Rear wheel steering and vehicle

Abstract

The utility model discloses a rear wheel steering gear and vehicle relates to vehicle manufacturing technical field, and the rear wheel steering gear includes: steering drag link assembly is used for being connected with knuckle, steering motor, steering screw sleeve and steering screw rod, steering screw sleeve is equipped with in steering screw rod outside and is cooperated with the screw thread of steering screw rod, and steering screw rod is connected with steering drag link assembly, and steering motor is connected with steering screw sleeve power to drive steering screw sleeve rotation, and steering screw sleeve drives steering screw rod axial movement when rotating, and drives knuckle rotation through steering drag link assembly. The rear wheel steering gear of the utility model, through the screw thread cooperation of steering screw sleeve and steering screw rod, to make steering motor can drive steering drag link assembly axial movement through steering screw sleeve and steering screw rod, and then drive knuckle rotation, and can be set up as two rear wheel steering gears and control the left and right rear wheels of vehicle respectively, has higher redundancy security, is not easy to wear and tear, and the maintenance cost is low.

Description

Technical Field

[0001] This utility model relates to the field of vehicle manufacturing technology, and in particular to a rear wheel steering system and a vehicle having the rear wheel steering system. Background Technology

[0002] The rear-wheel steering system of a vehicle includes a steering motor, a transmission mechanism, and a lead screw. The steering motor can drive the lead screw to steer the rear wheels of the vehicle by changing its speed through the transmission mechanism. In related technologies, traditional rear-wheel steering systems drive the left and right rear wheels to steer synchronously, resulting in low redundancy and safety, easy wear, and high maintenance costs. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a rear-wheel steering system that offers high redundancy and safety, is not easily worn, and has low maintenance costs.

[0004] A rear wheel steering system according to an embodiment of the present invention includes: a steering tie rod assembly for connection to a steering knuckle; a steering motor, a steering sleeve, and a steering screw; the steering sleeve is sleeved on the steering screw and threadedly engaged with the steering screw; the steering screw is connected to the steering tie rod assembly; the steering motor is poweredly connected to the steering sleeve to drive the steering sleeve to rotate; when the steering sleeve rotates, it drives the steering screw to move axially, and drives the steering knuckle to rotate through the steering tie rod assembly.

[0005] According to the rear wheel steering system of this utility model embodiment, the steering motor drives the steering tie rod assembly to move axially through the threaded engagement of the steering sleeve and the steering screw, thereby driving the steering knuckle to rotate. It can also be configured as two rear wheel steering systems to control the left and right rear wheels of the vehicle separately, so that the two left and right rear wheels can turn independently, which has higher redundancy and safety, is not easy to wear, and has low maintenance costs.

[0006] The rear wheel steering gear according to some embodiments of the present invention further includes an oil sleeve structure for providing lubricant to the threaded engagement between the steering sleeve and the steering screw.

[0007] According to some embodiments of the present utility model, the rear wheel steering gear includes a steering screw comprising a first rod segment, a threaded segment, and a second rod segment connected in sequence, and a steering sleeve is sleeved outside the threaded segment and threadedly engaged with the threaded segment. The oil sleeve structure includes a first oil sleeve and / or a second oil sleeve, wherein the first oil sleeve is located at one end of the steering screw sleeve near the first rod segment, and the second oil sleeve is located at one end of the steering screw sleeve near the second rod segment.

[0008] According to some embodiments of the present invention, the rear wheel steering gear further includes a steering gear housing, the steering sleeve is rotatably mounted in the steering gear housing, and the steering screw is axially movable in the steering gear housing; The steering gear housing is provided with a limiting member, which is adapted to limit and press against the steering screw when the steering screw moves axially to its maximum position.

[0009] According to some embodiments of the present invention, in the rear wheel steering gear, the limiting member is constructed as a limiting post, which is inserted into the steering gear housing radially along the steering screw, and at least a portion of the limiting post is located on the axial movement trajectory of the steering screw.

[0010] According to some embodiments of the present invention, the rear wheel steering gear further includes a limiting seal, which is sleeved outside the limiting post and is in a sealing and pressing fit with the steering gear housing.

