Constant velocity joint with disconnection capability

Abstract

A constant velocity joint assembly comprises an input shaft and an output shaft. The constant velocity mechanism enables power transmission between the input shaft and the output shaft while allowing for angular changes between the shafts. A disconnection mechanism is also provided, having a first part and a second part which are capable of relative rotation to each other in the disconnected state but are not capable of relative rotation to each other in the connected state. An actuator causes the disconnection mechanism to transition between the disconnected state and the connected state, thereby transmitting power between the input shaft and the output shaft in the connected state and not transmitting power between the input shaft and the output shaft in the disconnected state. At least one bearing may be interposed between the first part and the second part.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims priority based on U.S. Provisional Application No. 63 / 468,705, filed on May 24, 2023, and the entire content thereof is incorporated herein for all purposes.

[0002] The present invention generally relates to constant velocity joints.

Background Art

[0003] Mechanisms for selectively engaging and disengaging a drive shaft from a corresponding vehicle wheel are known. For example, the basic concept may include mechanisms where multiple drive shafts are continuously or constantly utilized in a drive system. For various reasons, drive systems that may engage or disengage additional drive shafts as needed or desired have been gaining popularity in recent years. For example, known mechanisms allow a user to manually engage the vehicle's drive system to the wheel, which typically requires the user to get out of the vehicle to achieve manual engagement. In addition, automated systems are known, where the vehicle's control system automatically engages or disengages the drive system to / from the wheel depending on the driving conditions. However, such mechanisms often include many complex components and can thus be complex and costly to manufacture and maintain.

[0004] The present invention recognizes and addresses the considerations of prior art configurations and methods.

Summary of the Invention

[0005] One aspect of the present invention provides a constant velocity joint assembly comprising an input shaft and an output shaft. The constant velocity mechanism enables power transmission between the input shaft and the output shaft while allowing angular changes between the shafts. Also provided is a disconnection mechanism having a first part and a second part which are capable of relative rotation to each other in the disconnected state but are not capable of relative rotation to each other in the connected state. An actuator causes the disconnection mechanism to transition between the disconnected state and the connected state, thereby transmitting power between the input shaft and the output shaft in the connected state and not transmitting power between the input shaft and the output shaft in the disconnected state. At least one bearing may be interposed between the first part and the second part.

[0006] In some exemplary embodiments, the constant velocity mechanism has an outer housing that receives a shaft carrying a plurality of trunnions, and the first and second parts are associated with the outer housing. At least a portion of the first part and at least a portion of the second part may be concentric with each other. The first part may have an axial extension integral with the outer housing, and the second part may be concentric with the axial extension. Alternatively, the first and second parts may be axially aligned with each other.

[0007] According to some exemplary embodiments, the disconnection assembly may include a clutch mechanism that causes selective coupling between a first part and a second part. The clutch mechanism itself may include a sliding collar that is slidable on the second part between a disconnected state and a connected state. An axially movable link mechanism may engage with the sliding collar. The clutch mechanism may further include a linear actuator that causes axial movement of the link mechanism and therefore the sliding collar.

[0008] In some exemplary embodiments, the linear actuator may include a screw-type actuator.

[0009] In some exemplary embodiments, the linear actuator may include a solenoid, such as a bistable solenoid.

[0010] Another aspect of the present invention provides a constant velocity joint assembly comprising an input shaft and an output shaft. The constant velocity mechanism enables power transmission between the input shaft and the output shaft while allowing angular changes between the shafts, and the constant velocity mechanism has an outer housing that receives shafts carrying a plurality of trunnions. Also provided is a disconnection mechanism having a first part and a second part which are capable of relative rotation to each other in a disconnected state and are not capable of relative rotation to each other in a connected state. The first part is integral with the outer housing (e.g., part or all thereof), and the disconnection assembly includes a clutch mechanism that causes selective coupling between the first part and the second part. In addition, an actuator causes the disconnection mechanism to transition between a disconnected state and a connected state, thereby transmitting power between the input shaft and the output shaft in the connected state and not transmitting power between the input shaft and the output shaft in the disconnected state.

[0011] The accompanying drawings incorporated herein and constituting part thereof illustrate one or more embodiments of the present disclosure and, together with the description, help to illustrate the principles of the present disclosure.

