Adjustable swing arm type suspension structure and anti-tipping control method for vehicle

Abstract

The present invention discloses an adjustable swing arm type suspension structure and an anti-tipping control method for a vehicle, belonging to the technical field of new energy light vehicles. Among them, an adjustable swing arm type suspension structure includes a lower swing arm and an upper swing arm. The lower swing arm is of a triangular structure, and the upper swing arm is of a connecting rod structure. The inner sides of the upper swing arm and the lower swing arm are both rotationally connected to the vehicle frame through a horizontally arranged sliding pipe column structure. The outer ends of the upper swing arm and the lower swing arm are both connected to a steering seat through a horizontally arranged ball head structure, forming a quadrilateral swing structure when viewed from the front. An inclination angle adjustment structure is provided at the sliding pipe column on the inner side of the upper swing arm. The inclination angle adjustment mechanism includes a servo cylinder connected to the central axis of the sliding pipe column of the upper swing arm. The two ends of the central axis extend outwards, and a chute cooperating with the central axis is arranged on the vehicle frame. The servo cylinder is used to control the position of the central axis and the upper swing arm at this chute.

Description

Technical Field

[0001] This solution relates to the technical field of new energy lightweight vehicles, and particularly relates to an adjustable swing arm type suspension structure and an anti-tipping control method for a vehicle. Background Art

[0002] At present, there is a tilting suspension vehicle on the market, which is a three-wheeled vehicle with one wheel on the left and one wheel on the right for the front wheels and one wheel for the rear wheel. The two front wheels have a steering function, and the rear wheel has a driving function. With the above structural form, in a complex terrain environment, the passing performance is better and safer than that of a two-wheeled vehicle. Especially when turning, the tire grip is stronger than that of a two-wheeled vehicle, and compared with a four-wheeled motorcycle, the structure is obviously simpler and the cost is lower. It has the characteristics of stable driving and convenient parking, and is particularly suitable for passing through narrow and crowded road conditions in cities.

[0003] In order to improve the control of the vehicle and reduce the occurrence of vehicle overturning, the existing front suspension mechanism of the reverse tricycle type has problems such as complex structure, unreasonable joint connection, large space occupation, and the vehicle is prone to get out of control in extreme situations (such as high-speed driving, high-speed cornering at a large angle, uneven ground or under high load). Summary of the Invention

[0004] The purpose of the present invention is to provide an adjustable swing arm type suspension structure and an anti-tipping control method for a vehicle, so as to optimize the suspension structure, improve the driving stability of the vehicle, and improve its controllability in extreme situations.

[0005] In order to achieve the above purpose, the technical solution of the present invention is as follows:

[0006] An adjustable swing arm type suspension structure includes a lower swing arm and an upper swing arm. The lower swing arm is a triangular structure, and the upper swing arm is a link structure. The inner sides of the upper swing arm and the lower swing arm are both rotationally connected to the vehicle frame through a horizontally arranged sliding pipe column structure. The outer ends of the upper swing arm and the lower swing arm are both connected to a steering seat through a horizontally arranged ball head structure, forming a swing structure in a quadrilateral shape when viewed from the front.

[0007] An inclination angle adjustment mechanism is provided at the sliding pipe column on the inner side of the upper swing arm. The inclination angle adjustment mechanism includes a servo cylinder connected to the central axis of the sliding pipe column of the upper swing arm. The two ends of the central axis extend outward, and a chute cooperating with the central axis is arranged on the vehicle frame. The servo cylinder is used to control the position of the central axis and the upper swing arm at the chute.

[0008] Furthermore, a first link is rotationally connected to the central axis of the sliding pipe column on the inner side of the upper swing arm, and a second link is rotationally connected to the vehicle frame. The rear end of the first link is rotationally connected to the middle part of the second link. The two ends of the servo cylinder are respectively rotationally connected to the vehicle frame and the outer end of the second link.

[0009] Further, a leaf spring is arranged between the lower swing arm and the upper swing arm. The middle part of the leaf spring is connected to the vehicle frame, and the outer end of the leaf spring is connected to the inner side of the steering seat through an upright ball head structure.

