Steer-by-wire steering single pinion steering actuator with mechanical redundancy

Abstract

The application relates to the field of vehicle steering devices and discloses a steer-by-wire single pinion steering actuator with a mechanical redundancy structure, which comprises a rack shell, a middle shell symmetrically arranged on the top of the rack shell, an electric control unit fixedly connected to the side of the middle shell through a reduction assembly, a speed reduction assembly arranged in the middle shell and meshing with the reduction assembly, an adjusting assembly arranged in the rack shell and used for adjusting a gap, a sealing assembly arranged at the connection between the rack shell and the middle shell, and a connecting rod group arranged on the outside of the rack shell. The application has the following advantages and effects: the redundancy assembly is introduced into the steering system; the mechanical redundancy structure backs up key assemblies, such as a redundancy electric control unit, a double motor system, a redundancy sensor group and a redundancy power supply system; the whole system can still maintain functions and continue to provide steering support for drivers when a single component fails; meanwhile, the steer-by-wire system can better adapt to the requirements of unmanned driving and advanced auxiliary driving, and can provide necessary safety guarantee for high-order automatic driving.

Description

Technical Field

[0001] This invention relates to the field of vehicle steering technology, and in particular to a steer-by-wire single pinion steering actuator with a mechanical redundancy structure. Background Technology

[0002] Steer-by-wire systems eliminate the mechanical connection between the steering wheel and the steering wheels, controlling the steering actuators via electrical signals. They offer advantages such as flexible placement and ease of implementation of advanced driver assistance functions, making them a key technology for future intelligent connected and autonomous vehicles. A single pinion actuator is a mainstream structural form in steer-by-wire systems; it uses a motor to drive a pinion, which in turn drives a rack to achieve steering.

[0003] However, existing single-pinion actuators suffer from insufficient functional safety and redundancy. As a safety-critical component, the failure of a single motor or control unit can easily lead to a complete loss of steering function, causing serious safety accidents. This fails to meet the automotive industry's highest functional safety level (ASIL D) requirements for steering systems. With the development of autonomous driving technology, vehicles need to be able to drive safely in various complex environments, even when some components fail. Summary of the Invention

[0004] The purpose of this invention is to provide a steer-by-wire single-pinion steering actuator with a mechanically redundant structure, which can provide safety assurance for autonomous driving by utilizing the redundant mechanical structure.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a steer-by-wire single pinion steering actuator with a mechanical redundancy structure, comprising a rack housing, an intermediate housing symmetrically mounted on the top of the rack housing, an electronic control unit fixedly connected to the side of the intermediate housing via a reduction assembly, a speed reduction assembly meshing with the reduction assembly being disposed inside the intermediate housing, an adjustment assembly for adjusting the clearance being disposed inside the rack housing, a sealing assembly being disposed at the connection between the rack housing and the intermediate housing, the electronic control unit being connected to the sensor wiring harness assembly via bolt V, and a connecting rod assembly being disposed on the outer side of the rack housing.

[0006] A further configuration of the present invention is as follows: the deceleration assembly includes an elastic element, the electronic control unit is connected to the half coupling through the elastic element, the half coupling is press-fitted onto the first worm gear, and a four-point contact ball bearing and a deep groove ball bearing are sequentially installed inside the intermediate housing, with the two ends of the first worm gear respectively installed inside the four-point contact ball bearing and the deep groove ball bearing.

[0007] A further configuration of the present invention is as follows: the speed reduction assembly includes a gear shaft, the gear shaft is vertically rotatably mounted inside the intermediate housing, a worm wheel meshing with a first worm is fixedly mounted on the gear shaft, a sensor rotor and a sensor body are fixedly mounted on the gear shaft, a four-point contact ball bearing and a needle roller bearing are fixedly mounted at one end of the gear shaft, the four-point contact ball bearing is press-fitted into the intermediate housing, the needle roller bearing is press-fitted into the rack housing, and a rack meshing with the gear shaft is provided inside the rack housing.

[0008] A further configuration of the present invention is as follows: the gap assembly includes an adjusting stud, the adjusting stud is located inside the rack housing, and the rack pressure block is fixedly installed inside the rack housing by a locking nut cooperating with the adjusting stud.

