Self-adaptive transmission structure of electric power steering gear and steering pull rod

Abstract

The invention belongs to the technical field of light passenger car manufacturing and assembling, and particularly relates to a self-adaptive transmission structure of an electric power steering gear and a steering pull rod, which comprises a steering column, an electric power steering gear body, a power motor, a speed reducing mechanism, the steering pull rod and a self-adaptive adjusting assembly. According to the self-adaptive power-assisted steering system, the stress and displacement change of the steering pull rod is detected through the sensor, and the controller adjusts the power-assisted motor accordingly to realize self-adaptive power-assisted steering. The speed reducing mechanism adopts multi-stage gear transmission, the length of a steering pull rod is adjustable, and the angle of a steering column is adjustable; the lubricating system automatically lubricates key parts, the controller has multiple steering modes and is in linkage with the air suspension, steering comfort, transmission efficiency and system reliability are improved, cooperative work of a chassis system is achieved, and the advantages of being convenient to install and maintain, high in compatibility and the like are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of light commercial vehicle manufacturing, and in particular to an adaptive transmission structure of an electric power steering device and a steering rod. Background Art

[0002] With the development of the global economy, the market demand for efficient and versatile transportation vehicles is increasing. Light commercial vehicles, capable of carrying both passengers and cargo, with excellent fuel efficiency and flexibility, have found widespread application in urban logistics, business travel, and tourist transport. From their initial simple mechanical structure to today's advanced powertrains, intelligent driver assistance systems, comfortable interiors, and user-friendly designs, each generation strives to achieve a perfect combination of quality and performance. In the development of light commercial vehicle steering systems, traditional electric power steering (EPS) often presents numerous challenges that require resolution. First, the transmission matching between the EPS and the steering tie rod in traditional structures is poor, making it difficult to achieve precise and adaptive transmission adjustment under varying road conditions and vehicle speeds. This results in drivers experiencing a lack of consistently stable and comfortable steering feel. Second, existing transmission structures, due to suboptimal component connections, are prone to wear over time, which not only affects steering efficiency but also poses safety risks. Furthermore, the traditional structure suffers from poor interoperability with other electronic control systems within the vehicle chassis, preventing it from fully leveraging the advantages of electronic control and intelligentization, significantly limiting improvements in vehicle handling stability and comfort. To address these shortcomings, the present invention proposes an adaptive transmission structure for an electric power steering system and steering rod. By optimizing component composition, connection relationships, and positional layout, this structure achieves adaptive transmission adjustment of the steering system, improving the vehicle's overall handling performance and driving comfort. Summary of the Invention

[0003] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid blurring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0004] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0005] An adaptive transmission structure of an electric power steering gear and a steering rod, comprising a steering column, an electric power steering gear body, a power motor, a reduction mechanism, a steering rod, and an adaptive adjustment component;

[0006] The electric power steering body is fixedly mounted on the vehicle frame, one end of the steering column is connected to the input shaft of the electric power steering body via a spline, and the other end is used to connect to the steering wheel;

[0007] The power-assisting motor is fixedly mounted on the side of the electric power steering body through a motor bracket a, and the output shaft of the power-assisting motor is transmission-connected to the input end of the reduction mechanism, and the output end of the reduction mechanism is meshed with the transmission gear inside the electric power steering body;

[0008] One end of the steering rod is connected to the output end of the electric power steering body through a universal joint, and the other end is connected to the steering knuckle through a ball pin a;

[0009] The adaptive adjustment component includes a sensor and a controller. The sensor is installed on the steering rod and is used to detect the force and displacement changes of the steering rod. The controller is fixedly installed on the outer shell of the electric power steering body, and the controller is electrically connected to the power motor and sensor through a wiring harness. The controller is electrically connected to the vehicle controller of the vehicle.

[0010] As a preferred solution of the adaptive transmission structure of the electric power steering device and the steering rod described in the present invention, wherein: the sensor includes a torque sensor a and an angle sensor b, the torque sensor a is mounted on the outside of the steering rod, and is used to detect the magnitude of the torque applied to the steering rod, the angle sensor b is installed at the connection between the steering rod and the universal joint, and is used to detect the rotation angle of the steering rod, and the torque sensor a and the angle sensor b are both electrically connected to the controller.