[0010] Further, a steering tie rod is arranged on one side of the steering seat. The outer end of the steering tie rod is connected to the steering seat through a horizontally arranged ball head structure, the inner end of the steering tie rod is connected to the middle cross tie rod through a ball head structure, and the middle cross tie rod is connected to the vehicle steering gear.

[0011] Further, the middle cross tie rod is a horizontally arranged U-shaped structure. The middle part of it is connected to the inner side of the steering tie rod through a ball head structure. Vertical ball head structures are arranged at both outer ends of its two sides. Follow-up arms are arranged at the tops of these ball head structures. One of the follow-up arms is connected to the vehicle frame through a ball head structure, and the other follow-up arm is connected to the steering gear.

[0012] Further, the steering tie rod has a length adjustable structure.

[0013] Further, a rotation angle sensor is arranged at the sliding pipe column structure inside the lower swing arm.

[0014] Further, when the quadrilateral swing structure is in the initial state, the connection line of the rotation points at both ends of the upper swing arm, the connection line of the corresponding rotation points of the upper swing arm and the sliding pipe column of the lower swing arm on the vehicle frame, the connection line of the rotation points at both ends of the lower swing arm, and the connection line of the corresponding rotation points of the upper and lower swing arms on the steering seat construct a trapezoidal structure.

[0015] Further, a clamping position adjusting mechanism is arranged at the connection part between the middle part of the leaf spring and the vehicle frame.

[0016] Further, the clamping position adjusting mechanism includes an upper clamping plate and a lower clamping plate. The upper clamping plate and the lower clamping plate clamp the leaf spring. Sliders are arranged on both sides of the upper clamping plate and the lower clamping plate. Sliding grooves matched with the sliders are arranged on the vehicle frame. Structure blocks are arranged at the outer ends of the sliders. A first servo cylinder is arranged on the side of the structure block. The first servo cylinder is used to control the positions of the structure block, the slider, and the upper and lower clamping plates at the leaf spring.

[0017] A vehicle anti-tipping control method is applied to the above adjustable swing arm type suspension structure, and includes:

[0018] Controlling the positions of the upper clamping plate and the lower clamping plate at the leaf spring through the clamping position adjusting mechanism, and setting a plurality of stroke positions according to the distance from the center of the vehicle frame. These stroke position points correspond to A1, A2, A3, A4, and A5;

[0019] The position of the central axis at the upper sliding groove is controlled by the inclination adjustment mechanism, and multiple stroke positions are set according to the distance from the center of the vehicle frame. These stroke position points correspond to B1, B2, B3, and B4.

[0020] In the initial state, the position adjustment mechanism controls the stroke position to point A1, and the inclination adjustment mechanism controls the stroke position to point B4.

[0021] Through the vehicle electronic control unit, the real-time speed value and real-time steering angle value of the current vehicle are obtained; the real-time speed value is converted into a real-time speed reference value in the way of corresponding table values, and the rotation angle value is converted into a rotation angle reference value in the way of corresponding table values. If the product value of the real-time speed reference value and the rotation angle reference value is greater than the set value, the position adjustment mechanism is controlled to a position at or outside A2, and the inclination adjustment mechanism is controlled to a position at or inside B2.

[0022] After the above control, through the rotation angle sensors of the left and right lower sliding pipe columns, the corresponding rotation angle values are obtained, and combined with the feedback value of the vertical angle sensor at the vehicle frame, the real-time roll angle value of the current vehicle is obtained; if the real-time roll angle value is greater than the set value, the position adjustment mechanism on the outer side of the turn is controlled to a position at or outside A3, and the inclination adjustment mechanism on the outer side of the roll is controlled to a position at or inside B3.

[0023] Furthermore, in the initial state, by providing options for the driver including comfort or sport, if the driver selects the comfort option, the original stroke position points are retained; if the driver selects the sport option, the position adjustment mechanism is controlled to a position at or outside A2, and the inclination adjustment mechanism is controlled to a position at or inside B3.

