Wheel drive assembly

Abstract

A wheel drive assembly for transmitting propulsive torque from a source shaft to a wheel, the source shaft receiving torque from a motion actuator. The wheel drive assembly includes a hub adapted to mount the wheel, the hub being arranged about a longitudinal axis adapted to coincide with the axis of rotation of the wheel. The wheel drive assembly also includes a drive axle and a constant velocity (CV) universal joint mounted to the outer end of the drive axle. The CV universal joint connects the drive axle to the hub. The outermost surface of the CV universal joint is disposed outside the outermost surface of the hub along the longitudinal axis.

Description

[0001] Cross-references to related applications

[0002] This patent application claims the benefit of Israel Express application number IL277061, filed on August 31, 2020, which is incorporated herein by reference in its entirety. Invention Field

[0003] This invention relates to vehicle wheel drive systems, and more particularly to a wheel drive assembly that transmits propulsive torque from a source to the vehicle wheels. Background of the Invention

[0005] In most vehicles, propulsive torque from motion actuators (such as electric motors, engines, or transmission gears) is transmitted to the vehicle's wheels using a drive assembly. Typically, each drive assembly transmits torque from motion actuators located on the vehicle chassis to wheels on one side of the chassis.

[0006] Figures 1A and 1B (prior art) are schematic exploded views illustrating a typical drive assembly. As can be seen, a typical drive assembly 10 includes a hub 12 adapted to mount a wheel 14. The wheel 14 typically includes a tire 16 and a rim 18, which is connected to or can be attached to the hub 12, for example, using multiple fasteners such as lug nuts.

[0007] Drive shaft 19 typically extends below the vehicle chassis between the engine and the wheel hubs and generally includes drive axle 20, also referred to as a half-shaft, which is functionally associated with a first constant velocity (CV) universal joint 22 and a second CV universal joint 24. The first CV universal joint 22 (also referred to as the inner CV universal joint) is functionally associated with an input shaft 26 adapted to connect to and receive propulsion torque from the output of a motion actuator. The second CV universal joint 24 (also referred to as the outer CV universal joint) is functionally associated with an output shaft 28, which is connected to or can be connected to the wheel hub 12. Thus, drive axle 20, together with CV universal joints 22 and 24, transmits torque from the motion actuator to the wheel 14 while allowing angular displacement between the axis of rotation of the output shaft of the motion actuator and the axis of rotation of the wheel hub 12. This angular displacement may be caused by the movement of the wheel in various non-rotational directions, such as vertical displacement of the wheel due to uneven road surfaces.

[0008] U.S. Patent Application Publication 2005 / 0257971 discloses a motor-driven wheel comprising a wheel disc, a hub, a steering knuckle, a hub bearing, a constant velocity joint (CV joint), an in-wheel motor, and a spring. The oscillation center of the CV joint is arranged closer to the outer side of the vehicle relative to the hub bearing. Because components of the CV joint, such as the inner race, balls, and cage, are positioned differently from the hub bearing, the diameter of the hub bearing can be reduced. The outer race of the CV joint is integrated with the hub as a single part and has an opening facing the outer side of the vehicle. The large and shallow opening facilitates the installation of the cage, balls, and inner race and their securing with retaining rings. Summary of the Invention

[0009] According to one aspect of some embodiments of the present invention, a wheel drive assembly is provided for transmitting propulsion torque from a source shaft to a wheel, the source shaft receiving torque from a motion actuator, the wheel drive assembly comprising:

[0010] a) A hub adapted to mount the wheel on it, the hub being arranged about a longitudinal axis adapted to coincide with the axis of rotation of the wheel;

[0011] b) Drive axle; and

[0012] c) A constant velocity (CV) universal joint, which is mounted to the outer end of the drive axle and connects the drive axle to the wheel hub.

[0013] The outermost surface of the CV universal joint is disposed outside the outermost surface of the hub along the longitudinal axis of the hub.

[0014] In some implementations, the drive axle includes a half-shaft.

[0015] In some embodiments, the CV universal joint includes a housing and a retainer housed within the housing. In some embodiments, the hub includes a seat on its outer side, and the housing engages the seat. In some embodiments, the housing engages the hub from the outside of the hub.

[0016] In some embodiments, the housing is separable from the hub. In some embodiments, in the use of the CV universal joint, the bearings of the CV universal joint are adapted to rotate about the inner surface of the housing.

[0017] In some implementations, a large portion of the CV universal joint is exposed outside the wheel hub.

[0018] In some embodiments, the wheel drive assembly further includes an inner CV universal joint mounted to the inner end of the drive axle and adapted to be functionally connected to the source shaft.

[0019] According to another aspect of some embodiments of the present invention, a wheel assembly is provided, the wheel assembly comprising:

[0020] As disclosed in this article, the wheel drive assembly; and

[0021] A wheel, comprising a tire and a rim, the rim being mounted on a hub.

