Limiting device, steer-by-wire system and vehicle

Abstract

The utility model relates to the technical field of vehicles, and discloses a limiting device, a steer-by-wire system and a vehicle, and the limiting device comprises a steering shaft, at least one rotating piece and two rotating limiting pieces. The at least one rotating piece is sequentially and rotatably arranged on the steering shaft in a sleeving mode in the axial direction of the steering shaft, the rotating piece is provided with a second limiting part, and the second limiting part on the rotating piece located at the first end in the axial direction of the steering shaft can abut against or be separated from the first limiting part in the circumferential direction of the steering shaft. The second limiting parts on any two adjacent rotating pieces can abut against or be separated from each other in the circumferential direction of the steering shaft. The two rotation limiting pieces are arranged in the circumferential direction of the steering shaft in a spaced mode and used for limiting the rotation range of the second limiting part on the rotating piece located at the second end in the axial direction of the steering shaft. By means of the arrangement, the rotation angle range of the steering shaft is limited, rotation resistance torque can be generated on the steering wheel under the power-off working condition of an electric control system of the steer-by-wire system or when faults occur, the number of rotation turns of the steering wheel is limited, and a clock spring is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicles, and in particular to a limit device, a wire-controlled steering system and a vehicle. Background Art

[0002] Since the vehicle's steer-by-wire system eliminates the intermediate shaft, there is no mechanical rotation transmission between the steering control mechanism and the steering actuator. When powered on, the steer-by-wire system limits the steering wheel angle through software, but when the power is off or the road sensing module of the steer-by-wire system fails, the steering wheel angle limit function fails, causing the steering wheel to turn left and right at will, affecting the reliability of the steering system and easily damaging the clock spring.

[0003] Therefore, there is an urgent need for a limit device, a wire-controlled steering system and a vehicle to solve the above problems. Utility Model Content

[0004] Based on the above problems, the purpose of the utility model is to provide a limit device, a wire-controlled steering system and a vehicle, which can limit the rotation of the steering shaft within a limited angle range, protect the clock spring, and improve the driving safety of the vehicle.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] In a first aspect, a limiting device is provided, comprising:

[0007] A steering shaft, wherein the steering shaft is provided with a first limiting portion;

[0008] At least one rotating member is rotatably sleeved on the steering shaft in sequence along the axial direction of the steering shaft, the rotating member is provided with a second limiting portion, the second limiting portion on the rotating member located at the first end of the axial direction of the steering shaft can abut or separate from the first limiting portion along the circumferential direction of the steering shaft, and the second limiting portions on any two adjacent rotating members can abut or separate from each other along the circumferential direction of the steering shaft;

[0009] Two rotation limiting members are arranged at intervals along the circumferential direction of the steering shaft and are used to limit the rotation range of the second limiting portion on the rotating member located at the second axial end of the steering shaft.

[0010] As a preferred solution of the position limiting device of the utility model, the position limiting device further comprises a fixed sleeve, the fixed sleeve is sleeved on the steering shaft and at least one of the rotating parts at intervals, and the two rotating limiting parts are arranged on the inner circumference of the fixed sleeve.

[0011] As a preferred solution of the position limiting device of the utility model, the position limiting device further comprises a fixing ring sleeved on the steering shaft, and the first position limiting portion is provided with the fixing ring.

[0012] As a preferred solution of the limiting device of the utility model, the steering shaft is provided with a first limiting structure, and the fixing ring is provided with a second limiting structure, and the first limiting structure and the second limiting structure cooperate to limit the fixing ring from rotating relative to the steering shaft.

[0013] As a preferred embodiment of the limiting device of the present invention, the first limiting structure includes a first limiting surface arranged on the outer peripheral wall of the steering shaft, and the second limiting structure includes a second limiting surface arranged on the inner peripheral wall of the fixing ring, and the first limiting surface is in contact with the second limiting surface.

[0014] As a preferred solution of the limiting device of the utility model, the steering shaft is provided with a first shaft shoulder, and the fixing ring is axially limited to the steering shaft by the first shaft shoulder.

[0015] As a preferred embodiment of the limiting device of the utility model, the steering shaft is provided with a second shoulder, and the limiting device also includes a retaining ring, which is clamped on the steering shaft and spaced apart from the second shoulder, and at least one of the rotating parts is axially limited to the steering shaft by the second shoulder and the retaining ring.