[0012] A complete and implementable disclosure of the present invention, including the best mode of the invention directed to those skilled in the art, is described herein with reference to the accompanying drawings. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic diagram of a half-shaft assembly using conventional technology. [Figure 2] This is a magnified view of one of the constant velocity joints (CVJs) of the half-shaft assembly shown in Figure 1. [Figure 3] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 4]This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 5] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 6] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 7] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 8] Figure 7 is a diagram of an embodiment that further illustrates an actuator for moving the CVJ axially between a connected state and a disconnected state. [Figure 9A] This figure shows the embodiment of Figure 7 in a disconnected state. [Figure 9B] This figure shows the embodiment of Figure 7 in a connected state. [Figure 10] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Figure 11] This is a schematic diagram of a CVJ having disconnection capabilities according to one embodiment of the present invention. [Modes for carrying out the invention]

[0014] The repeated use of reference numerals in this specification and drawings is intended to represent the same or similar features or elements of the invention as described herein.

[0015] Hereinafter, currently preferred embodiments of the present invention will be referenced in detail, with one or more examples shown in the accompanying drawings. Each example is provided for illustrative purposes only, not as a limitation of the present invention. Indeed, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For example, a feature illustrated or described as part of one embodiment may be used in another embodiment to obtain yet another embodiment. Thus, the present invention is intended to encompass such modifications and variations as falling within the scope of the appended claims and their equivalents.

[0016] As background, Figure 1 shows a prior art vehicle half-shaft assembly 10, which may be modified according to the principles of the present invention. The half-shaft 10 includes a first constant velocity joint (CVJ) 12 and a second constant velocity joint (CVJ) 14 near their respective ends. As is well known, CVJs (also called “constant velocity joints”) function to transmit rotation from an input shaft to an output shaft when the angle between the shafts changes within a certain range. In this case, CVJ 12 is considered an “inside” CVJ because it is directly connected to the differential, for example, via a stub shaft 16. CVJ 12 transmits torque to an intermediate axle 18, which acts as an input to CVJ 14. CVJ 14 is considered an “outside CVJ” because it is connected to a driven wheel, for example, via an output stub shaft 20. CVJ12 and 14 have respective boots 22 and 24 extending between their outer housing (or simply “outside”) and the axle 18, which contain a lubricant and allow angular motion while protecting the inside of the CVJ from contaminants in the environment.

[0017] Referring here to Figure 2, the inner CVJ 12 is typically configured as a “plunging CVJ,” meaning it corresponds to axial movement relative to the axle 18. The plunging CVJ has a “tripod” 26 spline-coupled to the axle 18, which extends radially and has three trunnions (such as those shown in 28) spaced 120° apart. Each of the trunnions carries a barrel-shaped roller bearing that interacts with the outer CVJ 32. The shaft 16 extends from the outer 32 as shown. Thus, rotation of the shaft 16 rotates the outer 32, which in turn rotates the tripod 26, and therefore rotates the axle 18. The outer CVJ may also be a tripod CVJ or any other suitable type, but typically not plunging.

[0018] Embodiments of the present invention provide for the selective interruption of the power flow through a CVJ (which can be either a plunging CVJ or a non-plunging CVJ). The joint can be an integral CVJ or a CVJ incorporated into a half shaft. (An example of an application of an integral CVJ may be a propeller shaft). Some embodiments of the present invention utilize the outside of two components that can rotate independently around the same axis when disconnected or rotate together when connected to achieve selective disconnection of power via a CVJ. For example, the two components may be concentric with each other.

[0019] The separation point between the two components outside the CVJ can be in several different positions, and some examples of which are shown in the drawings described later. A clutch mechanism is provided to selectively transmit power between the two. For example, the two components are selectively coupled using the following. · A translational ring splined on one side in the radial direction and selectively splined on the other side in the axial direction · A translational ring splined on one side in the radial direction and selectively splined on the other side in the radial direction · A radially movable flipper that always contacts one side and selectively contacts the other side · Any other suitable clutch device as required or desired A suitable actuator is utilized to move translational or radially movable components such as the following. · A motor, rack, pinion, and fork · A motor, main screw, and fork · A motor, half screw, and fork · A plunger-type solenoid and fork · An annular solenoid and annular armature · Any other suitable linear actuator or other actuator as required or desired In the case of solenoids, bistable solenoids may preferably be used. The solenoid can be made bistable by utilizing a permanent magnet latch system having, for example, a spring-type or retractable pen-type mechanism. These bistable options have the advantage of "failing to state" when power to the actuator is lost. The retractable pen-type mechanism may also operate in conjunction with a motor-driven actuator.

