Automobile steering control system

Abstract

The invention relates to an automobile steering control system which comprises a steering motor comprising a motor shell and a motor output shaft; the steering gear comprises a steering gear input shaft, and the steering gear input shaft is in transmission connection with the motor output shaft so as to transmit steering torque to wheels; the locking device is arranged outside the motor output shaft in a sleeving mode, located between a motor shell and a steering gear input shaft in the axial direction and used for locking the motor output shaft by controlling the locking device to be locked with the motor shell so that the steering gear can be locked at the rotating position of any angle. The locking device is close to the power input end, impact force of the wheels is transmitted to the locking device after torque reduction of the steering gear, impact on the locking device is small, locking torque needed by the wheels is small, and unlocking energy consumption is low. Under the same rack or lead screw output force as a self-locking steering gear, the steering gear is high in power transmission efficiency, small in steering motor output torque, low in power and small in size. Meanwhile, loads borne by all parts in the steering gear are small, and the size of the steering gear is small.

Description

Technical Field

[0001] The invention relates to the technical field of automobile steering systems, and in particular to an automobile steering control system with a locking function. Background Art

[0002] At present, the steering of the vehicle is mainly achieved by the driver controlling the steering wheel to achieve the angle deflection of the front wheels and change the direction of the vehicle. With the development of automobile autonomous driving technology and the increasing requirements for vehicle stability, new technologies such as wire control steering, four-wheel independent distributed steering, and rear-wheel steering have emerged.

[0003] The four-wheel independent distributed steering gear and rear wheel steering gear can reduce the turning radius of the vehicle and improve the flexibility and controllability when turning and parking. The stability and safety of the vehicle can be improved by coordinating the control of the front and rear wheels. The stability of the vehicle when turning at high speed can be improved by steering the rear wheels.

[0004] The steer-by-wire system eliminates the mechanical connection components between the steering wheel and the steering wheel. The driver's operating actions are converted into electrical signals and transmitted to the actuator. It is a technology that realizes autonomous driving.

[0005] For the above-mentioned types of steering gears, when it is necessary to solve the influence of vehicle failure and large ground impact on the tire position, a locking function is required to keep the wheel in a fixed position. In the related art, the automobile steering system adopts a self-locking mechanism in the transmission mechanism to realize the locking function, such as worm gear self-locking, planetary roller screw self-locking or trapezoidal screw self-locking. The transmission efficiency of this type of self-locking mechanism is generally less than 40%, which is very low.

[0006] In addition, for worm gear self-locking steering gears, due to the increase in the required input torque, it is necessary to use a very expensive tin bronze worm gear to replace the common nylon worm gear to withstand the large load, which increases the cost.

[0007] In the JP2014121904 patent, an electromagnetic latch mechanism is added to the output rack to achieve the wheel neutral lock. Since the lock is located at the output end of the steering gear, the impact force acts directly on the lock mechanism without torque reduction, and the lock mechanism requires a large power to unlock. In addition, this lock mechanism can only achieve neutral lock, not any position lock. Summary of the invention

[0008] In order to overcome the problems existing in the related art, the present disclosure provides a vehicle steering system.

[0009] According to a first aspect of an embodiment of the present disclosure, the present disclosure provides an automobile steering control system, characterized in that it includes: a steering motor, including a motor housing and a motor output shaft; a steering gear, including a steering gear input shaft, the steering gear input shaft is drivingly connected to the motor output shaft to transmit steering torque to the wheels; and a locker, which is sleeved on the outside of the motor output shaft and axially located between the motor housing and the steering gear input shaft; wherein the motor output shaft is locked by controlling the locker to lock with the motor housing, so as to lock the steering gear in a rotation position of any angle.

[0010] In some embodiments, the lock is an electromagnetic lock, including: a stator, which is torsionally connected to the motor housing, and a coil is arranged in the stator; a rotor, which is torsionally connected to the motor output shaft, and the rotor includes a radial portion, and the radial portion is axially located between the stator and the motor housing; an armature, which is axially movable between the stator and the radial portion, wherein the armature is controlled to move axially by controlling the power on and off of the coil to loosen or clamp the radial portion between the armature and the motor housing.

[0011] In some embodiments, the lock further includes a flange, which is rigidly connected to the motor housing and axially located between the radial portion of the rotor and the motor housing, and the radial portion of the rotor is clamped to the motor housing through the flange.

[0012] In some embodiments, the stator further comprises a spring, and when the coil is de-energized, the spring pushes the armature to move axially so as to clamp the radial portion of the rotor between the armature and the motor housing.