[0011] As a preferred solution of the adaptive transmission structure of the electric power steering and steering rod described in the present invention, the deceleration mechanism is a reduction gearbox, and at least three reduction gears meshing in sequence are arranged inside the reduction gearbox, and the output shaft of the power-assisted motor is decelerated through multiple reduction gears and is used to drive the transmission gear inside the electric power steering body to rotate.

[0012] As a preferred solution of the adaptive transmission structure of the electric power steering device and the steering rod described in the present invention, the steering rod includes an inner rod b and an outer rod c, one end of the inner rod b is connected to the output end of the electric power steering device body through a thread, and the other end is threadedly connected to one end of the outer rod c through an adjusting sleeve d, the other end of the outer rod c is connected to the steering knuckle through a ball pin a, and a locking nut is provided on the adjusting sleeve d.

[0013] As a preferred solution of the adaptive transmission structure of the electric power steering device and the steering rod described in the present invention, an angle adjustment mechanism is provided between the steering column and the input shaft of the electric power steering device body, and the angle adjustment mechanism includes an adjustment bracket a and an adjustment bolt b. The adjustment bracket a is fixedly mounted on the outer shell of the electric power steering device body, and the steering column is mounted on the adjustment bracket a through a bearing. The adjustment bolt b passes through the adjustment bracket a and abuts against the outer wall of the steering column for adjusting the inclination angle of the steering column.

[0014] As a preferred solution of the adaptive transmission structure of the electric power steering and steering rod described in the present invention, the power-assisted motor is a brushless DC motor, and the output shaft of the power-assisted motor is connected to the input end of the reduction mechanism through a synchronous belt transmission, and tensioning pulleys are provided on both sides of the synchronous belt.

[0015] As a preferred solution of the adaptive transmission structure of the electric power steering device and steering rod described in the present invention, it also includes a lubrication system, which includes an oil storage tank, an oil pump a and an oil pipe b. The oil storage tank and oil pump a are fixedly installed on the vehicle frame. The input end of the oil pump a is connected to the oil storage tank through the oil pipe b, and the output end is respectively connected to the deceleration mechanism and the universal joint through the oil pipe b. The controller is electrically connected to the oil pump a for controlling the start and stop of the oil pump a.

[0016] As a preferred solution of the adaptive transmission structure of the electric power steering and the steering rod described in the present invention, it is characterized in that: the torque sensor a is a strain gauge torque sensor, its elastic shaft is coaxially arranged with the steering rod, and the two ends of the elastic shaft are respectively connected to the two ends of the steering rod through a coupling, and the angle sensor b is an absolute encoder, and its rotor shaft is coaxially arranged with the rotating axis of the steering rod.

[0017] As a preferred solution of the adaptive transmission structure of the electric power steering device and steering rod described in the present invention, wherein: a signal processing module and a control algorithm module are arranged inside the controller, the signal processing module is used to receive the electrical signal sent by the sensor and perform filtering and amplification processing, the control algorithm module is used to calculate the target speed and target torque of the power-assisted motor based on the processed electrical signal, and generate a control signal to send to the power-assisted motor, and the control algorithm module stores a plurality of steering assist modes, including comfort mode, sports mode and energy-saving mode.

[0018] As a preferred solution of the adaptive transmission structure of the electric power steering and steering rod described in the present invention, the adaptive transmission structure of the electric power steering and steering rod is also electrically connected to the vehicle's air suspension system, and the controller is connected to the air suspension controller via a CAN bus.

[0019] The beneficial effects of the present invention are:

[0020] 1. A sensor detects changes in steering rod force and displacement, and the controller adjusts the power-assist motor accordingly, achieving adaptive steering assistance. The reduction mechanism utilizes a multi-stage gear drive, and the steering rod and steering column are adjustable in length and angle.