[0016] As a preferred solution of the position limiting device of the utility model, the rotating member is rotatably mounted on the steering shaft through a bearing;

[0017] Alternatively, the outer circumferential surface of the steering shaft and / or the inner circumferential surface of the rotating member is provided with a lubricating layer.

[0018] As a preferred solution of the position limiting device of the present invention, buffer layers are provided on both sides of the first position limiting portion, the second position limiting portion, and / or the rotation limiting member along the circumferential direction of the steering shaft.

[0019] In a second aspect, a steer-by-wire system is provided, comprising a steering wheel and the position limiting device as described above, wherein the steering wheel is connected to a steering shaft of the position limiting device.

[0020] In a third aspect, a vehicle is provided, comprising the steer-by-wire system as described above, wherein the steer-by-wire system is drivingly connected to the wheels of the vehicle.

[0021] The beneficial effects of the utility model are:

[0022] The utility model provides a limit device, a wire-controlled steering system and a vehicle, wherein the steering shaft is fixedly connected to the steering wheel, and when the steering wheel drives the steering shaft to rotate until the first limit part abuts against the second limit part of the rotating member at the first end of the steering shaft, the steering shaft drives the rotating member to rotate synchronously; when the rotating member rotates until the second limit part on it contacts the second limit part on the rotating member adjacent to it, the two rotating members rotate synchronously with the steering shaft until the second limit part of the rotating member at the second end of the steering shaft abuts against one of the two limit parts, and the steering shaft stops rotating. Since the two limit parts are arranged at intervals along the circumferential direction of the steering shaft, the rotating member at the second end of the steering shaft can only rotate within the range limited by the two limit parts, thereby limiting the angle range of the steering shaft's forward and reverse rotation, and generating a rotation resistance torque on the steering wheel under the electrical condition of the electronic control system of the wire-controlled steering system or when a fault occurs, so as to limit the number of rotations of the steering wheel, protect the clock spring, and improve the driving safety of the vehicle. In addition, the rotation angle range of the steering shaft can be changed by increasing or decreasing the number of rotating parts or changing the distance between two rotation limiting parts. The structural design is simpler and easier to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0024] Figure 1 It is a structural schematic diagram of a position limiting device provided in a specific embodiment of the utility model;

[0025] Figure 2 It is a first exploded schematic diagram of the limiting device provided in a specific embodiment of the utility model;

[0026] Figure 3 It is a structural schematic diagram of a limit cover provided in a specific embodiment of the utility model;

[0027] Figure 4 It is a structural schematic diagram of a steering shaft provided in a specific embodiment of the utility model;

[0028] Figure 5 It is a second exploded schematic diagram of the limiting device provided in the specific implementation mode of the utility model.

[0029] In the figure:

[0030] 1-steering shaft; 2-rotating part; 3-fixed sleeve; 4-fixed ring; 5-bearing; 6-retaining ring;

[0031] 11-first shaft section; 12-second shaft section; 13-third shaft section; 14-first shaft shoulder; 15-second shaft shoulder;

[0032] 121 first limiting surface; 131- mounting groove;

[0033] 21- second limiting portion;

[0034] 31-Restricted rotation parts;

[0035] 41 - first limiting portion; 42 - second limiting surface. DETAILED DESCRIPTION

[0036] In order to make the technical problems solved by the utility model, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the utility model will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0037] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] like Figure 1 and Figure 2 As shown, this embodiment provides a limit device that can limit the steering shaft 1 to rotate within a limited angle range to prevent the steering wheel from rotating arbitrarily after power failure and damaging the clock spring. The limit device includes a steering shaft 1, at least one rotating member 2 and two rotation limiting members 31.

[0040] Among them, see Figure 1 , Figure 2 and Figure 3 The steering shaft 1 is provided with a first position-limiting portion 41, at least one rotating member 2 is rotatably sleeved on the steering shaft 1 in sequence along the axial direction of the steering shaft 1, and the rotating member 2 is provided with a second position-limiting portion 21. The second position-limiting portion 21 on the rotating member 2 at the first axial end of the steering shaft 1 can abut or separate from the first position-limiting portion 41 along the circumferential direction of the steering shaft 1, and the second position-limiting portions 21 on any two adjacent rotating members 2 can abut or separate from each other along the circumferential direction of the steering shaft 1. Two rotation-limiting members 31 are arranged at intervals along the circumferential direction of the steering shaft 1, and are used to limit the rotation range of the second position-limiting portion 21 on the rotating member 2 at the second axial end of the steering shaft 1.