[0020] In this regard, Figure 3 shows a first embodiment of a CVJ112 according to one aspect of the present invention. In this case, the CVJ112 is incorporated into a half-shaft assembly having a stub shaft 116 for connection to a differential and an axle 118 extending to an outer CVJ. The CVJ112 has an outer 132 including a first portion 132a having a bell (or cup) shape with a closed end and an open end. A tripod 126 is received through the open end so as to be located within the bell portion, as shown in the figure. The stub shaft 116 is fixed to a second portion 132b of the outer 132. As can be seen from the figure, the first portion 132a is received by the second portion 132b and is concentric with the second portion. Appropriate bearings, such as bearings 134 and 136, allow relative rotation between the first portion 132a and the second portion 132b when the clutch mechanism is disengaged. A flexible boot 122 extends between the first portion 132a and the axle 118.

[0021] As shown in the figure, the clutch mechanism may interconnect parts 132a and 132b radially, as indicated by 138, or axially, as indicated by 140. Any suitable clutch mechanism may be used. Some examples include parking pawl type, band clutch type, axial synchronizer type, clutch plate type, etc. When parts 132a and 132b are connected (i.e., when the clutch mechanism is engaged), they rotate together.

[0022] Figure 4 shows a second embodiment of the CVJ212 according to one aspect of the present invention. Since the CVJ212 is similar in many respects to the CVJ112, similar elements are indicated by a reference number obtained by adding 100 to the reference number of the CVJ112. However, in this case, the first portion 232a is wider in the axial direction than the first portion 132a, allowing for a wider spacing between bearings 234 and 236. A wider bearing spread may be desirable to provide better system rigidity. In this case, bearing 234 is located in the stepped region 242 of the first portion 232a. The stepped region 242 is formed as an axial extension from the bell portion of the first portion 232a. Radial and / or axial clutches may be provided, as shown in 238 and 240.

[0023] Figure 5 shows a third embodiment of the CVJ312 according to one aspect of the present invention. Since the CVJ312 is similar in many respects to the CVJ212, similar elements are indicated by a reference number obtained by adding 100 to the reference number of the CVJ212. However, in this case, the further axial extension 344 is located inside the stepped region 342 where the bearing 334 is located. The extension 344, which may or may not have a smaller outer diameter than region 342, provides another potential location for the clutch mechanism, as shown in 346.

[0024] Figure 6 shows a fourth embodiment of the CVJ412 according to one aspect of the present invention. Since the CVJ412 is similar in many respects to the CVJ312, similar elements are indicated by a reference number that is 100 greater than the reference number of the CVJ312. However, in this case, the first part 432a has a longer axial extension 444 in which both bearings 434 and 436 are located. Thus, the second part 432b encloses only the extension 444, and not the bell portion of the first part 432a in which the tripod 426 is located. This embodiment may be advantageous in applications where radial space is more restricted. Furthermore, this embodiment allows for further potential locations for radial and / or axial clutch mechanisms, as shown in 448a and 448b.

[0025] Referring here to Figure 7, an additional embodiment of the present invention provides a CVJ 512 in which the release mechanism is located on the inner "plunge" side of the CVJ for packaging and environmental protection. In this regard, the CVJ seal may be moved to the outside of the assembly. As shown, a translational ring (collar) 550 having axial splines in its inner diameter is located on the outer diameter of a second portion 532b having complementary splines. If the shift collar is located inside the drive unit, no additional seal is required. ATF can also be used for lubricating bearings and joints.

[0026] The fixed and offset support of the assembly is shared in this case between a sealed ball bearing 534, which slides into the extension 542 of the second portion 532b. Furthermore, a thrust bearing 536 (here an NRB thrust bearing) may be located between the axially opposing surfaces of portions 532a and 532b. A corrugated spring 552 may be provided to eliminate gaps in the assembly that could cause noise from the disconnected thrust bearing or ball bearing.

[0027] Referring here to Figure 8, the collar 550 is shifted between a disconnected position (Figure 9A) and a connected position (Figure 9B) in this embodiment using a suitable linkage mechanism 554 which is moved axially by a suitable linear actuator 556. In this case, the linkage mechanism 554 is configured as a fork element having an intermediate elongated portion 558. In this case, a curved portion 560, which is approximately semicircular, is located at the distal end of the elongated portion 558. The curved portion 560 is received in an annular channel 562 defined on the outer circumferential surface of the collar 550. Because of this configuration, the collar 550 can rotate with one or both of the input shaft and output shaft (depending on whether it is disconnected or connected), but the linkage mechanism 554 remains rotatably fixed. However, the forward and backward axial movement of the linkage mechanism 554 by the actuator 556 shifts the collar 550 between the connected position and the disconnected position.

[0028] Instead of splines on the first portion 532a, the collar 550 may include, for example, an axial dog that fits into a suitable opening on the flange 558 of the first portion 532a.