[0022] At least a portion of the CV universal joint is visible from the outside of the wheel.

[0023] In some embodiments, the wheel assembly further includes a disc brake and a chuck, wherein at least a portion of the CV universal joint is external to the disc brake.

[0024] In some embodiments, the outermost surface of the CV universal joint extends beyond the center portion of the rim. In some embodiments, the outermost surface of the CV universal joint extends beyond most of the rim. In some embodiments, the outermost surface of the CV universal joint extends beyond the entire rim.

[0025] In some embodiments, the wheel assembly further includes, or is functionally associated with, a steering assembly adapted to steer the wheel hub about a steering pivot point, wherein the steering pivot point does not coincide with the pivot point of the CV universal joint.

[0026] In some embodiments, when the steering assembly turns the wheel hub at a steering angle δ, the CV universal joint oscillates at a swing angle γ, which is smaller than the steering angle δ. In some embodiments, the ratio between the swing angle γ and the steering angle δ is no greater than 1:1.5.

[0027] According to another aspect of some embodiments of the present invention, a vehicle is provided, the vehicle comprising:

[0028] Chassis;

[0029] At least one motion actuator functionally associated with the chassis, the motion actuator having an output shaft; and

[0030] As disclosed in this article, at least one wheel assembly,

[0031] The wheel drive assembly of the at least one wheel assembly is functionally associated with the output shaft of the motion actuator as the source shaft, and the at least one wheel assembly is adapted to transmit propulsion torque from the at least one motion actuator to the wheel of the at least one wheel assembly.

[0032] In some embodiments, the wheel drive assembly further includes an inner CV universal joint mounted to the inner end of the drive axle, the inner CV universal joint being functionally connected to the output shaft of the motion actuator. In some embodiments, the inner CV universal joint is located at the lateral outer edge of the chassis. In some embodiments, the inner CV universal joint is vertically stationary relative to the chassis, while the outer CV universal joint is vertically movable relative to the chassis within a predetermined angular range of the drive axle relative to the chassis.

[0033] In some implementations, the motion actuator is attached to the chassis and serves as a sprung mass.

[0034] According to another aspect of some embodiments of the present invention, a vehicle is provided, the vehicle comprising:

[0035] Chassis;

[0036] At least one motion actuator functionally associated with the chassis, the motion actuator having an output shaft; and

[0037] At least one wheel assembly, the at least one wheel assembly comprising:

[0038] A wheel hub, the wheel hub being arranged around a longitudinal axis;

[0039] Drive axle;

[0040] A constant velocity (CV) universal joint, the CV universal joint being mounted to the outer end of the drive axle, the CV universal joint connecting the drive axle to the wheel hub; and

[0041] A wheel, comprising a tire and a rim, the rim being mounted on a hub such that the longitudinal axis of the hub coincides with the axis of rotation of the wheel.

[0042] The wheel assembly is functionally associated with the output shaft of the motion actuator as the source shaft, and the drive axle and the CV universal joint are adapted to transmit propulsion torque from the at least one motion actuator to the wheel; and

[0043] A steering assembly, functionally associated with the wheel hub and adapted to steer the wheel by pivoting the wheel hub and the wheel about a steering pivot point, wherein the steering pivot point does not coincide with the pivot point of the CV universal joint.

[0044] In some embodiments, when the steering assembly turns the wheel hub at a steering angle δ, the CV universal joint swings at a swing angle γ, which is smaller than the steering angle δ.

[0045] According to yet another aspect of some embodiments of the present invention, a vehicle is provided, the vehicle comprising:

[0046] Chassis;

[0047] At least one motion actuator functionally associated with the chassis, the motion actuator having an output shaft; and

[0048] At least one wheel assembly, the at least one wheel assembly comprising:

[0049] A wheel hub, the wheel hub being arranged around a longitudinal axis;

[0050] Drive axle;

[0051] A constant velocity (CV) universal joint, the CV universal joint being mounted to the outer end of the drive axle, the CV universal joint connecting the drive axle to the wheel hub; and

[0052] A wheel, comprising a tire and a rim, the rim being mounted on a hub.

[0053] The wheel assembly is functionally associated with the output shaft of the motion actuator as the source shaft, and the drive axle and the CV universal joint are adapted to transmit propulsion torque from the at least one motion actuator to the wheel; and

[0054] A steering assembly, functionally associated with the wheel hub and adapted to steer the wheel by pivoting the wheel hub and the wheel about a steering pivot point, wherein the steering pivot point does not coincide with the pivot point of the CV universal joint.

[0055] When the steering assembly causes the wheel hub to turn at a steering angle δ, the CV universal joint swings at a swing angle γ, where the swing angle γ is smaller than the steering angle δ.

[0056] In some implementations, the ratio between the yaw angle γ and the steering angle δ is no greater than 1:1.5.