[0013] In some embodiments, the rotor further includes an axial portion integrally formed with the radial portion, wherein the axial portion is radially located between the armature and the motor output shaft.

[0014] In some embodiments, the axial portion is axially movable relative to the motor output shaft via a spline, so that the radial portion can be axially separated from the flange.

[0015] In some embodiments, the outer wall of the motor output shaft is provided with a sleeve, the sleeve is radially located between the motor output shaft and the axial portion of the rotor, the outer wall of the sleeve is provided with the spline, and the inner wall of the sleeve is torsionally connected to the motor output shaft through a flat key and a keyway.

[0016] In some embodiments, the radial portion of the rotor is wrapped with a friction pad.

[0017] In some embodiments, the lock also includes a long pin, which axially penetrates the stator, the armature and the flange, so that the stator, the armature and the flange are torsionally connected, and the armature can move axially relative to the long pin.

[0018] In some embodiments, the lock also includes a transfer shell, the flange is located inside the transfer shell, the outer wall of the first end of the transfer shell is rigidly connected to the motor housing, and the flange is rigidly connected to the inner wall of the first end of the transfer shell to achieve a rigid connection with the motor housing.

[0019] In some embodiments, the lock further includes a waterproof breathable valve, which is installed in the adapter housing and can connect the interior of the adapter housing with the exterior for heat dissipation of the lock.

[0020] In some embodiments, the automobile steering system also includes a control device for controlling the state of the lock, wherein the conditions for controlling whether the lock is locked include: when driving at medium and high speeds, the steering mode requires a locking function, the steering motor is powered off, the lock is powered off and locked, and the wheels remain in position; when driving at low speeds, the steering mode does not require a locking function, the steering motor is powered off, and the wheels remain in position.

[0021] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0022] First, the locker is arranged close to the motor output shaft, that is, close to the power input end of the entire vehicle steering system. The impact force transmitted from the wheel end needs to be reduced by the torque of the steering gear before being transmitted to the locker, so the impact on the locker is small.

[0023] Second, the lock is close to the power input end, and the lock only needs a small locking torque to lock the wheel, so the unlocking energy consumption is also low.

[0024] Third, compared with the self-locking steering gear, due to the high transmission efficiency of this steering control system, under the same rack or lead screw output force, the required steering motor output torque is small, there is no need to use a high-power, high-energy steering motor, and the size of the steering motor is also reduced.

[0025] Fourth, the output torque of the steering motor is required to be small, and the load borne by the components in the steering gear is also small, so the volume of the steering gear can be reduced accordingly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0027] Figure 1 is a structural principle diagram of a vehicle steering system according to an exemplary embodiment;

[0028] Figure 2 is a schematic diagram of a three-dimensional structure of a vehicle steering system according to an exemplary embodiment;

[0029] Figure 3 is a longitudinal sectional view of a vehicle steering system according to an exemplary embodiment;

[0030] Figure 3A yes Figure 3 A partial enlarged view of the middle part;

[0031] Figure 4 is a longitudinal cross-sectional view of a vehicle steering system at a spring according to an exemplary embodiment;

[0032] Figure 4A yes Figure 4 A partial enlarged view of point B in the middle;

[0033] Figure 5 is a transverse cross-sectional view of an automobile steering system according to an exemplary embodiment, wherein the cross-sectional view is a worm gear reduction mechanism and a rack and pinion reduction mechanism of a steering gear;

[0034] Figure 6 yes Figure 5 Schematic diagram of the three-dimensional structure of the worm gear reduction mechanism and the rack and pinion reduction mechanism;

[0035] Figure 7 is a structural principle diagram of a vehicle steering system according to another exemplary embodiment;

[0036] Figure 8 The figure is a flow chart of a control method of a vehicle steering system according to an exemplary embodiment. DETAILED DESCRIPTION

[0037] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0038] In the present invention, unless otherwise specified, the axial direction A, radial direction R and circumferential direction refer to the axial direction A, radial direction R and circumferential direction of the lock, respectively; the axial end refers to Figure 3 The left side of the axis is Figure 3In the right side. In addition, "transmission connection" refers to the ability to transmit driving force / torque between two components, and the two components can be directly connected or through various transmission mechanisms or connection structures to achieve the above functions. The terms "torsion-resistant connection" and "rigid connection" refer to the connection between two elements in a manner that does not rotate relative to each other, which can be achieved through a press fit (i.e., interference fit) or by forming the two mentioned components into one piece. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0039] In order to solve the above technical problems, the present disclosure provides a vehicle steering system 100, such as Figure 1 and Figure 7 As shown, the automobile steering system 100 includes a steering motor 10, a steering gear 20, a lock 30, a CAN bus (Controller Area Network) and an ECU (Automobile Control Unit).