[0024] Adopting this solution, compared with the prior art, it has the following advantages:

[0025] This solution is an adjustable swing arm type suspension structure. The main body forms a swing structure with a quadrilateral shape through the upper swing arm, lower swing arm, steering seat and vehicle frame structure. Specifically, in the initial state, a trapezoidal structure is constructed. This structure is for the suspension of the front two-wheel tricycle structure, which can increase the contact area between the wheels and the ground when the wheels are moving and turning, and control a certain camber angle of the wheels under high load conditions, thereby improving the driving stability of the vehicle and reducing the occurrence of rollover phenomena.

[0026] The upper swing arm and the lower swing arm are both connected to the steering seat through horizontally arranged ball head structures, which have the characteristics of convenient installation and maintenance and flexible and reliable use. For the lower swing arm, the ground clearance can be increased to reduce the occurrence of bottoming.

[0027] The shock-absorbing structure main body of this solution is implemented by a leaf spring. By arranging the leaf spring between the upper swing arm and the lower swing arm, the structural complexity of the suspension can be greatly reduced, making the structure more concise and efficient, reducing the occupation of the vehicle body space by the complex suspension structure, improving the space utilization rate of the vehicle, and reducing the unsprung mass of the suspension, making the suspension simple and efficient, and improving the flexibility and controllability of vehicle driving;

[0028] The leaf spring implements the connection operation to the middle part of the vehicle frame through the clamping position adjustment mechanism, and realizes the independent adjustment of the single-side connection point through the clamping position adjustment mechanism. Therefore, according to the characteristics of the leaf spring itself, the clamping position adjustment mechanism is used to control the stroke and elastic support force of the leaf spring. Therefore, the situation of the load-bearing wheel reducing roll can be controlled, thereby improving the controllability of the vehicle, and in extreme cases, the support force can be increased and the roll situation can be reduced;

[0029] The leaf spring implements the control of the stroke and elastic support force of the leaf spring through the clamping position adjustment mechanism, which can realize the adjustment of the vehicle operation mode, and the adjustment of the suspension softness and hardness degree and the total stroke height. Therefore, the driving pleasure and controllability can be improved;

[0030] By arranging the inclination angle adjustment mechanism at the sliding pipe column of the upper swing arm, the inclination angle of the wheel can be adjusted in extreme cases. Specifically, it is to perform a moderate "toe-out" roll adjustment on the high-load wheel. Therefore, the width of the ground contact point at the lower end of the wheel can be increased, the lateral support force can be increased, and the force on the wheel can be made more directional, improving the stability of the vehicle in extreme cases and reducing the occurrence of roll situations;

[0031] A vehicle anti-tipping control method of this solution mainly uses the clamping position adjustment mechanism and the inclination angle adjustment mechanism to control the leaf spring and the upper swing arm, realizes the control of the support force of the leaf spring and the corresponding vehicle tilt angle, and improves the stability and controllability of the vehicle in extreme cases. Specifically, under the control and coordination of the vehicle electronic control unit ECU, by obtaining the load value, speed value, turning angle value and roll angle value of the vehicle for targeted adjustment and control, and specifically implementing the travel control with differences in driving conditions, the adjustment operation of preventing roll and improving the controllability of the vehicle can be realized. Description of the Drawings

[0032] Figure 1 It is an overall schematic diagram of the suspension structure of the preferred embodiment.

[0033] Figure 2 It is a front view structural schematic diagram of the front wheel suspension.

[0034] Figure 3 It is a structural schematic diagram of a single-side front wheel suspension.

[0035] Figure 4Schematic diagram of the suspension structure for the front wheels.

[0036] Figure 5 Schematic diagram of the adjustment structure for the front wheel suspension.

[0037] Figure 6 Front view structural diagram of the adjustment for the front wheel suspension.

[0038] Figure 7 Schematic diagram of the unilateral suspension structure in the initial state.

[0039] Figure 8 Schematic diagram of the lateral force on the wheel in the camber control and upright state.

[0040] Figure 9 Schematic diagram of the unilateral suspension structure when the wheel is in the high travel state.

[0041] Figure 10 Comparison diagram of the suspension structure in the camber control state.