[0057] In some embodiments, the outermost surface of the CV universal joint is disposed outside the outermost surface of the hub along the longitudinal axis of the hub.

[0058] In some implementations, at least a portion of the CV universal joint is visible from the outside of the wheel.

[0059] In some embodiments, the wheel drive assembly further includes an inner CV universal joint mounted to the inner end of the drive axle, the inner CV universal joint being functionally connected to the output shaft of the motion actuator. In some embodiments, the inner CV universal joint is located at the lateral outer edge of the chassis. In some embodiments, the inner CV universal joint is vertically stationary relative to the chassis, while the outer CV universal joint is vertically movable relative to the chassis within a predetermined angular range of the drive axle relative to the chassis.

[0060] In some implementations, the motion actuator is attached to the chassis and serves as a sprung mass.

[0061] According to another aspect of some embodiments of the present invention, a method is provided for transmitting propulsive torque from a motion actuator having an output shaft of a vehicle to the wheels of the vehicle using a drive shaft, the method comprising:

[0062] Secure the outer CV universal joint of the drive shaft to the outside of the hub;

[0063] Connect the inner CV universal joint of the drive shaft to the output shaft of the motion actuator; and

[0064] Mount the wheel onto the hub.

[0065] After the fastening is performed, the outermost surface of the CV universal joint is positioned outside the outermost surface of the wheel hub.

[0066] In some embodiments, the mounting of the wheel on the hub is performed before the tightening of the outer CV universal joint.

[0067] In some embodiments, the method further includes inserting the outer CV universal joint into the hub from the outer side of the hub before the tightening. In some embodiments, the hub includes an outer seat, and the insertion of the outer CV universal joint includes receiving the outer CV universal joint in the outer seat.

[0068] In some embodiments, the wheel includes a tire mounted on a rim, and the mounting of the wheel on the hub includes fastening the rim to the hub.

[0069] In some embodiments, the outermost surface of the outer CV universal joint extends beyond the center portion of the rim. In some embodiments, the outermost surface of the outer CV universal joint extends beyond most of the rim. In some embodiments, the outermost surface of the outer CV universal joint extends beyond the entire rim.

[0070] In some implementations, the connection of the inner CV universal joint includes placing the inner CV universal joint at the outer edge of the vehicle's chassis.

[0071] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of conflict, this specification, which includes any definitions, shall prevail.

[0072] As used herein, the terms “comprising,” “including,” “having,” and their grammatical variations shall be regarded as referring to the stated feature, integer, step, or component, but do not preclude the addition of one or more additional features, integers, steps, components, or combinations thereof. These terms encompass the terms “consisting of” and “substantially consisting of”.

[0073] As used herein, the term "OR" is a logical operator that combines two Boolean input conditions into a Boolean compound condition such that the compound condition is satisfied if and only if at least one of the two input conditions is satisfied. In other words, if condition C = condition A or condition B, then condition C is not satisfied if neither condition A nor condition B is satisfied, but condition C is satisfied in each of the following cases: (i) condition A is satisfied but condition B is not satisfied, (ii) condition A is not satisfied but condition B is satisfied, and (iii) both condition A and condition B are satisfied.

[0074] As used herein, the term "inner side" indicates that the component of the assembly is located or on one side facing the motion actuator (or the chassis). Conversely, the term "outer side" indicates that the component of the assembly is located or on one side facing the wheel, away from the motion actuator.

[0075] As used herein, the terms "inward" and "inner" refer to the location or side of a component facing or closer to the longitudinal centerline of the vehicle. Typically, components further inward or inner face the vehicle's motion actuators. Conversely, the terms "outward" and "outer" refer to the location or side of a component facing away from or further away from the vehicle's longitudinal centerline. Typically, components further outward or outer face the vehicle's wheels. Attached Figure Description

[0076] This document describes some embodiments of the invention by way of example only, with reference to the accompanying drawings. Reference is now made in particular detail to the drawings, and it should be emphasized that the details shown are illustrative and for the purpose of explaining embodiments of the invention. In this respect, the description taken in conjunction with the drawings will make it clear to those skilled in the art how embodiments of the invention can be practiced. In the drawings:

[0077] Figures 1A and 1B (Prior Art) are schematic exploded diagrams illustrating a typical prior art drive assembly;

[0078] Figure 1C (Prior Art) is a schematic front view representation of a vehicle including the prior art wheel drive assembly shown in Figures 1A and 1B;

[0079] Figure 2 (Prior Art) is a schematic diagram comparing the angular tolerances of drive axles of different lengths;

[0080] Figure 3 It is an exploded perspective view of a wheel drive assembly according to an embodiment of the disclosed technology;

[0081] Figure 4A and Figure 4B These are, respectively, a side view and a cross-sectional view of a wheel hub, which is a part of the wheel drive assembly in Figure 4, according to the implementation scheme of the disclosed technology;