[0011] According to some embodiments of the present invention, the rear wheel steering gear further includes a detection element and a steering controller. The detection element and the steering motor are both electrically connected to the steering controller. The detection element is located outside the steering lead screw and is used to detect the axial position of the steering lead screw. The steering controller and the steering motor are used to control the rotation angle of the steering motor according to the detection result of the detection element.

[0012] According to some embodiments of the present invention, the rear wheel steering gear includes an outer tie rod structure and a lateral tie rod structure. One end of the lateral tie rod structure is ball-jointed with the steering screw, and the other end of the lateral tie rod structure is connected to one end of the outer tie rod structure. The other end of the outer tie rod structure is used to connect to the steering knuckle.

[0013] According to some embodiments of the present invention, in the rear wheel steering gear, a first pulley is provided outside the motor shaft of the steering motor, and a second pulley is provided outside the steering sleeve. The first pulley and the second pulley are driven by a transmission belt.

[0014] This utility model also proposes a vehicle.

[0015] The vehicle according to the present invention includes the rear wheel steering system described in any of the above embodiments.

[0016] The vehicle and the aforementioned rear-wheel steering system have the same advantages over the prior art, which will not be repeated here.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of the rear wheel steering system according to an embodiment of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the rear wheel steering system according to an embodiment of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the steering tie rod assembly according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the detection element according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the limiting member and the limiting seal member according to an embodiment of the present utility model; Figure label: Rear wheel steering gear 100, Steering tie rod assembly 1, outer tie rod structure 11, transverse tie rod structure 12, ball joint 121. Steering motor 2, Steering screw sleeve 3, second pulley 31, Steering screw 4, ball joint 41, first section 42, threaded section 43, second section 44 First oil sleeve 51, Steering gear housing 6, limiting component 61, limiting seal 62, Detection element 7, transmission belt 8. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0021] The following is for reference. Figures 1-5 The rear wheel steering system 100 according to an embodiment of the present invention is described. Each rear wheel steering system 100 can be used to drive a single wheel to turn independently, thereby setting two rear wheel steering systems 100 to control the steering of the left and right rear wheels of the vehicle respectively, which has higher redundancy and safety, is not easy to wear, and has low maintenance costs. like Figure 1 and Figure 2 As shown, the rear wheel steering gear 100 according to an embodiment of the present utility model includes: a steering tie rod assembly 1, a steering motor 2, a steering sleeve 3, and a steering screw 4.

[0022] The steering tie rod assembly 1 is an important component of the vehicle steering system. The rotational motion of the steering wheel can be transmitted to the wheels through the steering tie rod assembly 1, thereby controlling the rotation of the wheels and the direction of travel of the vehicle.

[0023] The steering tie rod assembly 1 is used to connect with the steering knuckle. That is, the steering tie rod assembly 1 can drive the steering knuckle to rotate, thereby driving the wheel to rotate. Specifically, the steering tie rod assembly 1 can perform axial reciprocating motion, thereby driving the steering knuckle connected to it to rotate in two opposite directions, and thus driving the wheel to rotate in two directions. The steering knuckle and the wheel can rotate clockwise or counterclockwise, thereby achieving control of the vehicle's driving direction.

[0024] The steering motor 2 is the power source of the electric power steering system, which makes it easier for the driver to turn the steering wheel. The steering motor 2 can also transmit driving force to the steering tie rod assembly 1, thereby enabling the steering tie rod assembly 1 to perform reciprocating axial movement and control the steering of the wheels.

[0025] Steering sleeve 3 is sleeved outside steering screw 4, and steering sleeve 3 is threadedly engaged with steering screw 4. Steering screw 4 is connected to steering tie rod assembly 1. Steering motor 2 is poweredly connected to steering sleeve 3 so that steering motor 2 drives steering sleeve 3 to rotate. When steering sleeve 3 rotates, it drives steering screw 4 to move axially, and drives steering knuckle to rotate through steering tie rod assembly 1.