[0042] Figure 11 Layout diagram of the control stroke position points. Detailed implementation method

[0043] The original intention of this solution is to provide a suspension structure that can be applied to new energy vehicles. This type of vehicle is characterized by its lightweight structure, convenient use, low energy consumption, and meets the basic conditions of green environmental protection. It is particularly suitable for single or double-person use on urban roads and is currently widely used in many countries and regions (such as many European countries). The suspension structure of this solution aims to improve the driving stability of such vehicles, reduce the occurrence of tipping and other situations, achieve better handling performance than traditional vehicles, and realize controllability and stability in extreme driving conditions.

[0044] Reference Figure 1 Some embodiments of this solution are applied to a vehicle, especially a lightweight three-wheeled vehicle, including a left front wheel 12 and a right front wheel 11. The left front wheel 12 and the right front wheel 11 are symmetrically arranged in the main body. The rear wheel 13 is arranged directly behind the vehicle. The left front wheel 12, the right front wheel 11, and the rear wheel 13 rely on the suspension structure and the vehicle frame 10 to form an overall structure. Among them, the left front wheel 12 and the right front wheel 11 implement the load-bearing and steering structures, and the rear wheel 13 implements the load-bearing and driving structures. When applied to new energy vehicles, structures such as the battery of the new energy vehicle can be arranged on the vehicle frame and implemented through the hub motor structure of the rear wheel 13. A steering gear 14 is arranged at the middle position of the vehicle frame 10, and the operator uses it to implement the steering function of the left front wheel 12 and the right front wheel 11.

[0045] Reference Figures 2 to 6, An adjustable swing arm type suspension structure, including a lower swing arm 21 and an upper swing arm 22. The lower swing arm 21 is of a triangular structure, and the upper swing arm 22 is of a connecting rod structure. The inner side of the lower swing arm 21 is rotationally connected to the vehicle frame 10 through a horizontally arranged lower sliding pipe column 211. The inner side of the upper swing arm 22 is rotationally connected to the vehicle frame 10 through a horizontally arranged upper sliding pipe column 221 structure. The outer ends of both the lower swing arm 21 and the upper swing arm 22 are connected to the steering seat 23 through horizontally arranged ball joint structures, forming a swing structure in a quadrilateral shape when viewed from the front.

[0046] To be exact, in the initial state (specifically when the vehicle is properly loaded and on a horizontal road surface, and when the lower swing arm 21 is in a horizontal arrangement state), referring to Figure 6 , with the connecting line S1 between the rotation points at both ends of the upper swing arm 22, the connecting line S2 between the upper sliding pipe column 221 and the lower sliding pipe column 211 at the vehicle frame 10, the connecting line S3 between the rotation points at both ends of the lower swing arm 21, and the connecting line S4 of the steering seat 23 corresponding to the rotation points of the upper swing arm 22 and the lower swing arm 21, these four connecting lines form a trapezoidal structure. Among them, the length of S1 is less than that of S2, and the included angles formed by S4 and S3 and by S2 and S3 are both less than 90°, and the included angle formed by S4 and S3 is greater than the included angle formed by S2 and S3.

[0047] The steering seat 23 is used to install the wheel 26 and other related devices, such as braking components and speed sensors, etc. A steering tie rod 24 is arranged on one side of the steering seat 23. The outer end of the steering tie rod 24 is connected to the steering seat 23 through a horizontally arranged ball joint structure. Through the steering tie rod 24, the steering seat 23 rotates around the outer ball joints of the upper swing arm 22 and the lower swing arm 21 to achieve the turning control of the vehicle. In actual work, the turning angle of the steering seat 23 is controlled and maintained through the steering tie rod 30. The triangular lower swing arm 21 realizes the lateral and longitudinal supporting forces, and the upper swing arm 22 realizes the lateral supporting force. Therefore, the entire steering seat 23 has good structural integrity and flexibility, and can be adapted to the application of lightweight vehicles.

