Rear wheel steering gear and vehicle

Abstract

The invention provides a rear wheel steering gear and a vehicle. The rear wheel steering gear comprises a clutch, a transmission shaft and a tie rod. The clutch is in transmission connection with the steering motor and the transmission shaft; and the transmission shaft is used for driving the tie rod to displace and further driving the two rear wheels to steer. The clutch includes an input member, an output member, and two meniscus plates. One end of the input piece is in transmission connection with a steering motor, and the other end comprises a pair of axial protrusions. The pair of axial protrusions are arranged at intervals in the radial direction of the clutch, and each axial protrusion is used for being in transmission connection with a meniscus. One end of the output piece comprises another pair of axial protrusions, and the other end is used for being in transmission connection with a transmission shaft. The arrangement direction of the other pair of axial protrusions is perpendicular to the arrangement direction of the pair of axial protrusions. The two half-moon plates are arranged at intervals in the arrangement direction of one pair of axial protrusions, and a gap between the two half-moon plates is used for containing the other pair of axial protrusions. By optimizing the internal structure of the rear wheel steering gear, the torque bearing capacity of the rear wheel steering gear is increased to improve the reliability.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a rear wheel steering gear and a vehicle. Background Art

[0002] The rear wheel steering gear is used to control the rear wheel steering of the vehicle to reduce the vehicle's center of mass side slip angle during the steering process, reduce the steady-state overshoot of the vehicle's yaw rate, and achieve smooth steering. Before and after the vehicle turns, the rear wheel steering gear needs to be used to limit the rear wheel steering to ensure normal driving of the vehicle. Summary of the invention

[0003] The present application provides a rear wheel steering gear and a vehicle. By optimizing the internal structure of the rear wheel steering gear, the torque bearing capacity of the rear wheel steering gear is increased to improve reliability.

[0004] In a first aspect, the present application provides a rear wheel steering device. The rear wheel steering device includes a clutch, a transmission shaft and a tie rod, a clutch is used to drive a steering motor and a transmission shaft, a transmission shaft is used to drive a tie rod to move along the axial direction of a tie rod, a tie rod is used to drive two rear wheels to steer, and a clutch includes an input member, an output member and two menisci.

[0005] One end of one of the input members is used for transmission connection with a steering motor, and the other end of the input member includes a pair of axial protrusions, the pair of axial protrusions are arranged at intervals along the radial direction of a clutch, and each axial protrusion of the pair of axial protrusions is used for transmission connection with a meniscus. One end of one of the output members includes another pair of axial protrusions, the other end of the output member is used for transmission connection with a transmission shaft, the other pair of axial protrusions are arranged at intervals along the radial direction of a clutch, and the arrangement direction of the other pair of axial protrusions is perpendicular to the arrangement direction of the pair of axial protrusions. Two menisci are arranged at intervals along the arrangement direction of the pair of axial protrusions, and the gap between the two menisci is used to accommodate the other pair of axial protrusions.

[0006] The rear wheel steering device provided by the present application outputs driving force through a steering motor, and a clutch and a transmission shaft are used to transmit the driving force to a tie rod to drive the tie rod to move axially, thereby driving the two rear wheels to steer. One of the clutches is connected to the motor shaft of a steering motor through an input member, connected to a transmission shaft through an output member, and connected to an input member and an output member through two meniscus plates.

[0007] An input member and an output member in the rear wheel steering device provided by the present application respectively include a pair of axial protrusions. A pair of axial protrusions of an input member are matched with another pair of axial protrusions of an output member through two menisci. Two axial protrusions in each pair of axial protrusions are arranged at intervals, and the arrangement directions of the two pairs of axial protrusions are perpendicular to each other. A pair of axial protrusions of an input member are arranged at intervals along the arrangement direction of the two menisci.

[0008] Thus, two axial protrusions of the two pairs of axial protrusions are arranged alternately along the circumference of a clutch, and the other pair of axial protrusions of an output member and the two menisci are arranged alternately along the circumference of a clutch. The meshing points of an input member and an output member with the two menisci are respectively away from the axis of a clutch, and the force radius between an input member and the two menisci, and the force radius between an output member and the two menisci are larger, and the contact stress is smaller, thereby increasing the torque bearing capacity of the rear wheel steering device provided by the present application and improving the reliability.

[0009] In one implementation, a pair of axial protrusions of an input member are symmetrically arranged along the radial direction of a clutch.

[0010] In one implementation, another pair of axial protrusions of an output member are symmetrically arranged along the radial direction of a clutch.

[0011] In the above two implementations, when an input member or an output member rotates circumferentially around a clutch, the radius of action between a pair of axial protrusions or another pair of axial protrusions and the two menisci are equal, and the circumferential forces on the two menisci along a clutch are relatively balanced, thereby increasing the torque bearing capacity of the two menisci and improving reliability.

[0012] In one implementation, a clutch housing is used to accommodate two menisci, the arc surface of each meniscus faces the inner wall of the housing along the arrangement direction of a pair of axial protrusions, and the inner wall of the housing is used to abut the arc surface of each meniscus.

[0013] In this implementation, a clutch housing forms friction by abutting against the arcuate surfaces of two menisci, thereby limiting the circumferential rotation of the two menisci. Another pair of axial protrusions accommodated in the gap between the two menisci are also limited to circumferential rotation along a clutch. The rear wheel steering gear provided by the present application also limits the rotation of a transmission shaft through a clutch, thereby achieving the effect of limiting the axial displacement of a tie rod by a clutch.

[0014] Therefore, when the vehicle is traveling on an uneven road surface and the two rear wheels make unexpected turns, the rear wheel steering device of the present application can limit the axial displacement of a tie rod through a clutch to limit the angle of the unexpected turns of the two rear wheels, ensure the smooth driving of the vehicle and reduce the frequency of intervention of a steering motor to limit the unexpected turns of the two rear wheels. The power consumption of the rear wheel steering device of the present application is lower, and the service life of the steering motor is longer.

[0015] In one implementation, each axial protrusion in a pair of axial protrusions includes two cylindrical embedded parts, each meniscus includes two trapezoidal through holes, each trapezoidal through hole is used to accommodate an embedded part, and the long side, short side, oblique side and bottom side of each trapezoidal through hole are respectively connected by an arc segment.

[0016] In this implementation, each axial protrusion in a pair of axial protrusions is connected to a meniscus through two cylindrical embedded parts. Each embedded part is used to embed a trapezoidal through hole and drive a meniscus to rotate by abutting against the hole wall of a trapezoidal through hole. An arc segment is used to connect the hole walls of each side of a trapezoidal through hole to reduce the stress concentration in a trapezoidal through hole.

[0017] In one implementation, the long sides of the two trapezoidal through holes are arranged between the short sides of the two trapezoidal through holes, the two trapezoidal through holes are symmetrically arranged along the radial axis of a clutch, and the spacing between the hypotenuse and the base in each trapezoidal through hole is greater than the outer diameter of each embedded portion.

[0018] In this implementation, the two trapezoidal through holes are arranged symmetrically along the long and short sides relative to the radial axis of a clutch, and the distance between the two long sides is closer. Thus, the oblique sides and the bottom sides of the two trapezoidal through holes are arranged along the arrangement direction of a pair of axial protrusions. Each embedded portion is used to move between the oblique side and the bottom side of a trapezoidal through hole to drive the two menisci to move relative to each other, and make the two menisci spaced from the inner wall of the housing of a clutch during the rotation process with the pair of axial protrusions.

[0019] In one implementation, the distance between the two embedded portions along the circumferential direction of a clutch is smaller than the distance between the long side and the short side of each trapezoidal through hole.

[0020] In this implementation, the distance between the two embedded parts is smaller, and when an input member rotates clockwise or counterclockwise, there is always an embedded part abutting against the long side of a trapezoidal through hole to drive a meniscus. The force radius of a meniscus is larger and the torque bearing effect is better.

[0021] In one implementation, each meniscus includes an axial through hole, an axial through hole is used to accommodate one axial protrusion of a pair of axial protrusions, an axial through hole is symmetrical along a radial axis of a clutch, and the aperture of the axial through hole decreases in a clockwise direction and a counterclockwise direction from the symmetry axis of the axial through hole.

[0022] In this implementation, each axial protrusion in a pair of axial protrusions is connected to a meniscus by being embedded in an axial through hole. An axial through hole is symmetrical along the radial axis of a clutch. Along the circumferential direction of a clutch, the apertures at both ends of an axial through hole are smaller than the aperture in the middle section of an axial through hole. When rotating, one of the axial protrusions in a pair of axial protrusions first abuts against the radial hole wall of an axial through hole to drive a meniscus to move along the arrangement direction of the pair of axial protrusions, and space a meniscus from the inner wall of a clutch housing. One of the axial protrusions in a pair of axial protrusions then abuts against the circumferential hole wall on one side of an axial through hole to drive a meniscus to rotate.

[0023] In one implementation, the gap between the two menisci is used to install at least one elastic member, and each elastic member is used to abut a meniscus at both ends along the arrangement direction of a pair of axial protrusions, and at least one elastic member is used to push the arc surface of each meniscus to move along the arrangement direction of the pair of axial protrusions toward the inner wall of a clutch housing.

[0024] In this implementation, each elastic member is used to push two menisci along the arrangement direction of a pair of axial protrusions to respectively abut against the inner wall of a clutch housing, so as to keep the two menisci against the inner wall of a clutch housing and form friction before an input member rotates. Thus, before a steering motor rotates, a clutch can be used to keep the rotation of an output member restricted.

[0025] In one implementation, the material of each elastic member is a viscoelastic damping material to reduce the knocking noise generated when the two menisci are relatively close to each other.

[0026] In one implementation, the material of each elastic member is rubber or polyurethane sponge.

[0027] In one implementation, each elastic member is located between another pair of axial protrusions along the arrangement direction of the other pair of axial protrusions. This can make the structure of a clutch more compact while ensuring that the force radius of the other pair of axial protrusions is larger, thereby reducing the overall volume of the rear wheel steering gear provided in the present application.

[0028] In one implementation, the side of each meniscus facing the other meniscus includes a protrusion and a groove, and a groove of one of the two menisci is used to accommodate a protrusion of the other meniscus.

[0029] In this implementation, a protrusion and a groove extend along the arrangement direction of a pair of axial protrusions, thereby forming a guiding function when the two menisci are relatively displaced. Two pairs of mutually matching protrusions and a groove are arranged alternately, which can increase the guiding length of the two menisci along the arrangement direction of the pair of axial protrusions, thereby preventing the two protrusions from falling off from the two grooves respectively.

[0030] In one implementation, at least one of the two surfaces of a protrusion and a groove that match each other includes a coating layer, which is a phosphating layer or a molybdenum disulfide layer to reduce the wear between the protrusion and the groove.

[0031] In one implementation method, along the arrangement direction of another pair of axial protrusions, a protrusion and a groove on a meniscus are both located between the other pair of axial protrusions. This can make the structure of a clutch more compact while ensuring that the force radius of the other pair of axial protrusions is larger, thereby reducing the overall volume of the rear wheel steering gear provided in the present application.

[0032] In one implementation, one end of each elastic member is used to fix a protrusion of one meniscus, and the other end of each elastic member is used to fix a groove bottom of a groove of another meniscus.