[0009] A further configuration of the present invention is as follows: the sealing assembly includes a No. 1 ring; the electronic control unit and the intermediate housing are connected by bolt I; the No. 1 ring is assembled between the intermediate housing and the electronic control unit to provide a sealing function; the intermediate housing and the upper cover are connected by bolt III; the No. 2 ring is assembled between the intermediate housing and the upper cover to provide a sealing and noise reduction function; the intermediate housing and the rack housing are connected by bolt II; the No. 3 ring is assembled between the intermediate housing and the rack housing to provide a sealing and noise reduction function; and the No. 4 ring is assembled between the rack pressure block and the rack housing to provide a sealing and noise reduction function.

[0010] A further configuration of the present invention is as follows: the connecting rod assembly includes a bellows, the larger end of the bellows is fixedly installed on the outside of the rack housing by a large clamp, the smaller end of the bellows is fixedly installed on the inner tie rod by a small clamp, the inner tie rod is connected to the rack by a thread, and the inner tie rod is connected to the outer tie rod by a tie rod nut.

[0011] The beneficial effects of this invention are: by introducing redundant components into the steering system, the mechanical redundancy structure ensures that the entire system can still function and continue to provide steering support to the driver when a single component fails by backing up key components such as redundant electronic control units, dual motor systems, redundant sensor groups, and redundant power supply systems. At the same time, the steer-by-wire system can better adapt to the needs of autonomous driving and advanced driver assistance systems, providing the necessary safety guarantee for high-level autonomous driving. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1An exploded view of the structure of a steer-by-wire single pinion steering actuator with mechanical redundancy provided in an embodiment of the present invention;

[0014] Figure 2 This is a front view of the overall structure in an embodiment of the present invention;

[0015] Figure 3 This is a partial structural cross-sectional view at point AA in an embodiment of the present invention;

[0016] Figure 4 This is a partial structural cross-sectional view at point BB in an embodiment of the present invention;

[0017] Figure 5 This is a partial structural cross-sectional view of EE in an embodiment of the present invention;

[0018] Figure 6 This is a diagram showing the overall structure assembly and usage in an embodiment of the present invention.

[0019] In the diagram: 1. Rack housing; 2. Electronic control unit; 3. No. 1 O-ring; 4. Elastic element; 5. Half coupling; 6. Four-point contact ball bearing; 7. Worm gear; 8. Deep groove ball bearing; 9. Worm wheel; 10. No. 2 O-ring; 11. Top cover; 12. Gear shaft; 13. Sensor rotor; 14. Sensor body; 15. Intermediate housing; 16. Four-point contact ball bearing; 17. No. 3 O-ring; 18. Rack; 19. Needle roller shaft. 20. Rack and pinion block; 21. No. 4 O-ring; 22. Adjusting stud; 23. Locking nut; 24. Bolt I; 25. Bolt II; 26. Bolt III; 27. Bolt V; 28. Sensor harness assembly; 29. ​​Worm gear II; 30. Intermediate housing II; 31. Top cover II; 32. Large clamp; 33. Bellows; 34. Small clamp; 35. Inner tie rod; 36. Tie rod nut; 37. Outer tie rod. Detailed Implementation

[0020] The technical solution of the present invention will now be clearly and completely described with reference to specific embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] Reference Figure 1-6This invention specifically provides a drive-by-wire single pinion steering actuator with a mechanical redundancy structure, including a rack housing 1, an intermediate housing 15 symmetrically mounted on the top of the rack housing 1, an electronic control unit 2 fixedly connected to the side of the intermediate housing 15 via a reduction assembly, a speed reduction assembly meshing with the reduction assembly inside the intermediate housing 15, an adjustment assembly for adjusting the clearance inside the rack housing 1, sealing assemblies at the connection between the rack housing 1 and the intermediate housing 15, the electronic control unit 2 connected to the sensor wiring harness assembly 28 via bolts V27, and a connecting rod assembly on the outer side of the rack housing 1.

[0022] The deceleration assembly includes an elastic element 4. The electronic control unit 2 is connected to the half coupling 5 through the elastic element 4. The half coupling 5 is press-fitted onto the first worm gear 7. The interior of the intermediate housing 15 is sequentially equipped with a four-point contact ball bearing 6 and a deep groove ball bearing 8. The two ends of the first worm gear 7 are respectively installed inside the four-point contact ball bearing 6 and the deep groove ball bearing 8.

