is configured to provide a small amount of flexibility during gear shifting, as will be explained in more detail below, and actuator assembly 300a allows biasing of input shaft 108 toward the high-speed position in the event of a power interruption to actuator assembly 300a. Actuator assembly 300a may include output assembly 302a, ball screw 304a, connector 306a, first actuator bearing 308 and second actuator bearing 310, and actuator motor (not specifically shown). Except as described below, ball screw 304a and connector 306a may be generally similar to lead screw 304 and connector 306 described above. However, it should be understood that the ball screw 304a and the connector 306a define the outer guide and the inner guide respectively, and a plurality of spherical balls are disposed between the outer guide and the inner guide. The rotation of the ball screw 304a will cause the connector 306a to move linearly along the axis of the ball screw 304a.

[0047] Output assembly 302a may include bearing 320, axially movable member 322a, and pivot fork assembly 500. Bearing 320 may be received (i.e., mounted) on input shaft 108 and may abut against a shoulder formed on input shaft 108. Axially movable member 322a may include sleeve member 322a-1 and one or more connecting elements (not specifically shown) that can be mounted to the outer bearing ring of bearing 320 and can be configured to coaxially surround input shaft 108, the connecting elements connecting sleeve member 322a-1 to input shaft 108 in a manner that allows relative rotation of sleeve member 322a-1 and input shaft 108 but restricts or inhibits relative axial movement of both along motor axis 70. In the provided example, one or more connecting elements are formed of wire having a circular cross-sectional shape and include a semi-circular body (not specifically shown) and a pair of ears (not specifically shown) that are received in a circumferentially extending groove in the input shaft 108. The pair of ears extend radially outward from opposite ends of the semi-circular body through a first connecting element hole formed to pass through a circumferential wall of the sleeve member 322a-1.

[0048] The pivot fork assembly 500 may include a first fork member 510, a second fork member 512, a plurality of first pivot pins 514, second pivot pins 516, a pair of connecting pins 518, and one or more flexible springs 520. The first fork member 510 may define a pair of first pivot pin seats 530, a second pivot pin seat 532, a pair of first connecting pin holes 534, and a first flexible spring seat 536. The second fork member 512 may define a third pivot pin seat 540, a pair of second connecting pin holes 542, a pair of second connecting element holes 544, and a second flexible spring seat 546.

[0049] Each of the first pivot pins 514 can be received through a corresponding one of the first pivot pin seats 530 and can be received in a corresponding first pivot pin hole (not shown) formed in the connector 306a, thereby pivotally connecting the first end of the first fork member 510 to the connector 306a for pivoting about the axis of rotation of the ball screw 304a.

[0050] The second pivot pin 516 can be received through holes (not specifically shown) in the second pivot pin seat 532 and the third pivot pin seat 540, thereby pivotally connecting the first fork member 510 and the second fork member 512 relative to each other for pivotal movement about the longitudinal axis of the second pivot pin 516.

[0051] Each of the connecting pins 518 can be configured to pass through an associated set of first connecting pin holes 534 and second connecting pin holes 542. The connecting pins 518, along with the first connecting pin holes 534 and second connecting pin holes 542, can cooperate to control and limit the pivoting movement of the second fork member 512 about the second pivot pin 516 relative to the first fork member 510 in a first pivoting direction and a second pivoting direction. In the provided example, the first connecting pin hole 534 in the first fork member 510 is circular in shape and configured to engage the connecting pin 518 in an interference fit (e.g., press fit), while the second connecting pin hole 542 in the second fork member 512 is slotted. Therefore, when the second fork member 512 pivots about the second pivot pin 516 relative to the first fork member 510, the connecting pin 518 is able to travel within the slot of the second connecting pin hole 542.

[0052] The second connecting element hole 544 can be positioned on the opposite side of the sleeve member 322a-1 and can have a slot shape. The lug of each connecting element can be received through the corresponding one of the second connecting element holes 544. The slot shape of the second connecting element hole 544 allows the second fork member 512 to move relative to the lug of the connecting element when the second fork member 512 pivots about the second pivot pin 516, and allows the second fork member 512 to apply a force to the lug pointing along the motor axis 70.

[0053] One or more flexible springs 520 may be mounted on a first flexible spring seat 536 and a second flexible spring seat 546, and may bias the second fork member 512 about the second pivot pin 516 in a first pivoting direction. The engagement between the connecting pin 518 and the end (upper end) of the groove of the second connecting pin hole 542 may limit the degree to which the second fork member 512 pivots about the second pivot pin 516 relative to the first fork member 510.

[0054] In operation, the ball screw 304a can rotate (i.e., by the rotation of the actuator motor, and if a reduction gear set is included, by the rotation of both the actuator motor and the reduction gear set) to cause the connector 306a to translate along the ball screw 304a. This translation of the connector 306a causes a corresponding pivoting motion of the first fork member 510 about the first pivot pin 514 relative to the connector 304a. Without tooth-to-tooth contact allowing the input shaft 108 to translate freely along the motor axis 70, the second fork member 512 moves with the first fork member 510 about the first pivot pin 514, causing a corresponding translation of the flexible spring 520, which tends to cause a corresponding translation of the connecting element along the motor axis 70, thereby moving the sleeve member 322a-1 and the input shaft 108 along the motor axis 70. If the input shaft 108 cannot move freely along the motor axis 70 (e.g., due to tooth-to-tooth contact or torque locking), the second fork member 512 will not be able to fully pivot with the first fork member 510 about the first pivot pin 514. In this case, relative pivoting motion about the second pivot pin 516 will occur between the first fork member 510 and the second fork member 512, causing corresponding compression of one or more flexible springs 520. The compression of the one or more flexible springs 520 generates a force applied to the input shaft 108 through the second fork member 512 and the axially movable member 322a. This force is maintained until the input shaft 108 can translate along the motor axis 70 to a desired high-speed position, neutral position, or low-speed position associated with the positioning of the coupling 306a along the ball screw 304a. It should be understood that the movement of the input shaft 108 caused by the force applied by one or more flexible springs 520 will cause the second fork member 512 to pivot about the second pivot pin 516 so that the second fork member 512 returns to the "normal" position of the second fork member 512 relative to the first fork member 510.