[0033] In this implementation, an elastic member is installed by utilizing the space between the bottom of a protrusion and a groove, thereby ensuring the fit of a protrusion and a groove, as well as the function of an elastic member, respectively, making the structure of a clutch more compact and reducing the overall volume of the rear wheel steering gear provided in this application.

[0034] In one implementation, each meniscus includes two receiving grooves, the groove of each receiving groove in each meniscus faces the other meniscus, one receiving groove of each meniscus cooperates with one receiving groove of the other meniscus to accommodate one axial protrusion of the other pair of axial protrusions, and the other receiving groove of each meniscus cooperates with the other receiving groove of the other meniscus to accommodate the other axial protrusion of the other pair of axial protrusions.

[0035] In this implementation, each meniscus accommodates the partial structures of the two axial protrusions in the other pair of axial protrusions through two accommodating grooves, that is, the two axial protrusions in the other pair of axial protrusions are respectively embedded in the two accommodating grooves of one meniscus. This widens the circumferential dimensions of the two axial protrusions in the other pair of axial protrusions, increases the torque bearing capacity of the other pair of axial protrusions, and improves reliability.

[0036] In one implementation, the slot width of each receiving slot is smaller than the slot bottom width, each receiving slot includes a first slot wall and a second slot wall, and the axial distance between a first slot wall and a clutch in each receiving slot is smaller than the axial distance between a second slot wall and a clutch. The curvature of a first slot wall in each receiving slot is greater than the curvature of a second slot wall, the bending direction of a first slot wall in each receiving slot is away from a second slot wall, the bending directions of the first slot walls of the two receiving slots in each meniscus are opposite, and the bending directions of the first slot walls of the two matching receiving slots in the two menisci are the same.

[0037] In this implementation, the first groove wall of each accommodating groove on the side close to the axis of one clutch is formed as an arc-shaped groove wall. The center of the arc-shaped groove wall is close to the axis of one clutch. The first groove wall can form a guiding function for one axial protrusion of the other pair of axial protrusions, guiding the other pair of axial protrusions to rotate around the axis of one clutch.

[0038] In one implementation, each axial protrusion in the other pair of axial protrusions is bent toward the other axial protrusion. The dimension of each axial protrusion in the other pair of axial protrusions along the circumferential direction of one clutch is greater than the dimension along the radial direction of one clutch. The curvature of each axial protrusion in the other pair of axial protrusions is greater than or equal to the curvature of the first groove wall of each meniscus.

[0039] In this implementation, each axial protrusion in the other pair of axial protrusions is arc-shaped, and the arc-shaped axial protrusion can fit with the two accommodating grooves to enhance the guiding effect between the first groove wall and the second axial protrusion.

[0040] In one implementation, each meniscus includes an arcuate surface and a plane, the two arcuate surfaces of the two meniscus face opposite to each other, and each arcuate surface is used to face the inner wall of a clutch housing along the arrangement direction of a pair of axial protrusions. The two planes of the two meniscus face opposite to each other, and the spacing between the two planes is greater than the circumferential width of the other pair of axial protrusions.

[0041] In one implementation, a protrusion, a groove and two receiving grooves of a meniscus are all located on a plane.

[0042] In one implementation, a clutch housing includes an input housing and an output housing, wherein the output housing and the output housing are arranged adjacent to each other along the axial direction of the clutch, and the output housing is used to enclose an input housing. One of the input housings is used to fix the outer ring of a bearing, and the inner ring of a bearing is used to fix one end of an input member. One of the output housings is used to fix the outer ring of another bearing, and the inner ring of another bearing is used to fix the other end of an output member.

[0043] In this implementation, a clutch housing is further used to accommodate two bearings, each bearing being used to support an input member or an output member to ensure that an input member and an output member rotate smoothly around an axis of a clutch.

[0044] In one implementation, one end of an input member includes an internal spline, and a distance between a pair of axial protrusions in the other end of an input member is greater than an outer diameter of one end of the input member.

[0045] In this implementation, one end of an input member is connected to a motor shaft of a steering motor through an internal spline transmission. The spacing between a pair of axial protrusions at the other end of an input member is relatively large to increase the radius of force between an input member and two menisci.

[0046] In one implementation, the other end of an output member includes another internal spline, and the spacing between another pair of axial protrusions in one end of an output member is greater than the outer diameter of the other end of the output member.

[0047] In this implementation, the other end of an output member is connected to a transmission shaft through another internal spline transmission. The spacing between the other pair of axial protrusions at one end of an output member is relatively large to increase the radius of force between an output member and two menisci.

[0048] In one implementation, an input side housing is used to accommodate two menisci and an input member. One of the output side housings includes a mounting surface, and the mounting surface includes a plurality of bolt holes, each of which is used to pass a bolt. An input side housing includes another mounting surface, and the other mounting surface is used to fix an output side housing, and the other mounting surface includes a plurality of bolt slots, each of which is used to fix and accommodate a bolt passing through a bolt hole.

[0049] In this implementation, a clutch accommodates two menisci and an input member through an input side housing. Because an input side housing is close to a steering motor, and a steering motor is fixed to the vehicle frame. The structural stability of an input side housing is better than that of an output side housing, and an input side housing facilitates better support and abutment of two menisci.

[0050] In one implementation, the inner wall of an input-side housing or the arcuate surface of each meniscus includes a plurality of radial grooves, and the plurality of radial grooves are arranged at intervals along the circumference of a clutch.

[0051] In this implementation, multiple radial grooves can increase the friction between each meniscus and the inner wall of an input side shell, and are used to store powder from the wear of each meniscus and the inner wall of an input side shell, reducing the impact of the wear powder on the friction between each meniscus and the inner wall of an input side shell.

[0052] In one implementation, an arcuate surface and a plane of each meniscus are connected by an arc segment, so as to prevent interference between the two ends of the two menisci along the arrangement direction of the other pair of axial protrusions and the plurality of radial grooves during rotation.

[0053] In one implementation, an input member includes a positioning plate, and the size of the positioning plate along the arrangement direction of a pair of axial protrusions is greater than the size along the arrangement direction of another pair of axial protrusions. Along the axial direction of a clutch, a positioning plate includes a first plate surface and a second plate surface facing each other, the first plate surface is used to fix a transmission column, and the second plate surface is used to fix a pair of axial protrusions, and a transmission column is used to drive and connect the motor shaft of a steering motor.

[0054] In one implementation, an output member includes another positioning plate, and the dimension of the other positioning plate along the arrangement direction of a pair of axial protrusions is smaller than the dimension along the arrangement direction of another pair of axial protrusions. Along the axial direction of a clutch, the other positioning plate includes a third plate surface and a fourth plate surface facing each other, the third plate surface is used to fix another pair of axial protrusions, and the fourth plate surface is used to fix another transmission column, and the other transmission column is used to drive and connect a transmission shaft.

[0055] In one implementation, the axis of a transmission shaft is parallel to the axis of a tie rod, a transmission shaft is spaced from a tie rod along the radial direction of a clutch, and an end of a transmission shaft away from a steering motor along the axial direction of a clutch is used to drive and connect the middle section of a tie rod through a transmission member. During the rotation of one of the steering motors, a transmission shaft is used to drive a tie rod to move axially along the tie rod through a transmission member. Before a steering motor rotates, a clutch is used to limit the axial movement of a tie rod along the tie rod by limiting the rotation of a transmission member driven by a transmission shaft.

[0056] In this implementation, a transmission shaft is parallel to the axis of a tie rod, which can reduce the radial size of the rear wheel steering gear provided by the present application along a clutch and compress the volume of a transmission component, thereby facilitating the arrangement and assembly of the rear wheel steering gear.

[0057] In one implementation, a transmission member includes a transmission wheel and a screw sleeve, wherein the transmission wheel is used to be fixed to an end of a transmission shaft away from a steering motor along the axial direction of a clutch. The inner circumference of a screw sleeve is used to mesh with the outer circumference of a middle section of a tie rod. The transmission wheel is used to drive and connect the outer circumference of a screw sleeve along the radial direction of a clutch, and the diameter of the transmission wheel is smaller than the diameter of a screw sleeve.

[0058] In this implementation, the diameter of a transmission wheel is smaller than the diameter of a screw sleeve, and a transmission member forms a deceleration effect from a transmission shaft toward a screw sleeve. During the rotation of a steering motor, a transmission member is used to reduce the rotation speed of a screw sleeve and amplify the driving force output by a steering motor. When the two rear wheels make an unexpected turn, a transmission member is used to reduce the reverse driving force of a tie rod acting on a transmission shaft, so that a clutch can limit the rotation of a transmission shaft.

[0059] In one implementation, a transmission member includes a transmission belt, and an inner surface of the transmission belt is used to engage with an outer peripheral surface of a transmission wheel and an outer peripheral surface of a screw sleeve respectively.

[0060] In one implementation, a transmission member includes a tensioning wheel, and the tensioning wheel is used to squeeze a transmission belt to increase the tension between a transmission belt, a transmission wheel and a threaded sleeve.

[0061] In one implementation, a tie rod includes a threaded section in the middle section along the axial direction, an inner circumferential surface of a screw sleeve is used to mesh with a threaded section, and a screw sleeve is used to rotate around the axis of a tie rod along with a transmission wheel, while driving a tie rod to move axially.

[0062] In one implementation, a plurality of balls are included between the inner circumference of a screw sleeve and a threaded section. The plurality of balls are used to reduce the friction between a screw sleeve and a tie rod, thereby improving the transmission efficiency of the rear wheel steering gear provided by the present application.

[0063] In this implementation, because the rear-wheel steering device of the present application limits the axial displacement of a tie rod through a clutch, a transmission member that limits the axial displacement of a tie rod through internal friction to reduce the intervention frequency of the steering motor is eliminated. Therefore, the transmission efficiency of a transmission member can be improved to reduce the power consumption of a steering motor during rotation.

