Single-wheel steering device and vehicle

Abstract

This application relates to a single-wheel steering system and a vehicle. The single-wheel steering system includes a housing, a roller screw assembly, and a drive unit. The housing has an inner cavity. The roller screw assembly is rotatably disposed within the inner cavity. At least a portion of the drive unit is disposed within the inner cavity, and the drive unit is drively connected to the roller screw assembly to drive the screw of the roller screw assembly to move. One end of the screw is configured to connect to a wheel. This application, through the above solution, achieves separate control of the left and right wheels while utilizing the rolling motion of the rollers to transmit power. This reduces the coefficient of friction during transmission, thereby reducing frictional losses and improving the transmission efficiency of the single-wheel steering system. Furthermore, the larger contact area between the rollers, the screw, and the nut increases the axial and radial loads that the single-wheel steering system can withstand, thus improving its load-bearing capacity. This enhances the reliability of the single-wheel steering system.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and more particularly to a single-wheel steering system and vehicle. Background Technology

[0002] To enhance vehicle maneuverability and handling, vehicles are equipped with wheel steering systems. A wheel steering system is a device that enables the wheels to turn. The vehicle's control unit receives information from various vehicle sensors, such as vehicle speed, steering wheel angle, and body roll angle. Based on this information, it outputs the appropriate steering angle and direction for the wheels under corresponding handling conditions. Then, through a drive unit (e.g., a drive motor or hydraulic system), it drives the steering system's transmission mechanism to move, thereby transmitting steering force to the wheels, causing them to turn at the required angle and direction.

[0003] In related technologies, in order to improve vehicle performance, the steering gear is set in two separate parts. That is, two separate steering gears are symmetrically arranged on the vehicle. The two separate steering gears are directly or indirectly connected to the left wheel and the right wheel on the same crossbeam or the same axle of the car, respectively, so as to control the rotation of the left wheel and the right wheel respectively, so that the left wheel and the right wheel can turn at the required angle and direction to achieve a variety of car operation effects.

[0004] However, this type of split steering system has lower transmission efficiency, poorer load-bearing capacity, and larger size. This results in lower reliability for split steering systems. Utility Model Content

[0005] This application provides a single-wheel steering system to improve the safety of single-wheel steering systems, thereby at least partially solving the above-mentioned technical problems.

[0006] To achieve the above objectives, according to a first aspect of this application, a single-wheel steering device is provided, comprising a housing, a roller screw assembly, and a drive device; the housing has an inner cavity; the roller screw assembly is rotatably disposed in the inner cavity, the roller screw assembly including a screw; at least a portion of the drive device is disposed in the inner cavity, the drive device being pulsatorically connected to the roller screw assembly to drive the screw to move; wherein one end of the screw is configured to be connected to a wheel.

[0007] Optionally, the ball screw assembly further includes a nut, a roller assembly, and a planetary carrier; the ball screw is disposed in the inner cavity; the nut is disposed in the inner cavity and sleeved on the ball screw; the roller assembly is ring-displaced between the nut and the ball screw, and the meshing teeth of the roller assembly mesh with the helical teeth of the ball screw and the meshing teeth of the nut respectively; the planetary carrier is rotatably disposed in the inner cavity and sleeved on the ball screw; wherein, the nut and the roller assembly are rotatably connected to the planetary carrier; the drive device is drively connected to the planetary carrier.

[0008] Optionally, the planetary carrier includes two planetary subcarriers, both of which are mounted on the lead screw and rotatably connected to the housing. The nut and roller assembly are located between the two planetary subcarriers, with the two ends of the nut rotatably connected to the two planetary subcarriers respectively, and the two ends of the roller assembly rotatably connected to the two planetary subcarriers respectively.

[0009] Optionally, the drive device is a belt drive device, with the driven pulley of the drive device sleeved on the nut, and the two ends of the driven pulley connected to two planetary carriers respectively.

[0010] Optionally, the passive pulley engages with the planetary carrier.

[0011] Optionally, a snap-fit ​​block is provided on the end face of the planetary subcarrier facing the driven pulley, and a snap-fit ​​hole is provided on the snap-fit ​​block. An elastic buckle is provided on the end face of the driven pulley, and the end of the elastic buckle away from the driven pulley passes through the snap-fit ​​hole and engages with the snap-fit ​​hole for blocking.

[0012] Optionally, the passive pulley is connected to the planetary carrier.

[0013] Optionally, a plurality of first slots are provided on the end face of the driven pulley, the plurality of first slots are arranged sequentially along the circumference of the lead screw, and a plurality of first blocks are provided on the end face of the planetary subcarrier facing the driven pulley, the plurality of first blocks being inserted into the plurality of first slots respectively.

[0014] Optionally, a first groove is provided on the inner circumferential surface of the nut; and / or, a second groove is provided on the outer circumferential surface of the nut.

[0015] Optionally, the roller assembly includes multiple rollers arranged sequentially along the circumference of the lead screw, with the meshing teeth in the middle of the rollers meshing with the helical teeth of the lead screw, and the meshing teeth at both ends of the rollers meshing with the meshing teeth of the nut.

[0016] Optionally, two planetary carriers are inserted into each end of each roller, and are clearance-fitted with the planetary carriers.

[0017] Optionally, a first axial bearing is provided between each planetary carrier and the housing along the axis of the lead screw.

[0018] Optionally, a gasket is provided between the housing and at least one first axial bearing along the axial direction of the lead screw.

[0019] Optionally, a second axial bearing is provided between each planetary carrier and the nut along the axial direction of the lead screw; and a radial bearing is provided between each planetary carrier and the housing along the radial direction of the lead screw.

[0020] Optionally, the single-wheel steering system also includes a steering knuckle fork connected to a lead screw and configured to connect to the wheel.

[0021] Optionally, the single-wheel steering system also includes a connecting rod disposed between the lead screw and the steering knuckle fork, the steering knuckle fork being connected to the lead screw via the connecting rod.

[0022] Optionally, the end of the connecting rod facing the lead screw is provided with a connecting threaded hole, and the end of the lead screw near the steering knuckle fork is inserted into the connecting threaded hole and threadedly connected to the connecting threaded hole.

[0023] Optionally, the lead screw has a smooth shaft section that is threadedly riveted to a connecting threaded hole.

[0024] Optionally, a limiting boss is provided on the outer peripheral surface of the connecting rod, and a limiting step is provided on the inner wall of the housing, with the limiting step located on the side of the limiting boss near the steering knuckle fork; wherein the outer diameter of the limiting boss is larger than the inner diameter of the limiting step.

[0025] Optionally, a first vibration damping pad is provided between the limiting boss and the limiting step, and the first vibration damping pad is connected to one of the limiting boss and the limiting step.

[0026] Optionally, the single-wheel steering system also includes an end bolt, the end of which passes through the steering knuckle fork and is threaded to the connecting rod.

[0027] Optionally, a countersunk plate is provided at the end of the steering knuckle fork facing the connecting rod, and the end of the connecting rod away from the lead screw is inserted into the countersunk plate.

[0028] Optionally, a first sealing ring is provided between the steering knuckle fork and the connecting rod, and the outer surface of the first sealing ring abuts against the steering knuckle fork and the connecting rod respectively.

[0029] Optionally, the single-wheel steering system also includes a telescopic tube, a connecting rod portion, and a steering knuckle fork located outside the housing. The middle portion of the telescopic tube is sleeved on the connecting rod, one end of the telescopic tube is sleeved on the end of the housing near the steering knuckle fork, and the other end of the telescopic tube is sleeved on the steering knuckle fork.

[0030] Optionally, the expansion joint is a corrugated pipe.

[0031] Optionally, the single-wheel steering system also includes a sliding bearing, which is disposed between the connecting rod and the housing, with the inner ring of the sliding bearing fitting against the connecting rod and the outer ring of the sliding bearing fitting against the housing.

[0032] Optionally, the outer circumferential surface of the connecting rod is provided with an annular groove, which extends circumferentially along the connecting rod, and the inner ring of the sliding bearing is located in the annular groove.

[0033] Alternatively, the sliding bearing is an open bearing.

[0034] Optionally, the single-wheel steering system also includes an anti-rotation bearing, which is disposed between the connecting rod and the housing. At least a portion of the inner surface of the anti-rotation bearing is in stop engagement with the connecting rod along the circumferential direction of the lead screw, and at least a portion of the outer circumferential surface of the anti-rotation bearing is in stop engagement with the housing along the circumferential direction of the lead screw.

[0035] Optionally, the outer surface of the connecting rod is provided with a first plane, the outer shell is provided with a second plane, and the inner and outer surfaces of the anti-rotation bearing are respectively provided with an inner plane and an outer plane, the inner plane being in contact with the first plane and the outer plane being in contact with the second plane.

[0036] Optionally, a second damping pad is provided between the housing and the steering knuckle fork, and the second damping pad is connected to one of the steering knuckle fork and the housing.