[0029] Figure 10 shows an additional embodiment of the CVJ 612 in which the collar 650 has an axial spline or face spline joint between the stub shaft 616 and the outer portion 632a of the CVJ. A ball bearing 634 allows relative rotation in the disconnected state. A suitable actuator is used to cause disconnection and connection.

[0030] Figure 11 shows an additional embodiment of the CVJ712 in which the collar 750 is spline-coupled to the outer surface of the outer portion 732a of the CVJ. The ball bearing 734 allows relative rotation in the disconnected state and maintains alignment in both the disconnected and connected states. A suitable actuator is used to cause disconnection and connection.

[0031] While one or more preferred embodiments of the present invention have been described above, it should be understood by those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention.

Claims

1. A constant velocity joint assembly, Input shaft and output shaft, A constant velocity mechanism that enables power transmission between the input shaft and the output shaft while allowing angle changes between the shafts, A disconnection mechanism having a first part and a second part that can rotate relative to each other when disconnected, and that cannot rotate relative to each other when connected, The disconnection mechanism includes an actuator that causes the disconnection state to transition between the disconnected state and the connected state. As a result, in the connected state, power is transmitted between the input shaft and the output shaft, and in the disconnected state, power is not transmitted between the input shaft and the output shaft. Constant velocity joint assembly.

2. The constant velocity joint assembly according to claim 1, wherein the constant velocity mechanism has an outer housing that receives a shaft carrying a plurality of trunnions, and the first and second portions are associated with the outer housing.

3. The constant velocity joint assembly according to claim 2, wherein at least a portion of the first portion and at least a portion of the second portion are concentric with each other.

4. The constant velocity joint assembly according to claim 3, wherein the first portion has an axial extension integral with the outer housing, and the second portion is concentric with the axial extension.

5. The constant velocity joint assembly according to claim 2, wherein the first portion and the second portion are aligned with each other in the axial direction.

6. The constant velocity joint assembly according to claim 1, wherein the disconnection assembly includes a clutch mechanism that causes selective coupling between the first and second parts.

7. The constant velocity joint assembly according to claim 1, wherein the clutch mechanism includes a sliding collar that is slidable on the second portion between the disengaged state and the engaged state.

8. The constant velocity joint assembly according to claim 6, wherein the clutch mechanism includes an axially movable link mechanism that engages with the sliding collar.

9. The constant velocity joint assembly according to claim 7, wherein the clutch mechanism includes a linear actuator that causes axial movement of the link mechanism, and therefore the sliding collar.

10. The constant velocity joint assembly according to claim 8, wherein the linear actuator comprises a screw-type actuator.

11. The constant velocity joint assembly according to claim 8, wherein the linear actuator comprises a solenoid.

12. The constant velocity joint assembly according to claim 8, wherein the solenoid comprises a bistable solenoid.

13. The constant velocity joint assembly according to claim 1, wherein at least one bearing is interposed between the first part and the second part.

14. A constant velocity joint assembly, Input shaft and output shaft, A constant velocity mechanism that enables power transmission between the input shaft and the output shaft while allowing angle changes between the shafts, wherein the constant velocity mechanism has an outer housing that receives shafts supporting a plurality of trunnions, A disconnection mechanism having a first part and a second part that are capable of relative rotation to each other in a disconnected state and are not capable of relative rotation to each other in a connected state, wherein the first part is integral with the outer housing, and the disconnection assembly includes a clutch mechanism that causes selective coupling between the first part and the second part. The disconnection mechanism includes an actuator that causes the disconnection state to transition between the disconnected state and the connected state. As a result, in the connected state, power is transmitted between the input shaft and the output shaft, and in the disconnected state, power is not transmitted between the input shaft and the output shaft. Constant velocity joint assembly.

15. The constant velocity joint assembly according to claim 14, wherein at least a portion of the first portion and at least a portion of the second portion are concentric with each other.

16. The constant velocity joint assembly according to claim 15, wherein the first portion is formed as an axial extension integral with the bell portion of the outer housing, and the second portion is concentric with the axial extension.

17. The constant velocity joint assembly according to claim 15, wherein the first part and the second part are aligned with each other in the axial direction.

18. The constant velocity joint assembly according to claim 14, wherein the clutch mechanism includes a sliding collar that is slidable on the second portion between the disengaged state and the engaged state.

19. The constant velocity joint assembly according to claim 18, wherein the clutch mechanism includes an axially movable link mechanism that engages with the sliding collar.

20. The constant velocity joint assembly according to claim 19, wherein the clutch mechanism includes a linear actuator that causes axial movement of the sliding collar.

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