[0064] In a second aspect, the present application provides a vehicle, the vehicle comprising two rear wheels and a rear wheel steering device provided by any of the above implementations. The rear wheel steering device is used to drive the two rear wheels to change the direction. The vehicle of the present application has increased load-bearing capacity on the basis of having a rear wheel steering function, and has higher reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0066] Figure 1A schematic diagram of the appearance structure of a vehicle provided in one embodiment of the present application;

[0067] Figure 2 A schematic diagram of the structure of a rear wheel steering device and a rear wheel provided in an embodiment of the present application;

[0068] Figure 3 A schematic diagram of the structure of a rear wheel steering device provided in one embodiment of the present application;

[0069] Figure 4 A schematic cross-sectional structure diagram of a rear wheel steering gear provided by an embodiment of the present application;

[0070] Figure 5 for Figure 4 The cross-sectional structure diagram of the transmission mechanism at A in the middle;

[0071] Figure 6 A schematic diagram of the structure of a transmission component in a rear wheel steering device provided in an embodiment of the present application;

[0072] Figure 7 A schematic cross-sectional structure diagram of a transmission component in a rear wheel steering device provided in an embodiment of the present application;

[0073] Figure 8 A partial structural schematic diagram of a rear wheel steering device provided by an embodiment of the present application;

[0074] Fig. 9 A schematic diagram of the structure of a clutch of a rear wheel steering device provided in one embodiment of the present application;

[0075] Fig.10 A schematic diagram of the exploded structure of a clutch of a rear wheel steering device provided in one embodiment of the present application;

[0076] Fig.11 A schematic cross-sectional structure diagram of a clutch of a rear wheel steering device provided in one embodiment of the present application;

[0077] Fig.12 A schematic cross-sectional structure diagram of a clutch of a rear wheel steering device provided in an embodiment of the present application from another viewing angle;

[0078] Fig.13 A schematic structural diagram of a meniscus in a rear wheel steering device provided in an embodiment of the present application;

[0079] Fig.14 A schematic diagram of a structure in which two menisci are arranged in a clutch housing in a rear wheel steering device provided by an embodiment of the present application;

[0080] Fig.15 A schematic structural diagram of a rear wheel steering device in an initial state provided by an embodiment of the present application;

[0081] Fig.16 A schematic diagram of a structure in which an input member in a rear wheel steering device provided by an embodiment of the present application drives two menisci and an output member to rotate;

[0082] Fig.17 A schematic diagram of a structure in which two menisci restrict the rotation of an output member in a rear wheel steering device provided in an embodiment of the present application;

[0083] Fig.18 A schematic diagram of the exploded structure of a housing in a rear wheel steering gear provided in one embodiment of the present application;

[0084] Fig.19 A schematic diagram of the structure of two menisci cooperating with a shell in a rear wheel steering device provided by an embodiment of the present application;

[0085] Fig. 20 A schematic diagram of the structure of an input component of a rear wheel steering device provided by an embodiment of the present application;

[0086] Fig.21 A schematic diagram of the structure of an output member of a rear wheel steering device provided in one embodiment of the present application;

[0087] Fig. 22 A schematic diagram of the structure of the input member of a rear wheel steering device provided by an embodiment of the present application cooperating with a meniscus;

[0088] Fig.23 A schematic diagram of the exploded structure of the input member of a rear wheel steering device provided by an embodiment of the present application cooperating with a meniscus;

[0089] Fig.24 A schematic diagram of a planar structure of the input member of a rear wheel steering device provided by an embodiment of the present application cooperating with two menisci;

[0090] Fig.25 A schematic diagram of a planar structure of an input member of a rear wheel steering device provided by an embodiment of the present application and two menisci cooperating in rotation;

[0091] Fig.26 A schematic diagram of the partial structure of two trapezoidal through holes of a meniscus of a rear wheel steering device provided in one embodiment of the present application;

[0092] Fig. 27 A schematic diagram of a planar structure of an axial through hole and a first axial protrusion of a meniscus of a rear wheel steering device provided in an embodiment of the present application;

[0093] Fig.28 A schematic diagram of the planar structure of the cooperation between two menisci and an elastic member of a rear wheel steering device provided in one embodiment of the present application;

[0094] Fig.29 A schematic diagram of the planar structure of two menisci cooperating with each other in a rear wheel steering device provided in one embodiment of the present application;

[0095] Fig.30 A schematic diagram of the exploded structure of two menisci cooperating with each other in a rear wheel steering device provided in one embodiment of the present application;

[0096] Fig.31 A schematic diagram of the structure of the output member of the rear wheel steering device provided by an embodiment of the present application cooperating with two menisci;

[0097] Fig.32 A schematic diagram of the exploded structure of the output member of the rear wheel steering device provided by one embodiment of the present application cooperating with two menisci;

[0098] Fig.33 A schematic diagram of a planar structure of an output member of a rear wheel steering device provided by an embodiment of the present application cooperating with two menisci;

[0099] Fig.34 A schematic structural diagram of a meniscus in a rear wheel steering gear provided in one embodiment of the present application. DETAILED DESCRIPTION

[0100] The following will describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0101] The present application provides a rear wheel steering device. The rear wheel steering device includes a clutch, a transmission shaft and a tie rod, a clutch is used to drive a steering motor and a transmission shaft, a transmission shaft is used to drive a tie rod to move along the axial direction of a tie rod, a tie rod is used to drive two rear wheels to steer, and a clutch includes an input member, an output member and two menisci.

[0102] One end of one of the input members is used for transmission connection with a steering motor, and the other end of the input member includes a pair of axial protrusions, the pair of axial protrusions are arranged at intervals along the radial direction of a clutch, and each axial protrusion of the pair of axial protrusions is used for transmission connection with a meniscus. One end of one of the output members includes another pair of axial protrusions, the other end of the output member is used for transmission connection with a transmission shaft, the other pair of axial protrusions are arranged at intervals along the radial direction of a clutch, and the arrangement direction of the other pair of axial protrusions is perpendicular to the arrangement direction of the pair of axial protrusions. Two menisci are arranged at intervals along the arrangement direction of the pair of axial protrusions, and the gap between the two menisci is used to accommodate the other pair of axial protrusions.

[0103] The arrangement directions of the two pairs of axial protrusions in the rear wheel steering device provided by the present application are perpendicular to each other. The meshing points of an input member and an output member with the two menisci are respectively far away from the axis of a clutch, and the force radius between an input member and the two menisci, and the force radius between an output member and the two menisci are larger, and the contact stress is smaller, thereby increasing the torque bearing capacity of the rear wheel steering device provided by the present application and improving the reliability.

[0104] The present application provides a vehicle, which includes two rear wheels and the rear wheel steering device provided above. The rear wheel steering device is used to drive the two rear wheels to change the direction. The vehicle of the present application has increased load-bearing capacity on the basis of having the rear wheel steering function, and has higher reliability.

[0105] See also Figure 1 A schematic diagram of the appearance structure of a vehicle 1000 provided in one embodiment of the present application is shown.

[0106] like Figure 1 As shown, the vehicle 1000 provided by the present application includes a frame 1001, two rear wheels 1002, two front wheels 1003 and a rear wheel steering gear 200. The frame 1001 is used to rotatably connect the two rear wheels 1002 and the two front wheels 1003. The rear wheel steering gear 200 is used to be fixed to the frame 1001 and is in driving connection with the two rear wheels 1002 of the vehicle 1000. The rear wheel steering gear 200 is used to drive the two rear wheels 1002 of the vehicle 1000 to change the steering direction, thereby expanding the control range of the steering angle of the vehicle 1000 and reducing the phenomenon of understeering or oversteering of the vehicle 1000.

[0107] For example, in some scenarios, when the vehicle 1000 needs to turn or make a U-turn with a smaller turning radius, the front wheels 1003 and the rear wheels 1002 of the vehicle 1000 can be controlled to rotate in opposite directions, thereby reducing the turning radius and improving the flexibility of the vehicle 1000. In other scenarios, when the vehicle 1000 needs to turn at a certain speed, the front wheels 1003 and the rear wheels 1002 of the vehicle 1000 can be controlled to rotate in the same direction, thereby reducing the center of mass side slip angle of the vehicle 1000, reducing the steady-state overshoot of the yaw rate of the vehicle 1000, and thus enhancing the handling stability of the vehicle 1000.

[0108] Please see Figure 2 and Figure 3 , Figure 2 A schematic diagram of the structure of a rear wheel steering device 200 and a rear wheel 1002 provided in an embodiment of the present application; Figure 3 A schematic structural diagram of a rear wheel steering device 200 provided in one embodiment of the present application.

[0109] like Figure 2 and Figure 3 As shown, the rear wheel steering device 200 provided by the present application includes a steering motor 10, a transmission mechanism 20 and a tie rod 30, wherein the steering motor 10 is used to drive the tie rod 30 to move through the transmission mechanism 20 to drive the two rear wheels 1002 to steer. The steering motor 10 is fixed to the frame 1001, and the motor shaft 11 of the steering motor 10 is parallel to the axial direction of the rear wheel 1002. The tie rod 30 is slidably connected to the frame 1001 along the axial direction parallel to the rear wheel 1002, and the tie rod 30 extends along the axial direction parallel to the rear wheel 1002. At least one axial end of the tie rod 30 is used to be connected to a rear wheel 1002 through a steering knuckle 1004. The transmission mechanism 20 is used to transmit and connect the steering motor 10 and the tie rod 30. The transmission mechanism 20 includes an input end 21 and an output end 22. The input end 21 is used to receive the driving force of the steering motor 10, and the output end 22 is used to drive the tie rod 30 to move along its own axial direction to drive the rear wheel 1002 to deflect relative to the frame 1001 to achieve steering of the rear wheel 1002.

[0110] In the illustrated embodiment, the tie rod 30 is connected to a rear wheel 1002 at both ends along the axial direction through a steering knuckle 1004. The transmission mechanism 20 is used to receive the driving force of the steering motor 10 to drive the tie rod 30 to move axially, and the tie rod 30 is used to drive the two rear wheels 1002 to steer.

[0111] In one embodiment, the output end 22 includes a transmission member 221, which is in transmission connection with the tie rod 30. The transmission member 221 receives the driving force of the input end 21 and transmits it to the tie rod 30 to drive the tie rod 30 to move along its own axial direction.

[0112] In one embodiment, the transmission member 221 includes a threaded sleeve 2211 , which is sleeved on the outer circumference of the tie rod 30 , and the inner circumference of the threaded sleeve 2211 is meshed with the outer circumference of the tie rod 30 .

[0113] For details, please refer to Figure 4 and Figure 5 ,in Figure 4 A schematic cross-sectional structure diagram of a rear wheel steering device 200 provided in one embodiment of the present application; Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure of the transmission mechanism 20.

[0114] like Figure 4 and Figure 5 As shown, the tie rod 30 includes a threaded section 31, a screw sleeve 2211 is sleeved on the threaded section 31, and the internal thread of the inner circumferential surface of the screw sleeve 2211 is correspondingly meshed with the thread of the threaded section 31. The screw sleeve 2211 receives the driving force of the input end 21, rotates relative to the tie rod 30 around the axis of the tie rod 30 and drives the tie rod 30 to move along its own axial direction, so that the rear wheel 1002 can achieve steering. It can be understood that the screw sleeve 2211 cooperates with the threaded section 31 of the tie rod 30 to ensure the reliability of the transmission member 221 driving the tie rod 30 to move along its own axial direction.

[0115] In one embodiment, a plurality of balls 32 are disposed between the inner circumference of the screw sleeve 2211 and the threaded section 31 of the tie rod 30. The plurality of balls 32 are arranged at intervals along the circumference of the tie rod 30 and are held between the inner circumference of the screw sleeve 2211 and the outer circumference of the threaded section 31. It can be understood that the plurality of balls 32 can reduce the friction between the screw sleeve 2211 and the tie rod 30, thereby improving the transmission efficiency of the rear wheel steering device 200 of the present application.

[0116] In one embodiment, the input end 21 includes a transmission shaft 211, the axis of the transmission shaft 211 is parallel to the axis of the tie rod 30, and the transmission shaft 211 and the tie rod 30 are arranged at intervals along the radial direction of the transmission shaft 211. Along the axial direction of the transmission shaft 211, the opposite ends of the transmission shaft 211 are respectively connected to the steering motor 10 and the transmission member 221.

[0117] Specifically, the transmission member 221 includes a transmission wheel 2212, which is sleeved on the end of the transmission shaft 211 away from the steering motor 10 along its own axial direction and fixed to the transmission shaft 211. Along the radial direction of the transmission shaft 211, the transmission wheel 2212 is used to transmit and connect the outer peripheral surface of the screw sleeve 2211. Therefore, the rotation of the motor shaft 11 of the steering motor 10 can drive the transmission shaft 211 to rotate, and the transmission wheel 2212 rotates with the transmission shaft 211 and drives the screw sleeve 2211 to rotate, so that the tie rod 30 can be displaced along its own axial direction.