[0021] 2. The lubrication system automatically lubricates key components. The controller includes multiple steering modes and is linked with the air suspension, which improves steering comfort, transmission efficiency and system reliability, and enables the coordinated operation of the chassis system. It has the advantages of easy installation and maintenance and strong compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort. Among them:

[0023] Figure 1 It is a structural schematic diagram of the present invention;

[0024] Figure 2 It is a structural schematic diagram of the steering column and other components of the present invention;

[0025] Figure 3 For the present invention Figure 2 Schematic diagram of the structure of area A;

[0026] Figure 4 For the present invention Figure 2 Schematic diagram of the structure of area B in the middle;

[0027] Figure 5 For the present invention Figure 2 Schematic diagram of the structure of the middle C area. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] Next, the present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing the embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of protection of the present invention. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0031] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0032] See also Figure 1-Figure 5 , which shows a schematic diagram of the structure of an adaptive transmission structure embodiment of an electric power steering device and a steering rod of the present invention, please refer to Figure 1-Figure 5 , and gives a detailed introduction to the adaptive transmission structure of the electric power steering and steering rod.

[0033] The adaptive transmission structure of the electric power steering and the steering rod includes a steering column 100, an electric power steering body 101, a power motor 102, a speed reduction mechanism 103, a steering rod 104 and an adaptive adjustment component 105;

[0034] The electric power steering body 101 is fixedly mounted on the vehicle frame 200 , one end of the steering column 100 is connected to the input shaft of the electric power steering body 101 via a spline, and the other end is used to connect to the steering wheel;

[0035] The power-assisting motor 102 is fixedly mounted on the side of the electric power steering body 101 via a motor bracket 102a, and the output shaft of the power-assisting motor 102 is transmission-connected to the input end of the reduction mechanism 103, and the output end of the reduction mechanism 103 is meshed with the transmission gear inside the electric power steering body 101;

[0036] One end of the steering rod 104 is connected to the output end of the electric power steering body 101 through a universal joint 108, and the other end is connected to the steering knuckle 201 through a ball stud 104a;

[0037] The adaptive adjustment component 105 includes a sensor 106 and a controller 107. The sensor 106 is installed on the steering rod 104 and is used to detect the force and displacement changes of the steering rod 104. The controller 107 is fixedly installed on the outer shell of the electric power steering body 101, and the controller 107 is electrically connected to the power motor 102 and the sensor 106 through a wiring harness. The controller 107 is electrically connected to the vehicle controller of the vehicle.

[0038] The present invention realizes adaptive transmission between the electric power steering and the steering rod by setting a specific connection relationship and position layout of the steering column 100, the electric power steering body 101, the power motor 102, the reduction mechanism 103, the steering rod 104 and the adaptive adjustment component 105. The spline connection between the steering column 100 and the input shaft of the electric power steering body 101 ensures the stable transmission of the steering force of the steering wheel; the power motor 102 engages with the transmission gear through the reduction mechanism 103, providing a reliable source of power for steering; the steering rod 104 is connected to the electric power steering body 101 and the steering knuckle 201 through the universal joint 108 and the ball pin 104a respectively, ensuring the flexible transmission of the steering action; the sensor 106 in the adaptive adjustment component 105 detects the force and displacement of the steering rod 104 in real time, and the controller 107 accurately controls the power motor 102, so that the steering system can automatically adjust the power assist according to the actual driving conditions, thereby improving the steering accuracy and the driver's operating feel, while realizing information interaction with the vehicle controller, providing support for the vehicle's electronic control.

[0039] Furthermore, the sensor 106 includes a torque sensor 106a and an angle sensor 106b. The torque sensor 106a is mounted on the outside of the steering rod 104 and is used to detect the torque applied to the steering rod 104. The angle sensor 106b is installed at the connection between the steering rod 104 and the universal joint 108 and is used to detect the rotation angle of the steering rod 104. Both the torque sensor 106a and the angle sensor 106b are electrically connected to the controller 107. The torque sensor 106a and the angle sensor 106b accurately detect the torque applied to the steering rod 104 and the rotation angle, respectively. The torque sensor 106a can sense changes in the driver's steering force in real time, while the angle sensor 106b can accurately obtain steering angle information. These two sensors transmit the detected signals to the controller 107. Based on these signals, the controller 107 can more accurately calculate the required steering force amount and direction, achieving real-time adaptive adjustment of the steering force, allowing the steering system to provide appropriate steering force in different driving scenarios, further improving steering comfort and safety.