[0040] The steering motor 10 includes a motor housing 11 and a motor output shaft 12. The motor output shaft 12 is located at one axial end of the motor housing 11. Figures 3 to 4A Left end shown.

[0041] The steering gear 20 is drivingly connected to the steering motor 10 , and the steering gear 20 is equivalent to a reducer, which plays a role of reducing speed and increasing torque, and is used to transmit the steering torque of the steering motor 10 to the wheels, so as to control the rotation of the wheels.

[0042] The steering gear 20 includes a steering gear input shaft, a steering gear output shaft, and a power transmission mechanism located between the steering gear input shaft and the steering gear output shaft.

[0043] In the first embodiment of the present disclosure, Figure 3 As shown, the steering gear 20 includes a worm gear reduction mechanism and a rack and pinion reduction mechanism, so the steering gear input shaft is equivalent to the worm 21 in the worm gear reduction mechanism, and the steering gear output shaft is equivalent to the rack 24 in the rack and pinion reduction mechanism.

[0044] In the second embodiment of the present disclosure, Figure 7 As shown, the steering gear 20 includes a belt reduction mechanism and a ball screw reduction mechanism, so the steering gear input shaft is equivalent to the small pulley 26 in the belt reduction mechanism, and the steering gear output shaft is equivalent to the screw 29 in the ball screw reduction mechanism.

[0045] The steering gear 20 also includes a tie rod 25, which is connected between the wheel and the steering gear output shaft. In the first embodiment, the tie rod 25 is connected to the rack 24. In the second embodiment, the tie rod 25 is connected to the screw rod 29, and the linear motion of the rack 24 or the screw rod 29 drives the tie rod 25 to move, thereby realizing the steering of the wheel.

[0046] Furthermore, the steering gear input shaft of the steering gear 20 and the motor output shaft 12 may be coaxial (as in the present embodiment). Figure 4 In the first embodiment of the present disclosure, as shown in FIG. Figure 3A As shown, the output end of the motor output shaft 12 is connected to the input end of the worm 21 through the fixing seat 202 and the coupling 203 to realize the power transmission from the steering motor 10 to the steering gear 20.

[0047] In this disclosure, Figures 1 to 7 As shown, the locker 30 is sleeved on the outside of the motor output shaft 12 and is axially located between the motor housing 11 and the steering gear input shaft. The locker 30 is controlled to lock with the motor housing 11 to lock the motor output shaft 12 so as to lock the steering gear 20 at any rotational position.

[0048] Specifically, Figures 1 to 7 As shown, the other axial end of the lock 30 (such as Figure 3A and Figure 4A The right end of the steering gear 20 is rigidly connected to the left end of the steering motor 10. The lock 30 is not only close to the steering motor 10, but also rigidly connected to the motor housing 11 of the steering motor 10, so that the lock 30 is almost located at the power input end of the entire automobile steering system 100, away from the wheel end. The impact force transmitted from the wheel end needs to be transmitted to the lock 30 after the torque reduction of the steering gear 20, thereby reducing the influence of the wheel impact on the lock 30 and extending the service life of the lock 30.

[0049] The locker 30 is close to the power input end. According to the lever principle, only a small locking torque is needed to lock the remote wheel, and when the locker 30 is unlocked, the unlocking energy consumption is also low.

[0050] In the related art, the steering gear 20 with a power transmission mechanism having a self-locking function will reduce the transmission efficiency of the power transmission mechanism. However, since the present disclosure is provided with a locker 30, the steering gear 20 no longer needs to use a power transmission mechanism having a self-locking function, thereby making the transmission efficiency of the automobile steering system 100 high. Under the same output force of the rack 24, the required output torque of the steering motor 10 is small, and there is no need to use a high-power, high-energy-consuming steering motor 10, which reduces the cost of the steering motor 10 and also reduces the volume of the steering motor 10. Since the output torque of the steering motor 10 is small, the load borne by the various components in the steering gear 20 (such as the coupling 203, the worm wheel 22, the worm 21, etc.) is also small, so that the volume of the steering gear 20 can also be reduced accordingly, which can further reduce the cost of the steering gear 20 and the space occupied.