[0048] To improve the vehicle's maneuverability, the downward extension line of the connecting line S4 passes through a position near the center of the contact between the wheel 26 and the ground. Therefore, when the wheel 26 performs a turning operation, the rotation center point thereof matches the continuous S4, thereby greatly reducing the difficulty of vehicle turning. When the wheel 26 turns, the steering mechanism does not need to additionally drive the offset of the vehicle body, which can reduce the load on the steering mechanism, improve its service stability and lifespan, reduce the reverse pulling force on the steering mechanism when the wheel rotates, and reduce the interference between the left and right wheels caused thereby. Therefore, the turning stability of the vehicle can be improved.

[0049] The tie rod 24 has an adjustable length structure. Its main body is a three-section structure, where the middle section is a screw structure and the inner and outer sections are internal thread structures. Therefore, by rotating the middle section, the distance relationship at the inner and outer sections can be adjusted, thereby realizing the adjustment of the length of the tie rod 24. When necessary, fastening nuts are arranged at the inner and outer sections to ensure fastening after adjustment and prevent sliding and other situations after continuous operation. Through the adjustable length structure of the tie rod 24, the restraint angles of the left front wheel 12 and the right front wheel 11 can be realized, ensuring the stability of vehicle driving and realizing the straight-line walking and vehicle return operation after turning.

[0050] The inner end of the tie rod 24 is connected to the middle cross rod 31 through a ball joint structure. The middle cross rod 31 is connected to the steering gear 14 of the vehicle. The middle cross rod 31 is a horizontal U-shaped structure. Its middle part is connected to the inner side of the tie rod 24 through a horizontally arranged ball joint structure. Vertical ball joint structures are arranged at both outer ends on both sides. Follow-up arms 32 are arranged at the top of each ball joint structure. One of the follow-up arms 32 is connected to the vehicle frame 10 through a ball joint structure, and the other follow-up arm 32 is connected to the steering gear 14. When the operator rotates the steering gear 14, it drives the middle cross rod 31 to swing within the rotation range of the two follow-up arms 32 through a link structure, and the left and right tie rods 24 drive the corresponding wheels 26 to perform steering operations. Due to the use of the follow-up arm 31, the middle cross rod 31 and the ball joint structure, when the tie rod 24 drives the wheel 26 to turn, it will not be affected by the up and down height of the wheel suspension, nor will it interfere with each other due to the different suspension heights of the left and right wheels. Therefore, the vehicle has good controllability and realizes precise control in extreme cases.

[0051] A leaf spring 25 is arranged between the lower swing arm 21 and the upper swing arm 22. The leaf spring 25 is a long strip structure. The leaf spring 25 is a composite leaf spring, which is composed of fiber-reinforced composite materials and materials based on polyurethane matrix resin, etc., and is manufactured by a layer-by-layer pasting process, similar to the manufacturing process of carbon fiber components. The material of this leaf spring 25 has excellent corrosion resistance and product life, has more advantages than traditional coil springs, and has a lighter weight, occupying less space in the wheel arch, which is beneficial to the layout of the interior space of the vehicle. At the same time, the durability advantage of the leaf spring 25 is very significant in the vehicle suspension system.

[0052] The middle part of the leaf spring 25 is connected to the vehicle frame 10. The outer end of the leaf spring 25 is connected to the inner side of the steering seat 23 through an upright ball joint structure. The rotation center point of this ball joint structure is near the connecting line S4. Therefore, when the leaf spring 25 bears the load of the wheel, it can maintain a straight alignment state with the contact between the bottom of the wheel and the ground and will not twist. Therefore, the balance of load bearing can be realized during turning, bearing and various road conditions, and the interference caused by the load bearing of the leaf spring 25 can be reduced.

[0053] This solution uses a vertical ball head structure to connect the leaf spring 25 and the bogie 23. The ball head link in the ball head can form a slightly left - right deflection structure, which can accommodate the distance difference generated by the torsion of the leaf spring 25 during the up - and - down movement of the wheel 26, making the entire leaf spring 25 bear more smoothly and greatly reducing the complex load - bearing disc structure required by the traditional leaf spring connection structure.