[0026] In other words, the threaded connection allows the steering sleeve 3 and the steering screw 4 to convert the rotational motion of the steering motor 2 into the axial motion of the steering tie rod assembly 1. For example, when the steering sleeve 3 rotates, the steering sleeve 3 can drive the steering screw 4 to move axially closer to the steering sleeve 3 or move axially away from the steering sleeve 3 through the threaded connection. Thus, the steering sleeve 3 rotates and the steering screw 4 moves axially, that is, the rotational motion is converted into axial motion through the threaded connection, thereby realizing the control of the wheel steering.

[0027] Specifically, the steering motor 2 can be located above the steering tie rod assembly 1. When the steering motor 2 rotates to make the wheel rotate clockwise, it can drive the steering sleeve 3, which is powered by it, to rotate. The rotation of the steering sleeve 3 then drives the steering screw 4 to move axially, thereby causing the steering screw 4 to drive the steering knuckle to rotate clockwise, thus making the wheel rotate clockwise. When the steering motor 2 rotates to make the wheel rotate counterclockwise, it can drive the steering sleeve 3 to rotate. The steering sleeve 3 then drives the steering screw 4 to move axially to make the wheel rotate counterclockwise, thereby causing the steering screw 4 to drive the steering knuckle to rotate counterclockwise, thus making the wheel rotate counterclockwise.

[0028] Furthermore, the rear wheel steering gear 100 can be configured as two, that is, two rear wheel steering gears 100 can be installed on the vehicle to drive the left and right rear wheels of the vehicle separately. Compared with the traditional rear wheel steering gear 100, it can avoid the two rear wheels rotating synchronously, and can realize the independent control of one rear wheel of the vehicle to rotate, which is conducive to the rear wheel steering gear 100 adapting to different vehicle models and driving environments.

[0029] The steering screw 4 can be constructed as a trapezoidal screw or a ball screw, both of which can achieve threaded engagement with the steering sleeve 3. Simultaneously, an electromagnetic brake can be installed to achieve mechanical self-locking, thereby reducing unintended wheel steering.

[0030] According to the rear wheel steering gear 100 of this utility model embodiment, the steering motor 2 can drive the steering tie rod assembly 1 to move axially through the threaded engagement of the steering sleeve 3 and the steering screw 4, thereby driving the steering knuckle to rotate. It can also be configured as two rear wheel steering gears 100 to control the left and right rear wheels of the vehicle separately, so that the two left and right rear wheels can turn independently, which has higher redundancy safety, is not easy to wear, and has low maintenance cost. In some embodiments, the rear wheel steering system 100 further includes an oil sleeve structure for providing lubricant to the threaded engagement between the steering sleeve 3 and the steering screw 4. That is, the oil sleeve structure can provide lubricant between the steering sleeve 3 and the steering screw 4, thereby ensuring smooth threaded engagement between them and reducing wear.

[0031] Specifically, such as Figure 3 As shown, the rear wheel steering gear 100 is equipped with an oil sleeve structure, which can be sleeved on the steering screw 4. When the steering screw 4 moves axially, the oil sleeve structure can provide lubricant to the steering screw 4. During the axial movement of the steering screw 4, the lubricant can be carried into the threaded engagement between the steering screw 3 and the steering sleeve 3. As the steering sleeve 3 rotates, the lubricant can be evenly distributed between the steering sleeve 3 and the steering screw 4, thereby making the threaded engagement between the steering sleeve 3 and the steering screw 4 smoother, reducing jamming during the movement, and thus smoothly realizing the steering control of the wheel.

[0032] In some embodiments, the steering screw 4 includes a first rod segment 42, a threaded segment 43, and a second rod segment 44 connected in sequence. A steering sleeve 3 is sleeved on the threaded segment 43, and the steering sleeve 3 is threadedly engaged with the threaded segment 43. That is, the threaded segment 43 of the steering screw 4 is threadedly engaged with the steering sleeve 3, so that the axial movement stroke of the steering screw 4 is the distance between the first rod segment 42 and the second rod segment 44. In other words, the movement stroke of the steering screw 4 is the length of the threaded segment 43, thereby preventing the steering sleeve 3 from disengaging from the threaded segment 43, and thus preventing the threaded engagement between the steering sleeve 3 and the threaded segment 43 from failing.