[0041] In the limiting device provided in this embodiment, the steering shaft 1 is fixedly connected with the steering wheel. When the steering wheel drives the steering shaft 1 to rotate until the first limiting portion 41 abuts against the second limiting portion 21 of the rotating member 2 at the first end of the steering shaft 1, the steering shaft 1 drives the rotating member 2 to rotate synchronously; when the rotating member 2 rotates until the second limiting portion 21 on it contacts the second limiting portion 21 on the adjacent rotating member 2, the two rotating members 2 rotate synchronously with the steering shaft 1 until the second limiting portion 21 of the rotating member 2 at the second end of the steering shaft 1 abuts against one of the two limiting members 31, and the steering shaft 1 stops rotating. Since the two limiting members 31 are arranged at intervals along the circumferential direction of the steering shaft 1, the rotating member 2 at the second end of the steering shaft 1 can only rotate within the range limited by the two limiting members 31, thereby limiting the angular range of the forward and reverse rotation of the steering shaft 1, and generating a rotation resistance torque to the steering wheel under the electrical condition of the electronic control system of the wire control steering system or when a fault occurs, so as to limit the number of rotations of the steering wheel, protect the clock spring, and improve the driving safety of the vehicle.

[0042] Furthermore, if one wants to change the limited rotation angle range of the steering shaft 1, the limited rotation angle range of the steering shaft 1 can be changed by simply increasing or decreasing the number of rotating parts 2 or changing the distance between the two rotation limiting parts 31. The structural design is simple and easier to process and implement.

[0043] Optionally, see Figure 2 and Figure 3 The limiting device further comprises a fixed sleeve 3, which is sleeved on the steering shaft 1 and at least one rotating member 2 at intervals, and two rotation limiting members 31 are arranged on the inner circumference of the fixed sleeve 3. The fixed sleeve 3 is fixed and connected to the fixed part of the vehicle to limit the rotation angle of the steering shaft 1. Since the fixed sleeve 3 can wrap the steering shaft 1 and the rotating member 2, the exterior of the limiting device is more neat and beautiful.

[0044] Exemplarily, the fixed sleeve 3 and the two rotation-limiting members 31 are integrally formed, so that the number of parts is small and the assembly is simple. Optionally, the two rotation-limiting members 31 are arc-shaped convex strips convexly arranged on the inner wall of the fixed sleeve 3.

[0045] Optionally, see Figure 1 and Figure 2 The limiting device also includes a fixing ring 4 sleeved on the steering shaft 1, and a first limiting portion 41 is arranged on the fixing ring 4. The fixing ring 4 and the steering shaft 1 can be detachably installed. The detachable design makes it easier to process and manufacture parts, thereby reducing the processing cost. Exemplarily, the first limiting portion 41 is a limiting protrusion convexly arranged on the fixing ring 4, and the protruding height of the limiting protrusion is lower than the inner wall of the fixing sleeve 3 to prevent the limiting protrusion from interfering with the fixing sleeve 3 during rotation. The two opposite side surfaces of the limiting protrusion along the circumference of the fixing ring 4 are abutment surfaces. By changing the angle between the above two side surfaces, the rotation angle range of the steering shaft 1 can also be fine-tuned. Therefore, the first limiting portion 41 and the steering shaft 1 are designed independently of each other, and the angle between the two side surfaces of the first limiting portion 41 can be flexibly changed.

[0046] In other embodiments, the fixing ring 4 , the first limiting portion 41 and the steering shaft 1 may also be integrally formed.

[0047] Optionally, the steering shaft 1 is provided with a first limiting structure, and the fixing ring 4 is provided with a second limiting structure, and the first limiting structure and the second limiting structure cooperate to limit the rotation of the fixing ring 4 relative to the steering shaft 1 to ensure that the fixing ring 4 is firmly installed on the steering shaft 1.