[0082] Figure 5 It is a connection based on the implementation scheme of the disclosed technology. Figure 3 A perspective view of the method of constructing a wheel drive assembly;

[0083] Figure 6A and Figure 6B These are implementation schemes based on the disclosed technology. Figure 3 Front and rear perspective views of the wheel drive assembly. Figure 6B Wheels were added to it;

[0084] Figure 7 yes Figure 3 A partial cutaway perspective view of a wheel drive assembly, the cutaway portion revealing components of a CV universal joint that form part of the wheel drive assembly;

[0085] Figure 8A and Figure 8B yes Figure 3 A cross-sectional view of the wheel drive assembly. Figure 8A yes Figure 8B A close-up view of the central part;

[0086] Figure 9 It includes implementation schemes based on the disclosed technology. Figures 3 to 8B A schematic front view of a vehicle with a wheel drive assembly;

[0087] Figure 10A and Figure 10B The wheels are connected to Figure 4 in two steering scenarios. Figure 8B A schematic side view of the wheel drive assembly; and

[0088] Figure 11 This is a schematic flowchart of a method for transmitting propulsion torque from a vehicle's motion actuator to the vehicle's wheels using a wheel drive assembly employing the technology, according to some embodiments of the disclosed technology. Detailed Implementation

[0089] This invention relates to vehicle wheel drive systems, and more particularly to a wheel drive assembly that transmits propulsive torque from a source to the vehicle wheels.

[0090] Technical aspects solved by the present invention

[0091] In applications such as those using motors positioned close to the wheels, it is desirable to reduce the distance between motion actuators, such as motors or engines, and the wheels. However, even with a reduced distance, there must still be sufficient range of motion between the wheels and the chassis, for example, for vertical movement and / or wheel steering.

[0092] One way to reduce the distance between the motion actuator and the wheel or hub is by shortening the length of the drive axle 20. As explained herein, this approach may be problematic when the CV universal joints 22 and 24 need to compensate for, for example, the angular motion of the drive axle caused by the vertical movement of the wheel relative to the chassis.

[0093] Referring now to Figure 1C (Prior Art), it is a schematic front view representation of a vehicle including the prior art wheel drive assembly shown in Figure 1A. As can be seen, in a typical prior art vehicle 30, the vehicle's motor or engine powertrain 32 is located below the chassis 34. Torque is transmitted from the powertrain 32 to the wheels 14 via the drive axle 20 and wheel hubs 16. In a typical prior art drive assembly, the second (outer) CV universal joint of the drive axle 20 is connected to the inner side of the wheel hub 16 and does not extend into the wheel hub.

[0094] Referring now to Figure 2 (prior art), which is a schematic diagram comparing the angular tolerances of drive axles of different lengths. In Figure 2, it is assumed that a motion actuator (e.g., an electric motor) is fixed to the vehicle chassis. Therefore, the first (inner) CV universal joint 22, fixed to the chassis via the motion actuator, is positioned at a fixed height relative to the vehicle platform (chassis).

[0095] When there is an interference to the wheel (e.g., the wheel enters a pothole), the wheel vertically deflects, causing the second CV joint 24 to move downward. When the wheel vertically deflects by a distance d, the length of the drive axle 20 affects the angular tolerance required for the second CV joint to accommodate the vertical movement of the wheel.

[0096] As can be seen in FIG. 2, when the drive axle 20a has a first length L1 and the distance between the first CV joint 22 and the second CV joint 24a is L1, in order to facilitate the vertical movement of the wheel by a distance d, the drive axle must be set at an angle of x degrees with respect to the horizontal line, and the second CV joint 24a must accommodate said angle. However, when the drive axle 20b is shorter and has a length L2 < L1, the distance between the first CV joint 22 and the second CV joint 24b is L2. In order to facilitate the vertical movement of the wheel by a distance d, the drive axle must be set at an angle of y degrees with respect to the horizontal line, and the second CV joint 24b must accommodate said angle. Assuming that in both cases, the distance d is the same and the drive axle 20a is shorter than the drive axle 20b, then according to basic geometric properties (e.g., the Pythagorean theorem), y > x. Therefore, a greater tolerance is required for the CV joint 24b than for the CV joint 24a.

[0097] Therefore, if the maximum tolerance of the second CV joint is fixed regardless of the length of the drive axle, then compared to a shorter drive axle, a longer drive axle allows the wheel drive assembly to accommodate a greater vertical distance of the wheel's diagonal movement. A system including a shorter drive axle may not have sufficient tolerance to accommodate the angular offset (y) associated with a specific vertical distance, and thus, shortening the drive axle does not provide a suitable solution.

[0098] Therefore, there is a need in the art for a wheel drive assembly that has a small distance between the motion actuator and the wheel while accommodating a sufficient range of motion between the wheel and the chassis, such as for vertical jacking and / or steering of the wheel.