[0023] With the above structural setup, the electronic control unit 2 transmits torque to the worm gear I 7 through the elastic element 4. The rotation of the worm gear I 7 drives the worm wheel 9 to rotate, forming a worm gear reduction mechanism, as detailed in the BB view.

[0024] The speed reduction assembly includes a gear shaft 12, which is vertically rotatably mounted inside the intermediate housing 15. A worm wheel 9 that meshes with the first worm 7 is fixedly mounted on the gear shaft 12. A sensor rotor 13 and a sensor body 14 are fixedly mounted on the gear shaft 12. A four-point contact ball bearing 16 and a needle roller bearing 19 are fixedly mounted on one end of the gear shaft 12. The four-point contact ball bearing 16 is press-fitted into the intermediate housing 15, and the needle roller bearing 19 is press-fitted into the rack housing 1. A rack 18 that meshes with the gear shaft 12 is provided inside the rack housing 1.

[0025] With the above structural setup, the worm gear 9 drives the gear shaft 9 to rotate, and the gear shaft 9 pushes the rack 18 to move in a straight line repeatedly, thus forming a gear and rack speed reduction mechanism in cooperation with the rack 18.

[0026] The gap assembly includes an adjusting stud 22, an internal adjusting stud 22 in the rack housing 1, and a rack pressure block 20 which is fixedly installed inside the rack housing 1 by a locking nut 23 in cooperation with the adjusting stud 22.

[0027] With the above-mentioned structural configuration, the rack pressure block 20 is assembled in the rack housing 1 through the adjusting stud 22 and the locking nut 23, and plays the role of gap adjustment.

[0028] The sealing assembly includes a first O-ring 3, the electronic control unit 2 and the intermediate housing 15 are connected by bolt I24, the first O-ring 3 is installed between the intermediate housing 15 and the electronic control unit 2 to perform a sealing function, the intermediate housing 15 and the upper cover 11 are connected by bolt III26, the second O-ring 10 is installed between the intermediate housing 15 and the upper cover 11 to perform a sealing and noise reduction function, the intermediate housing 15 and the rack housing 1 are connected by bolt II25, the third O-ring 17 is installed between the intermediate housing 15 and the rack housing 1 to perform a sealing and noise reduction function, and the fourth O-ring 21 is installed between the rack pressure block 20 and the rack housing 1 to perform a sealing and noise reduction function.

[0029] With the above structural setup, the gaps between different structures are filled by O-rings No. 1 (3), No. 2 (10), and No. 3 (17), preventing dust and other debris from entering the equipment through the gaps. At the same time, it blocks the noise generated by the internal equipment during operation, thus achieving the function of sealing and noise reduction.

[0030] The connecting rod assembly includes a bellows 33. The larger end of the bellows 33 is fixedly installed on the outside of the rack housing 1 by a large clamp 32. The smaller end of the bellows 33 is fixedly installed on the inner tie rod 35 by a small clamp 34. The inner tie rod 35 is connected to the rack 18 by a thread, and the inner tie rod 35 is connected to the outer tie rod 37 by a tie rod nut 36.

[0031] With the above-mentioned structural configuration, the rack 18 pushes the inner tie rod 35 and the outer tie rod 37 to move; the outer tie rod 37 drives the steering knuckle b, thereby achieving the steering purpose.

[0032] Working principle: The electronic control unit 2 transmits torque to the worm gear I 7 through the elastic element 4. The rotation of the worm gear 7 drives the worm wheel 9 to rotate, which in turn drives the gear shaft 9 to rotate. The gear shaft 9 drives the rack 18 to move in a linear motion. The rack 18 drives the inner tie rod 35 and the outer tie rod 37. The outer tie rod 37 drives the steering knuckle b, thereby achieving the steering purpose. In an emergency, if the mechanical structure fails, the electronic control unit 2 on the other side transmits torque to the worm gear II 29 through the elastic element 4. The rotation of the worm gear II 29 drives the worm wheel 9 to rotate, which in turn drives the gear shaft 12 to rotate. The gear shaft 12 drives the rack 18 to move in a linear motion, which in turn drives the inner tie rod 35 and the outer tie rod 37. The outer tie rod 37 drives the steering knuckle b, thereby achieving the purpose of continuing to assist steering in an emergency.