[0037] Optionally, the single-wheel steering gear also includes a position sensor, which includes a synchronizing element and an identification component. The synchronizing element is disposed in the inner cavity and moves synchronously with the lead screw. The identification component is disposed on the outer shell and is connected to the controller signal of the drive device. The identification component collects the position information of the synchronizing element and sends the position information to the controller. The controller controls the working state of the drive device according to the position information.

[0038] Optionally, the synchronizing element is magnetic, and the identification component determines the position information of the synchronizing element based on changes in the magnetic field.

[0039] Optionally, the drive device includes a motor and a transmission mechanism. The transmission mechanism is located in the inner cavity, the motor is located outside the housing, the output shaft of the motor passes through the housing, and the output shaft is connected to the ball screw assembly through the transmission mechanism.

[0040] Optionally, the transmission mechanism includes a driving pulley, a driven pulley, and a timing belt. The driving pulley is sleeved on the output shaft, the driven pulley is connected to the ball screw assembly, and the two ends of the timing belt are sleeved on the driving pulley and the driven pulley, respectively.

[0041] Optionally, the single-wheel steering gear also includes a connecting bolt, and has a mounting through hole and an arc-shaped hole on the housing, the arc-shaped hole extending around the axis of the mounting through hole; a positioning boss is provided on the motor housing, the axis of the positioning boss is offset relative to the output shaft of the motor, the positioning boss is inserted into the mounting through hole, and the end of the shank of the connecting bolt passes through the arc-shaped hole and is threadedly connected to the motor housing.

[0042] Optionally, the housing includes a first housing member and a second housing member, which are connected to define an inner cavity.

[0043] According to a second aspect of this application, a vehicle is provided that includes at least two of the aforementioned single-wheel steering systems.

[0044] In the single-wheel steering system of this application embodiment, by using a roller screw assembly as the transmission structure, power can be transmitted by the rolling motion of the rollers while achieving separate control of the left and right wheels. This reduces the coefficient of friction during transmission, thereby reducing frictional losses and improving the transmission efficiency of the single-wheel steering system. Furthermore, the larger contact area between the rollers, the screw, and the nut increases the axial and radial loads that the single-wheel steering system can withstand, thus enhancing its load-bearing capacity. This improves the reliability of the single-wheel steering system.

[0045] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0048] Figure 1 This is a schematic diagram of the structure of a single-wheel steering system provided in an exemplary embodiment of this disclosure;

[0049] Figure 2 This is a side view of a single-wheel steering system provided in an exemplary embodiment of this disclosure;

[0050] Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure of AA;

[0051] Figure 4 yes Figure 2 A cross-sectional view of the middle BB rotated 90° clockwise;

[0052] Figure 5 This is a schematic diagram of a single-wheel steering system provided in an exemplary embodiment of this disclosure applied to a vehicle;

[0053] Figure 6 This is a rendering of the vehicle steering provided in an exemplary embodiment of this disclosure;

[0054] Figure 7 This is a schematic diagram of the longitudinal section structure of the roller screw assembly provided in an exemplary embodiment of this disclosure;

[0055] Figure 8 This is a schematic diagram of the structure of the passive pulley and roller screw assembly provided in an exemplary embodiment of this disclosure;

[0056] Figure 9 This is a schematic diagram of the structure of the planetary subcarrier provided in an exemplary embodiment of this disclosure;

[0057] Figure 10 This is a schematic diagram of the passive pulley provided in an exemplary embodiment of this disclosure;

[0058] Figure 11 This is a schematic diagram of the structure of the roller provided in an exemplary embodiment of this disclosure;

[0059] Figure 12 yes Figure 3 A magnified structural diagram of section C;

[0060] Figure 13 yes Figure 3 A magnified structural diagram of section D;

[0061] Figure 14 This is a schematic diagram of the lead screw structure provided in an exemplary embodiment of this disclosure;

[0062] Figure 15 yes Figure 4 A magnified structural diagram of section E in the middle;

[0063] Figure 16 This is a schematic diagram of the structure of the sliding bearing provided in an exemplary embodiment of this disclosure;

[0064] Figure 17 This is a schematic diagram of the structure of the connecting rod provided in an exemplary embodiment of this disclosure;

[0065] Figure 18 This is a schematic diagram of the anti-rotation bearing provided in an exemplary embodiment of this disclosure;

[0066] Figure 19 This is a partial structural schematic diagram of the outer casing provided in an exemplary embodiment of this disclosure;

[0067] Figure 20 yes Figure 4 A magnified structural diagram of section F in the middle;

[0068] Figure 21 This is a schematic diagram of synchronous belt adjustment provided in an exemplary embodiment of this disclosure;

[0069] Figure 22 This is an exploded view of the casing provided in an exemplary embodiment of this disclosure.

[0070] Explanation of reference numerals in the attached figures:

[0071] 100-Single wheel steering gear;

[0072] 10-Outer shell; 11-First shell component; 12-Second shell component; 13-Inner cavity; 14-Limiting step; 15-Second plane; 16-Mounting through hole; 17-Arc-shaped hole; 18-Locking pin hole; 19-Locking pin shaft;

[0073] 20 - Roller screw assembly; 21 - Screw; 211 - Shaft section; 212 - Threaded section; 213 - Tooth groove;

[0074] 22-Nut; 221-First groove; 222-Second groove;

[0075] 23-Roller assembly; 231-Roller; 2311-First meshing tooth; 2312-Second meshing tooth;

[0076] 24-Planet carrier; 241-Planet subcarrier; 2411-Snap-fit ​​block; 2412-Matching post; 2413-Snap-fit ​​hole; 2414-First snap-fit ​​block; 2415-Mounting groove; 2416-Shaft; 2417-Disc;

[0077] 30-Drive device; 31-Transmission mechanism; 311-Driven pulley; 3111-Elastic buckle; 3112-Wedge block; 3113-Relief groove; 3114-First slot;

[0078] 312 - Drive pulley; 313 - Synchronous belt; 314 - Meshing teeth;

[0079] 32-Motor; 321-Positioning boss; 322-Output shaft;

[0080] 41-First axial bearing; 42-Second axial bearing; 43-Radial bearing; 44-Sliding bearing; 45-Anti-rotation bearing; 451-Inner plane; 452-Outer plane;

[0081] 46 - Gasket; 471 - First damping pad; 472 - Second damping pad; 48 - End bolt; 491 - First sealing ring; 492 - Second sealing ring;

[0082] 50 - Sensor harness;

[0083] 51-Steering knuckle fork; 511-Recessed platform;

[0084] 52-Connecting rod; 521-Connecting threaded hole; 522-Limiting boss; 523-First plane; 524-Square groove; 525-Annular groove;

[0085] 53-Telescopic tube; 54-Synchronizing component; 55-Identification component; 56-Connecting bolt;

[0086] 601 - Left wheel; 602 - Right wheel. Detailed Implementation

[0087] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0088] The following combination Figures 1 to 22 The present application provides a detailed description of a steering system and a vehicle according to its embodiments.

[0089] Please see Figures 1 to 4 , Figure 1 This is a schematic diagram of the structure of the single-wheel steering system 100 provided in an exemplary embodiment of this disclosure. Figure 2 This is a side view of a single-wheel steering system 100 provided in an exemplary embodiment of this disclosure. Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure of AA. Figure 4 yes Figure 2 A cross-sectional view of BB rotated 90° clockwise is shown in the diagram. In a first aspect, embodiments of this application provide a single-wheel steering system 100. The single-wheel steering system 100 includes a housing 10, a roller screw assembly 20, and a drive unit 30. The housing 10 has an inner cavity 13. The roller screw assembly 20 is rotatably disposed in the inner cavity 13, and the roller screw assembly 20 includes a lead screw 21. At least a portion of the drive unit 30 is disposed in the inner cavity 13. The drive unit 30 is drively connected to the roller screw assembly 20 to drive the lead screw 21 to move. One end of the lead screw 21 is configured to connect to a wheel.

[0090] It can be understood that the drive device 30 is a combination of the motor 32 and the transmission mechanism 31. The transmission mechanism 31 can be a gear set, a pulley mechanism, or a sprocket mechanism, etc. The drive device 30 can be entirely disposed in the inner cavity 13, or part of it can be disposed in the inner cavity 13 and the other part can be disposed outside the outer shell 10.

[0091] It can be understood that the roller screw assembly 20 includes a screw 21, a nut 22 sleeved on the screw 21, a roller group 23 arranged around the nut 22 and the screw 21, and a planetary carrier 24 that rotatably supports the nut 22 and the roller group 23. The roller group 23 includes a plurality of rollers 231 arranged on the same circumference, the center of which is located on the axis of the screw 21.

[0092] For example, the roller screw assembly 20 is rotatably disposed in the inner cavity 13 via a rotary bearing.