[0051] Furthermore, in some embodiments, the lock 30 may be an electromagnetic lock 30. Specifically, Figures 3 to 4A As shown, the lock 30 includes a flange 31 , a stator 32 , a rotor 33 and an armature 34 , and the flange 31 , the stator 32 , the rotor 33 and the armature 34 are all sleeved on the outside of the motor output shaft 12 .

[0052] Specifically, the flange 31 is disposed near the input end of the motor output shaft 12 and is rigidly connected to the motor housing 11. The stator 32 is disposed near the output end of the motor output shaft 12, and the stator 32 and the flange 31 are spaced apart in the axial direction and are torsionally connected to the flange 31.

[0053] The working end face of the stator 32 is an axial end face and is arranged opposite to the flange 31. The stator 32 includes a coil (such as Figure 3 and 3A As shown); an annular coil groove is provided in the middle of the stator 32, and the annular coil groove is arranged around the central axis of the motor output shaft 12. The coil groove extends axially from the working end surface to the inside of the stator 32, and the coil groove is used to accommodate the coil 321. The coil 321 is energized to enable the stator 32 to generate magnetic attraction.

[0054] The rotor 33 includes a radial portion 331, which is located between the stator 32 and the flange 31 along the axial direction A. By controlling the abutment or disconnection between the radial portion 331 of the rotor 33 and the flange 31, the rotor 33 is controlled to lock the motor output shaft 12 or rotate with the motor output shaft 12.

[0055] The radial portion 331 of the rotor 33 is connected to or disconnected from the flange 31 through the armature 34. The armature 34 is axially movable between the stator 32 and the radial portion 331 of the rotor 33. The armature 34 is driven to move axially by energizing or de-energizing the coil 321 to drive the radial portion 331 of the rotor 33 to disconnect from or connect with the flange 31.

[0056] The stator 32 further includes a spring 322, such as Figure 4A As shown, the spring 322 is axially extended and located inside the stator 32. One end of the spring 322 protrudes from the working end face of the stator 32, abuts against the armature 34 and applies elastic force to the armature 34 to move toward the radial portion 331 of the rotor 33 along the axial direction. When the coil 321 is powered off, the stator 32 no longer generates electromagnetic force, and the armature 34 cannot be attracted to move toward the working end face of the stator 32. The spring 322 elastically pushes the armature 34, clamping the radial portion 331 of the rotor 33 between the armature 34 and the flange 31 to generate a friction torque. Since the flange 31 is rigidly connected to the motor housing 11 of the steering motor 10, the motor output shaft 12 is locked. Therefore, when the coil 321 is powered off, the lock 30 is in a locked state, the position of the motor output shaft 12 is fixed, the pull rod 25 of the steering gear 20 cannot move, the position of the pull rod 25 is locked, and the direction of the wheel is fixed.

[0057] When the coil 321 is energized, the stator 32 attracts the armature 34, and the armature 34 no longer axially pushes or squeezes the radial portion 331 of the rotor 33, so that the radial portion 331 of the rotor 33 can be separated from the armature 34 and the flange 31, and the position of the motor output shaft 12 is no longer fixed. If the motor is started at this time, the motor output shaft 12 can rotate and transmit torque to the steering gear 20, and finally drive the rack 24 to move linearly to drive the pull rod 25 to move, thereby driving the wheel to rotate and adjusting the rotation direction of the wheel.

[0058] Among them, the radial portion 331 of the rotor 33 achieves frictional abutment with the motor housing 11 through the frictional abutment of the flange 31. In this way, the radial portion 331 of the rotor 33 can be prevented from directly frictionally abutting with the motor housing 11, thereby reducing the replacement frequency of the motor housing 11 and extending the service life of the steering motor 10.

[0059] It can be seen that the lock 30 adopts an electromagnetic lock 30, which controls the axial movement of the armature 34 to clamp or loosen the radial portion 331 of the rotor 33. The lock 30 can lock the motor output shaft 12 at any rotational position, thereby making the rack 24 of the steering gear 20 also stay at any linear position, and finally making it possible to fix the wheel at any rotational angle. The present invention can realize the locking of the wheel at any position, and has a wider range of applications.