[0118] It can be understood that setting the axis of the transmission shaft 211 parallel to the axis of the transverse tie rod 30 can reduce the radial size of the rear wheel steering gear 200 provided in the present application along the transmission shaft 211 and compress the volume of a transmission member 221, thereby facilitating the arrangement and assembly of the rear wheel steering gear 200.

[0119] In one embodiment, the transmission method between the transmission wheel 2212 and the screw sleeve 2211 may include any one or more combinations of belt transmission, chain transmission, gear transmission, gear rack transmission, etc., to ensure that the driving force of the transmission wheel 2212 can be reliably transmitted to the screw sleeve 2211, and enable the screw sleeve 2211 to rotate around the axis of the transverse rod 30 to drive the transverse rod 30 to move along its own axial direction. This application does not make any special limitations on this.

[0120] For ease of description, the subsequent embodiments of the present application will be described using a belt drive between the transmission wheel 2212 and the screw sleeve 2211 as an example.

[0121] Please see Figure 6 and Figure 7 ,in Figure 6 A schematic diagram of the structure of a transmission member 221 in a rear wheel steering device 200 provided in an embodiment of the present application; Figure 7 A schematic cross-sectional structure diagram of a transmission member 221 in a rear wheel steering gear 200 provided in an embodiment of the present application.

[0122] like Figure 6 and Figure 7 As shown, the transmission member 221 includes a transmission belt 2213, and the inner surface of the transmission belt 2213 is respectively meshed with the outer peripheral surface of the transmission wheel 2212 and the outer peripheral surface of the screw sleeve 2211, so as to reliably transmit and connect the transmission wheel 2212 and the screw sleeve 2211. It can be understood that the transmission belt 2213 of the present application can not only ensure the reliability of the transmission connection between the transmission wheel 2212 and the screw sleeve 2211, but also simplify the structure of the transmission member 221, so that the movement between the transmission wheel 2212 and the screw sleeve 2211 is stable, the noise is reduced, and the manufacturing cost of the rear wheel steering device 200 can also be reduced.

[0123] In one embodiment, the transmission member 221 further includes a tension wheel 2214, which is located between the transmission wheel 2212 and the screw sleeve 2211 along the radial direction of the transmission shaft 211. The outer peripheral surface of the tension wheel 2214 contacts the outer surface of the transmission belt 2213 and squeezes the transmission belt 2213 to keep the transmission belt 2213 in a taut state, thereby increasing the tension between the transmission belt 2213, the transmission wheel 2212 and the screw sleeve 2211, preventing the transmission belt 2213 from slipping, reducing the risk of the transmission belt 2213 jumping teeth, and thus ensuring the transmission efficiency and stability of the transmission member 221.

[0124] In one embodiment, the diameter of the transmission wheel 2212 in the transmission member 221 is smaller than the diameter of the screw sleeve 2211, so that the transmission member 221 can form a deceleration effect in the direction from the transmission shaft 211 to the screw sleeve 2211. The transmission member 221 can be used to adjust the speed and torque of the driving force output by the steering motor 10, and transmit the adjusted driving force to the tie rod 30. Specifically, during the rotation of the motor shaft 11 of the steering motor 10, the transmission member 221 can reduce the speed of the screw sleeve 2211 and amplify the driving force output by the steering motor 10, so as to effectively ensure the lateral displacement of the tie rod 30 driven by the screw sleeve 2211.

[0125] Please see Figure 8 A partial structural schematic diagram of a rear wheel steering gear 200 provided in one embodiment of the present application is shown.

[0126] like Figure 8 As shown, the rear wheel steering device 200 provided by the present application further includes a clutch 40, which is used to drive and connect the motor shaft 11 of the steering motor 10 and the transmission shaft 211. The driving force output by the steering motor is transmitted to the transmission shaft 211 through the clutch 40, and the transmission shaft 211 is used to drive the tie rod 30 to move along its own axial direction, and the tie rod 30 is used to drive the two rear wheels 1002 to steer.

[0127] Specifically, a clutch 40 includes an input member 41, an output member 42 and two menisci 43. One end of an input member 41 is used for transmission connection to a steering motor 10, and the other end of an input member 41 includes a pair of axial protrusions, and the pair of axial protrusions are arranged at intervals along the radial direction of a clutch 40. Each axial protrusion in a pair of axial protrusions is used for transmission connection to a menisci 43. One end of an output member 42 includes another pair of axial protrusions, and the other end of an output member 42 is used for transmission connection to a transmission shaft 211. Another pair of axial protrusions are arranged at intervals along the radial direction of a clutch 40, and the arrangement direction of the other pair of axial protrusions is perpendicular to the arrangement direction of the pair of axial protrusions. The two menisci 43 are arranged at intervals along the arrangement direction of the pair of axial protrusions, and the gap between the two menisci 43 is used to accommodate another pair of axial protrusions.

[0128] For details, please refer to Figure 9-12 .in Fig. 9 A schematic structural diagram of a clutch 40 of a rear wheel steering device 200 provided in an embodiment of the present application; Fig.10 A schematic diagram of the exploded structure of the clutch 40 of the rear wheel steering device 200 provided in one embodiment of the present application; Fig.11 A schematic cross-sectional structure diagram of a clutch 40 of a rear wheel steering device 200 provided in an embodiment of the present application; Fig.12This is a schematic cross-sectional structure diagram from another perspective of the clutch 40 of the rear wheel steering device 200 provided in an embodiment of the present application.

[0129] For ease of description, one end of an input member 41 along the axial direction of a clutch 40 is defined as a first end 411, and the other end of an input member 41 along the axial direction of a clutch 40 is defined as a second end. A pair of axial protrusions included at the second end of an input member 41 is a first pair of axial protrusions 413, and the first pair of axial protrusions 413 includes two first axial protrusions 4131 arranged at intervals along the radial direction of the clutch 40.

[0130] One end of an output member 42 along the axial direction of a clutch 40 is defined as a third end 421, and the other end of an output member 42 along the axial direction of a clutch 40 is defined as a fourth end. Another pair of axial protrusions included in the third end 421 of an output member 42 is a second pair of axial protrusions 423, and the second pair of axial protrusions 423 includes two second axial protrusions 4231 arranged at intervals along the radial direction of the clutch 40.

[0131] Thus, the first end 411 of the input member 41 is used for transmission connection to the motor shaft 11 of the steering motor 10. The second end of the input member 41 transmits two menisci 43 through the first pair of axial protrusions 413. One of the first axial protrusions 4131 is used for transmission connection to one menisci 43, and the other first axial protrusion 4131 is used for transmission connection to the other menisci 43. The arrangement direction of the two first axial protrusions 4131 in the first pair of axial protrusions 413 is the same as the arrangement direction of the two menisci 43.

[0132] The fourth end of the output member 42 is used for transmission connection to the transmission shaft 211. The third end 421 of the output member 42 is embedded in the gap between the two menisci 43 through the second pair of axial protrusions 423. The arrangement direction of the two second axial protrusions 4231 in the second pair of axial protrusions 423 is perpendicular to the arrangement direction of the two menisci 43 and the arrangement direction of the two first axial protrusions 4131.

[0133] Thus, along the axial direction of one clutch 40, two menisci 43 are arranged between the first end 411 of the input member 41 and the fourth end of the output member 42. The second end of the input member 41 and the third end 421 of the output member 42 are arranged between the first end 411 of the input member 41 and the fourth end of the output member 42. The two menisci 43 and the two second axial protrusions 4231 of the second pair of axial protrusions 423 are arranged alternately along the circumferential direction of the clutch 40. The two first axial protrusions 4131 of the first pair of axial protrusions 413 and the two second axial protrusions 4231 of the second pair of axial protrusions 4231 are arranged alternately along the circumferential direction of the clutch 40.

[0134] When the rear wheel steering device 200 provided by the present application outputs driving force through a steering motor 10, the motor shaft 11 of the steering motor 10 is used to drive the first end 411 of the input member 41 to rotate around the axis of the clutch 40. The second end 412 of the input member 41 is used to drive the first pair of axial protrusions 413 to rotate around the axis of the clutch 40. Each first axial protrusion 4131 of the first pair of axial protrusions 413 is used to drive a meniscus 43 to rotate around the axis of the clutch 40. Because the two second axial protrusions 4231 of the second pair of axial protrusions 423 are arranged in the gap between the two meniscus 43, the two meniscus 43 can push the second pair of axial protrusions 423 to rotate around the axis of the clutch 40. Correspondingly, the fourth end of the output member 42 can rotate around the axis of the clutch 40 with the third end 421 of the output member 42, and drive the transmission shaft 211 to rotate around the axis of the clutch 40. In this way, the clutch 40 can transmit the driving force output by the steering motor 10 to the transmission shaft 211.

[0135] Because the two first axial protrusions 4131 of the first pair of axial protrusions 413 are arranged at intervals along the radial direction of the clutch 40, the position where each first axial protrusion 4131 is meshed and transmitted with a meniscus 43 is far away from the axis of the clutch 40. The force radius between the first pair of axial protrusions 413 of the input member 41 and the two meniscus 43 is large, and the contact stress is correspondingly reduced. The torque bearing capacity between the input member 41 and the two meniscus 43 is correspondingly improved, and can withstand a larger torque output of the steering motor 10.

[0136] Correspondingly, the two second axial protrusions 4231 of the second pair of axial protrusions 423 are also arranged at intervals along the radial direction of the clutch 40, and the position where each second axial protrusion 4231 is meshed and transmitted with the two menisci 43 is also far away from the axis of one clutch 40. The force radius between the second pair of axial protrusions 423 of the output member 42 and the two menisci 43 is larger, and the contact stress is correspondingly reduced. The torque bearing capacity between the output member 42 and the two menisci 43 is also improved to withstand a larger torque output of the steering motor 10.

[0137] The rear-wheel steering gear 200 provided in the present application is arranged in a coordinated manner through the above-mentioned input member 41, output member 42, and two menisci 43, so that the arrangement directions of the first pair of axial protrusions 413 and the second pair of axial protrusions 423 are perpendicular to each other, and the meshing points of each first axial protrusion 4131 and each second axial protrusion 4231 with the two menisci 43 are far away from the axis of a clutch 40. The force radius between the input member 41 and the output member 42 relative to the two menisci 43 is large and the contact stress is small, thereby increasing the torque bearing capacity of the rear-wheel steering gear 200 provided in the present application and improving the reliability of the rear-wheel steering gear 200 provided in the present application.

[0138] In one embodiment, the first pair of axial protrusions 413 of the input member 41 are symmetrically arranged along the radial direction of one clutch 40 .

[0139] In one embodiment, the second pair of axial protrusions 423 of the output member 42 are symmetrically arranged along the radial direction of one clutch 40 .

[0140] For the above two embodiments, when the rear-wheel steering gear 200 provided in the present application outputs driving force through a steering motor 10, during the circumferential rotation of the input member 41 or the output member 42 around a clutch 40, the radius of action between the first pair of axial protrusions 413 or the second pair of axial protrusions 423 and the two menisci 43 are respectively equal, and the circumferential force on the two menisci 43 along the clutch 40 is relatively balanced, thereby increasing the torque bearing capacity of the two menisci 43 and improving reliability.