[0093] It is understandable that the lead screw 21 can be directly connected to the wheel, or it can be connected to the wheel through the adjusting arm.

[0094] For example, the end face of the lead screw 21 away from the wheel is provided with a toothed groove 213 that engages with a wrench. The cross-section of the toothed groove 213 is polygonal, for example, a regular hexagon. In this way, the lead screw 21 can be rotated by engaging the wrench with the toothed groove 213, thereby improving the assembly efficiency of the single-wheel steering gear 100.

[0095] When adjusting the angle of wheel deflection relative to the vehicle's centerline, the drive unit 30 operates to drive the roller screw assembly 20 to rotate, thereby causing the screw 21 to move left or right along the vehicle's lateral axis (corresponding to...). Figure 3 The lead screw 21 moves up or down to pull or push the wheel, causing the wheel to rotate around a direction perpendicular to the horizontal plane, thereby turning the wheel at the required angle and direction.

[0096] For example, two steering gears can be symmetrically arranged at the rear of the vehicle. These two steering gears are indirectly or directly connected to the left wheel 601 and the right wheel 602, respectively, so that the rotation of the left wheel 601 and the right wheel 602 can be controlled separately through the two steering gears. Figure 5 As shown, Figure 5 This is a schematic diagram of a single-wheel steering system 100 provided in an exemplary embodiment of this disclosure applied to a vehicle. By adjusting the rotation angle and direction of the left wheel 601 and right wheel 602, various steering control effects can be achieved to adapt to various driving situations. For example, by controlling the two wheels to turn in the same direction and at the same angle respectively, a first steering control effect can be achieved, such as... Figure 6 As shown in Figure (a), both wheels rotate parallel to each other at a certain angle. This steering control effect can be applied to lane changes to improve vehicle stability. For example, a second steering control effect can be achieved by controlling the wheels on both sides to turn in the same direction but at different angles, such as... Figure 6 As shown in Figure (b), the left wheel has a larger steering angle, while the right wheel has a smaller steering angle. This indicates that the left wheel can perform separate actions according to the Ackermann principle to achieve... Figure 6 The steering control effect is shown in Figure (b). The second steering control effect can be used for low-speed steering, U-turns, and other situations, reducing the vehicle's turning radius. Furthermore, a third steering control effect can be achieved by separately controlling the direction and angle of rotation of the wheels on both sides, such as... Figure 6 As shown in Figures (c) and (d), Figure (c) makes the wheels "outward-pointing," while Figure (d) makes the wheels "inward-pointing." This third control effect can be used in emergency braking to increase vehicle drag, thereby reducing braking distance and improving vehicle safety.

[0097] According to Ackermann's principle, when a vehicle turns, the inner and outer wheels need to travel different distances. The inner wheel travels a shorter path, while the outer wheel travels a longer path. To ensure a smooth turn and that each wheel maintains pure rolling without lateral slippage, the steering angle of the inner wheel needs to be greater than that of the outer wheel.

[0098] In this embodiment, by using the roller screw assembly 20 as the transmission structure of the single-wheel steering gear 100, power can be transmitted by the rolling motion of the rollers 231 while achieving separate control of the left and right wheels. This reduces the coefficient of friction during transmission, thereby reducing frictional losses and improving the transmission efficiency of the single-wheel steering gear 100. Furthermore, the larger contact area between the rollers 231, the screw 21, and the nut 22 increases the axial and radial loads that the single-wheel steering gear 100 can withstand, thus enhancing its load-bearing capacity. This improves the reliability of the single-wheel steering gear 100.

[0099] In addition, the roller screw assembly 20 has a compact structure, and when combined with the single-wheel steering gear 100, it can reduce the size of the single-wheel steering gear 100. This allows the single-wheel steering gear 100 to achieve a variety of steering control effects in a smaller space, and provides sufficient installation space for subsequent iterative upgrades of the single-wheel steering gear 100 and its surrounding components.

[0100] Please see Figure 7 , Figure 7 This is a longitudinal cross-sectional view of the roller screw assembly 20 provided in an exemplary embodiment of this disclosure. In some embodiments, the roller screw assembly 20 further includes a nut 22, a roller assembly 23, and a planetary carrier 24. The screw 21 is disposed in the inner cavity 13. The nut 22 is disposed in the inner cavity 13 and sleeved on the screw 21. The roller assembly 23 is ring-distributed between the nut 22 and the screw 21. The meshing teeth of the roller assembly 23 mesh with the helical teeth of the screw 21 and the meshing teeth of the nut 22, respectively. The planetary carrier 24 is rotatably disposed in the inner cavity 13 and sleeved on the screw 21. Both the nut 22 and the roller assembly 23 are rotatably connected to the planetary carrier 24. The drive device 30 is drively connected to the planetary carrier 24.

[0101] It is understandable that the meshing teeth at different parts of the roller 231 mesh with the meshing teeth of the nut 22 and the helical teeth of the lead screw 21, respectively.

[0102] It is understood that the nut 22 and the lead screw 21 are coaxially arranged, and the roller assembly 23 includes multiple rollers 231 arranged on the same circumference.

[0103] For example, the meshing teeth in the middle of the roller 231 may mesh with the helical teeth of the lead screw 21, and the meshing teeth at both ends of the roller 231 may mesh with the meshing teeth of the nut 22. Alternatively, the meshing teeth in the middle of the roller 231 may mesh with the meshing teeth of the nut 22, and the meshing teeth at both ends of the roller 231 may mesh with the helical teeth of the lead screw 21.

[0104] In this system, the drive unit 30 drives the planetary carrier 24 to rotate. The planetary carrier 24 rotates around the lead screw 21, which in turn drives the roller 231 to rotate around the lead screw 21. The roller 231 also rotates on its own axis, and the friction between the roller 231 and the nut 22 causes the nut 22 to rotate. The roller 231 has no helix angle, while the lead screw 21 has a helix angle, thus the rotation of the roller 231 pushes the lead screw 21 to move along its own axis. In this way, the rotational motion from the drive unit 30 is converted into linear motion of the lead screw 21, causing the lead screw 21 to move left or right to pull or push the wheel, thereby causing the wheel to rotate in a direction perpendicular to the horizontal plane, and thus steering the wheel according to the desired angle and direction.

[0105] It is understandable that the reaction force of the roller 231 pushing the lead screw 21 to move is transmitted to the nut 22, the nut 22 is transmitted to the planetary carrier 24, and finally transmitted to the outer casing 10 through the planetary carrier 24.

[0106] Please see Figure 7 In some embodiments, the planetary carrier 24 includes two planetary subcarriers 241. Both planetary subcarriers 241 are mounted on the lead screw 21 and are rotatably connected to the housing 10. The nut 22 and the roller assembly 23 are located between the two planetary subcarriers 241. Both ends of the nut 22 are rotatably connected to the two planetary subcarriers 241, respectively. Both ends of the roller assembly 23 are rotatably connected to the two planetary subcarriers 241, respectively. This design simplifies the structure of the planetary carrier 24 and improves the ease of assembly of the planetary carrier 24, the roller assembly 23, and the nut 22.

[0107] For example, the two ends of the nut 22 are rotatably connected to the two planetary carriers 241 respectively through rotating bearings, and the two ends of the roller assembly 23 are inserted into the planetary carriers 241 and are clearance-fitted with the planetary carriers 241 to realize the rotatable connection between the roller assembly 23 and the planetary carriers 241.

[0108] Please see Figure 3 and Figure 8 , Figure 8This is a schematic diagram of the structure of the passive pulley 311 and the ball screw assembly 20 provided in an exemplary embodiment of this disclosure. In some embodiments, the drive device 30 is a belt drive device. The passive pulley 311 of the drive device 30 is sleeved on the nut 22. Both ends of the passive pulley 311 are respectively connected to two planetary carriers 241. In this way, the ball screw assembly 20 can be assembled into one piece through the passive pulley 311, thereby reducing the difficulty of product transportation and assembly.

[0109] In some embodiments, the passive pulley 311 engages with the planetary carrier 241. This improves the ease and efficiency of assembling the passive pulley 311 with the planetary carrier 241.

[0110] It is understandable that, in addition to snapping the passive pulley 311 to the planetary carrier 241 to achieve the connection between the passive pulley 311 and the planetary carrier, the passive pulley 311 can also be glued, bolted, or riveted to the planetary carrier 241.

[0111] Please see Figure 9 and Figure 10 , Figure 9 This is a schematic diagram of the structure of the planetary subcarrier 241 provided in an exemplary embodiment of this disclosure. Figure 10 This is a schematic diagram of the passive pulley 311 provided in an exemplary embodiment of this disclosure. In some embodiments, a locking block 2411 is provided on the end face of the planetary carrier 241 facing the passive pulley 311. A locking hole 2413 is provided on the locking block 2411. An elastic buckle 3111 is provided on the end face of the passive pulley 311. The end of the elastic buckle 3111 away from the passive pulley 311 passes through the locking hole 2413 and engages with it. This makes the locking structure between the passive pulley 311 and the planetary carrier 241 simple and easy to operate.