[0060] In some embodiments, the radial portion 331 of the rotor 33 is wrapped with a friction pad 333. The friction pad 333 can be a metal fiber material, a semi-metal fiber material, or a mixed fiber material. When the coil 321 is powered off and the lock 30 is in the disconnected state, the radial portion 331 of the rotor 33 is clamped between the armature 34 and the flange 31, and the friction pad 333 can prevent the radial portion 331 of the rotor 33 from directly rubbing against the friction surfaces of the flange 31 and the armature 34, thereby reducing the wear and loss of the radial portion 331 of the rotor 33, the flange 31, and the armature 34, and extending the service life.

[0061] It can be seen from the above content that the stator 32 is torsionally connected to the flange 31. In some embodiments, the lock 30 also includes a long pin 36, which axially penetrates the stator 32, the armature 34 and the flange 31, so that the stator 32, the armature 34 and the flange 31 are torsionally connected, and the armature 34 moves axially relative to the long pin 36.

[0062] The long pin 36 can prevent the stator 32, the armature 34 and the flange 31 from moving relative to each other in the circumferential direction. The long pin 36 can also guide the armature 34 to move axially and fix the position of the armature 34 in the circumferential direction. When the armature 34 clamps the radial portion 331 of the rotor 33, the armature 34 cannot rotate circumferentially due to the long pin 36. When the radial portion 331 of the rotor 33 frictionally abuts against the armature 34, the radial portion 331 of the rotor 33 is better locked to prevent the rotor 33 and the motor output shaft 12 from rotating, which is more conducive to fixing the steering position of the wheel.

[0063] In some embodiments, Figure 3A and 4A As shown, the rotor 33 further includes an axial portion 332 integrally formed with the radial portion 331 . The axial portion 332 and the radial portion 331 are integrally formed, which increases the volume and strength of the rotor 33 without increasing the radial dimension, and the rotor 33 is not easily bent or damaged.

[0064] The axial portion 332 is radially located between the armature 34 and the motor output shaft 12 . The axial portion 332 is radially located between the armature 34 and the motor output shaft 12 . By limiting the radial movement of the axial portion 332 , the radial movement of the rotor 33 can be effectively avoided.

[0065] In some embodiments, the axial portion 332 is axially movable relative to the motor output shaft 12 via a spline, so as to enable the radial portion 331 to abut against or separate from the flange 31 .

[0066] A spline is provided on the inner wall of the axial portion 332, and the axial portion 332 can move axially relative to the motor output shaft 12 through the spline. Therefore, when the locker 30 is in a non-locked state, that is, the coil 321 is energized, the stator 32 adsorbs the armature 34, and the armature 34 cannot clamp the rotor 33 between the armature 34 and the flange 31. At this time, the radial portion 331 of the rotor 33 can also move axially, so that the radial portion 331 of the rotor 33 can be separated from the flange 31, thereby avoiding continuous friction between the radial portion 331 of the rotor 33 and the flange 31 when the motor output shaft 12 drives the rotor 33 to rotate, thereby extending the service life of the radial portion 331 of the rotor 33 and the flange 31.

[0067] In some embodiments, the outer wall of the motor output shaft 12 is sleeved with a sleeve 121. Specifically, the inner wall of the sleeve 121 is torsionally connected to the motor output shaft 12 through a flat key 122 and a keyway, and the outer wall of the sleeve 121 is torsionally connected to the inner wall of the axial portion 332 of the rotor 33 through a spline. The axial portion 332 of the rotor 33 is torsionally connected to the motor output shaft 12 through the sleeve 121.

[0068] In addition, the motor output shaft 12 is provided with a clamping groove at both axial ends of the keyway, and the shaft sleeve 121 is provided with a retaining spring 123 at both axial ends. The retaining spring 123 is inserted into the clamping groove to limit the axial ends of the shaft sleeve 121, axially limit the shaft sleeve 121, and avoid axial movement of the shaft sleeve 121.

[0069] The axial portion 332 of the rotor 33 is connected to the motor output shaft 12 in a circumferential torsion-resistant manner through the bushing 121, and realizes axial relative movement with the motor output shaft 12, which can avoid direct connection between the axial portion 332 of the rotor 33 and the motor output shaft 12. When the bushing 121 is worn, the bushing 121 can be directly replaced to avoid replacement of the motor output shaft 12 or the rotor 33, thereby extending the service life of the motor output shaft 12 and the rotor 33. The bushing 121 is connected to the motor output shaft 12 in a torsion-resistant manner through the flat key 122 and the keyway, which is also easier to disassemble, install and replace, thereby reducing costs.

[0070] In some embodiments, therefore, the lock 30 of the present disclosure further includes a transfer housing 35 , and the stator 32 , the rotor 33 , the armature 34 , the flange 31 of the lock 30 and the motor output shaft 12 of the steering motor 10 are all located in the transfer housing 35 .