[0099] In addition, the maximum swing angle of the CV joint is usually more restricted than the steering angle of the hub or the wheel. Generally, the steering angle of the wheel depends on the movement of the CV joint, and since the range of the swing angle is usually less than the maximum theoretical steering angle, in practice, the maximum steering angle is limited by the range of the swing angle.

[0100] Therefore, there is a need in the art for a wheel drive assembly in which the steering angle is separated from the swing angle of the CV joint. Alternatively, there is a need in the art for a wheel drive assembly in which the range of the swing angle of the CV joint contributes to a steering angle greater than the swing angle.

[0101] Before explaining at least one embodiment of the invention in detail, it should be understood that the invention is not necessarily limited in its application to the construction details and component arrangements and / or methods set forth in the following description and / or illustrated in the drawings and / or embodiments. The invention can have other embodiments and can be practiced or implemented in various ways.

[0102] Now for reference Figure 3 This is an exploded perspective view of a wheel drive assembly 100 according to an embodiment of the disclosed technology. As can be seen, the wheel drive assembly 100 includes a hub 102 adapted to mount a wheel 104. The wheel drive assembly 100 also includes a drive shaft 105. The drive shaft 105 includes a drive axle 106 functionally associated with: a first (inner) CV universal joint 108 mounted to the inner end of the drive axle; and a second (outer) CV universal joint 110 mounted to the outer end of the drive axle. The first CV universal joint 108 is adapted to connect to the output shaft of a motion actuator, while the second CV universal joint 110 is adapted to connect the drive axle 106 to the hub 102. The drive shaft 105 is configured to transmit propulsion torque from the motion actuator to the wheel.

[0103] Wheel 104 may include rim 112 and tire 114. In some embodiments, wheel covers (not explicitly shown) are attached to the rim to cover other components of the wheel drive assembly, such as the hub and / or CV universal joint.

[0104] In some embodiments, the wheel drive assembly 100 or a wheel assembly including the wheel drive assembly 100 includes wheel braking components such as brake disc 116 and chuck 118.

[0105] In some embodiments, drive shaft 105 may be a standard drive shaft, such as the Rzeppa CV front drive shaft, commercially available from Teraflex Inc., Utah, USA. In some embodiments, drive shaft 105 may be a custom or custom-made drive shaft.

[0106] Now for reference Figure 4A and Figure 4B These are, respectively, a side view and a cross-sectional view of an exemplary wheel hub 102 of a wheel drive assembly 100 according to an embodiment of the disclosed technology.

[0107] As can be seen, the hub 102 includes an annular wall 120 defining a bore 121 and having an inner portion 122 and an outer portion 124 extending therefrom. The inner portion 122 is generally cylindrical, but its outer bore 126 has a larger diameter in the region distal to the wall 120 than in the region proximal to the wall 120. An outer ring 128 surrounds the inner portion 122 such that a ball bearing 130 is disposed between the outer ring 128 and the inner portion 122.

[0108] According to some implementation plans, such as Figure 4A and Figure 4B As shown in the example, the outer portion 124 is a substantially cylindrical, projecting portion extending outward from the annular wall 120. In some embodiments, the diameter of the hole 132 within the outer shroud portion 124 is larger than the diameter of the hole 121. Therefore, the cavity is formed by the outer surface 120a of the wall 120 and the surrounding outer shroud portion 124. As explained in more detail below, surface 120a defines a seat for a portion of the drive shaft 105 disposed within the cavity. The shroud portion 124 terminates at an outward-facing surface 134, which is also the outermost surface of the hub 102.

[0109] In some embodiments, fastener 136 may be provided in wall 120, surrounding its hole 121 to achieve engagement between hub 102 and wheel 104.

[0110] Now for reference Figure 5 It is a perspective view illustrating a method for connecting components of a wheel drive assembly 100 according to an embodiment of the disclosed technology.

[0111] like Figure 5 As can be seen, the drive shaft 105, and more specifically its inner CV universal joint 108, is inserted from the outside of the hub 102 into the hole 132 of the shroud portion 124 of the hub, and moves toward the interior of the hub 102 in the direction of arrow 140, for example, into holes 121 and 126. The drive shaft 105 moves in the direction of arrow 140 until the housing 141 of the outer CV universal joint 110 is disposed within the cavity of the shroud portion 124 and engages with the seat defined by surface 120a. Fastener 142 is used to secure the outer CV universal joint 110 to the surface 120a of the hub 102.

[0112] Now refer to another source Figure 6A and Figure 6B These are, respectively, front and rear perspective views of the wheel drive assembly 100 according to the disclosed technology. Figure 6B Wheel 104 has been added.