[0112] Specifically, a clearance groove 3113 is provided on the end face of the driven pulley 311, and an elastic buckle 3111 is disposed in the clearance groove 3113. The elastic buckle 3111 has a U-shaped structure, with its two ends facing the adjacent planetary carrier 241. Wedge blocks 3112 are provided on both sides of the elastic buckle 3111. When the driven pulley 311 is engaged with the planetary carrier 241, the end of the elastic buckle 3111 is inserted into the buckle hole 2413. Under the guidance of the wedge-shaped surface of the wedge block 3112, the two ends of the elastic buckle 3111 move closer to each other until the wedge block 3112 passes through the buckle hole 2413, the elastic arm returns to its original state, and the wedge block 3112 and the planetary carrier 241 are engaged in a stop-fitting cooperation.

[0113] Specifically, multiple snap-fit ​​blocks 2411 are provided on the inner circumferential surface of the planetary carrier 241. Each snap-fit ​​block 2411 includes two mating posts 2412. One end of the mating post 2412 is connected to the planetary carrier 241. A snap-fit ​​hole 2413 is defined between the two mating posts 2412 in each set of mating posts 2412. When the driven pulley 311 is snapped into the planetary carrier 241, the end of the elastic buckle 3111 is inserted between the two mating posts 2412. Guided by the wedge-shaped surface of the wedge block 3112, the two ends of the elastic buckle 3111 move closer to each other until the wedge block 3112 passes through the snap-fit ​​hole 2413. The elastic arm returns to its original state, and the wedge block 3112 and the mating post 2412 stop the engagement.

[0114] For example, there are multiple elastic buckles 3111 and multiple locking holes 2413. The multiple elastic buckles 3111 are evenly distributed around the axis of the lead screw 21, and each of the multiple elastic buckles 3111 corresponds to a multiple locking hole 2413. Each elastic buckle 3111 engages with the corresponding locking hole 2413.

[0115] In some embodiments, the passive pulley 311 is inserted into the planetary carrier 241. This increases the mating surface between the passive pulley 311 and the planetary carrier 241, thereby improving the stability of the passive pulley 311 in transmitting torque to the planetary carrier 241.

[0116] Regarding the specific insertion between the passive pulley 311 and the planetary carrier 241, the following scheme can be adopted. In some embodiments, a plurality of first slots 3114 are provided on the end face of the passive pulley 311. The plurality of first slots 3114 are arranged sequentially along the circumference of the lead screw 21. A plurality of first blocks 2414 are provided on the end face of the planetary carrier 241 facing the passive pulley 311. The plurality of first blocks 2414 are respectively inserted into the plurality of first slots 3114. In this way, the insertion structure between the passive pulley 311 and the planetary carrier 241 is simple, which is conducive to the assembly of the passive pulley 311 and the planetary carrier 241.

[0117] For example, there are multiple first slots 3114 and multiple first blocks 2414. The multiple first slots 3114 are evenly distributed around the axis of the lead screw 21, and each of the multiple first slots 3114 corresponds to a multiple of the multiple first blocks 2414. Each first slot 3114 cooperates with the corresponding first block 2414.

[0118] Please see Figure 7In some embodiments, a first groove 221 is provided on the inner circumferential surface of the nut 22. The first groove 221 can both avoid the meshing teeth on the roller 231 that mesh with the lead screw 21, so that the meshing teeth of the roller 231 and the lead screw 21 have a larger radius to improve transmission reliability, and store grease in the first groove 221 to lubricate the contact surfaces between components with relative movement, thereby reducing friction and improving transmission efficiency.

[0119] Please see Figure 7 In some embodiments, a second groove 222 is provided on the outer peripheral surface of the nut 22. The first groove 221 can reduce the weight of the nut 22, which is beneficial to the lightweight design of the single-wheel steering gear 100, and can also store grease in the second groove 222 to lubricate the contact surfaces between components with relative movement, thereby reducing friction and improving transmission efficiency.

[0120] Please see Figure 7 In some embodiments, the roller assembly 23 includes a plurality of rollers 231 arranged sequentially along the circumference of the lead screw 21. The meshing teeth in the middle of the rollers 231 mesh with the helical teeth of the lead screw 21. The meshing teeth at both ends of the rollers 231 mesh with the meshing teeth of the nut 22.

[0121] For example, the roller assembly 23 includes 12 rollers 231, which are symmetrically distributed along the axis of the lead screw 21.

[0122] Specifically, the meshing teeth of roller 231 meshing with nut 22 are first meshing teeth 2311, and the meshing teeth of roller 231 meshing with lead screw 21 are second meshing teeth 2312. The tip circle diameter of the first meshing tooth 2311 is smaller than the tip circle diameter of the second meshing tooth 2312. Figure 11 As shown, Figure 11 This is a schematic diagram of the structure of the roller 231 provided in an exemplary embodiment of this disclosure.

[0123] Please see Figure 7 and Figure 9 In some embodiments, two planetary carriers 241 are inserted into each end of each roller 231, and are clearance-fitted with the planetary carriers 241. This simplifies the fit between the rollers 231 and the planetary carriers 24, improving assembly efficiency.

[0124] Specifically, multiple mounting grooves 2415 are provided on the surface of the planetary carrier 241 facing the roller assembly 23, such as... Figure 9 As shown. Each planetary carrier 241 has multiple mounting grooves 2415 that correspond one-to-one with multiple rollers 231 of the roller assembly 23, and the ends of the rollers 231 fit into the corresponding mounting grooves 2415.

[0125] Please see Figure 3 and Figure 4 In some embodiments, a first axial bearing 41 is provided between each planetary carrier 241 and the housing 10 along the axial direction of the lead screw 21. In this way, while the planetary carrier 24 bears the axial load, the friction between the planetary carrier 24 and the housing 10 can be reduced, thereby improving the smoothness of the rotation of the planetary carrier 24 relative to the housing 10.

[0126] Please see Figure 3 , Figure 4 as well as Figure 12 , Figure 12 yes Figure 3 An enlarged structural schematic diagram of part C. In some embodiments, a shim 46 is provided between the housing 10 and at least one first axial bearing 41 along the axial direction of the lead screw 21. Thus, during assembly, shims 46 of different thicknesses can be optionally installed, thereby adjusting the preload of the steering gear in the axial direction of the lead screw 21. Specifically, the housing 10 includes a first housing member 11 and a second housing member 12 interconnected to define an inner cavity 13. A first axial bearing 41, a planetary carrier 241, and a nut 22, i.e., a roller assembly 23, are all located within the first housing member 11. A portion of another planetary carrier 241 is located within the first housing member 11, and another portion is located within the second housing member 12. During assembly, the distance between the bearing located within the first housing member 11 and the surface of the first housing member 11 facing the second housing member 12 is measured. Figure 4 The X value is used to select shims 46 of different thicknesses based on the magnitude of the X value and the required preload. The thicker the shim 46, the greater the preload. After selecting the shim 46 of the required thickness, the first housing 11 and the second housing 12 are locked together with bolts, so that the steering gear can reach the set preload, which helps to improve the system rigidity.

[0127] Please see Figure 7 In some embodiments, a second axial bearing 42 is provided between each planetary carrier 241 and the nut 22 along the axial direction of the lead screw 21. In this way, while the nut 22 bears the axial load, the friction between the nut 22 and the planetary carrier 24 can be reduced, thereby improving the smoothness of the rotation of the nut 22 relative to the planetary carrier 24.

[0128] Please see Figure 3 and Figure 4 In some embodiments, a radial bearing 43 is provided between each planetary carrier 241 and the housing 10 along the radial direction of the lead screw 21. In this way, while bearing the radial load, the friction between the planetary carrier 24 and the housing 10 can be reduced, thereby improving the smoothness of the rotation of the planetary carrier 24 relative to the housing 10.

[0129] Specifically, such as Figure 9As shown, each planetary carrier 241 includes a shaft portion 2416 and a disk portion 2417 connected to each other. A first axial bearing 41 is disposed between the end face of the disk portion 2417 away from the nut 22 and the housing 10, and a radial bearing 43 is disposed between the outer peripheral surface of the shaft portion 2416 and the housing 10. Figure 12 As shown.

[0130] Please see Figures 1 to 4 In some embodiments, the single-wheel steering system 100 further includes a steering knuckle fork 51. The steering knuckle fork 51 is connected to the lead screw 21. The steering knuckle fork 51 is configured to connect to the wheel. This improves the ease of operation and reliability of connecting the single-wheel steering system 100 to the wheel, enabling the single-wheel steering system 100 to smoothly drive the wheel to rotate.

[0131] It is understandable that the lead screw 21 is connected to the wheel via the steering knuckle fork 51.