[0033] Those skilled in the art should understand that this invention is an improved device for a steer-by-wire single pinion steering actuator with a mechanically redundant structure. Its innovation lies in the coordinated layout and specific structural relationships of the components, rather than the implementation method of the basic functions. The connections between the existing parts, the operating parameters, and the control logic involved are all common knowledge and conventional design choices in the field. Technical personnel can determine the appropriate specific implementation method by conducting limited experiments or referring to technical manuals, or by having qualified professional manufacturers standardize and guide the operation according to mature industry standards, based on the overall design requirements of the equipment. No creative labor is required.

[0034] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Furthermore, since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail here.

[0035] All standard parts used in this invention can be purchased from the market, and irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art, which will not be described in detail here.

Claims

1. A steer-by-wire single-pinion steering actuator with a mechanical redundancy structure, characterized in that: The device includes a rack housing (1), a middle housing (15) symmetrically mounted on the top of the rack housing (1), an electronic control unit (2) fixedly connected to the side of the middle housing (15) via a reduction assembly, a speed reduction assembly meshing with the reduction assembly is provided inside the middle housing (15), an adjustment assembly for adjusting the clearance is provided inside the rack housing (1), a sealing assembly is provided at the connection between the rack housing (1) and the middle housing (15), the electronic control unit (2) is connected to the sensor wiring harness assembly (28) via bolt V (27), and a connecting rod assembly is provided on the outside of the rack housing (1).

2. The steerable drive single pinion steering actuator with mechanical redundancy structure according to claim 1, characterized in that: The deceleration assembly includes an elastic element (4). The electronic control unit (2) is connected to the half coupling (5) through the elastic element (4). The half coupling (5) is press-fitted onto the first worm (7). The interior of the intermediate housing (15) is sequentially equipped with a four-point contact ball bearing (6) and a deep groove ball bearing (8). The two ends of the first worm (7) are respectively installed inside the four-point contact ball bearing (6) and the deep groove ball bearing (8).

3. The steer-by-wire single pinion steering actuator with mechanical redundancy structure according to claim 1, characterized in that: The speed reduction assembly includes a gear shaft (12). The gear shaft (12) is vertically rotatably mounted inside the intermediate housing (15). A worm wheel (9) that meshes with the first worm (7) is fixedly mounted on the gear shaft (12). A sensor rotor (13) and a sensor body (14) are fixedly mounted on the gear shaft (12). A four-point contact ball bearing (16) and a needle roller bearing (19) are fixedly mounted at one end of the gear shaft (12). The four-point contact ball bearing (16) is press-fitted into the intermediate housing (15). The needle roller bearing (19) is press-fitted into the rack housing (1). A rack (18) that meshes with the gear shaft (12) is provided inside the rack housing (1).

4. A steer-by-wire single pinion steering actuator with mechanical redundancy structure according to claim 1, characterized in that: The gap assembly includes an adjusting stud (22), an internal adjusting stud (22) of the rack housing (1), and a rack pressure block (20) which is fixedly installed inside the rack housing (1) by cooperating with the adjusting stud (22) through a locking nut (23).

5. A steer-by-wire single pinion steering actuator with mechanical redundancy structure according to claim 1, characterized in that: The sealing assembly includes a first O-ring (3), the electronic control unit (2) and the intermediate housing (15) are connected by bolt I (24), the first O-ring (3) is installed between the intermediate housing (15) and the electronic control unit (2) for sealing, the intermediate housing (15) and the top cover (11) are connected by bolt III (26), the second O-ring (10) is installed between the intermediate housing (15) and the top cover (11) for sealing and noise reduction, the intermediate housing (15) and the rack housing (1) are connected by bolt II (25), the third O-ring (17) is installed between the intermediate housing (15) and the rack housing (1) for sealing and noise reduction, and the fourth O-ring (21) is installed between the rack pressure block (20) and the rack housing (1) for sealing and noise reduction.

6. A steer-by-wire single pinion steering actuator with mechanical redundancy structure according to claim 1, characterized in that: The connecting rod assembly includes a bellows (33), the larger end of which is fixedly installed on the outside of the rack housing (1) by a large clamp (32), and the smaller end of the bellows (33) is fixedly installed on the inner tie rod (35) by a small clamp (36). The inner tie rod (35) is connected to the rack (18) by a thread, and the inner tie rod (35) is connected to the outer tie rod (37) by a tie rod nut (36).

Images