[0141] In one embodiment, the spacing between the two first axial protrusions 4131 in the first pair of axial protrusions 413 of the input member 41 is equal to the spacing between the two second axial protrusions 4231 in the second pair of axial protrusions 423 of the output member 42. At this time, the force radius of the two menisci 43 cooperating with the input member 41 is equal to the force radius of the two menisci 43 cooperating with the output member 42, which further improves the force conditions of the two menisci 43 along the circumferential direction of the clutch 40, increases the torque bearing capacity of the two menisci 43 and improves reliability.

[0142] In one embodiment, a clutch 40 includes a housing 44, and the housing 44 is used to accommodate two menisci 43. For details, see Fig.13 and Fig.14 .in Fig.13 This is a schematic structural diagram of a meniscus 43 in a rear wheel steering device 200 provided in an embodiment of the present application. Fig.14 This is a schematic structural diagram of two menisci 43 arranged in a housing 44 of a clutch 40 in a rear wheel steering device 200 provided in an embodiment of the present application.

[0143] like Fig.13 and Fig.14 As shown, each meniscus 43 in the clutch 40 includes an arcuate surface 431 and a plane 432. The arcuate surface 431 and the plane 432 of the meniscus 43 are oriented in opposite directions. The two arcuate surfaces 431 of the two meniscus 43 arranged at intervals are oriented in opposite directions, and each arcuate surface 431 is used to face the inner wall of the housing 44 of the clutch 40 along the arrangement direction of the first pair of axial protrusions 413. The inner wall of the housing 44 is used to abut the arcuate surface 431 of each meniscus 43. The two planes 432 of the two meniscus 43 are oriented in opposite directions, and the spacing between the two planes 432 is greater than the circumferential width of the second pair of axial protrusions 423. The second pair of axial protrusions 423 extend into the gap between the two planes 432.

[0144] In this embodiment, when the arcuate surfaces 431 of the two menisci 43 are respectively in contact with the housing 44, the housing 44 of the clutch 40 forms a friction force by contacting the arcuate surfaces 431 of the two menisci 43, thereby limiting the circumferential rotation of the two menisci 43. The second pair of axial protrusions 423 accommodated in the gap between the two menisci 43 are also limited to rotate along the circumferential direction of the clutch 40. The rear wheel steering device 200 provided by the present application also limits the rotation of a transmission shaft 211 through a clutch 40, thereby achieving the effect of limiting the axial displacement of a tie rod 30 by a clutch 40.

[0145] Therefore, when the vehicle 1000 is traveling on an uneven road surface and the two rear wheels 1002 make unexpected turns, the rear wheel steering device 200 of the present application can limit the axial displacement of a tie rod 30 through a clutch 40 to limit the angle of the unexpected turns of the two rear wheels 1002, thereby ensuring the smooth travel of the vehicle 1000 and reducing the frequency of intervention of a steering motor 10 to limit the unexpected turns of the two rear wheels 1002. The power consumption of the rear wheel steering device 200 of the present application is lower, and the service life of the steering motor 10 is longer.

[0146] For the rear wheel steering device 200 provided in the present application, before a steering motor 10 rotates, a clutch 40 is used to limit the rotation of a transmission shaft 211. During the rotation of a steering motor 10, a clutch 40 is used to drive a transmission shaft 211 to rotate with a steering motor 10.

[0147] Specifically, the clutch 40 is used to drive or lock the transmission shaft 211 through two menisci 43 and the output member 42. The clutch 40 is used to receive the drive of the steering motor 10 to drive the transmission shaft 211, and the clutch 40 is also used to lock the transmission shaft 211 before receiving the drive of the steering motor 10.

[0148] Please see Figure 15-17 .in Fig.15 This is a structural schematic diagram of a rear wheel steering device 200 provided in an embodiment of the present application in an initial state. Fig.16 A schematic diagram of the structure of a rear wheel steering device 200 provided in an embodiment of the present application, in which an input member 41 drives two menisci 43 and an output member 42 to rotate; Fig.17 A schematic diagram of the structure of two menisci 43 limiting the rotation of the output member 42 in a rear wheel steering device 200 provided in an embodiment of the present application.

[0149] like Fig.15As shown, when the rear-wheel steering gear 200 provided in the present application is in an initial state, the first pair of axial protrusions 413 of the input member 41 and the second pair of axial protrusions 423 of the output member 42 do not contact the two menisci 43 respectively.

[0150] like Fig.16 As shown, during the rotation of the steering motor 10, the steering motor 10 drives the input member 41 to rotate through the motor shaft 11. The first pair of axial protrusions 413 of the input member 41 drive the two menisci 43 to move relative to each other and drive the two menisci 43 to abut against the second pair of axial protrusions 423 of the output member 42. The two menisci 43 abut against the second pair of axial protrusions 423 of the output member 42 to drive the output member 42 to rotate synchronously.

[0151] That is, during the rotation of the motor shaft 11 of the steering motor 10, the steering motor 10 is used to drive the two meniscus plates 43 of the clutch 40 to drive the output member 42 and the transmission shaft 211 to rotate synchronously. The clutch 40 and the transmission shaft 211 are used to transmit the driving force of the steering motor 10 to the tie rod 30 to drive one tie rod 30 to move axially, thereby driving the two rear wheels 1002 to steer.

[0152] like Fig.17 As shown, before the motor shaft 11 of the steering motor 10 rotates, when the rear wheel 1002 is impacted by the ground and turns unexpectedly, the rear wheel 1002 will drive the tie rod 30 to move in the opposite direction along its own axial direction, thereby driving the transmission mechanism 20 to drive the output member 42 of the clutch 40 to rotate in the opposite direction. The second pair of axial protrusions 423 of the output member 42 abuts against the two menisci 43 to drive the two menisci 43 to move in opposite directions, so that the two menisci 43 respectively abut against the inner wall of the housing 44 and form friction. The two menisci 43 are limited in rotation under the action of the friction, thereby limiting the further rotation of the second pair of axial protrusions 423.

[0153] Thus, before the steering motor 10 rotates, the housing 44 of the clutch 40 forms a friction force by abutting against the arcuate surfaces 431 of the two menisci 43, thereby limiting the circumferential rotation of the two menisci 43. The two menisci 43 limit the rotation of the transmission shaft 211 through the output member 42. The clutch 40 is able to limit the axial displacement of the tie rod 30 through the transmission mechanism 20, thereby limiting the steering angle of the rear wheel 1002 when an unexpected turn occurs. In this process, the steering motor 10 does not need to rotate, and the rear wheel steering device 200 provided in the present application can limit the steering angle of the rear wheel 1002 through the clutch 40.

[0154] Therefore, the rear wheel steering device 200 provided by the present application can reduce the frequency of the intervention of the steering motor 10 to limit the unexpected steering of the two rear wheels 1002. It avoids the situation where the steering motor 10 is driven to work in a locked state for a long time to limit the unexpected steering of the two rear wheels 1002. The service life of the steering motor 10 is extended, and the power consumption of the rear wheel steering device 200 provided by the present application is reduced.

[0155] Corresponding to the embodiment in which the transmission mechanism 20 includes the screw sleeve 2211, based on the characteristics of the screw sleeve 2211 meshing with the tie rod 30, the axial displacement generated by the rotation of the screw sleeve 2211 driving the tie rod 30 is relatively small, and the rear wheel steering device 200 provided by the present application limits the rotation angle of the transmission shaft 211 through the clutch 40, and the axial displacement generated by the transmission shaft 211 transmitted to the tie rod 30 is also relatively small, that is, the angle of the unintended steering of the two rear wheels 1002 under the limiting effect of the clutch 40 is relatively small. The clutch 40 can ensure that the vehicle 1000 is in a relatively stable driving state.

[0156] Corresponding to the above-mentioned embodiment in which the transmission mechanism 20 forms a deceleration effect, the angle of the two rear wheels 1002 that produces an unexpected turning angle is further limited under the limiting effect of the clutch 40.

[0157] In one embodiment, the housing 44 of a clutch 40 includes an input side housing 441 and an output side housing 442 , wherein the input side housing 441 and the output side housing 442 are adjacently arranged along the axial direction of the clutch 40 , and the output side housing 442 is used to enclose an input side housing 441 .

[0158] For details, please refer to Fig.18 and Fig.19 .in Fig.18 This is a schematic diagram of the exploded structure of the housing 44 in the rear wheel steering device 200 provided in one embodiment of the present application. Fig.19 A schematic structural diagram of the cooperation between two menisci 43 and a shell 44 in a rear wheel steering device 200 provided in an embodiment of the present application.

[0159] like Fig.18 As shown, the input side housing 441 and the output side housing 442 are arranged adjacent to each other along the axial direction of the clutch 40, and the input side housing 441 is located between the output side housing 442 and the motor stator of the steering motor 10 along the axial direction of the clutch 40. The output side housing 442 is used to enclose the input side housing 441 to form the housing 44 of the clutch 40.

[0160] In one embodiment, an input side housing 441 is used to accommodate two menisci 43 and an input member 41. One of the output side housings 442 includes a mounting surface, and the mounting surface includes a plurality of bolt holes 4422, each of which is used to pass a bolt 443. An input side housing 441 includes another mounting surface, and the other mounting surface is used to fix an output side housing 442, and the other mounting surface includes a plurality of bolt slots 4412, and each bolt slot 4412 is used to fix and accommodate a bolt 443 passing through a bolt hole 4422.

[0161] For ease of description, another mounting surface of the input-side housing 441 is defined as a first mounting surface 4413 , and one mounting surface of the output-side housing 442 is defined as a second mounting surface 4423 .

[0162] The input side housing 441 and the output side housing 442 are arranged adjacent to each other along the axial direction of the clutch 40, and the output side housing 442 is used to enclose the input side housing 441 to form the housing 44 of the clutch 40. At this time, the first mounting surface 4413 is in contact with the second mounting surface 4423. The input side housing 441 and the output side housing 442 are enclosed to form the inner cavity of the housing 44, and the inner cavity of the housing 44 is used to accommodate two menisci 43.

[0163] On the outside of the housing 44, a plurality of bolts 443 pass through a bolt slot 4412 and a bolt hole 4422 in sequence to fix the input side housing 441 and the output side housing 442. Inside the housing 44, the input side housing 441 is used to accommodate two menisci 43 and the input member 41, and the output side housing 442 is used to accommodate the output member 42.

[0164] In one embodiment, an input side housing 441 is used to fix the outer ring of a bearing, and the inner ring of a bearing is used to fix the first end 411 of an input member 41. An output side housing 442 is used to fix the outer ring of another bearing, and the inner ring of another bearing is used to fix the fourth end of an output member 42.

[0165] For the convenience of description, one bearing accommodated in the input-side housing 441 is defined as a first bearing 451 , and another bearing accommodated in the output-side housing 442 is defined as a second bearing 452 .

[0166] The rear wheel steering gear 200 of the present application also accommodates two bearings through the housing 44 of the clutch 40. Each bearing is used to support an input member 41 or an output member 42 to ensure that the input member 41 and the output member 42 rotate smoothly around the axis of the clutch 40. Among them, the outer ring of the first bearing 451 is fixed to the inner wall of the input side housing 441, and the inner ring of the first bearing 451 is used to fix the first end 411 of the input member 41. The outer ring of the second bearing 452 is fixed to the inner wall of the output side housing 442, and the inner ring of the second bearing 452 is used to fix the fourth end of the output member 42.