[0048] Optionally, see Figure 2 and Figure 4 The first limiting structure includes a first limiting surface 121 provided on the outer peripheral wall of the steering shaft 1, and the second limiting structure includes a second limiting surface 42 provided on the inner peripheral wall of the fixing ring 4, and the first limiting surface 121 is in contact with the second limiting surface 42. In this embodiment, the fixing ring 4 is installed on the steering shaft 1 by interference fit, so that the first limiting surface 121 and the second limiting surface 42 are interference fit, which is simple to assemble and can ensure the installation firmness of the fixing ring 4, preventing the fixing ring 4 from rotating relative to the steering shaft 1. Furthermore, the first limiting surface 121 and the second limiting surface 42 are both planes, and the limiting method of plane contact is more stable, which can further prevent the fixing ring 4 from rotating relative to the steering shaft 1.

[0049] Exemplarily, a first limiting surface 121 is provided on each side of the steering shaft 1 which is symmetrical about its axis. Correspondingly, two second limiting surfaces 42 are symmetrically provided in the fixing ring 4. The two first limiting surfaces 121 correspond to the two second limiting surfaces 42 in a one-to-one manner, thereby further improving the connection stability between the fixing ring 4 and the steering shaft 1.

[0050] In other embodiments, the first limiting structure may be a keyway disposed on the steering shaft 1, and the second limiting structure may be a flat key or a spline disposed on the fixing ring 4, and the circumferential limiting of the fixing ring 4 on the steering shaft 1 is achieved by cooperating between the flat key or the spline and the keyway.

[0051] Optionally, see Figure 4 The steering shaft 1 is provided with a first shoulder 14, and the fixing ring 4 is axially limited to the steering shaft 1 by the first shoulder 14. That is, after the fixing ring 4 is sleeved on the steering shaft 1, its end face abuts against the first shoulder 14 to prevent the fixing ring 4 from axial displacement.

[0052] Further, see Figure 4 The steering shaft 1 is provided with a second shoulder 15, see Figure 1 The limiting device further includes a retaining ring 6, which is clamped on the steering shaft 1 and spaced apart from the second shaft shoulder 15. At least one rotating member 2 is axially limited on the steering shaft 1 by the second shaft shoulder 15 and the retaining ring 6. That is, one side of the rotating member 2 is limited by the second shaft shoulder 15, and the other side is limited by the retaining ring 6, thereby preventing the rotating member 2 from axially shifting on the steering shaft 1.

[0053] Specifically, see Figure 4 The steering shaft 1 includes a first shaft section 11, a second shaft section 12 and a third shaft section 13 connected to each other. The diameter of the second shaft section 12 is smaller than that of the first shaft section 11, and the diameter of the third shaft section 13 is smaller than that of the second shaft section 12, so as to form the above-mentioned first shaft shoulder 14 at the connection between the first shaft section 11 and the second shaft section 12, and form the above-mentioned second shaft shoulder 15 at the connection between the second shaft section 12 and the third shaft section 13. Further, the first limiting surface 121 is provided on the second shaft section 12, and the fixing ring 4 is installed on the second shaft section 12. The end of the third shaft section 13 is provided with a mounting groove 131, the retaining ring 6 is clamped in the mounting groove 131, and the rotating member 2 is installed on the third shaft section 13.

[0054] Optionally, see Figure 1 and Figure 2 , there are three rotating members 2, and the three rotating members 2 are arranged in sequence along the axial direction of the steering shaft 1. The rotating member 2 closest to the first limiting portion 41 among the three rotating members 2 has the largest diameter, and the second limiting portions 21 of the three rotating members 2 are all arranged flush with the first limiting portion 41. The three rotating members 2 are arranged in sequence along the axial direction to reduce the radial size of the limiting device as a whole, thereby reducing the radial installation space required for the limiting device. The second limiting portions 21 of the three rotating members 2 are arranged flush, which can prevent the rotating member 2 from interfering with the fixed sleeve 3 when rotating, thereby improving the smoothness of rotation. Designing the rotating member 2 closest to the first limiting portion 41 to have the largest diameter can increase the structural strength of the rotating member 2 and improve the overall structural stability of the limiting device.

[0055] Exemplarily, the second limiting portion 21 on the rotating member 2 with the largest diameter includes a first protrusion and a second protrusion protruding on both sides of the rotating member 2 along the axial direction, the first protrusion and the second protrusion are symmetrically arranged, the first protrusion is used to contact the first limiting portion 41, and the second protrusion is used to contact the second limiting portion 21 on the adjacent rotating member 2, or to contact the rotation limiting member 31.