[0040] Furthermore, the deceleration mechanism 103 is a deceleration gearbox, which is internally provided with at least three deceleration gears meshing in sequence, and the output shaft of the power-assisting motor 102 is decelerated by multiple deceleration gears and is used to drive the transmission gear inside the electric power steering body 101 to rotate. For example, the deceleration mechanism 103 can adopt a three-stage gear transmission structure of a first gear, a second gear and a third gear. The first gear on the output shaft of the power-assisting motor 102 is meshed with the second gear, and then the third gear is driven to mesh with the transmission gear through the transmission shaft. This multi-stage deceleration transmission method can convert the high speed and low torque of the power-assisting motor 102 into a low speed and high torque suitable for the steering system, which not only improves the transmission efficiency, but also reduces the workload of the power-assisting motor 102. At the same time, the multi-stage gear transmission can make the transmission smoother, reduce vibration and noise during the transmission process, and improve the working reliability and comfort of the steering system.

[0041] Furthermore, the steering rod 104 includes an inner rod 104b and an outer rod 104c, one end of the inner rod 104b is connected to the output end of the electric power steering body 101 through a thread, and the other end is threadedly connected to one end of the outer rod 104c through an adjusting sleeve 104d, the other end of the outer rod 104c is connected to the steering knuckle 201 through a ball pin 104a, and a locking nut is provided on the adjusting sleeve 104d. This structural design allows the length of the steering rod 104 to be adjusted according to actual installation requirements and vehicle positioning parameters. By rotating the adjusting sleeve 104d, the relative position of the inner rod 104b and the outer rod 104c is changed, thereby adjusting parameters such as the toe value of the steering system to ensure the steering performance and driving stability of the vehicle. The locking nut can fix the adjusting sleeve 104d after the adjustment is completed to prevent the length of the steering rod 104 from changing during vehicle driving, thereby ensuring the reliability of the steering system.

[0042] Furthermore, an angle adjustment mechanism 109 is provided between the steering column 100 and the input shaft of the electric power steering body 101. The angle adjustment mechanism 109 includes an adjustment bracket 109a and an adjustment bolt 109b. The adjustment bracket 109a is fixedly mounted on the housing of the electric power steering body 101. The steering column 100 is mounted on the adjustment bracket 109a through a bearing. The adjustment bolt 109b passes through the adjustment bracket 109a and abuts against the outer wall of the steering column 100 to adjust the inclination of the steering column 100. The driver can adjust the tilt angle of the steering column 100 according to his height and driving habits by adjusting the bracket 109a and the adjusting bolt 109b. When adjusting, loosen the adjusting bolt 109b, rotate the steering column 100 to a suitable angle, and then tighten the adjusting bolt 109b to fix the steering column 100 on the adjusting bracket 109a. This structural design improves driving comfort, enables the driver to find a steering operating posture that suits him better, reduces driving fatigue, and also adapts to the usage needs of different drivers.

[0043] Furthermore, the power-assisting motor 102 is a brushless DC motor, and the output shaft of the power-assisting motor 102 is connected to the input end of the reduction mechanism 103 through a synchronous belt transmission, and tensioning pulleys are provided on both sides of the synchronous belt; the brushless DC motor has the advantages of high efficiency, easy maintenance, and long life. The output shaft of the power-assisting motor 102 is connected to the input end of the reduction mechanism 103 through a synchronous belt 102b transmission, and a tensioning pulley is provided to maintain the tension of the synchronous belt 102b; the synchronous belt transmission has the characteristics of smooth transmission, low noise, and no need for lubrication, which can ensure that the power of the power-assisting motor 102 is smoothly transmitted to the reduction mechanism 103. At the same time, the setting of the tensioning pulley avoids the slipping of the synchronous belt 102b due to relaxation during use, thereby improving the reliability and stability of the transmission and ensuring the continuous and stable output of the steering assist.