[0167] In one embodiment, the clutch 40 further accommodates two menisci 43 through the input side housing 441, that is, the input side housing 441 is used to form the inner wall of the housing 44. Because the input side housing 441 is close to a steering motor 10, a steering motor 10 is fixed to the frame 1001 of the vehicle 1000. The structural stability of the input side housing 441 is better than that of the output side housing 442, and the input side housing 441 facilitates better support and abutment of the two menisci 43.

[0168] In one embodiment, the inner wall of an input-side housing 441 or the arcuate surface 431 of each meniscus 43 includes a plurality of radial grooves 4414 , and the plurality of radial grooves 4414 are arranged at intervals along the circumference of a clutch 40 .

[0169] For details, please refer to Fig.19 .exist Fig.19 In the schematic diagram, the inner wall of the input side housing 441 is annular, and the inner wall of the input side housing 441 includes a plurality of radial grooves 4414. The notch of each radial groove 4414 faces the axis of the clutch 40, and the extension direction of each radial groove 4414 is parallel to the axis of the clutch 40. The plurality of radial grooves 4414 are arranged at intervals along the circumference of a clutch 40, and the plurality of radial grooves 4414 can increase the friction between the inner wall of the input side housing 441 and the arcuate surfaces 431 of the two menisci 43, so that when the arcuate surfaces 431 of the two menisci 43 abut against the inner wall of the housing 44 respectively, the circumferential rotation of the output member 42 is better restricted.

[0170] On the other hand, multiple radial grooves 4414 can be used to store powder formed after wear of each meniscus 43 and the inner wall of the input side shell 441, reducing the influence of the powder on the friction between the arc surface 431 of each meniscus 43 and the inner wall of the input side shell 441, and better limiting the circumferential rotation of the output member 42.

[0171] In one embodiment, an arc surface 431 and a plane 432 of each meniscus 43 are connected by an arc segment 433. The arc segment 433 is used to form a guiding function for the arc surface 431 of the meniscus 43 during the rotation of the two menisci 43 around the axis of the clutch 40, thereby avoiding interference between the two ends of the two menisci 43 along the arrangement direction of the second pair of axial protrusions 423 and the multiple radial grooves 4414, thereby ensuring that the two menisci 43 rotate more flexibly and improving the transmission efficiency of the rear wheel steering gear 200 provided in the present application.

[0172] In one embodiment, the first end 411 of an input member 41 includes an internal spline, and the spacing between the first pair of axial protrusions 413 in the second end of an input member 41 is greater than the outer diameter of the first end 411 of an input member 41 .

[0173] For details, see Fig. 20 . Fig. 20 A schematic structural diagram of an input member 41 of a rear wheel steering device 200 provided in one embodiment of the present application.

[0174] like Fig. 20 As shown, the input member 41 includes a first positioning plate 414. The first positioning plate 414 is used to fix the first end 411 and the second end of the input member 41 along the axial direction of the clutch 40. Specifically, along the axial direction of a clutch 40, the first positioning plate 414 includes a first plate surface 4141 and a second plate surface 4142 that are opposite to each other. The first plate surface 4141 is used to face the motor stator of the steering motor 10, and the first plate surface 4141 is used to fix the first transmission column 4143, the first transmission column 4143 includes an internal spline, and the first transmission column 4143 is used to connect the motor shaft 11 of the steering motor 10 through the internal spline transmission.

[0175] The second plate surface 4142 is used to fix the first pair of axial protrusions 413. The first transmission column 4143 is used to receive the drive of the motor shaft 11 through the internal spline and is used to drive the first pair of axial protrusions 413 to rotate around the axis of the clutch 40 through the first positioning plate 414. A central hole is provided between the first plate surface 4141 and the second plate surface 4142, and the central hole is used to avoid the motor shaft 11 to increase the meshing length of the first transmission column 4143 and the motor shaft 11.

[0176] In one embodiment, the distance between the two first axial protrusions 4131 in the first pair of axial protrusions 413 is greater than the outer diameter of the first transmission column 4143. The distance between the first pair of axial protrusions 413 is relatively large to increase the radius of force between the input member 41 and the two menisci 43.

[0177] In one embodiment, the dimension of the first positioning plate 414 along the arrangement direction of the first pair of axial protrusions 413 is greater than the dimension along the arrangement direction of the second pair of axial protrusions 423. Because the first positioning plate 414 is used to fix the first transmission column 4143 and the first pair of axial protrusions 413, reducing the dimension of the first positioning plate 414 along the arrangement direction of the second pair of axial protrusions 423 can reduce the volume of the first positioning plate 414 and reduce the weight.

[0178] In one embodiment, the fourth end of one output member 42 includes another internal spline, and the spacing between the second pair of axial protrusions 423 in one end of one output member 42 is greater than the outer diameter of the fourth end of one output member 42 .

[0179] For details, see Fig.21 . Fig.21 A schematic diagram of the structure of an output member 42 of a rear wheel steering device 200 provided in one embodiment of the present application.

[0180] like Fig.21 As shown, the output member 42 includes a second positioning plate 424. The second positioning plate 424 is used to fix the third end 421 and the fourth end of the output member 42 along the axial direction of the clutch 40. Specifically, along the axial direction of a clutch 40, the second positioning plate 424 includes a third plate surface 4241 and a fourth plate surface 4242 that are opposite to each other. The fourth plate surface 4242 is oriented away from the motor stator of the steering motor 10. The fourth plate surface 4242 is used to fix the second transmission column 4243, the second transmission column 4243 includes another internal spline, and the second transmission column 4243 is used to connect the transmission shaft 211 through another internal spline.

[0181] The third plate surface 4241 is used to fix the second pair of axial protrusions 423. The second transmission column 4243 is used to receive the drive of the motor shaft 11 through another internal spline and is used to drive the first pair of axial protrusions 413 to rotate around the axis of the clutch 40 through the first positioning plate 414. A central hole is also included between the third plate surface 4241 and the fourth plate surface 4242, and the central hole is used to avoid the transmission shaft 211 to increase the meshing length of the second transmission column 4243 and the transmission shaft 211.

[0182] In one embodiment, the distance between the two second axial protrusions 4231 in the second pair of axial protrusions 423 is greater than the outer diameter of the second transmission column 4243. The distance between the second pair of axial protrusions 423 is relatively large to increase the radius of force between the output member 42 and the two menisci 43.

[0183] In one embodiment, the dimension of the second positioning plate 424 along the arrangement direction of the first pair of axial protrusions 413 is smaller than the dimension along the arrangement direction of the second pair of axial protrusions 423. Because the second positioning plate 424 is used to fixedly connect the second transmission column 4243 and the second pair of axial protrusions 423, reducing the dimension of the second positioning plate 424 along the arrangement direction of the first pair of axial protrusions 413 can reduce the volume of the second positioning plate 424 and reduce the weight.

[0184] In other embodiments, the first transmission column 4143 and the second transmission column 4243 may also be respectively connected to the motor shaft 11 and the transmission shaft 211 through external splines.

[0185] In one embodiment, each first axial protrusion 4131 in the first pair of axial protrusions 413 includes two cylindrical embedded portions 4132, and each meniscus 43 includes two trapezoidal through holes 434, each trapezoidal through hole 434 is used to accommodate an embedded portion 4132, and the long side 4341, short side 4342, hypotenuse 4343 and bottom side 4344 of each trapezoidal through hole 434 are respectively connected by an arc segment 4345.

[0186] For details, please refer to Figure 22-Figure 25 .in Fig. 22 A schematic diagram of the structure of the input member 41 and a meniscus 43 of the rear wheel steering device 200 provided in one embodiment of the present application; Fig.23 A schematic diagram of the exploded structure of the input member 41 of the rear wheel steering device 200 provided in one embodiment of the present application cooperating with a meniscus 43; Fig.24 A schematic diagram of a planar structure of the input member 41 and two menisci 43 of a rear wheel steering device 200 provided in an embodiment of the present application; Fig.25 A schematic plan view of the structure of the input member 41 of the rear wheel steering device 200 provided in one embodiment of the present application, in which the two menisci 43 cooperate to rotate.

[0187] like Figure 22-Figure 25 As shown, the first axial protrusion 4131 includes two embedded portions 4132, and the two embedded portions 4132 are arranged at intervals along the arrangement direction of the second pair of axial protrusions 423. In one embodiment, the two embedded portions 4132 are symmetrically arranged along the radial axis of the clutch 40. Each embedded portion 4132 is cylindrical, and the extension direction of each embedded portion 4132 is parallel to the axial direction of the clutch 40. The two embedded portions 4132 are used to be respectively embedded in one meniscus 43 along the axial direction of the clutch 40. That is, the two first axial protrusions 4131 in the first pair of axial protrusions 413 are respectively connected to one meniscus 43 through the two cylindrical embedded portions 4132.

[0188] Correspondingly, each meniscus 43 includes at least one groove along the end surface of the clutch 40 facing the motor electronics of the steering motor 10. The at least one groove is used to accommodate the first axial protrusion 4131. In the illustrated embodiment, the at least one groove of each meniscus 43 is two trapezoidal through holes 434. The arrangement direction of the two trapezoidal through holes 434 is the same as the arrangement direction of the two embedded parts 4132. Each embedded part 4132 is used to embed a trapezoidal through hole 434, and drive a meniscus 43 to rotate by abutting against the hole wall of a trapezoidal through hole 434.

[0189] Please see Fig.26 .in Fig.26 A schematic diagram of the partial structure of two trapezoidal through holes 434 of a meniscus 43 of a rear wheel steering device 200 provided in one embodiment of the present application.

[0190] like Fig.26 As shown, each trapezoidal through hole 434 includes a long side 4341, a short side 4342, a hypotenuse 4343 and a bottom side 4344. One of the long sides 4341 and the short side 4342 is arranged along the arrangement direction of the second pair of axial protrusions 423. In one embodiment, the long sides 4341 of the two trapezoidal through holes 434 are arranged between the short sides 4342 of the two trapezoidal through holes 434, and the two trapezoidal through holes 434 are arranged symmetrically along the radial axis of a clutch 40. A hypotenuse 4343 and a bottom side 4344 are arranged along the arrangement direction of the first pair of axial protrusions 413. The bottom sides 4344 of the two trapezoidal through holes 434 are arranged between the hypotenuse 4343 of the two trapezoidal through holes 434. The long side 4341, the short side 4342, the hypotenuse 4343 and the bottom side 4344 of each trapezoidal through hole 434 are respectively connected by an arc segment 4345. An arc segment 4345 is used to connect the side hole walls of a trapezoidal through hole 434 to reduce the stress concentration in the trapezoidal through hole 434 .

[0191] In one embodiment, the distance between the oblique side 4343 and the bottom side 4344 of each trapezoidal through hole 434 is greater than the outer diameter of each embedded portion 4132. Along the arrangement direction of the first pair of axial protrusions 413, a gap is formed between each embedded portion 4132 and the trapezoidal through hole 434. Each embedded portion 4132 is used to move between the oblique side 4343 and the bottom side 4344 of a trapezoidal through hole 434 to drive the two menisci 43 to move relative to each other, and make the two menisci 43 spaced from the inner wall of the housing 44 of a clutch 40 during the rotation process with the first pair of axial protrusions 413.