[0054] At the same time, in this solution, the leaf spring 25 is directly connected to the steering seat 23 through a vertical ball head structure, rather than being connected to the lower swing arm or the upper swing arm. Therefore, through such a structure, the load on the ball head at the upper swing arm 22 or the lower swing arm 21 can be reduced, making it more flexible and efficient, and improving the stability and service life of the entire suspension structure.

[0055] Looking at the structure of one side of the wheel, a trapezoidal structure is constructed by four connecting lines S1, S2, S3, and S4. This suspension structure is a type of double - wishbone suspension, but it is not a traditional double - wishbone suspension structure. The traditional double - wishbone suspension is designed for vehicles to ensure that when the wheel moves up and down, the contact surface between its tire and the ground is always flat and has the largest contact area. Therefore, when the wheel is in the upward or downward state, the wheel always maintains a large grip on the ground, thereby improving the vehicle's handling performance. So, the traditional double - wishbone is usually a parallelogram structure, and the upper and lower swing arms have a structure similar to equal - length swinging.

[0056] The above - mentioned traditional double - wishbone structure is usually applied to cars, especially high - performance vehicles. Since its front wheels have a relatively wide size and its ground contact width exceeds 20 cm, such a design can fully ensure its contact area. However, in this solution, it is applied to the design of lightweight vehicles, and its front wheels usually have a structure similar to that of a motorcycle wheel, that is, the outer edge surface of the wheel is similar to an arc structure. If a straight - up - and - down structure is adopted, when turning at a large angle, the tire surface of the wheel is likely to be distorted, resulting in a decrease in the support force, a reduction in the handling performance, and an acceleration of the wear of the wheel. As Figure 8 shown, when the wheel of this type of vehicle is in the vertical state and receives a lateral thrust, the rubber parts of the wheel are extremely likely to be distorted, thereby reducing the vehicle's handling performance. However, after implementing the camber control, the wheel supports the force obliquely, and its support force and the lateral thrust can offset each other to a certain extent. Therefore, the vehicle's handling performance can be improved, and the occurrence of roll can be reduced.

[0057] Reference Figure 7 Figure 8 Figure 9 adopts a layout where the length of S1 (corresponding to the upper swing arm 22) is less than the length of S3 (corresponding to the lower swing arm 21) in the trapezoidal structure. In its initial state, due to the trapezoidal structure, it can ensure that the wheel 26 is in a state perpendicular to the road surface (as Figure 9as shown); when it is in the upward state, usually in the case of high load and large-angle turning, this structure can ensure a slight roll of the wheel (as Figure 9 shown), so it can have better supporting force than the wheel with a vertical layout structure.

[0058] This solution is dedicated to a lightweight, efficient and stable suspension structure to achieve the stability and controllability of driving, and to reduce the roll in extreme cases. Specifically, this solution adopts a specific structure of the upper swing arm 22, the lower swing arm 21, the steering seat 23 and the leaf spring 25, etc., realizing the simplification of the structure, reducing the space occupation, and making the vehicle have excellent controllability and stability;

[0059] In order to better improve the stability of the vehicle and achieve the controllability in extreme cases, this solution also has a clamping and adjusting mechanism 4 arranged at the connection between the middle of the leaf spring 25 and the vehicle frame 10, and an inclination adjusting mechanism 5 arranged at the upper sliding pipe column 221 on the inner side of the upper swing arm 22.

[0060] The clamping and adjusting mechanism 4 is used for clamping and adjusting the leaf spring 25. Its upper clamping plate 41 and lower clamping plate, the upper clamping plate 41 and the lower clamping plate arrange the leaf spring 25 in a clamped state. The upper clamping plate 41 and the lower clamping plate are symmetric structures up and down. The contact surfaces at both ends with the leaf spring 25 have arc chamfer structures, which can reduce the wear of the leaf spring 25 at its edge and make the force more balanced. The upper clamping plate 41 and the lower clamping plate can have a self-lubricating coating at the contact surface with the leaf spring 25. This coating can be a Teflon material to reduce the frictional resistance of the upper clamping plate 41 and the lower clamping plate during the displacement movement on the surface of the leaf spring 25, making the adjustment position operation more convenient;