[0055] A bias spring 550 can be provided to generate a biasing force, which can be applied directly or indirectly to the input shaft 108 to force the input shaft 108 to a high-speed position. In the provided example, the bias spring 550 is a compression spring disposed between the ball screw 304a and the connector 306a. If desired, a thrust washer or bearing 552 can be disposed between the end of the bias spring 550 and one of the associated ball screw 304a and connector 306a. Due to the relatively low friction of the connection between the ball screw 304a and connector 306a, the force applied by the bias spring 550 to the ball screw 304a and connector 306a causes a corresponding rotation of the ball screw 304a relative to the connector 306a, which positions the connector 306a along the ball screw 304a in a position associated with the input shaft 108 being placed in a high-speed position.

[0056] 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. An actuator assembly configured to be coupled to a multi-speed electric drive axle, the actuator assembly comprising: An output component, the output component including an axially movable member configured to be connected to the multi-speed input portion of the multi-speed electric drive bridge; A ball screw having an external threaded portion; A connector attached to the axially movable member, the connector having an internally threaded hub that engages meshingly with the externally threaded portion of the ball screw, such that rotation of the ball screw causes linear movement of the connector and the axially movable member.

2. The actuator assembly of claim 1, wherein, The axially movable member causes the multi-speed input portion of the multi-speed electric drive axle to move parallel to the motor axis of the electric motor that drives the vehicle.

3. The actuator assembly of claim 1, wherein, The multi-speed input section of the multi-speed electric drive bridge includes a first gear and a second gear.

4. The actuator assembly of claim 1, wherein, The multi-speed input section of the multi-speed electric drive axle is the motor shaft of the electric motor that drives the vehicle.

5. The actuator assembly of claim 1, wherein, The axially movable member causes the multi-speed input portion of the multi-speed electric drive axle to move parallel to the motor axis of the electric motor that drives the vehicle.

6. The actuator assembly of claim 1, wherein, The multi-speed input section of the multi-speed electric drive bridge includes a first gear and a second gear.

7. The actuator assembly of claim 1, wherein, The multi-speed input section of the multi-speed electric drive axle is the motor shaft of the electric motor that drives the vehicle.

8. An actuator assembly configured to be coupled to a multi-speed electric drive axle, the actuator assembly comprising: An output component, the output component including an axially movable member configured to be connected to the multi-speed input portion of the multi-speed electric drive bridge; A ball screw having an external threaded portion; A connector attached to the axially movable member, the connector having an internally threaded hub that engages in a meshing manner with the externally threaded portion of the ball screw, such that rotation of the ball screw causes linear movement of the connector and the axially movable member. A bias spring is configured to apply a bias force to the multi-speed input portion of the multi-speed electric drive axle to force the multi-speed input portion into a high-speed position.

9. The actuator assembly of claim 8, wherein, The bias spring is disposed between the ball screw and the connector.

10. The actuator assembly of claim 8, wherein, The bias spring causes the ball screw to rotate relative to the connector.

11. An actuator assembly configured to be coupled to a multi-speed electric drive axle in a vehicle, the actuator assembly comprising: A ball screw having an external threaded portion; A connector having an internally threaded hub that engages in a meshing manner with the externally threaded portion of the ball screw, such that rotation of the ball screw causes the connector to move linearly. An axially movable member is configured to be connected to the multi-speed input portion of the multi-speed electric drive bridge and the connector; A pivoting fork assembly comprising: a first fork member; a second fork member; at least one first pivot pin pivotally connecting a first end of the first fork member to the connector; a second pivot pin pivotally connecting the first fork member to the second fork member; a pair of connecting pins pivotally connecting the first fork member to the second fork member; and one or more flexible springs biasing the second fork member about the second pivot pin in a first pivoting direction.

12. The actuator assembly of claim 11, wherein, A pair of connecting pins restricts the pivoting movement of the first fork member relative to the second fork member.

13. The actuator assembly of claim 11, further comprising a first connecting pin hole receiving one of the connecting pins.

14. The actuator assembly of claim 13, wherein, The first connecting pin hole is circular.

15. The actuator assembly of claim 11, further comprising a second connecting pin hole receiving the connecting pin.

16. The actuator assembly of claim 15, wherein, The second connecting pin hole is a slotted type.

17. The actuator assembly of claim 11, further comprising a bias spring configured to apply a bias force to the multi-speed input portion of the multi-speed electric drive bridge to force the multi-speed electric drive bridge into a high-speed position.

18. The actuator assembly of claim 17, wherein, The bias spring is disposed between the ball screw and the connector.

19. The actuator assembly of claim 17, wherein, The bias spring causes the ball screw to rotate relative to the connector.

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