[0044] Furthermore, it also includes a lubrication system 110, which includes an oil tank, an oil pump 110a and an oil pipe 110b. The oil tank and the oil pump 110a are fixedly mounted on the frame 200. The input end of the oil pump 110a is connected to the oil tank through the oil pipe 110b, and the output end is connected to the speed reduction mechanism 103 and the universal joint 108 through the oil pipe 110b. The controller 107 is electrically connected to the oil pump 110a for controlling the start and stop of the oil pump 110a. Through the cooperation of the oil storage tank, oil pump 110a and oil pipe 110b, lubrication can be automatically provided to key parts such as the reduction mechanism 103 and the universal joint 108; the controller 107 controls the start and stop of the oil pump 110a according to the system working status detected by the sensor 106, and supplies oil in time when the system needs lubrication, reducing friction and wear between components and extending the service life of the steering system. At the same time, good lubrication also reduces noise and heat generation during component operation, thereby improving the working reliability and comfort of the steering system.

[0045] Furthermore, the torque sensor 106a utilizes a strain gauge torque sensor. Its elastic shaft is coaxially arranged with the steering rod 104 and connected to both ends of the steering rod 104 via a coupling. This allows for precise detection of changes in torque applied to the steering rod 104, boasting high measurement accuracy and rapid response. The angle sensor 106b is an absolute encoder with a rotor shaft coaxially arranged with the rotation axis of the steering rod 104. This encoder accurately measures the rotation angle of the steering rod 104 in real time, is unaffected by power outages, and provides accurate absolute angular position information. The combination of these two sensors provides the controller 107 with more precise steering status data, enabling the controller 107 to more accurately control the power-assist motor 102 and precisely adjust the steering assist.

[0046] Furthermore, the adaptive transmission structure of the electric power steering and steering rod is also electrically connected to the vehicle's air suspension system. The controller 107 is connected to the air suspension controller via a CAN bus. The signal processing module within controller 107 filters and amplifies the electrical signal sent by sensor 106, removing interference noise and improving signal stability and reliability. The control algorithm module calculates the target speed and torque of the power-assist motor 102 based on the processed signal and generates a control signal. Multiple steering assist modes, such as comfort mode, sport mode, and energy-saving mode, are stored. Drivers can select different modes based on their driving preferences and needs. Controller 107 adjusts the assist characteristics based on the selected mode, allowing the steering system to exhibit different steering feel in different modes, meeting the needs of different driving scenarios and drivers, and improving the vehicle's driving pleasure and adaptability.

[0047] Furthermore, the adaptive transmission structure of the electric power steering and steering rod is linked to the vehicle's air suspension system via a CAN bus connection between controller 107 and the air suspension controller. When the vehicle is traveling on uneven roads, the air suspension controller adjusts the vehicle body height and suspension damping, and transmits a signal to controller 107. Controller 107 then adjusts the power assist provided by power-assisted motor 102 and the steering feel based on the signal. For example, when the vehicle body height increases or the suspension damping increases, the steering assist is appropriately increased to make steering easier; when the vehicle body height decreases or the suspension damping decreases, the steering assist is appropriately reduced to improve steering feel and handling. This linked control enables the coordinated operation of the chassis systems, further enhancing the vehicle's handling stability and ride comfort under various road conditions, and embodying the advantages of the vehicle's electronic control and intelligentization.

[0048] Furthermore, the innovative features of this solution are described.

[0049] 1. Precise sensing and dynamic control of adaptive adjustment components

[0050] Structural Design: A torque sensor (strain gauge) and an angle sensor (absolute encoder) are integrated into the steering rod to monitor torque changes (range: 0-50 N·m) and rotation angle (accuracy: ±0.5°) in real time. The sensors are electrically connected to the controller, forming a closed "detection-calculation-adjustment" loop.

[0051] Working Principle: After receiving sensor signals, the controller filters and amplifies them through the signal processing module. The control algorithm module then calculates the target speed and torque of the power-assisted motor (response delay ≤ 10ms). For example, when the vehicle is turning at low speed, the sensor detects an increase in torque, and the controller automatically increases the power-assisted motor output, reducing steering effort by 30%. At high speeds, the power assist is reduced to improve road feel.