[0056] In an alternative embodiment, see Figure 5 The rotating member 2 is rotatably mounted on the steering shaft 1 through the bearing 5. The bearing 5 can reduce the rotation resistance between the rotating member 2 and the steering shaft 1 and improve the smoothness of rotation. Specifically, the inner ring of the bearing 5 is fixed to the steering shaft 1, and the outer ring of the bearing 5 is fixedly connected to the rotating member 2. Such an arrangement can reduce the axial size of the entire limiting device and reduce the axial installation space required for the limiting device.

[0057] Exemplarily, when three rotating members 2 are provided, the three rotating members 2 are all rotatably mounted on the steering shaft 1 via corresponding bearings 5 ​​.

[0058] In other embodiments, a thrust bearing may be provided between two adjacent rotating members 2, so as to reduce the overall radial dimension of the limiting device.

[0059] In another optional embodiment, Figure 2 As shown, the rotating member 2 is installed on the steering shaft 1 by a clearance fit, and a lubricating layer is provided on the outer circumference of the steering shaft 1 and / or the inner circumference of the rotating member 2. That is, the rotating member 2 and the steering shaft 1 are rotationally fitted through the lubricating layer, and the rotating member 2 and the steering shaft 1 can also be rotatably installed. For example, lithium-based grease can be coated on the steering shaft 1 and / or the rotating member 2 to form a lubricating layer.

[0060] Optionally, a buffer layer is provided on both sides of the first limiting portion 41, the second limiting portion 21 and / or the rotation limiting member 31 along the circumferential direction of the steering shaft 1, and the buffer layer is used to buffer the force when the second limiting portion 21 contacts the first limiting portion 41, two adjacent second limiting portions 21, and the second limiting portion 21 contacts the limiting member 31. That is, during the rotation of the steering shaft 1, the buffer layer can buffer and absorb the force when the first limiting portion 41 collides with the second limiting portion 21, when two adjacent second limiting portions 21 collide, and when the second limiting portion 21 collides with the rotation limiting member 31, so as to prevent noise from being generated by the collision, thereby avoiding noise from occurring during steering.

[0061] Exemplarily, the buffer layer is a rubber pad or a plastic film, which is arranged at the position where the first limiting portion 41 contacts the second limiting portion 21, the position where the second limiting portions 21 of two adjacent rotating members 2 contact, and the position where the second limiting portion 21 contacts the rotation limiting member 31, and can be fixed by bonding.

[0062] The working process of the limiting device provided in this embodiment is as follows:

[0063] See also Figure 1 In the orientation, taking the three rotating members 2 installed on the steering shaft 1 as an example, when the steering wheel rotates, the steering shaft 1 drives the fixed ring 4 thereon to rotate synchronously in the clockwise direction; when the steering shaft 1 rotates to the point where the first limiting portion 41 contacts the second limiting portion 21 on the first rotating member 2, the steering shaft 1 drives the first rotating member 2 to rotate synchronously; when the second limiting portion 21 of the first rotating member 2 contacts the second limiting portion 21 of the second rotating member 2, the steering shaft 1 drives the second rotating member 2 to rotate synchronously; when the second limiting portion 21 of the second rotating member 2 contacts the second limiting portion 21 of the third rotating member 2, the steering shaft 1 drives the third rotating member 2 to rotate synchronously; when the second limiting portion 21 of the third rotating member 2 rotates with the steering shaft 1 to contact a rotation limiting member 31 in the fixed sleeve 3, since the fixed sleeve 3 is fixed and motionless, the third rotating member 2 is stopped at the current position, the steering shaft 1 stops rotating, and the steering wheel can no longer rotate. When the steering wheel is rotated in the reverse direction, similarly, when the second limiting portion 21 of the third rotating member 2 contacts another limiting member 31 in the fixed sleeve 3, the steering wheel can no longer rotate, thereby achieving the rotation angle limitation of the steering shaft 1.