[0113] As can be seen, the housing 141 of the outer CV universal joint 110 is disposed within the hub 102, and specifically within its shroud portion 124, such that a portion of the housing, and in some embodiments a large portion thereof, is outside the outermost surface 134 of the hub 102. In other words, a portion of the outer CV universal joint 110, and in some embodiments a large portion thereof, is laterally exposed to the lateral outer side of the hub 102.

[0114] According to some implementation schemes, such as Figure 6A As shown, the outermost surface 144 of the housing 141 is disposed outward relative to the outermost surface 134 of the hub 102, and therefore outward relative to the entire hub 102. In this context, the fastener 136 is not considered as part of forming the hub 102, but rather as a separate component adapted to connect the hub 102 to the wheel 104. As can be seen, the drive axle 106 extends through the hub 102 and extends beyond the hub internally, such that the inner CV universal joint 108 is located entirely within the hub 102.

[0115] In addition, such as Figure 6B As can be seen, a portion of the CV universal joint 110, and in some embodiments the entire CV universal joint 110, is disposed outside the disc brake 116.

[0116] As described herein, the outer CV universal joint 110 is fixedly attached to the hub 102 by fastener 142, and thus the propulsion torque received by the drive axle 106 is transmitted to the hub 102 and the wheel 104 via the CV universal joint 110.

[0117] Now for reference Figure 7 This is a partially cut-away perspective view of the wheel drive assembly 100, the cut-away portion revealing components of the outer CV universal joint 110 of the drive shaft 105 of the wheel drive assembly. See also... Figure 8A and Figure 8B These are cross-sectional views of the wheel drive assembly 100 when connected to wheel 104.

[0118] like Figure 7As can be seen, the outer CV universal joint 110 includes a housing 141, which is fastened to the annular wall 120 of the hub 102 by fasteners 142. A cage 150 of the CV universal joint 110 is disposed within the housing 141, and a retaining clip 152 connects the cage 150 to the drive axle 106 of the drive shaft. Ball bearings of the CV universal joint 110 are adapted to be disposed in the cavity of the cage 150 and rotate against the inner surface of the housing 141. As can be seen, at least a portion of the inner portion 120 of the hub does not extend into it, and this at least portion is not engaged by the CV universal joint 110. As can be seen, the inner end of the CV universal joint 110 is laterally disposed outside the innermost surface of the inner portion 120 (along the longitudinal axis of the hub).

[0119] As can be seen, the housing 141 is positioned adjacent to and abutting against the surface 120a of the annular wall 120, such that a portion of the housing 141, and in some cases a large portion thereof, extends laterally to the outside of the outermost surface 134 of the hub 102. Additionally, a portion of the retainer 150, and in some cases a large portion thereof, extends laterally to the outside of the outermost surface 134 of the hub 102. Figure 5 and Figure 7 As can be seen, the housing 141 of the CV universal joint 110 can be separated from the hub 102. In this context, the term "separable" means that the housing can be separated from the hub while retaining its function as a housing surrounding the retainer 150.

[0120] As described above, a unique feature of some embodiments of the present invention is that the CV universal joint can be separated from the wheel hub and does not need to be integrated with the wheel hub. In some embodiments, this reduces wear between the wheel hub and the CV universal joint, and allows for easy replacement of the CV universal joint when it needs replacement due to wear. Furthermore, some embodiments of the disclosed technology can use "off-the-shelf" standard CV universal joints, and the wheel hub can be designed to accommodate different types and / or sizes of CV universal joints.

[0121] In some embodiments of the disclosed technology, the materials of the hub and the CV universal joint are independent of each other because the hub does not engage with the bearing of the CV universal joint. Therefore, the choice of materials for the hub and the CV universal joint is not constrained by the interaction between the CV universal joint bearing and the hub.

[0122] In some embodiments of the disclosed technology, the drive shaft may be tested independently of the hub or outside the hub, for example, before the drive shaft is installed.

[0123] Turning Figure 8BAs can be seen, the rim 112 includes a center wall portion 160 fastened to the hub 102. An inclined surface 162 extends radially and longitudinally outward from the center wall portion 160 to the end 164 of the rim. A second inclined surface 166 extends radially outward and longitudinally inward from the end 164 of the rim and is adapted to mount a tire on it.

[0124] like Figure 8A As can be seen, the outermost surface 144 of the housing 141 extends laterally beyond the central portion 160 of the rim 112. In some embodiments (such as the embodiment shown), the outermost surface 144 extends beyond most of the rim 112 (in the direction along the axis of rotation of the rim and the wheel), and in some cases, such as in the embodiment shown, it extends beyond the end 164, and thus extends beyond the entire rim 112.

[0125] Now for reference Figure 9 It is a schematic front view representation of a vehicle including a wheel drive assembly 100 according to an embodiment of the disclosed technology. Figure 9 Use similar reference numerals as those in Figure 1C.