[0192] Specifically, when the first pair of axial protrusions 413 rotate with the motor shaft 11, the first pair of axial protrusions 413 abut the bottom edge 4344 of the trapezoidal through hole 434 through each embedded portion 4132, so as to drive the two menisci 43 to be relatively close to each other along the arrangement direction of the first pair of axial protrusions 413, and separate the two menisci 43 from the inner wall of the shell 44, thereby eliminating the friction between the two menisci 43 and the inner wall of the shell 44, ensuring that the two menisci 43 rotate synchronously with the first pair of axial protrusions 413 and improving the transmission efficiency of the clutch 40.

[0193] Before the steering motor 10 rotates, when the second pair of axial protrusions 423 produce unexpected steering due to the two rear wheels 1002, the second pair of axial protrusions 423 rotate around the axis of the clutch 40 and push the two menisci 43 to move relatively away from each other along the arrangement direction of the first pair of axial protrusions 413. The arcuate surfaces 431 of the two menisci 43 respectively contact the inner wall of the housing 44 to form friction force, thereby limiting the rotation of the second pair of axial protrusions 423.

[0194] In one embodiment, the spacing between the two embedded portions 4132 along the circumference of a clutch 40 is smaller than the spacing between the long side 4341 and the short side 4342 of each trapezoidal through hole 434. In this embodiment, the spacing between the two embedded portions 4132 is smaller, and when an input member 41 rotates clockwise or counterclockwise, there is always an embedded portion 4132 abutting against the long side 4341 of a trapezoidal through hole 434 to drive a meniscus 43. The force radius of a meniscus 43 is larger and the torque bearing effect is better.

[0195] In another embodiment, each meniscus 43 includes an axial through hole 435 , and the axial through hole 435 is used to accommodate a first axial protrusion 4131 of the first pair of axial protrusions 413 .

[0196] For details, see Fig. 27 .in Fig. 27 A schematic plan view of the structure of an axial through hole 435 of a meniscus 43 and a first axial protrusion 4131 of a rear wheel steering device 200 provided in one embodiment of the present application.

[0197] like Fig. 27 As shown, an axial through hole 435 is symmetrical along the radial axis of a clutch 40, and the aperture size of an axial through hole 435 along the arrangement direction of the first pair of axial protrusions 413 decreases in the clockwise direction and in the counterclockwise direction respectively from the symmetry axis of an axial through hole 435. Each axial protrusion in the first pair of axial protrusions 413 is inserted into an axial through hole 435 to drive connect a meniscus 43.

[0198] Because an axial through hole 435 is symmetrical along the radial axis of a clutch 40, along the circumferential direction of a clutch 40, the apertures at both ends of an axial through hole 435 are smaller than the aperture in the middle of an axial through hole 435. When rotating, the first axial protrusion 4131 first abuts against the radial hole wall of an axial through hole 435 to drive a meniscus 43 to move along the arrangement direction of the first pair of axial protrusions 413, and make a meniscus 43 spaced from the inner wall of the housing 44 of a clutch 40. The first axial protrusion 4131 then abuts against the circumferential hole wall on one side of an axial through hole 435 to drive a meniscus 43 to rotate.

[0199] It can be understood that in this embodiment, the spacing between the two relative hole walls of an axial through hole 435 along the arrangement direction of the first pair of axial protrusions 413 is greater than the outer diameter of the first axial protrusion 4131, and thus a gap is formed between the first axial protrusion 4131 and the one axial through hole 435 along the arrangement direction of the first pair of axial protrusions 413, allowing the first axial protrusion 4131 to move in the one axial through hole 435 to drive the two menisci 43 to move relative to each other. The spacing between the two relative hole walls of an axial through hole 435 along the arrangement direction of the second pair of axial protrusions 423 is greater than the outer diameter of the first axial protrusion 4131, and thus a gap is formed between the first axial protrusion 4131 and the one axial through hole 435 along the arrangement direction of the second pair of axial protrusions 423, allowing the first axial protrusion 4131 to move in the one axial through hole 435 to drive the one menisci 43 to rotate around the axis of the clutch 40.

[0200] In one embodiment, the gap between the two menisci 43 is used to install at least one elastic member 45, and the two ends of each elastic member 45 along the arrangement direction of the first pair of axial protrusions 413 are respectively used to abut against a meniscus 43, and at least one elastic member 45 is used to push the arc surface 431 of each meniscus 43 to move along the arrangement direction of the first pair of axial protrusions 413 toward the inner wall of a housing 44 of a clutch 40.

[0201] See also Fig.28 .in Fig.28 This is a schematic plan view of the structure of the two menisci 43 and the elastic member 45 of the rear wheel steering device 200 provided in one embodiment of the present application.

[0202] Specifically, Fig.28As shown, in this embodiment, the clutch 40 includes two elastic members 45, and the two elastic members 45 are arranged at intervals along the arrangement direction of the second pair of axial protrusions 423. The opposite ends of each elastic member 45 along the arrangement direction of the first pair of axial protrusions 413 are respectively used to abut a plane 432 of a meniscus 43. The two elastic members 45 are used to push the two meniscus 43 to abut against the inner wall of the housing 44 of a clutch 40 along the arrangement direction of the first pair of axial protrusions 413, so as to keep the two meniscus 43 abutting against the inner wall of the housing 44 of a clutch 40 and form friction before an input member 41 rotates. Therefore, before a steering motor 10 rotates, a clutch 40 can be used to maintain the restriction on the rotation of an output member 42.

[0203] During the rotation of the steering motor 10 , the input member 41 drives the two menisci 43 through the first pair of axial protrusions 413 to overcome the elastic force of the two elastic members 45 and move relatively close to each other along the arrangement direction of the first pair of axial protrusions 413 .

[0204] In one embodiment, along the arrangement direction of the second pair of axial protrusions 423, each elastic member 45 is located between the second pair of axial protrusions 423. Fig.28 In the schematic diagram, the two elastic members 45 are located between the two second axial protrusions 4231 in the second pair of axial protrusions 423. This ensures that the spacing between the two second axial protrusions 4231 in the second pair of axial protrusions 423 is relatively large. As a result, the force radius of the second pair of axial protrusions 423 and the two menisci 43 is larger to ensure the torque bearing capacity of the clutch 40. Such an arrangement also makes the structure of a clutch 40 more compact, reducing the overall volume of the rear wheel steering device 200 provided by the present application.

[0205] In one embodiment, the material of each elastic member 45 is a viscoelastic damping material. The elastic member 45 is used to provide damping when the two menisci 43 are relatively displaced along the direction of the first axial protrusion 413, so as to reduce the knocking noise generated when the two menisci 43 are in relative contact.

[0206] In one embodiment, each elastic member 45 is made of rubber or polyurethane sponge.

[0207] In one embodiment, one of the two menisci 43 includes a protrusion 4361, and the other of the two menisci 43 includes a groove 4362. A protrusion 4361 of one menisci 43 is used to be embedded in a groove 4362 of the other menisci 43.

[0208] See also Fig.29 and Fig.30 .in Fig.29A schematic diagram of the planar structure of the two menisci 43 of the rear wheel steering device 200 provided in one embodiment of the present application; Fig.30 This is a schematic diagram of the exploded structure of the two menisci 43 of the rear wheel steering device 200 provided in one embodiment of the present application.

[0209] Specifically, Fig.29 and Fig.30 As shown, a protrusion 4361 and a groove 4362 in the two menisci 43 both extend along the arrangement direction of the first pair of axial protrusions 413. A protrusion 4361 extends from the plane 432 of one menisci 43 toward the other menisci 43, and a groove 4362 is recessed from the plane 432 of the other menisci 43, and the notch of a groove 4362 faces the plane 432 of one menisci 43 along the arrangement direction of the first pair of axial protrusions 413. After a protrusion 4361 is embedded in a groove 4362, the side wall of a protrusion 4361 abuts against the groove wall of a groove 4362, so that a guiding function can be formed when the two menisci 43 are relatively displaced.

[0210] In the illustrated embodiment, each meniscus 43 includes a protrusion 4361 and a groove 4362 on one side facing the other meniscus 43, and a groove 4362 of one of the two meniscus 43 is used to accommodate a protrusion 4361 of the other meniscus 43. Thus, two pairs of mutually matching protrusions 4361 and grooves 4362 are alternately arranged, and the guide length of the two menisci 43 can be increased along the arrangement direction of the first pair of axial protrusions 413, so as to prevent the two protrusions 4361 from falling off from the two grooves 4362 at the same time.

[0211] In one embodiment, at least one of the two surfaces of a protrusion 4361 and a groove 4362 that match each other includes a coating layer. That is, at least one of the side wall of a protrusion 4361 or the groove wall of a groove 4362 includes a coating layer. The coating layer is a phosphide layer or a molybdenum disulfide layer, and the coating layer is used to reduce the wear between a protrusion 4361 and a groove 4362.

[0212] In one embodiment, along the arrangement direction of the second pair of axial protrusions 423, a protrusion 4361 and a groove 4362 on a meniscus 43 are both located between the second pair of axial protrusions 423. This can make the structure of a clutch 40 more compact while ensuring that the force radius of the second pair of axial protrusions 423 is larger, thereby reducing the overall volume of the rear wheel steering gear 200 provided in the present application.

[0213] In one embodiment, one end of each elastic member 45 is used to fix a protrusion 4361 of one meniscus 43 , and the other end of each elastic member 45 is used to fix a bottom of a groove 4362 of another meniscus 43 .

[0214] In this embodiment, an elastic member 45 is installed by utilizing the space between the bottom of a protrusion 4361 and a groove 4362. On the premise of ensuring the coordination of a protrusion 4361 and a groove 4362, and the function of an elastic member 45 pushing two menisci 43, the structure of a clutch 40 can be made more compact and the overall volume of the rear wheel steering gear 200 provided in this application can be reduced.

[0215] In the illustrated embodiment, two elastic members 45 are also fixed between a protrusion 4361 and a groove 4362. The two elastic members 45 are arranged at intervals along the axial direction of the clutch 40. The two elastic members 45 can make the elastic force between a protrusion 4361 and a groove 4362 evenly distributed, and reliably push the meniscus 43 on both sides.

[0216] In one embodiment, at least one of the end of a protrusion 4361 and the bottom of a groove 4362 includes a receiving groove, and the receiving groove is used to accommodate one end of an elastic member 45. At least one of a protrusion 4361 and a groove 4362 is used to partially accommodate and fix the elastic member 45 to improve the structural stability of the elastic member 45 and ensure that the elastic force direction of the elastic member 45 is parallel to the arrangement direction of the first pair of axial protrusions 413.

[0217] In one embodiment, each meniscus 43 includes two receiving grooves 437, and the groove of each receiving groove 437 in each meniscus 43 faces the other meniscus 43, and one receiving groove 437 of each meniscus 43 cooperates with one receiving groove 437 of another meniscus 43 to accommodate one second axial protrusion 4231 in the second pair of axial protrusions 423, and another receiving groove 437 of each meniscus 43 cooperates with another receiving groove 437 of another meniscus 43 to accommodate the other second axial protrusion 4231 in the second pair of axial protrusions 423.