[0132] It is understandable that the steering knuckle fork 51 can be directly connected to the lead screw 21 or indirectly connected to the lead screw 21.

[0133] Please see Figure 3 and Figure 4 In some embodiments, the single-wheel steering gear 100 further includes a connecting rod 52. The connecting rod 52 is disposed between the lead screw 21 and the steering knuckle fork 51. The steering knuckle fork 51 is connected to the lead screw 21 via the connecting rod 52.

[0134] It is understandable that directly connecting the lead screw 21 to the steering knuckle fork 51 would result in a larger length of the lead screw 21, requiring higher machining precision and thus higher machining costs. Therefore, using a connecting rod 52 to connect the steering knuckle fork 51 and the lead screw 21 allows both the connecting rod 52 and the lead screw 21 to have high dimensional accuracy while reducing machining costs, thereby improving the economy of the single-wheel steering system 100.

[0135] Please see Figure 13 , Figure 13 yes Figure 3 An enlarged structural diagram of part D is shown. In some embodiments, the end of the connecting rod 52 facing the lead screw 21 is provided with a connecting threaded hole 521. The end of the lead screw 21 near the steering knuckle fork 51 is inserted into the connecting threaded hole 521 and threadedly connected to the connecting threaded hole 521. This improves the ease of operation of the connection between the lead screw 21 and the connecting rod 52, thereby improving the assembly efficiency of the single-wheel steering gear 100.

[0136] Please see Figure 13 and Figure 14 , Figure 14 This is a schematic diagram of the structure of the lead screw 21 provided in an exemplary embodiment of this disclosure. In some embodiments, the lead screw 21 has an optical axis segment 211, which is threadedly riveted to the threaded hole 521.

[0137] It is understandable that the lead screw 21 also has a threaded section 212, which is located at the end of the optical shaft section 211 near the steering knuckle fork 51.

[0138] It can be understood that the outer diameter of the optical axis segment 211 is larger than the minor diameter of the connecting threaded hole 521 (i.e., the diameter of the imaginary cylindrical surface coinciding with the crest of the internal thread of the connecting threaded hole 521), and smaller than the major diameter of the connecting threaded hole 521 (i.e., the diameter of the imaginary cylindrical surface coinciding with the root of the internal thread of the connecting threaded hole 521). The threaded segment 212 of the lead screw 21 is threadedly connected to the connecting threaded hole 521, and the optical axis segment 211 is screwed into the connecting threaded hole 521. The optical axis segment 211 damages the thread of the connecting threaded hole 521, thereby preventing the threaded segment 212 of the lead screw 21 from exiting the connecting threaded hole 521, achieving the purpose of preventing loosening. In this way, the reliability of the connection between the lead screw 21 and the connecting rod 52 can be improved.

[0139] Please see Figure 13 and 14 In some embodiments, a limiting boss 522 is provided on the outer peripheral surface of the connecting rod 52. A limiting step 14 is provided on the inner wall of the housing 10. The limiting step 14 is located on the side of the limiting boss 522 near the steering knuckle fork 51; wherein the outer diameter of the limiting boss 522 is larger than the inner diameter of the limiting step 14. Thus, the lead screw 21 can move in the first direction (i.e., the lead screw 21 along...). Figure 3 When the screw 21 moves downwards (as shown), the limiting boss 522 abuts against the limiting step 14 to limit the travel of the screw 21 in the first direction, thereby preventing the screw 21 from disengaging from the roller assembly 23 when it runs in the first direction. This improves the reliability of the single-wheel steering system 100.

[0140] Please see Figure 14 In some embodiments, a first damping pad 471 is provided between the limiting boss 522 and the limiting step 14. The first damping pad 471 is connected to one of the limiting boss 522 and the limiting step 14. In this way, the contact between the limiting boss 522 and the limiting step 14 can be buffered to reduce the impact noise generated when they contact.

[0141] Specifically, the first damping pad 471 is annular, which is sleeved on the connecting rod 52 and fixed on the limiting step 14.

[0142] Please see Figure 15 , Figure 15 yes Figure 4An enlarged structural diagram of part E is shown. In some embodiments, the single-wheel steering gear 100 further includes an end bolt 48. The end of the shank of the end bolt 48 passes through the steering knuckle fork 51 and is threaded to the connecting rod 52. Thus, the steering knuckle fork 51 and the connecting rod 52 can be detachably connected by the end bolt 48, thereby improving the ease of assembly of the single-wheel steering gear 100 and thus improving the manufacturing efficiency of the single-wheel steering gear 100.

[0143] Please see Figure 15 In some embodiments, a countersunk plate 511 is provided at the end of the steering knuckle fork 51 facing the connecting rod 52, and the end of the connecting rod 52 away from the lead screw 21 is inserted into the countersunk plate 511. In this way, the position of the connecting rod 52 relative to the steering knuckle fork 51 can be quickly positioned by the countersunk plate 511, thereby improving the speed of connection between the steering knuckle fork 51 and the steering rod, which is conducive to improving the manufacturing efficiency of the single-wheel steering gear 100.

[0144] Please see Figure 15 In some embodiments, a first sealing ring 491 is provided between the steering knuckle fork 51 and the connecting rod 52. The outer surface of the first sealing ring 491 abuts against both the steering knuckle fork 51 and the connecting rod 52. Thus, the first sealing ring 491 can seal the contact surfaces between the steering knuckle fork 51 and the connecting rod 52, and the compression of the first sealing ring 491 can apply a preload to the end bolt 48, thereby improving the reliability of the connection between the steering knuckle fork 51 and the connecting rod 52 and enhancing the load-bearing capacity of the single-wheel steering gear 100.

[0145] Specifically, a chamfer is provided around the end face of the connecting rod 52 that is inserted into the recessed platform 511, and the first sealing ring 491 is located at the chamfer.

[0146] Please see Figure 3 , Figure 4 and Figure 15 In some embodiments, the single-wheel steering system 100 further includes a telescopic tube 53. A portion of the connecting rod 52 and the steering knuckle fork 51 are located outside the housing 10. The middle portion of the telescopic tube 53 is sleeved on the connecting rod 52. One end of the telescopic tube 53 is sleeved on the end of the housing 10 near the steering knuckle fork 51. The other end of the telescopic tube 53 is sleeved on the steering knuckle fork 51.

[0147] It is understood that the drive unit 30 drives the roller screw assembly 20 to drive the screw 21 to move along its own axis, thereby causing the steering knuckle fork 51 to move closer to or away from the housing 10. Based on this, the telescopic tube 53 can protect the connecting rod 52 exposed outside the housing 10 to prevent dust and other impurities from entering the housing 10, thereby improving the reliability and service life of the single-wheel steering gear 100.

[0148] Please see Figure 15In some embodiments, the telescopic tube 53 is a corrugated tube. The corrugated tube can bend and expand freely within a certain range, allowing it to adapt to different installation environments and spatial layouts, thereby reducing installation difficulty and cost.

[0149] Please see Figure 3 and Figure 13 In some embodiments, the single-wheel steering gear 100 further includes a sliding bearing 44. The sliding bearing 44 is annularly disposed between the connecting rod 52 and the housing 10. The inner ring of the sliding bearing 44 is in contact with the connecting rod 52. The outer ring of the sliding bearing 44 is in contact with the housing 10.

[0150] The sliding bearing 44 is sleeved around the connecting rod 52 and moves synchronously with it. The outer circumferential surface of the sliding bearing 44 contacts the housing 10, thereby providing radial support for the connecting rod 52 to support the end of the lead screw 21 away from the roller 231. This improves the stability of the single-wheel steering gear 100 transmission.

[0151] In addition, the sliding bearing 44 can reduce the coefficient of friction between the connecting rod 52 and the housing, thus preventing abnormal noise.

[0152] Please see Figure 13 In some embodiments, the outer circumferential surface of the connecting rod 52 is provided with an annular groove 525, which extends circumferentially along the connecting rod 52, and the inner ring of the sliding bearing 44 is disposed within the annular groove 525. In this way, the sliding bearing 44 and the connecting rod 52 can be engaged in a stop-fitting manner along the axis of the lead screw 21, thereby improving the synchronicity of the movement of the sliding bearing 44 and the connecting rod 52.

[0153] Please see Figure 16 , Figure 16 This is a schematic diagram of the structure of the sliding bearing 44 provided in an exemplary embodiment of this disclosure. In some embodiments, the sliding bearing 44 is an open bearing. In this way, the sliding bearing 44 can be either embedded in the connecting rod 52, or the opening can be enlarged to sleeve the sliding bearing 44 on the connecting rod 52, or it can be removed from the connecting rod 52, thereby improving the ease of installation and maintenance of the sliding bearing 44.