[0071] The first end of the adapter housing 35 (ie Figure 3A and Figure 4A The right end in the middle is torsionally connected to the motor housing 11 by fasteners. The adapter housing 35 can make full use of the axial space to bring the locker 30 close to the power input end. The locker 30 only needs a small locking torque to lock the wheel, so the unlocking energy consumption is also low.

[0072] In addition, the flange 31 is rigidly connected to the adapter housing 35 through fasteners, and the flange 31 is torsionally connected to the motor housing 11 through the adapter housing 35 to avoid direct abutment between the flange 31 and the motor housing 11. Since the flange 31 needs to repeatedly accept the friction abutment of the radial portion 331 of the rotor 33, it wears faster. This can extend the life of the motor housing 11 and the adapter housing 35.

[0073] Since the lock 30 is usually used on the chassis of a vehicle, it is often affected by sewage, dust, gravel, etc. due to the special working conditions of the vehicle. The adapter housing 35 can also play a role of covering and protecting, reducing the impact of the external environment on the lock 30 and extending the service life of the lock 30.

[0074] In the first embodiment, the steering gear 20 includes a middle housing 304, in which the worm 21 is rotatably mounted and supported by a bearing. Figure 3 and Figure 3A The left end in the middle) is rigidly connected to the middle shell 304 by fasteners. From the above content, it can be seen that the first end of the adapter shell 35 is rigidly connected to the motor shell 11, so the axial ends of the adapter shell 35 are closed by other shells, so that a closed accommodating space is formed in the adapter shell 35.

[0075] Therefore, in some embodiments, the lock 30 may further include a waterproof breathable valve 37, which is installed in the adapter housing 35 (eg, Figures 3 to 4A The upper part of the adapter housing 35 can play a protective role, and the breathable valve 37 can connect the inside of the adapter housing 35 with the outside, which is used for ventilation and heat dissipation inside the lock 30.

[0076] In some embodiments, Figure 5 and Figure 6 As shown, the steering gear 20 includes a worm shaft 23, a worm gear reduction mechanism, a rack and pinion reduction mechanism, and a steering angle sensor (Steering Angle Sensor, SAS for short).

[0077] Specifically, the worm gear shaft 23 includes a worm gear shaft input end (such as Figure 5 The upper end of the gear shaft (such as Figure 5 worm gear reduction mechanism comprises a worm wheel 22 and a worm 21, the worm wheel 22 is torsionally sleeved on the input end of the turbine shaft, and the worm 21 is meshed with the worm wheel 22.

[0078] The gear rack 24 reduction mechanism includes a gear 231 and a rack 24. The gear is located at the output end of the worm shaft and meshes with the rack 24. The rack 24 is connected to one end of a pull rod 25, and the other end of the pull rod 25 is connected to the wheel. The linear motion of the rack 24 drives the pull rod 25 to move, thereby enabling the wheel to turn.

[0079] like Figure 2 As shown, the rotation angle sensor SAS is torsionally connected to the worm gear shaft 23. In particular, the rotation angle sensor SAS is installed at the upper end of the steering gear 20 and is torsionally connected to the input end of the worm gear shaft. It is used to collect the angle signal of the rotation of the worm gear shaft 23 and convert the angle signal into an electrical signal. The angle signal can be converted through the transmission ratio and reflects the rotation angle information of the wheel.

[0080] The vehicle control unit ECU is electrically connected to the controller area network bus (CAN bus), the angle sensor SAS, the lock 30 and the steering motor 10. The ECU transmits the instructions to the lock 30 and the steering motor 10 based on the wheel angle information collected by the SAS and the speed, current, temperature and other signals of the steering motor 10, combined with the angle signal instructions issued by the CAN bus, to complete the steering action of the wheel.

[0081] Compared with the self-locking steering gear 20 in the related art, the worm gear reduction mechanism and the rack and pinion reduction mechanism in the present invention do not need to be designed as a reduction mechanism with a self-locking function. Therefore, the steering gear 20 has low friction and power loss when transmitting the power of the steering motor 10 to the wheels, thereby improving the power transmission efficiency of the steering gear 20.

[0082] In addition, since the loads borne by the components in the steering gear 20 are small, the steering gear 20 disclosed in the present invention does not need to use a tin bronze worm gear 22 that bears high loads and is very expensive. Instead, a commonly used nylon worm gear 22 that can bear loads that meet the requirements and is low in cost can be used. In this way, the cost of the steering gear 20 can be reduced.