[0218] Please see Figure 31-Figure 33 .in Fig.31 A schematic diagram of the structure of the output member 42 of the rear wheel steering device 200 provided in one embodiment of the present application cooperating with two menisci 43; Fig.32 A schematic diagram of the exploded structure of the output member 42 of the rear wheel steering device 200 provided in one embodiment of the present application and the cooperation between the two menisci 43; Fig.33 This is a schematic plan view of the structure of the output member 42 of the rear wheel steering device 200 and the two menisci 43 provided in one embodiment of the present application.

[0219] Specifically, Figure 31-Figure 33As shown, each meniscus 43 respectively accommodates a part of the structure of the two second axial protrusions 4231 in the second pair of axial protrusions 423 through two accommodating grooves 437, that is, the two second axial protrusions 4231 in the second pair of axial protrusions 423 are respectively embedded in the two accommodating grooves 437 of one meniscus 43. Therefore, along the circumferential direction of the clutch 40, the size of the two second axial protrusions 4231 in the second pair of axial protrusions 423 is larger, which improves the torque bearing capacity of the second pair of axial protrusions 423.

[0220] In one embodiment, the slot width of each receiving slot 437 is smaller than the slot bottom width, and each receiving slot 437 includes a first slot wall 4371 and a second slot wall 4372. The axial distance between a first slot wall 4371 and a clutch 40 in each receiving slot 437 is smaller than the axial distance between a second slot wall 4372 and a clutch 40. That is, the first slot wall 4371 in each receiving slot 437 is closer to the axis of the clutch 40 than the second slot wall 4372. For two receiving slots 437 in the same meniscus 43, along the arrangement direction of the second pair of axial protrusions 423, the two first slot walls 4371 are located between the two second slot walls 4372. The two first slot walls 4371 can be used to abut against a second axial protrusion 4231, respectively.

[0221] In one embodiment, the curvature of a first groove wall 4371 in each accommodating groove 437 is greater than the curvature of a second groove wall 4372, the bending direction of a first groove wall 4371 in each accommodating groove 437 is away from a second groove wall 4372, the bending directions of the first groove walls 4371 of the two accommodating grooves 437 in each meniscus 43 are opposite, and the bending directions of the first groove walls 4371 of the two matching accommodating grooves 437 in the two menisci 43 are the same.

[0222] In this embodiment, the first groove wall 4371 of each receiving groove 437 close to the axis of one clutch 40 is formed as an arc-shaped groove wall. The center of the arc-shaped groove wall is close to the axis of one clutch 40. The first groove wall 4371 is able to form a guiding function for one of the second axial protrusions 4231 in the second pair of axial protrusions 423, guiding the second pair of axial protrusions 423 to rotate around the axis of one clutch 40. The bending directions of the first groove walls 4371 of the two matching receiving grooves 437 in the two menisci 43 are the same, that is, in the two receiving grooves 437 where the same second axial protrusion 4231 is embedded, the two first groove walls 4371 respectively form a guiding effect on the second axial protrusion 4231 in the clockwise direction and the counterclockwise direction, thereby guiding the second axial protrusion 4231 to rotate around the axis of the clutch 40.

[0223] In one embodiment, each second axial protrusion 4231 in the second pair of axial protrusions 423 is bent toward another second axial protrusion 4231. The dimension of each second axial protrusion 4231 in the second pair of axial protrusions 423 along the circumferential direction of one clutch 40 is greater than the dimension along the radial direction of one clutch 40. The curvature of each second axial protrusion 4231 in the second pair of axial protrusions 423 is greater than or equal to the curvature of the first groove wall 4371 of each meniscus 43.

[0224] In this embodiment, each second axial protrusion 4231 in the second pair of axial protrusions 423 is arc-shaped, and the arc-shaped second axial protrusion 4231 can fit with the two accommodating grooves 437 to enhance the guiding effect between the first groove wall 4371 and the second axial protrusion 4231 .

[0225] In one embodiment, a protrusion 4361 , a groove 4362 and two receiving grooves 437 of a meniscus 43 are all located on a plane 432 .

[0226] For details, please refer to Fig.34 . Fig.34 The schematic diagram of the structure of the meniscus 43 in the rear wheel steering device 200 provided in one embodiment of the present application. As shown in the figure, the plane 432 of a meniscus 43 includes a protrusion 4361, a groove 4362 and two receiving grooves 437. Along the arrangement direction of the second pair of axial protrusions 423, a protrusion 4361 and a groove 4362 are arranged between the two receiving grooves 437. As a result, the distance between the two receiving grooves 437 is larger, which is conducive to improving the torque bearing capacity of the meniscus 43.

[0227] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of protection of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A rear wheel steering gear, characterized in that: The rear wheel steering device comprises a clutch, a transmission shaft and a tie rod, wherein the clutch is used to drive a steering motor and the transmission shaft, the transmission shaft is used to drive the tie rod to move along the axial direction of the tie rod, and the tie rod is used to drive the two rear wheels to steer, and the clutch comprises an input member, an output member and two menisci, wherein: One end of the input member is used for transmission connection with the steering motor, and the other end of the input member includes a pair of axial protrusions, the pair of axial protrusions are arranged at intervals along the radial direction of the clutch, and each of the pair of axial protrusions is used for transmission connection with one of the menisci; One end of the output member includes another pair of axial protrusions, the other end of the output member is used for transmission connection with the transmission shaft, the other pair of axial protrusions are arranged at intervals along the radial direction of the clutch, and the arrangement direction of the other pair of axial protrusions is perpendicular to the arrangement direction of the pair of axial protrusions; The two menisci are arranged at intervals along the arrangement direction of the pair of axial protrusions, and the gap between the two menisci is used to accommodate the other pair of axial protrusions.

2. The rear wheel steering gear according to claim 1, characterized in that: The housing of the clutch is used to accommodate the two menisci, the arcuate surface of each meniscus faces the inner wall of the housing along the arrangement direction of the pair of axial protrusions, and the inner wall of the housing is used to abut the arcuate surface of each meniscus.

3. The rear wheel steering gear according to claim 1, characterized in that: Each of the pair of axial protrusions includes two cylindrical embedded parts, each of the menisci includes two trapezoidal through holes, each of the trapezoidal through holes is used to accommodate one of the embedded parts, and the long side, short side, oblique side and bottom side of each of the trapezoidal through holes are respectively connected by an arc segment.

4. The rear wheel steering gear according to claim 3, characterized in that: The long sides of the two trapezoidal through holes are arranged between the short sides of the two trapezoidal through holes, the two trapezoidal through holes are symmetrically arranged along the radial axis of the clutch, and the distance between the hypotenuse and the base in each trapezoidal through hole is greater than the outer diameter of each embedded part.

5. The rear wheel steering gear according to claim 3, characterized in that: The distance between the two embedded portions along the circumferential direction of the one clutch is smaller than the distance between the long side and the short side of each of the trapezoidal through holes.

6. The rear wheel steering gear according to claim 1, characterized in that: Each of the menisci includes an axial through hole, which is used to accommodate one of the pair of axial protrusions. The axial through hole is symmetrical along the radial axis of the clutch, and the aperture of the axial through hole decreases in a clockwise direction and a counterclockwise direction from the symmetry axis of the axial through hole.

7. The rear wheel steering gear according to claim 1, characterized in that: The gap between the two menisci is used to install at least one elastic member, and each of the elastic members is used to abut against one of the menisci at both ends along the arrangement direction of the pair of axial protrusions, and the at least one elastic member is used to push the arc surface of each meniscus to move along the arrangement direction of the pair of axial protrusions toward the inner wall of the housing of the clutch.

8. The rear wheel steering gear according to claim 7, characterized in that: Each of the menisci comprises a protrusion and a groove on one side facing the other menisci, and the groove of one of the two menisci is used to accommodate the protrusion of the other menisci, wherein: One end of each of the elastic members is used for fixedly connecting to a protrusion of one of the menisci, and the other end of each of the elastic members is used for fixedly connecting to the bottom of a groove of another of the menisci.

9. The rear wheel steering gear according to claim 1, characterized in that: Each of the menisci includes two receiving grooves, and the groove of each of the receiving grooves in each of the menisci faces the other menisci. One of the receiving grooves of each of the menisci cooperates with one of the receiving grooves of the other menisci to accommodate one of the other pair of axial protrusions, and the other receiving groove of each of the menisci cooperates with the other receiving groove of the other menisci to accommodate the other axial protrusion of the other pair of axial protrusions.

10. The rear wheel steering gear according to claim 9, characterized in that: The slot width of each of the accommodating slots is smaller than the slot bottom width, each of the accommodating slots comprises a first slot wall and a second slot wall, and the axial distance between the first slot wall and the clutch in each of the accommodating slots is smaller than the axial distance between the second slot wall and the clutch, wherein: The curvature of the first groove wall in each of the accommodating grooves is greater than the curvature of the second groove wall, the bending direction of the first groove wall in each of the accommodating grooves is away from the second groove wall, the bending directions of the first groove walls of the two accommodating grooves in each of the menisci are opposite, and the bending directions of the first groove walls of the two matching accommodating grooves in the two menisci are the same.

11. The rear wheel steering gear according to claim 1, characterized in that: Each of the axial protrusions in the other pair of axial protrusions is bent toward the other axial protrusion, wherein: The dimension of each of the axial protrusions in the other pair of axial protrusions along the circumferential direction of the one clutch is greater than the dimension along the radial direction of the one clutch; The curvature of each of the other pair of axial protrusions is greater than or equal to the curvature of the first groove wall of each meniscus.

12. The rear wheel steering gear according to claim 1, characterized in that: The housing of the clutch comprises an input side housing and an output side housing, the output side housing and the output side housing are arranged adjacent to each other along the axial direction of the clutch, and the output side housing is used to enclose the input side housing, wherein: The input side housing is used to fix the outer ring of a bearing, and the inner ring of the bearing is used to fix the one end of the input member; The one output side housing is used to fix the outer ring of another bearing, and the inner ring of the other bearing is used to fix the other end of the one output member.

13. The rear wheel steering device according to claim 12, characterized in that: The one end of the one input member includes an internal spline, and the spacing between the pair of axial projections in the other end of the one input member is greater than the outer diameter of the one end of the one input member; The other end of the one output member comprises another internal spline, and the spacing between the other pair of axial protrusions in the one end of the one output member is greater than the outer diameter of the other end of the one output member.

14. The rear wheel steering gear according to claim 12, characterized in that: The one input side housing is used to accommodate the two menisci and the one input member, wherein: The output side housing comprises a mounting surface, the mounting surface comprises a plurality of bolt holes, each of the bolt holes is used to pass a bolt; The one input side housing comprises another mounting surface, the another mounting surface is used to fix the one output side housing, the another mounting surface comprises a plurality of bolt grooves, each of the bolt grooves is used to fix and accommodate one of the bolts passing through one of the bolt holes; The inner wall of the one input side housing or the arcuate surface of each of the menisci comprises a plurality of radial grooves, and the plurality of radial grooves are arranged at intervals along the circumference of the one clutch.

15. A vehicle, characterized in that: The vehicle comprises two rear wheels and a rear wheel steering gear as claimed in any one of claims 1 to 14, wherein the rear wheel steering gear is used to drive the two rear wheels to change the direction.

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