[0154] Please see Figure 15In some embodiments, the single-wheel steering gear 100 further includes an anti-rotation bearing 45. The anti-rotation bearing 45 is annularly disposed between the connecting rod 52 and the housing 10. At least a portion of the inner surface of the anti-rotation bearing 45 engages with the connecting rod 52 circumferentially with the lead screw 21. At least a portion of the outer circumferential surface of the anti-rotation bearing 45 engages with the housing 10 circumferentially with the lead screw 21. Thus, the anti-rotation bearing 45's engagement with the connecting rod 52 and the housing 10 circumferentially with the lead screw 21 prevents the connecting rod 52 from rotating, allowing the lead screw 21 to drive the connecting rod 52 and the steering knuckle fork 51 to move stably along the axis of the lead screw 21. Simultaneously, the anti-rotation bearing 45 radially supports the connecting rod 52. This improves the smoothness of the connecting rod 52's movement.

[0155] Please see Figures 17 to 19 , Figure 17 This is a schematic diagram of the structure of the connecting rod 52 provided in an exemplary embodiment of this disclosure. Figure 18 This is a schematic diagram of the anti-rotation bearing 45 provided in an exemplary embodiment of this disclosure. Figure 19 This is a partial structural schematic diagram of the housing 10 provided in an exemplary embodiment of this disclosure. In some embodiments, the outer surface of the connecting rod 52 is provided with a first plane 523. The housing 10 is provided with a second plane 15. The inner and outer surfaces of the anti-rotation bearing 45 are respectively provided with an inner plane 451 and an outer plane 452. The inner plane 451 is in contact with the first plane 523. The outer plane 452 is in contact with the second plane 15. In this way, the stop-fit ​​structure between the anti-rotation bearing 45, the housing 10, and the connecting rod 52 is simple and easy to manufacture, thereby reducing the manufacturing cost of the single-wheel steering gear 100.

[0156] The anti-rotation bearing 45 uses a radially supporting arc surface to support the connecting rod 52, and its inner plane 451 and outer plane 452 prevent rotation. This allows the anti-rotation bearing 45 to serve two functions, thereby reducing costs and contributing to the lightweight design of the single-wheel steering gear 100.

[0157] Specifically, the first plane 523 and the inner plane 451 are fitted with a small clearance, while the outer circumferential surface of the connecting rod 52 and the inner circumferential surface of the anti-rotation bearing 45 are fitted with a small clearance or transition fit. The second plane 15 and the outer plane 452 are fitted with an interference fit, while the outer circumferential surface of the anti-rotation bearing 45 and the inner circumferential surface of the housing 10 that is in contact with the outer circumferential surface of the anti-rotation bearing 45 are fitted with an interference fit. When the lead screw 21 is subjected to frictional force generated by the rotation of the roller 231, the lead screw 21 will tend to rotate. Since the anti-rotation bearing 45 and the housing 10 are fitted with an interference fit, the anti-rotation bearing 45 and the housing 10 are relatively fixed, and the inner plane 451 of the anti-rotation bearing 45 and the first plane 523 will abut against each other, thereby restricting the rotation of the lead screw 21. In this way, the possibility of relative rotation between the anti-rotation bearing and the housing 10 can be greatly reduced, thereby reducing the failure probability of the single-wheel steering gear 100 and improving the reliability of the single-wheel steering gear 100.

[0158] Specifically, at least one of the inner plane 451, the outer plane 452, the first plane 523, and the second plane 15 is provided.

[0159] Please see Figure 15 In some embodiments, a second damping pad 472 is provided between the housing 10 and the steering knuckle fork 51. The second damping pad 472 is connected to one of the steering knuckle fork 51 and the housing 10. In this way, the contact between the housing 10 and the steering knuckle can be buffered to reduce the impact noise generated when they contact.

[0160] Specifically, the second damping pad 472 is annular, which is sleeved on the connecting rod 52 and fixed on the steering knuckle fork 51.

[0161] Please see Figure 20 , Figure 20 yes Figure 4 An enlarged structural diagram of section F is shown. In some embodiments, the single-wheel steering gear 100 further includes a position sensor, which includes a synchronizing element 54 and an identification component 55. The synchronizing element 54 is disposed in the inner cavity 13 and moves synchronously with the lead screw 21. The identification component 55 is disposed on the housing 10 and is signal-connected to the controller of the drive device 30. The identification component 55 collects the position information of the synchronizing element 54 and sends the position information to the controller. The controller controls the operating state of the drive device 30 according to the position information.

[0162] Position sensors can be photoelectric position sensors, inductive position sensors, potentiometer position sensors, etc.

[0163] It is understood that the drive unit 30 includes a motor 32, a transmission mechanism 31, and a controller.

[0164] Specifically, a square groove 524 is provided on the connecting rod 52, and the synchronizing element 54 is disposed within the square groove 524. The synchronizing element 54 is connected to the connecting rod 52 by adhesive, or it can be fixed relative to the connecting rod by bolts or other means. The identification component 55 is disposed on the outside of the housing 10 and is located close to the synchronizing element 54. The identification component 55 collects the position information of the synchronizing element 54 and converts the position information into an electrical signal, which is then sent to the controller via the sensor wiring harness 50. The controller can issue corresponding instructions to the motor 32 based on the received position signal, causing the motor 32 to rotate forward, reverse, or stop.

[0165] In some embodiments, the synchronizing element 54 is magnetic, and the identification component 55 determines the position information of the synchronizing element 54 based on changes in the surrounding magnetic field. Thus, the position information of the lead screw 21 is determined by changes in magnetic field. Furthermore, the magnetic field is directly in contact with or connected to the object being detected, thereby avoiding problems such as mechanical wear and poor contact.

[0166] Synchronizer 54 is magnetic and generates a magnetic field. Synchronizer 54 moves with the lead screw 21, thereby changing the position of recognition component 55 within the magnetic field. Recognition component 55 can determine the position of the magnetic block by the change in the magnetic field, and simultaneously convert the position information into an electrical signal, which is then transmitted to the controller via sensor harness 50.

[0167] For example, the synchronizing element 54 is a magnet.

[0168] Specifically, the synchronizing element 54 is located inside the sliding bearing 44. In order to reduce the interference of the sliding bearing 44 on the magnetic field, the sliding bearing 44 is made of non-metallic material.

[0169] Please see Figures 1 to 4 In some embodiments, the drive device 30 includes a motor 32 and a transmission mechanism 31. The transmission mechanism 31 is disposed in the inner cavity 13. The motor 32 is disposed outside the housing 10. The output shaft 322 of the motor 32 passes through the housing 10. The output shaft 322 is connected to the ball screw assembly 20 via the transmission mechanism 31.

[0170] When the motor 32 is powered on, it drives the output shaft 322 to rotate forward or backward, thereby driving the rollers 231 of the ball screw assembly 20 to rotate through the transmission mechanism 31, so as to drive the ball screw 21 to move.

[0171] Please see Figure 3In some embodiments, the transmission mechanism 31 includes a driving pulley 312, a driven pulley 311, and a synchronous belt 313. The driving pulley 312 is sleeved on the output shaft 322. The driven pulley 311 is connected to the ball screw assembly 20. The two ends of the synchronous belt 313 are respectively sleeved on the driving pulley 312 and the driven pulley 311. It can be understood that the transmission mechanism 31 is a pulley transmission mechanism 31. The pulley transmission mechanism 31 transmits power by means of friction or meshing between the synchronous belt 313 and the driving pulley 312 and the driven pulley 311. Since the synchronous belt 313 has a certain degree of elasticity, it can have a buffering and vibration reduction effect, making the transmission process smoother and the noise lower.

[0172] Specifically, the output shaft 322 of the motor 32 drives the driven pulley 311 to rotate sequentially through the driving pulley 312 and the synchronous belt 313. The diameter of the driven pulley 311 is larger than that of the driving pulley 312, thereby achieving speed reduction and torque increase. Since the driven pulley 311 is connected to the planetary carrier 24, its rotation transmits torque in the circumferential direction, thereby driving the planetary carrier 24 to rotate. The planetary carrier 24 drives the rollers 231 to rotate around the lead screw 21 and rotate on their own axis, thereby pushing the lead screw 21 to move linearly.

[0173] The driven pulley 311 has a meshing tooth 314 in its middle that meshes with the synchronous belt 313. The synchronous belt 313 also has meshing teeth 314 on its inner side that mesh with both the driving pulley 312 and the driven pulley 311. The driving pulley 312 is press-fitted onto the output shaft 322 of the motor 32. The motor 32 drives the driving pulley 312 to rotate. Both the driving pulley 312 and the driven pulley 311 are engaged with the synchronous belt 313, thus the driving pulley 312 pulls the synchronous belt 313 to rotate, thereby driving the driven pulley 311 to rotate, which in turn drives the planetary carrier 24 connected to the driven pulley 311 to rotate. The planetary carrier 24 drives the rollers 231 to rotate around the lead screw 21 and rotate on their own axis. Since the lead screw 21 meshes with the roller 231 through helical teeth, the rotation of the roller 231 will push the lead screw 21 to move. Due to the friction between the roller 231 and the lead screw 21, the roller 231 rotates along its own axis. At the same time, there is friction between the roller 231 and the nut 22, causing the nut 22 to rotate. The roller 231 and the lead screw 21, as well as the roller 231 and the nut 22, all have equidistant meshing teeth 314.