[0126] As can be seen, in the vehicle 30' according to the invention, the powertrain 32' of the vehicle's motor or engine is positioned along the outer lateral side of the chassis 34 and fixed to the chassis. Torque is transmitted from the powertrain 32' to the wheels 104 via the drive shaft 105 and the wheel hub 102. As described above, the outer CV universal joint of the drive shaft 105 is disposed outside the wheel hub 102, such that the drive axle extends along the length of the wheel hub. Additionally, the inner CV universal joint of the drive shaft 105 is connected to the powertrain 32' and is therefore disposed at the lateral outer edge of the chassis 34. The inner CV universal joint is fixed to the chassis via the powertrain 32' and is disposed at a fixed height relative to the chassis.

[0127] When there is an disturbance to the wheel (e.g., the wheel enters a pothole), the wheel is vertically offset, causing the outer CV universal joint to move downward relative to the chassis within a predetermined angular range of the drive shaft 105.

[0128] As explained in this article, connecting the drive axle to the lateral outside of the wheel hub while mounting the powertrain on one side of the chassis allows for a reduction in the distance between the powertrain and the wheels, while maintaining the angular range of the wheels and the CV joints.

[0129] A unique feature of this invention is that the arrangement of the drive shaft 105, and especially the mounting of the outer CV universal joint 110 outside the wheel hub 102, compared to the arrangement where the outer CV universal joint is attached to the inner side of the wheel hub, shortens the distance between the wheel hub and the motion actuator. This, in turn, shortens the distance between the outer side of the wheel and the motion actuator, or between the outer side of the wheel and the center of the chassis.

[0130] However, since the drive axle 106 is not shorter than the drive axle in the prior art embodiments, and in fact, the drive shaft 105 can be an off-the-shelf device, the range of angles that the drive shaft must handle is unchanged relative to prior art vehicles using the same drive shaft.

[0131] Therefore, the novel arrangement of the outer CV universal joint, as discussed in this paper, reduces the distance between the wheel and the chassis center or between the wheel and the motion actuator, while solving the problem described above relative to Figure 2.

[0132] Now for reference Figure 10A and Figure 10B These are the wheel connections in two steering scenarios as shown in Figures 4 to 4. Figure 8B A schematic side view of the wheel drive assembly.

[0133] like Figure 10A and Figure 10B As can be seen, wheel 104 is mounted on hub 102. As described above, according to the invention, the outer CV universal joint 110 of drive shaft 105 is connected to hub 102. Hub or wheel is further connected to steering assembly 170, which is adapted to steer hub and wheel about steering pivot point 172. The axis of rotation of wheel is indicated by reference numeral 182.

[0134] exist Figure 10A In this state, the longitudinal axis of the drive shaft 105 coincides with the rotation axis 182.

[0135] exist Figure 10B In this configuration, the steering assembly 170 has rotated the wheel hub 102 and wheel 104 by a steering angle δ. The steering of the wheel 104 at angle δ is supported by the rotational sway angle γ of the drive shaft 105. In other words, in order to maintain the drive shaft 105's drive over the wheel hub 102, the longitudinal axis 184 of the drive shaft 105 relative to its position in the center of the wheel hub 102 is swayed by a sway angle γ. Figure 10A The position of the wheel and the 182-degree swing angle γ relative to the axis of rotation of the wheel.

[0136] A unique feature of this invention is that, due to the novel arrangement of the CV universal joint 110 within the hub 102, the steering angle δ does not need to be equal to the sway angle γ and can be greater than the sway angle. In some embodiments, due to the novel arrangement of the CV universal joint 110 within the hub 102, the steering pivot point 172 does not coincide with the pivot point of the CV universal joint 110 and is located at a certain distance from the pivot point of the CV universal joint. The angular difference between the steering angle δ and the sway angle γ may be attributed to the distance between the steering pivot point and the pivot point of the CV universal joint 110, and / or to the fact that the arrangement of the sway axis around which the drive shaft sway is located differs from the arrangement of the steering axis around which the hub or wheel steering is located.

[0137] In some implementations, the ratio between the yaw angle γ and the steering angle δ is no greater than 1:1.25, 1:1.5, 1:2, 1:2.5, or 1:3. In some example implementations, when the steering angle δ is about 25-35 degrees, the yaw angle γ is about 15-25 degrees.

[0138] Now for reference Figure 11 It is a schematic flowchart of a method for transmitting propulsion torque from a vehicle's motion actuator to the vehicle's wheels using a wheel drive assembly based on some embodiments of the disclosed technology.

[0139] like Figure 11 As can be seen, at step 200, a drive shaft (such as drive shaft 105) will be used. Figure 3 )) CV universal joint 110 ( Figure 3 The outer CV universal joint is fastened to, for example, the hub 102 ( Figure 3 The outer side of the hub. After tightening, the outermost surface of the outer CV universal joint is positioned outside the outermost surface of the hub.