[0033] The oil sleeve structure includes a first oil sleeve 51 and / or a second oil sleeve. The first oil sleeve 51 is located at the end of the steering screw sleeve 3 near the first rod section 42, and the second oil sleeve is located at the end of the steering screw sleeve 3 near the second rod section 44. That is, oil sleeve structures can be provided at both ends of the steering screw 4, so that there can be sufficient lubricant between the threaded section 43 and the steering screw sleeve 3, thereby ensuring smooth thread engagement between the steering screw sleeve 3 and the threaded section 43.

[0034] Specifically, such as Figure 2 and Figure 3As shown, the two ends of the steering screw 4 are a first rod segment 42 and a second rod segment 44, respectively, and the middle area is a threaded segment 43, that is, the threaded segment 43 connects the first rod segment 42 and the second rod segment 44. A first oil sleeve 51 is provided between the first rod segment 42 and the threaded segment 43. The first oil sleeve 51 can provide lubricant to the threaded segment 43 at the end near the first rod segment 42. A second oil sleeve is provided between the second rod segment 44 and the threaded segment 43. The second oil sleeve can provide lubricant to the threaded segment 43 at the end near the second rod segment 44. Thus, both ends of the steering screw 4 can be provided with oil sleeve structures, and the oil sleeve structures can provide lubricant to the steering screw 4, so that the threaded mating area of ​​the steering oil sleeve and the threaded segment 43 can be fully lubricated, thereby enabling the rear wheel steering gear 100 to smoothly control the wheel steering.

[0035] Therefore, a first oil sleeve 51 and a second oil sleeve can be provided at both ends of the steering screw 4. In this way, when the steering screw 4 moves in two opposite directions relative to the steering sleeve 3, there are corresponding oil sleeve structures to provide lubricant, thereby ensuring that the rear wheel steering gear 100 can maintain a smooth rotation state when driving the wheels in two opposite directions, thus ensuring steering efficiency.

[0036] In some embodiments, the rear wheel steering gear 100 further includes a steering gear housing 6, a steering screw sleeve 3 is rotatably mounted in the steering gear housing 6, and a steering screw 4 is axially movable in the steering gear housing 6; wherein, the steering gear housing 6 is provided with a limiting member 61, which is adapted to limit and press against the steering screw 4 when the steering screw 4 moves axially to its maximum position.

[0037] In other words, the steering sleeve 3 and the steering screw 4 can be installed together inside the steering gear housing 6, so that the steering gear housing 6 can protect the steering screw 4 and the steering sleeve 3, avoid external interference with the threaded fit, and prevent the lubricant at the threaded fit from leaking outward, thus ensuring that the steering sleeve 3 and the threaded section 43 are adequately lubricated, thereby ensuring control of wheel steering.

[0038] Furthermore, the limiting member 61 can limit the axial movement stroke of the steering screw 4, thereby enabling the steering tie rod assembly 1 to control the axial movement distance of the steering screw 4, and thus control the wheel angle within a certain range, reducing the risk of overtravel and the risk of damage to the steering system.

[0039] Specifically, such as Figure 2 and Figure 3As shown, the steering sleeve 3 and the steering screw 4 are disposed inside the steering gear housing 6, and the steering sleeve 3 is sleeved outside the steering screw 4, that is, the steering sleeve 3 is disposed between the steering gear housing 6 and the steering screw 4, and a limiting member 61 is correspondingly disposed on the steering gear housing 6. The limiting member 61 is correspondingly disposed with the steering screw 4. When the steering screw 4 and the steering sleeve 3 are threaded together, the steering screw 4 moves axially inside the steering gear housing 6. When the steering screw 4 moves axially to the maximum position, the limiting member 61 can press against the steering screw 4 to limit the axial movement of the steering screw 4. That is, when the steering screw 4 moves to the maximum position, the limiting member 61 can prevent it from continuing to move. Thus, the steering knuckle angle can be controlled by controlling the steering tie rod assembly 1, thereby controlling the wheel angle.

[0040] In some embodiments, the limiting member 61 is configured as a limiting post, which is inserted into the steering gear housing 6 radially along the steering screw 4, and at least a portion of the limiting post is located on the axial movement trajectory of the steering screw 4. That is, the limiting post can move radially along the steering screw 4, thereby pressing against the outer peripheral wall of the steering screw 4 to achieve axial limiting of the steering screw 4.