[0174] Please see Figure 3 as well as Figure 21 , Figure 21This is a schematic diagram of the timing belt 313 adjustment provided in an exemplary embodiment of this disclosure. In some embodiments, the single-wheel steering gear 100 further includes a connecting bolt 56. A mounting through hole 16 and an arc-shaped hole 17 are provided on the housing 10. The arc-shaped hole 17 extends about the axis of the mounting through hole 16. A positioning boss 321 is provided on the housing of the motor 32. The axis of the positioning boss 321 is offset relative to the output shaft 322 of the motor 32. The positioning boss 321 is inserted into the mounting through hole 16. The end of the shank of the connecting bolt 56 passes through the arc-shaped hole 17 and is threadedly connected to the housing of the motor 32.

[0175] A second sealing ring 492 is provided between the end face of the motor 32 facing the drive pulley 312 and the outer casing 10. The second seal is annularly disposed on the output shaft 322 of the motor 32, thereby facilitating the sealing of the inner cavity 13.

[0176] It can be understood that there is a gap d between the axis of the positioning boss 321 and the axis of the output shaft 322 of the motor 32, so that the axis of the positioning boss 321 is offset relative to the output shaft 322 of the motor 32.

[0177] It is understandable that the tension of the timing belt 313 can be changed by adjusting the center distance between the driving pulley 312 and the driven pulley 311, thereby allowing the timing belt 313 to be in a suitable installation state and improving its service life.

[0178] Specifically, the implementation method for adjusting the center distance between the driving pulley 312 and the driven pulley 311 is as follows: A positioning boss 321, eccentric to the output shaft 322 of the motor 32, is provided on the motor 32. A corresponding mounting through hole 16 and an arc-shaped hole 17 extending around the axis of the mounting through hole 16 are provided on the housing 10. During assembly, the positioning boss 321 is first inserted into the mounting through hole 16, and then the motor 32 is rotated, causing the positioning boss 321 to rotate relative to the housing 10. Since the output shaft 322 of the motor 32 is eccentric to the positioning boss 321, that is, the output shaft 322 of the motor 32 is eccentric to the mounting through hole 16, the position of the output shaft 322 of the motor 32 in the mounting through hole 16 can be adjusted by rotating the positioning boss 321, thereby adjusting the center distance between the driving pulley 312 and the driven pulley 311 to adjust the tension of the synchronous belt 313. After rotating the motor 32 to the appropriate position, the end of the connecting bolt 56 passes through the arc-shaped hole 17 and is screwed into the threaded hole of the motor 32 housing 10 to fix the motor 32 to the housing 10. Figure 21 As shown, Figure 21 Figure (e) shows the center distance a1 between the output shaft 322 (i.e., the driving pulley 312) and the driven pulley 311 of the motor 32 when the motor 32 rotates to the first position. Figure 21Figure (f) shows that when the motor 32 rotates to the second position, the center distance between the output shaft 322 of the motor 32 (i.e., the driving pulley 312) and the driven pulley 311 is a2. In this way, the center distance between the driving pulley 312 and the driven pulley 311 can be adjusted.

[0179] In this configuration, the output shaft 322 of the motor 32 transmits power to the driven pulley 311 sequentially via the driving pulley 312 and the synchronous belt 313. The diameter of the driven pulley 311 is larger than that of the driving pulley 312, enabling speed reduction and torque increase. The synchronous belt 313 drives the driven pulley 311 to rotate, and the driven pulley 311 can transmit torque to the planetary carrier 24 in the circumferential direction, thereby driving the planetary carrier 24 to rotate, causing the roller 231 to rotate around the lead screw 21, thus driving the lead screw 21 to move linearly.

[0180] Please see Figure 22 , Figure 22 This is an exploded view of the housing 10 provided in an exemplary embodiment of this disclosure. In some embodiments, the housing 10 includes a first housing member 11 and a second housing member 12. The first housing member 11 and the second housing member 12 are connected to define an inner cavity 13. The first housing member 11 and the second housing member 12 are connected by bolts. Both the first housing member 11 and the second housing member 12 are provided with positioning pin holes 18. The two ends of the positioning pin shaft 19 are respectively inserted into the positioning pin holes 18 of the first housing member 11 and the second housing member 12 to install and position the first housing member 11 and the second housing member 12, thereby improving the structural reliability of the housing 10, which is beneficial to improving transmission smoothness and extending service life.

[0181] According to a second aspect of this application, a vehicle is provided, the vehicle having at least two of the aforementioned single-wheel steering units 100.

[0182] It is understood that the vehicle may be a gasoline-powered vehicle, a plug-in hybrid electric vehicle, or a new energy vehicle, etc., and this disclosure does not make any specific restrictions.

[0183] It is understood that at least two steering gears are symmetrically arranged on the left and right sides of the vehicle along the centerline. The two steering gears can be indirectly or directly connected to the left wheel 601 and the right wheel 602 respectively, so as to control the rotation of the left wheel 601 and the right wheel 602 respectively, so as to achieve different steering control effects, thereby reducing the turning radius of the vehicle, improving the steering stability of the vehicle, shortening the braking distance of the vehicle, and improving the driving control of the vehicle.

[0184] It is understood that the vehicle includes the aforementioned single-wheel steering system 100, and the vehicle has all the beneficial effects of the aforementioned single-wheel steering system 100, which will not be repeated here.

[0185] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0186] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or connections that allow for communication; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0187] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process or product that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such a process or product.

[0188] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0189] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0190] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A single-wheel steering system (100), characterized in that, include: The outer shell (10) has an inner cavity (13); A roller screw assembly (20) is rotatably disposed in the inner cavity (13), and the roller screw assembly (20) includes a screw (21); as well as A drive device (30) is at least partially disposed in the inner cavity (13), and the drive device (30) is connected to the roller screw assembly (20) to drive the screw (21) to move. One end of the lead screw (21) is configured to be connected to a wheel.

2. The single-wheel steering system (100) according to claim 1, characterized in that, The roller screw assembly (20) also includes: Nut (22) is fitted onto the lead screw (21); A roller assembly (23) is annularly disposed between the nut (22) and the lead screw (21), wherein the meshing teeth of the roller assembly (23) mesh with the helical teeth of the lead screw (21) and the meshing teeth of the nut (22), respectively; and Planetary carrier (24) is rotatably mounted in the inner cavity (13) and sleeved on the lead screw (21); The nut (22) and the roller assembly (23) are both rotatably connected to the planetary carrier (24); The drive unit (30) is connected to the planetary carrier (24) via a transmission.

3. The single-wheel steering system (100) according to claim 2, characterized in that, The planetary carrier (24) includes two planetary subcarriers (241), both of which are mounted on the lead screw (21) and rotatably connected to the outer shell (10). The nut (22) and the roller assembly (23) are located between the two planetary subcarriers (241). The two ends of the nut (22) are rotatably connected to the two planetary subcarriers (241), and the two ends of the roller assembly (23) are rotatably connected to the two planetary subcarriers (241).

4. The single-wheel steering system (100) according to claim 3, characterized in that, The drive device (30) is a belt drive device. The driven pulley (311) of the drive device (30) is sleeved on the nut (22). The two ends of the driven pulley (311) are respectively connected to the two planetary subcarriers (241).

5. The single-wheel steering system (100) according to claim 4, characterized in that, The passive pulley (311) is engaged with the planetary subcarrier (241).

6. The single-wheel steering system (100) according to claim 5, characterized in that, A snap-fit ​​block (2411) is provided on the end face of the planetary subcarrier (241) facing the passive pulley (311). A snap-fit ​​hole (2413) is provided on the snap-fit ​​block (2411). An elastic buckle (3111) is provided on the end face of the passive pulley (311). The end of the elastic buckle (3111) away from the passive pulley (311) passes through the snap-fit ​​hole (2413) and engages with the snap-fit ​​hole (2413) for blocking.

7. The single-wheel steering system (100) according to claim 4, characterized in that, The passive pulley (311) is inserted into the planetary subcarrier (241).

8. The single-wheel steering system (100) according to claim 7, characterized in that, A plurality of first slots (3114) are provided on the end face of the passive pulley (311), and the plurality of first slots (3114) are arranged sequentially along the circumference of the lead screw (21). A plurality of first blocks (2414) are provided on the end face of the planetary carrier (241) facing the passive pulley (311), and the plurality of first blocks (2414) are respectively inserted into the plurality of first slots (3114).