[0140] At step 202, the inner CV universal joint of the drive shaft (such as inner CV universal joint 108) is... Figure 3 The output shaft is connected to the motion actuator, such as the output shaft of a motor or power transmission system. In some implementations (such as...) Figure 9 In the embodiment shown, the connection of the inner CV universal joint includes connecting the inner CV universal joint to the motion actuator at the outer edge of the chassis to which the motion actuator is fixed.

[0141] At step 204, the wheel is mounted to the hub. Therefore, when the motion actuator operates, the drive shaft 105 transmits propulsion torque from the motion actuator to the hub and wheel. In some embodiments, wheel mounting includes fastening the wheel rim to the hub.

[0142] In some implementations, step 204 occurs before step 200 and / or before step 202.

[0143] In some embodiments, at step 208 (which occurs prior to steps 200 and 202), the outer CV universal joint is inserted into the hub from the outer side. In some such embodiments, the inner CV universal joint is slid into an opening in the hub from the outer side, and the inner CV universal joint is moved inward until the outer CV universal joint engages the surface of the hub. Specifically, the inner CV universal joint may be moved until the outer CV universal joint is received in the outer seat of the hub.

[0144] It is anticipated that many related brake actuators and brake control circuits will be developed during the patent expiration period of this application. The scope of the terms brake actuators and brake control circuits is intended to a priori include all such new technologies.

[0145] It should be understood that certain features of the invention described in the context of individual embodiments for clarity may also be provided in combination in a single embodiment. Conversely, various features of the invention described in the context of individual embodiments for brevity may also be provided individually or in any suitable sub-combination, or suitably provided in any other described embodiment of the invention. The various features described in the context of various embodiments should not be considered as essential features of those embodiments unless the embodiments would be invalid without these elements. Although the invention has been described in conjunction with its specific embodiments, it will be apparent to those skilled in the art that many alternatives, modifications, and variations will be readily apparent. Therefore, it is intended to cover all such alternatives, modifications, and variations falling within the spirit and broad scope of the appended claims.

Claims

1. A wheel assembly, comprising: A wheel drive assembly (100) for transmitting propulsion torque from a source shaft (105) to a wheel (104), the wheel (104) including a tire (114) and a rim, the wheel drive assembly including: a) A hub (102) adapted to mount the wheel on it, the hub being arranged about a longitudinal axis adapted to coincide with the axis of rotation (182) of the wheel; b) Drive axle (106); and c) A constant velocity joint (110), which is mounted on the outer end of the drive axle (106) and connects the drive axle (106) to the wheel hub (102). The constant velocity joint (110) includes: Shell (141); and A retainer (150) is disposed within the housing (141). The outermost surface (144) of the housing (141) of the constant velocity universal joint is disposed outside the outermost surface (134) of the hub (102) along the longitudinal axis of the hub (102), and the wheel assembly is configured such that at least one of the first and second conditions is true, and wherein: a. According to the first condition, the outermost surface (144) of the housing (141) of the constant velocity universal joint (110) extends beyond the central portion (160) of the rim (112); and b. According to the second condition, the wheel assembly further includes a steering assembly, or is functionally associated with the steering assembly, the steering assembly being adapted to turn the wheel hub about a steering pivot point, wherein the steering pivot point does not coincide with the pivot point of the constant velocity joint, and the steering assembly turning the wheel hub at a steering angle δ, the constant velocity joint oscillating at an oscillation angle γ, the oscillation angle γ being smaller than the steering angle δ.

2. The wheel assembly of claim 1, wherein the drive axle includes a half-shaft.

3. The wheel assembly of claim 1, wherein the constant velocity universal joint includes a housing and a retainer housed within the housing.

4. The wheel assembly of claim 3, wherein the hub includes a seat on its outer side, and wherein the housing engages the seat.

5. The wheel assembly of claim 3, wherein the housing engages the hub from the outside of the hub.

6. The wheel assembly of claim 1, wherein at least the first condition is true.

7. The wheel assembly as claimed in any one of claims 1-6, wherein, in the use of the constant velocity joint, the bearing of the constant velocity joint is adapted to rotate about the inner surface of the housing.

8. The wheel assembly of any one of claims 1-6, wherein a majority of the constant velocity joint is exposed outside the wheel hub.

9. The wheel assembly as claimed in any one of claims 1-6, the wheel drive assembly further comprising an inner constant velocity joint, the inner constant velocity joint being mounted to the inner end of the drive axle and adapted to be functionally connected to the source axle.

10. The wheel assembly of any one of claims 1-6, further comprising a disc brake and a chuck, wherein at least a portion of the constant velocity joint is external to the disc brake.

11. The wheel assembly as claimed in any one of claims 1-6, wherein at least the second condition is true.

12. The wheel assembly of claim 11, wherein the ratio between the sway angle γ and the steering angle δ is not greater than 1:1.5.

Images