[0041] Specifically, such as Figure 2 and Figure 5 As shown, the limiting post is inserted into the steering gear housing 6 and is positioned on the axial movement trajectory of the steering screw 4. Thus, the limiting post can press against the steering screw 4 to axially limit the steering screw 4. When the steering screw 4 moves to its maximum position, such as when the steering screw 4 moves axially to the rightmost limit position, the limiting post can be inserted into the steering gear housing 6 radially along the steering screw 4, so that the end of the limiting post can press against the steering screw 4, thereby achieving axial limitation of the steering screw 4. When the steering screw 4 has not moved to the limit position, the limiting post can separate from the steering screw 4, so that the steering screw 4 can continue to move axially to control the wheel angle.

[0042] In some embodiments, the rear wheel steering gear 100 further includes a limiting seal 62, which is sleeved on the limiting post and has a sealing and pressing fit with the steering gear housing 6. That is, the limiting post can cooperate with the limiting seal 62 to realize the installation and fixation of the limiting post on the steering gear housing 6, thereby enabling the limiting post to achieve axial limiting of the steering screw 4.

[0043] Specifically, such as Figure 2 and Figure 5As shown, the limiting seal 62 is sleeved on the outside of the limiting post, and the limiting seal 62 is sealed and pressed against the steering gear housing 6. Thus, the limiting post is installed and fixed on the steering gear housing 6, and the steering gear housing 6 can axially limit the limiting post. In this way, when the limiting post presses against the steering screw 4, the steering screw 4 is limited. The sealing fit between the limiting seal 62 and the steering gear housing 6 can prevent the lubricant on the steering screw 4 from flowing out to the outside through the gap between the steering post and the steering gear housing 6, thereby ensuring the lubrication effect between the steering screw 4 and the steering sleeve 3.

[0044] The limiting seal 62 can be constructed as an O-ring, which can seal the limiting post to prevent lubricant leakage, maintain stable system pressure, and prevent external foreign objects, such as mud, sand, and water vapor, from entering the rear wheel steering gear 100, thereby reducing structural corrosion.

[0045] In some embodiments, the rear wheel steering system 100 further includes a detection element 7 and a steering controller. Both the detection element 7 and the steering motor 2 are electrically connected to the steering controller. The detection element 7 is located outside the steering lead screw 4 and is used to detect the axial position of the steering lead screw 4. The steering controller and the steering motor 2 are used to control the rotation angle of the steering motor 2 based on the detection result of the detection element 7. That is, the steering controller can control the axial displacement of the steering lead screw 4 by controlling the steering motor 2, and the steering controller can further control the steering motor 2 based on the detection data from the detection element 7, thereby achieving precise control of the axial displacement of the steering lead screw 4.

[0046] Specifically, the steering controller is located in the rear wheel steering gear 100, and the steering controller is electrically connected to the steering motor 2 and the detection element 7 respectively. Thus, the steering controller can control the detection element 7 and the steering motor 2 respectively. When it is necessary to control the steering of the wheels, the steering controller can control the steering motor 2 to start. The steering motor 2 can drive the steering sleeve 3 to rotate, and then achieve the axial displacement of the steering screw 4 through the threaded engagement between the steering sleeve 3 and the steering screw 4, so as to turn the wheels.

[0047] The detection element 7 is located on the outside of the steering screw 4. The detection element 7 can detect the axial displacement of the steering screw 4, and then transmit the detection information to the steering controller. The steering controller can determine whether to turn the steering motor 2 on or off based on the detection information, thereby further controlling the axial displacement of the steering screw 4.

[0048] Specifically, the steering controller can collect signals from the steering wheel angle sensor, vehicle speed sensor, yaw rate sensor, acceleration sensor, and wheel speed sensor in real time. It also receives vehicle status information from electronic control units such as ESP, EPS, and gateway via the CAN bus, including vehicle speed, estimated front wheel angle, actual front wheel angle, driving mode, and ESP activation status. The steering controller can filter, verify, and check the validity of the collected signals. Then, it can compare the calculated target rear wheel steering angle with the actual rear wheel steering angle fed back by the detection element 7. Based on the deviation between the two, it generates a precise PWM drive signal through a closed-loop control algorithm to control the steering motor 2. The motor can then drive the steering screw 4 to generate axial displacement through the reduction mechanism and motion conversion mechanism, namely the threaded engagement between the steering screw 4 and the steering sleeve 3, thereby achieving wheel steering.