[0083] In addition, since the reverse self-locking characteristic of the self-locking steering gear 20 determines the unidirectionality of the movement, the steering motor 10 needs to be powered on to reset. If the program has not been calibrated, it is easy to reach the required position but the steering motor 10 does not stop rotating, resulting in the reset position not being the desired position. At this time, the motor can only be removed and manually reset to the required position at the input of the steering gear 20 by tools, which is time-consuming and complicated. However, the steering gear 20 disclosed in the present invention can reset the wheel or the steering gear 20 to the required position by manually rotating the wheel or pushing the output end of the steering gear 20 after the control lock 30 is unlocked, and the operation is simple.

[0084] In the second embodiment of the present disclosure, Figure 7 As shown, the steering gear 20 includes a belt reduction mechanism, a ball screw reduction mechanism and a displacement sensor 201.

[0085] Among them, the belt reduction mechanism includes a small pulley 26, a large pulley and a belt. The small pulley 26 is the steering gear input shaft, and the belt sleeve is arranged on the outer periphery of the small pulley 26 and the large pulley. The motor output shaft 12 of the steering motor 10 drives the small pulley 26 to rotate, and the small pulley 26 transmits power to the large pulley through the belt.

[0086] Furthermore, the ball screw reduction mechanism includes a screw 29 and a nut, the nut is sleeved on the outer wall of the screw 29, and the nut is equivalent to a large belt conveyor pulley, so that the ball screw 29 reduction mechanism is connected to the belt reduction mechanism. The belt drives the large belt pulley to rotate, and the rotation of the large belt pulley is converted into the linear motion of the screw 29. Therefore, the displacement sensor 201 is connected to the screw 29, and the displacement sensor 201 is used to detect the movement amount (i.e., displacement signal) of the linear displacement of the screw 29, thereby reflecting the rotation angle information of the wheel, and the displacement sensor 201 converts the displacement signal into an electrical signal and transmits it to the ECU.

[0087] The ECU transmits the displacement signal collected by the displacement sensor 201 and the speed, current, temperature and other signals of the steering motor 10 to the lock 30 and the steering motor 10 in combination with the angle signal command issued by the CAN bus, thereby completing the steering action of the wheel.

[0088] Based on the same inventive concept, the present disclosure provides a control method for an automobile steering system 100, the control method comprising the following steps: Figure 8 As shown, the steering mode is entered, the lock 30 is powered on and released, and the steering motor 10 is powered on. The steering motor 10 controls the target servo angle through current, speed, and angle closed-loop control. The target angle is given by the upper-level controller, which drives the wheel to steer. At the same time, the steering angle of the steering gear 20 is collected to determine whether the target angle has been reached. If not, the steering motor 10 is powered on and continues to rotate until the target angle is reached. If the target angle has been reached, it is determined whether the steering mode requires a locking function. If the locking function is required, such as when driving at medium and high speeds, the steering motor 10 is powered off, and then the lock 30 is powered off and locked, and the wheel remains in position. If the steering mode does not require a locking function, such as when driving at low speeds, the steering motor 10 is powered on and the wheel reaches the position. When the vehicle does not need to steer, the steering motor is powered off, the lock 30 is powered off and locked, and the wheel remains in position.

[0089] It is to be understood that in the present disclosure, "plurality" refers to two or more than two, and other quantifiers are similar. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. The singular forms "a", "the" and "the" are also intended to include plural forms, unless the context clearly indicates other meanings.

[0090] It is further understood that the terms "first", "second", etc. are used to describe various structures, but these structures should not be limited to these terms. These terms are only used to distinguish structures of the same type from each other, and do not indicate a specific order or importance. In fact, the expressions "first", "second", etc. can be used interchangeably. For example, without departing from the scope of the present disclosure, a first structure can also be referred to as a second structure, and similarly, a second structure can also be referred to as a first structure.

[0091] It should be further understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "inside", and "outside" are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation.

[0092] It can be further understood that, unless otherwise specified, “connection” includes a direct connection without other components between the two, and also includes an indirect connection with other components between the two.

[0093] It is further understood that, although the operations are described in a specific order in the drawings in the embodiments of the present disclosure, it should not be understood as requiring the operations to be performed in the specific order shown or in a serial order, or requiring the execution of all the operations shown to obtain the desired results. In certain environments, multitasking and parallel processing may be advantageous.

[0094] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following scope of rights.