9. The single-wheel steering system (100) according to any one of claims 3-8, characterized in that, A first groove (221) is provided on the inner circumferential surface of the nut (22); and / or, A second groove (222) is provided on the outer peripheral surface of the nut (22).

10. The single-wheel steering system (100) according to any one of claims 3-8, characterized in that, The roller assembly (23) includes a plurality of rollers (231) arranged sequentially along the circumference of the lead screw (21). The meshing teeth in the middle of the rollers (231) mesh with the helical teeth of the lead screw (21), and the meshing teeth at both ends of the rollers (231) mesh with the meshing teeth of the nut (22).

11. The single-wheel steering system (100) according to claim 10, characterized in that, Each of the rollers (231) has two planetary carriers (241) inserted into its two ends respectively, and is in clearance fit with the planetary carriers (241).

12. The single-wheel steering system (100) according to any one of claims 3-8, characterized in that, Along the axial direction of the lead screw (21), a first axial bearing (41) is provided between each of the planetary subcarriers (241) and the housing (10).

13. The single-wheel steering system (100) according to claim 12, characterized in that, A gasket (46) is provided between the housing (10) and at least one of the first axial bearings (41) along the axial direction of the lead screw (21).

14. The single-wheel steering system (100) according to any one of claims 3-8, characterized in that, Along the axial direction of the lead screw (21), a second axial bearing (42) is provided between each planetary carrier (241) and the nut (22); along the radial direction of the lead screw (21), a radial bearing (43) is provided between each planetary carrier (241) and the housing (10).

15. The single-wheel steering system (100) according to claim 1, characterized in that, The single-wheel steering system (100) also includes a steering knuckle fork (51) connected to the lead screw (21) and configured to connect to the wheel.

16. The single-wheel steering system (100) according to claim 15, characterized in that, The single-wheel steering gear (100) also includes a connecting rod (52), which is disposed between the lead screw (21) and the steering knuckle fork (51), and the steering knuckle fork (51) is connected to the lead screw (21) through the connecting rod (52).

17. The single-wheel steering system (100) according to claim 16, characterized in that, The connecting rod (52) has a connecting threaded hole (521) at one end facing the lead screw (21). The end of the lead screw (21) near the steering knuckle fork (51) is inserted into the connecting threaded hole (521) and threadedly connected to the connecting threaded hole (521).

18. The single-wheel steering system (100) according to claim 17, characterized in that, The lead screw (21) has a smooth shaft section (211), which is threadedly riveted to the connecting threaded hole (521).

19. The single-wheel steering system (100) according to claim 16, characterized in that, A limiting boss (522) is provided on the outer peripheral surface of the connecting rod (52), and a limiting step (14) is provided on the inner wall of the housing (10). The limiting step (14) is located on the side of the limiting boss (522) close to the steering knuckle fork (51). The outer diameter of the limiting boss (522) is larger than the inner diameter of the limiting step (14).

20. The single-wheel steering system (100) according to claim 19, characterized in that, A first damping pad (471) is provided between the limiting boss (522) and the limiting step (14), and the first damping pad (471) is connected to one of the limiting boss (522) and the limiting step (14).

21. The single-wheel steering system (100) according to any one of claims 16-20, characterized in that, The single-wheel steering gear (100) also includes an end bolt (48), the end of which passes through the steering knuckle fork (51) and is threaded to the connecting rod (52).

22. The single-wheel steering system (100) according to claim 21, characterized in that, A countersunk plate (511) is provided at one end of the steering knuckle fork (51) facing the connecting rod (52), and the end of the connecting rod (52) away from the lead screw (21) is inserted into the countersunk plate (511).

23. The single-wheel steering system (100) according to claim 21, characterized in that, A first sealing ring (491) is provided between the steering knuckle fork (51) and the connecting rod (52), and the outer surface of the first sealing ring (491) abuts against the steering knuckle fork (51) and the connecting rod (52) respectively.

24. The single-wheel steering system (100) according to any one of claims 16-20, characterized in that, The single-wheel steering gear (100) also includes a telescopic tube (53), a portion of the connecting rod (52) and the steering knuckle fork (51) are located outside the housing (10), the middle part of the telescopic tube (53) is sleeved on the connecting rod (52), one end of the telescopic tube (53) is sleeved on the end of the housing (10) near the steering knuckle fork (51), and the other end of the telescopic tube (53) is sleeved on the steering knuckle fork (51).

25. The single-wheel steering system (100) according to claim 24, characterized in that, The telescopic tube (53) is a corrugated tube.

26. The single-wheel steering system (100) according to any one of claims 16-20, characterized in that, The single-wheel steering gear (100) also includes a sliding bearing (44), which is arranged in a ring between the connecting rod (52) and the housing (10). The inner ring of the sliding bearing (44) is in contact with the connecting rod (52), and the outer ring of the sliding bearing (44) is in contact with the housing (10).

27. The single-wheel steering system (100) according to claim 26, characterized in that, The outer circumferential surface of the connecting rod (52) is provided with an annular groove (525), which extends circumferentially along the connecting rod (52), and the inner ring of the sliding bearing (44) is located in the annular groove (525).

28. The single-wheel steering system (100) according to claim 27, characterized in that, The sliding bearing (44) is an open bearing.

29. The single-wheel steering system (100) according to any one of claims 16-20, characterized in that, The single-wheel steering gear (100) further includes an anti-rotation bearing (45), which is arranged in a ring between the connecting rod (52) and the housing (10). At least a portion of the inner surface of the anti-rotation bearing (45) is in a stop-fitting engagement with the connecting rod (52) along the circumference of the lead screw (21), and at least a portion of the outer circumferential surface of the anti-rotation bearing (45) is in a stop-fitting engagement with the housing (10) along the circumference of the lead screw (21).

30. The single-wheel steering system (100) according to claim 29, characterized in that, The outer surface of the connecting rod (52) is provided with a first plane (523), the outer shell (10) is provided with a second plane (15), the inner surface and outer surface of the anti-rotation bearing (45) are respectively provided with an inner plane (451) and an outer plane (452), the inner plane (451) is in contact with the first plane (523), and the outer plane (452) is in contact with the second plane (15).

31. The single-wheel steering system (100) according to any one of claims 15-20, characterized in that, A second damping pad (472) is provided between the housing (10) and the steering knuckle fork (51), and the second damping pad (472) is connected to one of the steering knuckle fork (51) and the housing (10).

32. The single-wheel steering system (100) according to any one of claims 1-8 or any one of claims 15-20, characterized in that, The single-wheel steering gear (100) also includes a position sensor, which includes a synchronizing element (54) and an identification component (55). The synchronizing element (54) is disposed in the inner cavity (13) and moves synchronously with the lead screw (21). The identification component (55) is disposed on the outer shell (10) and is connected to the controller signal of the drive device (30). The identification component (55) collects the position information of the synchronizing element (54) and sends the position information to the controller. The controller controls the working state of the drive device (30) according to the position information.

33. The single-wheel steering system (100) according to claim 32, characterized in that, The synchronization element (54) is magnetic, and the identification component (55) determines the position information of the synchronization element (54) based on the change of the magnetic field.

34. The single-wheel steering system (100) according to any one of claims 1-8 or any one of claims 15-20, characterized in that, The drive device (30) includes a motor (32) and a transmission mechanism (31). The transmission mechanism (31) is located in the inner cavity (13), and the motor (32) is located outside the outer shell (10). The output shaft (322) of the motor (32) passes through the outer shell (10), and the output shaft (322) is connected to the ball screw assembly (20) through the transmission mechanism (31).

35. The single-wheel steering system (100) according to claim 34, characterized in that, The transmission mechanism (31) includes a drive pulley (312), a driven pulley (311), and a timing belt (313). The drive pulley (312) is sleeved on the output shaft (322), the driven pulley (311) is connected to the ball screw assembly (20), and the two ends of the timing belt (313) are respectively sleeved on the drive pulley (312) and the driven pulley (311).

36. The single-wheel steering system (100) according to claim 35, characterized in that, The single-wheel steering gear (100) also includes a connecting bolt (56), and the housing (10) is provided with a mounting through hole (16) and an arc-shaped hole (17), the arc-shaped hole (17) extending around the axis of the mounting through hole (16); A positioning boss (321) is provided on the housing of the motor (32). The axis of the positioning boss (321) is offset relative to the output shaft (322) of the motor (32). The positioning boss (321) is inserted into the mounting through hole (16). The end of the rod of the connecting bolt (56) passes through the arc-shaped hole (17) and is threadedly connected to the housing of the motor (32).

37. The single-wheel steering system (100) according to any one of claims 1-8 or any one of claims 15-20, characterized in that, The outer shell (10) includes a first shell member (11) and a second shell member (12), which are connected to define the inner cavity (13).

38. A vehicle, characterized in that, It includes at least two single-wheel steering systems (100) as claimed in any one of claims 1-37.

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