[0064] This embodiment also provides a wire-controlled steering system, including a steering wheel and a limit device as described above, wherein the steering wheel is connected to the steering shaft 1 of the limit device. In the wire-controlled steering system using the limit device, when the steering wheel drives the steering shaft 1 to rotate, the rotating member 2 and the two limit members 31 cooperate to limit the rotation angle range of the steering shaft 1, and can generate a rotation resistance torque on the steering wheel under the electrical condition of the electronic control system of the wire-controlled steering system or when a fault occurs, so as to limit the number of rotations of the steering wheel and protect the clock spring.

[0065] This embodiment also provides a vehicle, including the above-mentioned steer-by-wire system, which is in driving connection with the wheels of the vehicle. The vehicle using the steer-by-wire system can generate a rotational resistance torque on the steering wheel when the electronic control system of the steer-by-wire system is in an off-state condition or when a fault occurs, so as to limit the number of rotations of the steering wheel, protect the clock spring, and improve the driving safety of the vehicle.

[0066] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A limit device, characterized in that: include: A steering shaft (1), wherein the steering shaft (1) is provided with a first limiting portion (41); At least one rotating member (2) is rotatably sleeved on the steering shaft (1) in sequence along the axial direction of the steering shaft (1); the rotating member (2) is provided with a second limiting portion (21); the second limiting portion (21) on the rotating member (2) located at the first axial end of the steering shaft (1) can abut against or separate from the first limiting portion (41) along the circumferential direction of the steering shaft (1); and the second limiting portions (21) on any two adjacent rotating members (2) can abut against or separate from each other along the circumferential direction of the steering shaft (1); Two rotation limiting members (31) are arranged at intervals along the circumferential direction of the steering shaft (1) and are used to limit the rotation range of the second limiting portion (21) on the rotating member (2) located at the second axial end of the steering shaft (1).

2. The limiting device according to claim 1, characterized in that: The limiting device further comprises a fixed sleeve (3), wherein the fixed sleeve (3) is sleeved on the steering shaft (1) and at least one of the rotating members (2) at intervals, and the two rotating limiting members (31) are arranged on the inner circumference of the fixed sleeve (3).

3. The limiting device according to claim 1, characterized in that: The limiting device also includes a fixing ring (4) sleeved on the steering shaft (1), and the first limiting portion (41) is arranged on the fixing ring (4).

4. The limiting device according to claim 3, characterized in that: The steering shaft (1) is provided with a first limiting structure, and the fixing ring (4) is provided with a second limiting structure, and the first limiting structure and the second limiting structure cooperate to limit the rotation of the fixing ring (4) relative to the steering shaft (1).

5. The limiting device according to claim 4, characterized in that: The first limiting structure comprises a first limiting surface (121) arranged on the outer peripheral wall of the steering shaft (1), and the second limiting structure comprises a second limiting surface (42) arranged on the inner peripheral wall of the fixing ring (4), and the first limiting surface (121) is in contact with the second limiting surface (42).

6. The limiting device according to claim 3, characterized in that: The steering shaft (1) is provided with a first shaft shoulder (14), and the fixing ring (4) is axially limited on the steering shaft (1) by the first shaft shoulder (14).

7. The limiting device according to any one of claims 1 to 6, characterized in that: The steering shaft (1) is provided with a second shaft shoulder (15), and the limiting device further comprises a retaining ring (6), wherein the retaining ring (6) is clamped on the steering shaft (1) and spaced apart from the second shaft shoulder (15), and at least one of the rotating parts (2) is axially limited on the steering shaft (1) by the second shaft shoulder (15) and the retaining ring (6).

8. The limiting device according to any one of claims 1 to 6, characterized in that: The rotating member (2) is rotatably mounted on the steering shaft (1) via a bearing (5); Alternatively, the outer circumferential surface of the steering shaft (1) and / or the inner circumferential surface of the rotating member (2) are provided with a lubricating layer.

9. The limiting device according to any one of claims 1 to 6, characterized in that: The first position limiting portion (41), the second position limiting portion (21) and / or the rotation limiting member (31) are provided with buffer layers on both sides along the circumferential direction of the steering shaft (1).

10. A steer-by-wire system, characterized in that: It comprises a steering wheel and a limiting device as claimed in any one of claims 1 to 9, wherein the steering wheel is connected to a steering shaft (1) of the limiting device.

11. A vehicle, characterized in that Comprising the steer-by-wire system of claim 10, the steer-by-wire system being drivingly connected to the wheels of the vehicle.

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