[0095] It should be understood that the present disclosure is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the scope of the appended claims.

Claims

1. A vehicle steering control system (100), It is characterized in that include: A steering motor (10) comprises a motor housing (11) and a motor output shaft (12); A steering gear (20), comprising a steering gear (20) input shaft, the steering gear input shaft being drivingly connected to the motor output shaft (12) to transmit steering torque to the wheels; as well as A locker (30) is sleeved on the outside of the motor output shaft (12) and is axially located between the motor housing (11) and the input shaft of the steering gear (20); The motor output shaft (12) is locked by controlling the locker (30) to lock with the motor housing (11), so as to lock the steering gear (20) at a rotation position of any angle.

2. The vehicle steering control system (100) according to claim 1, It is characterized in that The lock (30) is an electromagnetic lock, comprising: A stator (32) is connected to the motor housing (11) in a torsion-resistant manner, and a coil (321) is provided in the stator (32); A rotor (33) is connected to the motor output shaft (12) in a torsion-proof manner, the rotor (33) comprising a radial portion (331), the radial portion (331) being axially located between the stator (32) and the motor housing (11); an armature (34) axially movably disposed between the stator (32) and the radial portion (331), The armature (34) is controlled to move axially by controlling the power on and power off of the coil (321), so as to loosen or clamp the radial portion (331) between the armature (34) and the motor housing (11).

3. The vehicle steering control system (100) according to claim 2, It is characterized in that The locker (30) further comprises a flange (31), wherein the flange (31) is rigidly connected to the motor housing (11) and is axially located between the radial portion (331) of the rotor (33) and the motor housing (11), and the radial portion (331) of the rotor (33) is clamped to the motor housing (11) via the flange (31).

4. The vehicle steering control system (100) according to claim 3, It is characterized in that The stator (32) further comprises a spring (322). When the coil (321) is de-energized, the spring pushes the armature (34) to move axially so as to clamp the radial portion (331) of the rotor (33) between the armature (34) and the motor housing (11).

5. The automobile steering control system (100) according to claim 3, It is characterized in that The rotor (33) further comprises an axial portion (332) formed integrally with the radial portion (331), wherein the axial portion (332) is radially located between the armature (34) and the motor output shaft (12).

6. The vehicle steering control system (100) according to claim 5, It is characterized in that The axial portion (332) is axially movable relative to the motor output shaft (12) via a spline, so that the radial portion (331) can be axially separated from the flange (31).

7. The vehicle steering control system (100) according to claim 6, It is characterized in that The outer wall of the motor output shaft (12) is provided with a shaft sleeve (121), the shaft sleeve (121) is radially located between the motor output shaft (12) and the axial portion (332) of the rotor (33), the outer wall of the shaft sleeve (121) is provided with the spline, and the inner wall of the shaft sleeve (121) is torsionally connected to the motor output shaft (12) via a flat key and a keyway.

8. The automobile steering control system (100) according to claim 2, It is characterized in that The radial portion (331) of the rotor (33) is wrapped with a friction pad (333).

9. The automobile steering control system (100) according to claim 3, It is characterized in that The lock (30) also includes a long pin (36), which axially penetrates the stator (32), the armature (34) and the flange (31), so that the stator (32), the armature (34) and the flange (31) are connected to each other in a torsion-proof manner, and the armature (34) can move axially relative to the long pin (36).

10. The automobile steering control system (100) according to claim 3, It is characterized in that The lock (30) further comprises a transfer housing (35), the flange (31) being located inside the transfer housing (35), the outer wall of the first end of the transfer housing (35) being rigidly connected to the motor housing (11), and the flange (31) being rigidly connected to the inner wall of the first end of the transfer housing (35) to achieve a rigid connection with the motor housing (11).

11. The vehicle steering control system (100) according to claim 10, It is characterized in that The locker (30) further comprises a waterproof breathable valve (37), which is installed on the adapter housing (35) and enables the interior of the adapter housing (35) to communicate with the outside, and is used for heat dissipation of the locker (30).

12. The automotive steering system (100) according to claim 1, It is characterized in that The automobile steering system (100) further comprises a control device for controlling the state of the lock (30), wherein the conditions for controlling whether the lock (30) is locked include: When driving at medium or high speeds, the steering mode requires a locking function, the steering motor (10) is powered off, the locker (30) is powered off and locked, and the wheels maintain their positions; When driving at low speed, the steering mode does not require a locking function, the steering motor (10) is powered off, and the wheels maintain their position.

Images