[0052] Problem Solved: Traditional solutions rely on fixed power assist curves, which are unable to adapt to road conditions (such as potholes) and vehicle speed changes, resulting in inconsistent steering feel. This solution uses real-time sensing to dynamically adjust power assist, improving steering accuracy by 46.7% (see data comparison).

[0053] 2. Optimization of transmission efficiency of three-stage gear reduction mechanism

[0054] Structural Design: The reduction mechanism utilizes a three-stage gear transmission (first gear, second gear, third gear), with a gear module of 2.5mm, a tooth surface hardness of HRC55-60, and a transmission ratio of 1:8.5. The power-assisted motor output shaft is connected to the reduction mechanism input via a synchronous belt (with an automatically adjusted tensioner) to minimize slippage.

[0055] Working Principle: A brushless DC motor (rated power 500W) generates high speed (3000rpm) and low torque, which is converted through three stages of gear reduction to low speed (353rpm) and high torque (12N·m), driving the steering gear's internal transmission gears. This multi-stage transmission minimizes torque fluctuations to ≤5%, making it more stable than conventional single-stage reduction gears (fluctuations of 15%).

[0056] Problem solved: Traditional single-stage reduction gears are prone to transmission shock due to sudden changes in speed. This solution uses multi-stage gear meshing to buffer power, increasing transmission efficiency from 85% to 88% while reducing noise by 3dB (measured 65dB → 62dB).

[0057] 3. Dynamic calibration of adjustable steering rod parameters

[0058] Structural Design: The steering rod consists of an inner and outer tie rods, each with a 1.5mm thread pitch, and an adjustment sleeve. The adjustment sleeve is secured with a lock nut. The adjustment range is ±15mm, and toe-in can be calibrated (to an accuracy of ±0.2°).

[0059] Working Principle: During installation, the relative lengths of the inner and outer tie rods are changed by rotating the adjustment sleeve to adjust the toe-in value to the standard range (e.g., 0±0.5°). If the toe-in value deviates due to component wear after 10,000 kilometers, it can be readjusted without replacing the tie rods.

[0060] Problem Solved: Traditional fixed tie rods can have a toe-in deviation of ±1.5° after 10,000 kilometers of use, leading to uneven tire wear (increasing tire wear by 20%). This solution uses an adjustable structure to control deviation to within ±0.8°, extending tire life by 15%.

[0061] 4. Ergonomic adjustment of steering column angle

[0062] Structural Design: The angle adjustment mechanism consists of an adjustment bracket (welded to the steering gear housing) and an adjustment bolt. The steering column is mounted on the bracket via a bearing and can rotate ±15° around the bearing center. Tighten the adjustment bolt to a torque of 15-20 N·m to ensure it is securely fixed.

[0063] How it works: After loosening the adjustment bolt, the driver manually turns the steering column to the desired angle (e.g., 30° for a 175cm tall driver), then tightens the bolt to secure. The adjustment process requires no tools and takes less than 1.5 minutes.

[0064] Problem Solved: Traditional fixed-angle steering columns are only suitable for some drivers, and prolonged driving can easily lead to shoulder fatigue (increasing muscle electrical signal strength by 30%). This solution, with its adjustable angle design, enables 90% of drivers to find a comfortable position, reducing fatigue by 25%.

[0065] 5. Wear control of intelligent lubrication system

[0066] Structural design: The lubrication system includes an oil tank (capacity 500mL), an oil pump (flow rate 5mL / min) and oil pipes. The oil pump is automatically started and stopped by the controller according to the mileage (every 5000 kilometers) or sensor temperature (>60℃) to supply oil to the reduction mechanism and universal joint.

[0067] Working principle: When the vehicle reaches the set mileage or the component temperature is too high, the controller sends a signal to start the oil pump, and the lubricating oil is sprayed through the oil pipe to the gear meshing and universal joint bearing. The lubrication cycle is 10 seconds and is repeated every 24 hours.

[0068] Problem solved: Traditional manual lubrication is prone to omission or over-lubrication, resulting in a gear wear rate of 0.12mm / 10,000km. This solution's automatic lubrication reduces the wear rate to 0.09mm / 10,000km, extending the life of the reduction mechanism by 30%.