[0049] Furthermore, the detection element 7 can be configured as a displacement sensor, which continuously monitors the linear displacement of the steering screw 4 and converts it into an actual rear wheel steering angle signal. This signal is then fed back to the steering controller so that the steering controller can correct the drive signal, ensuring that the actual steering angle accurately tracks the target steering angle, thereby achieving high-precision and stable control of the wheel angle.

[0050] In some embodiments, the steering tie rod assembly 1 includes an outer tie rod structure 11 and a lateral tie rod structure 12. One end of the lateral tie rod structure 12 forms a ball joint with the steering lead screw 4, and the other end of the lateral tie rod structure 12 is connected to one end of the outer tie rod structure 11. The other end of the outer tie rod structure 11 is used to connect to the steering knuckle. That is, the steering tie rod assembly 1 can be ball jointed with the steering lead screw 4, thereby avoiding motion interference between the axial movement of the steering lead screw 4 and the rotational movement of the steering knuckle.

[0051] Specifically, such as Figure 2 As shown, the left end of the tie rod structure 12 can be constructed as a ball head 121, and the right end of the steering screw 4 can be constructed as a ball joint 41. The ball head 121 and the ball joint 41 can form a ball joint, that is, the tie rod structure 12 can swing relative to the steering screw 4. The right end of the tie rod structure 12 is connected to the left end of the outer tie rod structure 11. When the steering screw 4 moves axially, it can drive the tie rod structure 12 to move synchronously. The tie rod structure 12 can further drive the outer tie rod structure 11 to move axially. The right end of the outer tie rod structure 11 is connected to the steering knuckle, so that the axial movement of the outer tie rod structure 11 can drive the steering knuckle to rotate.

[0052] In this process, the axial movement of the outer tie rod structure 11 and the rotation of the steering knuckle cause motion interference. At this time, the ball joint between the tie rod structure 12 and the steering screw 4 allows the outer tie rod structure 11 to swing slightly, thereby enabling the outer tie rod structure 11 to smoothly drive the steering knuckle to rotate.

[0053] Furthermore, the steering tie rod assembly 1 can change the Z-axis coordinate of the tie rod's outer hard point through a threaded adjustment mechanism, thereby adjusting the rear suspension toe angle gradient. For example, the lower end of the ball joint 41 can be designed as a screw, thus engaging with the blind hole thread of the tie rod structure 12.

[0054] In some embodiments, a first pulley is provided outside the motor shaft of the steering motor 2, and a second pulley 31 is provided outside the steering sleeve 3. The first pulley and the second pulley 31 are driven by a transmission belt 8. That is, the transmission between the steering motor 2 and the steering sleeve 3 can be achieved through the transmission between the first pulley, the second pulley 31 and the transmission belt 8, so that the steering motor 2 can drive the steering sleeve 3 to rotate.

[0055] Specifically, the first pulley is poweredly connected to the motor shaft of the steering motor 2, so that the steering motor 2 can transmit rotational power to the first pulley. The second pulley 31 is poweredly connected to the steering sleeve 3, so that the second pulley 31 can transmit steering power to the steering sleeve 3. Furthermore, the first pulley and the second pulley 31 are driven by the transmission belt 8, that is, the rotation of the first pulley can drive the rotation of the second pulley 31, thereby realizing the transmission of power.

[0056] During the rotation of the motor shaft of the steering motor 2, the motor shaft can drive the first pulley to rotate. The rotation of the first pulley can drive the transmission belt 8 to rotate. The rotating transmission belt 8 can further drive the second pulley 31 to rotate. Thus, the second pulley 31 can transmit rotational power to the steering sleeve 3, thereby driving the steering sleeve 3 to rotate, which can realize the axial movement of the steering screw 4.

[0057] This utility model also proposes a vehicle.