[0069] 6. Multi-mode controller and chassis coordination of air suspension

[0070] Structural design: The controller has built-in signal processing module and control algorithm module, stores three modes: comfort, sport, and energy saving, and communicates with the air suspension controller via the CAN bus (transmission rate 500kbps).

[0071] Working principle: Mode switching: The driver selects the mode by pressing a button, and the controller adjusts the power assist characteristics within 180ms (such as power assist gain +15% in comfort mode, road feel feedback +20% in sports mode).

[0072] Linked with air suspension: When the air suspension detects road bumps (such as amplitude > 50mm), the controller automatically increases the steering assist by 10% to reduce steering wheel shaking; when cornering at high speed, the air suspension lowers the vehicle body height by 20mm, and the controller simultaneously reduces the assist by 15% to improve handling stability.

[0073] Problem solved: The traditional steering system and chassis work independently, with a roll angle of 5° during cornering. This solution's linked control reduces the roll angle to 4.5°, improving handling stability by 10%.

[0074] Specifically, data comparison of relevant tests and actual applications of this solution.

[0075]

[0076]

[0077] Data Description

[0078] Power steering response time: refers to the time from when the steering wheel is turned 5° to when the power steering motor outputs torque. The new solution has a faster response because the sensor sampling frequency is increased from 100Hz to 200Hz.

[0079] Transmission efficiency: Tested under conditions of 500W input power and 10N·m output torque, the three-stage gear transmission reduces meshing losses (traditional single-stage losses are 12%, while the new solution loses 9%).

[0080] Toe adjustment accuracy: measured by a four-wheel aligner. The traditional solution relies on manual hammering and adjustment, while the new solution achieves precise control through thread fine-tuning.

[0081] Wear rate: An ultrasonic thickness gauge is used to detect gear tooth surface wear. The lubrication system reduces gear contact stress by 20%, slowing wear.

[0082] Data Validity Description

[0083] Test conditions:

[0084] Vehicle type: A light passenger vehicle (2.5 tons curb weight, 3.3 meters wheelbase);

[0085] Road conditions: dry asphalt road (roughness index IRI = 2.0 m / km);

[0086] Load: 50% of rated load (1.25 tons);

[0087] Ambient temperature: 25±2℃, humidity 60±5%.

[0088] Test equipment:

[0089] Torque sensor (accuracy ±0.5% FS), angle encoder (resolution 0.1°);

[0090] Transmission efficiency tester (power measurement accuracy ±1%), four-wheel alignment instrument (angle accuracy ±0.05°).

[0091] Test method:

[0092] Each set of data was tested 10 times, outliers with a deviation of more than 5% were eliminated, and the average value was taken;

[0093] The traditional solution is a mainstream light commercial vehicle steering system on the market, and the new solution is an invented prototype (part tolerance is controlled within ±0.05mm).

[0094] Although the present invention has been described above with reference to embodiments, various modifications may be made thereto and equivalent components may be substituted without departing from the scope of the present invention. In particular, as long as there are no structural conflicts, the various features of the embodiments disclosed herein may be combined with each other in any manner, and the omission of an exhaustive description of such combinations in this specification is solely for the sake of space and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An adaptive transmission structure of an electric power steering device and a steering rod, comprising a steering column (100), an electric power steering device body (101), a power motor (102), a speed reduction mechanism (103), a steering rod (104), and an adaptive adjustment component (105). It is characterized by: The electric power steering body (101) is fixedly mounted on a vehicle frame (200); one end of the steering column (100) is connected to the input shaft of the electric power steering body (101) via a spline, and the other end is used for connecting to a steering wheel; The power-assisting motor (102) is fixedly mounted on a side surface of the electric power steering body (101) via a motor bracket (102a), and the output shaft of the power-assisting motor (102) is transmission-connected to the input end of a speed reduction mechanism (103), and the output end of the speed reduction mechanism (103) is meshed with a transmission gear inside the electric power steering body (101); One end of the steering rod (104) is connected to the output end of the electric power steering body (101) via a universal joint (108), and the other end is connected to the steering knuckle (201) via a ball stud (104a); The adaptive adjustment component (105) includes a sensor (106) and a controller (107). The sensor (106) is installed on the steering rod (104) and is used to detect the force and displacement changes of the steering rod (104). The controller (107) is fixedly installed on the housing of the electric power steering body (101), and the controller (107) is electrically connected to the power motor (102) and the sensor (106) through a wiring harness. The controller (107) is electrically connected to the vehicle controller of the vehicle.

2. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The sensor (106) includes a torque sensor (106a) and an angle sensor (106b). The torque sensor (106a) is sleeved on the outside of the steering rod (104) and is used to detect the torque applied to the steering rod (104). The angle sensor (106b) is installed at the connection between the steering rod (104) and the universal joint (108) and is used to detect the rotation angle of the steering rod (104). Both the torque sensor (106a) and the angle sensor (106b) are electrically connected to the controller (107).

3. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The deceleration mechanism (103) is a reduction gearbox, wherein at least three reduction gears meshing in sequence are arranged inside the reduction gearbox, and the output shaft of the power-assisting motor (102) is decelerated by the multiple reduction gears and is used to drive the transmission gear inside the electric power steering body (101) to rotate.

4. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The steering rod (104) comprises an inner rod (104b) and an outer rod (104c); one end of the inner rod (104b) is connected to the output end of the electric power steering body (101) via a thread, and the other end is threadedly connected to one end of the outer rod (104c) via an adjustment sleeve (104d); the other end of the outer rod (104c) is connected to the steering knuckle (201) via a ball pin (104a), and a locking nut is provided on the adjustment sleeve (104d).

5. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: An angle adjustment mechanism (109) is provided between the steering column (100) and the input shaft of the electric power steering body (101). The angle adjustment mechanism (109) comprises an adjustment bracket (109a) and an adjustment bolt (109b). The adjustment bracket (109a) is fixedly mounted on the housing of the electric power steering body (101). The steering column (100) is mounted on the adjustment bracket (109a) via a bearing. The adjustment bolt (109b) passes through the adjustment bracket (109a) and abuts against the outer wall of the steering column (100) to adjust the tilt angle of the steering column (100).

6. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The boost motor (102) is a brushless DC motor, and the output shaft of the boost motor (102) is connected to the input end of the speed reduction mechanism (103) via a synchronous belt transmission, with tensioning wheels provided on both sides of the synchronous belt.

7. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The vehicle also includes a lubrication system (110), the lubrication system (110) including an oil storage tank, an oil pump (110a) and an oil pipe (110b). The oil storage tank and the oil pump (110a) are fixedly mounted on the vehicle frame (200). The input end of the oil pump (110a) is connected to the oil storage tank via the oil pipe (110b), and the output end is respectively connected to the speed reduction mechanism (103) and the universal joint (108) via the oil pipe (110b). The controller (107) is electrically connected to the oil pump (110a) and is used to control the start and stop of the oil pump (110a).

8. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 2, characterized in that: The torque sensor (106a) is a strain gauge torque sensor, the elastic shaft of which is coaxially arranged with the steering rod (104), and the two ends of the elastic shaft are respectively connected to the two ends of the steering rod (104) through a coupling. The angle sensor (106b) is an absolute encoder, and the rotor shaft of which is coaxially arranged with the rotation axis of the steering rod (104).

9. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The controller (107) is internally provided with a signal processing module and a control algorithm module. The signal processing module is used to receive the electrical signal sent by the sensor (106) and perform filtering and amplification processing. The control algorithm module is used to calculate the target speed and target torque of the power-assisting motor (102) based on the processed electrical signal, and generate a control signal to send to the power-assisting motor (102). The control algorithm module stores a plurality of steering assist modes, including a comfort mode, a sports mode, and an energy-saving mode.

10. The adaptive transmission structure of the electric power steering device and the steering rod according to claim 1, characterized in that: The adaptive transmission structure of the electric power steering and the steering rod is also electrically connected to the air suspension system of the vehicle, and the controller (107) is connected to the air suspension controller via a CAN bus.

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