[0058] The vehicle according to the embodiments of the present invention includes a rear wheel steering system 100 of any of the above embodiments. The rear wheel steering system 100 can be configured as two units to control the two rear wheels of the vehicle independently, providing higher redundancy and safety. Furthermore, the oil sleeve structure lubricates the threaded connection between the steering screw 4 and the steering sleeve 3, thereby reducing wear and lowering maintenance costs. The rear wheel steering unit 100 can be configured as a ball screw actuator or an RWS module. The RWS module can collect the vehicle's dynamic data in real time and control the steering motor 2 to drive the steering tie rod assembly 1 to achieve active steering. When the vehicle is traveling at low speed, the rear wheels can deflect in the opposite direction to the front wheels to reduce the turning radius of the vehicle. When the vehicle is traveling at high speed, the rear wheels can deflect in the same direction as the front wheels to improve stability.

[0059] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0060] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A rear-wheel steering system, characterized in that, include: Steering tie rod assembly (1), said steering tie rod assembly (1) is used to connect to the steering knuckle; Steering motor (2), steering sleeve (3) and steering screw (4), the steering sleeve (3) is sleeved on the outside of the steering screw (4) and threaded with the steering screw (4), the steering screw (4) is connected to the steering tie rod assembly (1), the steering motor (2) is powered to drive the steering sleeve (3) to rotate, the steering sleeve (3) drives the steering screw (4) to move axially when rotating, and drives the steering knuckle to rotate through the steering tie rod assembly (1).

2. The rear wheel steering system according to claim 1, characterized in that, It also includes an oil sleeve structure for providing lubricant to the threaded connection between the steering sleeve (3) and the steering screw (4).

3. The rear wheel steering system according to claim 2, characterized in that, The steering screw (4) includes a first rod segment (42), a threaded segment (43), and a second rod segment (44) connected in sequence. The steering screw sleeve (3) is sleeved on the outside of the threaded segment (43) and threadedly engaged with the threaded segment (43). The oil sleeve structure includes a first oil sleeve (51) and / or a second oil sleeve. The first oil sleeve (51) is located at one end of the steering screw sleeve (3) near the first rod segment (42), and the second oil sleeve is located at one end of the steering screw sleeve (3) near the second rod segment (44).

4. The rear wheel steering system according to claim 1, characterized in that, It also includes a steering gear housing (6), the steering sleeve (3) is rotatably installed in the steering gear housing (6), and the steering screw (4) is axially movable in the steering gear housing (6); The steering gear housing (6) is provided with a limiting member (61), which is adapted to limit and press against the steering screw (4) when the steering screw (4) moves axially to the maximum position.

5. The rear wheel steering system according to claim 4, characterized in that, The limiting member (61) is constructed as a limiting post, which is inserted into the steering gear housing (6) radially along the steering screw (4), and at least a portion of the limiting post is located on the axial movement trajectory of the steering screw (4).

6. The rear wheel steering system according to claim 5, characterized in that, It also includes a limiting seal (62), which is sleeved on the outside of the limiting post and is in a sealing and pressing fit with the steering gear housing (6).

7. The rear wheel steering system according to claim 1, characterized in that, It also includes a detection element (7) and a steering controller. The detection element (7) and the steering motor (2) are both electrically connected to the steering controller. The detection element (7) is located outside the steering lead screw (4) and is used to detect the axial position of the steering lead screw (4). The steering controller and the steering motor (2) are used to control the rotation angle of the steering motor (2) according to the detection result of the detection element (7).

8. The rear wheel steering system according to claim 1, characterized in that, The steering tie rod assembly (1) includes an outer tie rod structure (11) and a lateral tie rod structure (12). One end of the lateral tie rod structure (12) is ball-jointed with the steering screw (4), and the other end of the lateral tie rod structure (12) is connected to one end of the outer tie rod structure (11). The other end of the outer tie rod structure (11) is used to connect to the steering knuckle.

9. The rear wheel steering system according to claim 1, characterized in that, The steering motor (2) has a first pulley on its motor shaft and a second pulley (31) on its steering sleeve (3). The first pulley and the second pulley (31) are driven by a transmission belt (8).

10. A vehicle, characterized in that, Includes the rear wheel steering system according to any one of claims 1-9.

Images