[0061] The upper clamping plate 41 and the lower clamping plate extend outwards with sliders 43 on both sides. The vehicle frame 10 is provided with a chute 44 that cooperates with the sliders 43. The vehicle frame 10 at this chute 44 also plays a role in restricting the leaf spring 25 back and forth. Therefore, here, the leaf spring 25 can swing up and down in the vertical direction, but cannot displace back and forth in the horizontal direction. A structural block 45 is arranged at the outer end of the slider 43, and a first servo cylinder 46 is arranged on the side of the structural block 45. The rear end of the first servo cylinder 46 is connected to the vehicle frame 10. Under the control of the controller, the first servo cylinder 46 can be used to control the structural block 45, the slider 43 and the upper and lower clamping plates, and the positional relationship with the leaf spring 25 within the range of the chute 44.

[0062] Regarding the leaf spring 25, generally speaking, it is a long strip-shaped structure. Its middle part is fixedly installed on the vehicle frame 10, and both ends are connected to the steering seat 23 through ball joints, playing an elastic support role. That is, the load of the wheel 26 is transmitted to the vehicle frame 10 through the leaf spring 25, or in other words, the self-weight and load of the vehicle are transmitted to the vehicle 26 through the leaf spring 25. Therefore, when the vehicle is loaded, moving, turning, or on an uneven road surface, the outer ends of the leaf spring 25 will all swing up and down;

[0063] Although according to the design of the leaf spring 25, its outer end can be designed to have a reduced thickness, for the sake of simplifying the description, the elastic force of this leaf spring 25 corresponds to its length. Therefore, under the same load, the longer the length, the greater the swing angle of its outer end, and vice versa, the shorter the length, the smaller the swing angle of its outer end.

[0064] This solution controls the positional relationship between the upper clamping plate 41 and the lower clamping plate through the first servo cylinder 46, and controls the positional relationship of independent control through the left and right wheels, realizing the elastic control of the leaf spring 25 of the left and right wheels of the vehicle, and thus realizing precise anti-roll control.

[0065] The inclination angle adjusting mechanism 5 is used to adjust the horizontal position of the upper sliding pipe column 221 on the inner side of the upper swing arm 22. Specifically, the inclination angle adjusting mechanism 5 includes a first connecting rod 51 rotatably connected to the central axis of the upper sliding pipe column 221. A second connecting rod 52 is rotatably arranged on the vehicle frame 10, and the rear end of the first connecting rod 51 is rotatably connected to the middle part of the second connecting rod 52;

[0066] The central axis of the upper sliding pipe column 221 extends outward from both sides to the outer end. A set of upper sliding grooves 53 with a horizontal main body are arranged on the vehicle frame 10. The central axis is restricted to be at the upper sliding grooves 53, and a nut structure is arranged at the outer end of the central axis, which can ensure that the upper sliding pipe column 221 can only perform translational operations at the upper sliding grooves 53 without torsion.

[0067] A second servo cylinder 54 is rotatably arranged at the outer end of the second connecting rod 52, and the rear end of the second servo cylinder 54 is rotatably connected to the vehicle frame 10. Among them, the first connecting rod 51, the second connecting rod 52 (the part of the first connecting rod 51 and the vehicle frame), and the vehicle frame (the part of the rotating point of the upper sliding pipe column and the second connecting rod 52) construct a triangular structure. Therefore, through such a structure, it can be ensured that the upper sliding pipe column 221 can only perform translational operations under the restriction of the upper sliding grooves 53. Therefore, under the operation of the second servo cylinder 54, by controlling the position of the outer end of the second connecting rod 52, and then controlling the position of the upper sliding pipe column 221 at the upper sliding grooves 53 through the first connecting rod 51, finally changing the position of the upper swing arm 22 to adjust the inclination angle of the wheel 26.

[0068] Therefore, this structure can ensure the connection and support function of the entire upper swing arm 22. At the same time, through this triangular structure, the stability of the entire structure can be improved, and the inward or outward load at the upper swing arm 22 can be mainly borne by the connection between the rear end of the second link 52 and the vehicle frame 10. And through the principle similar to the lever of the second link 52, the bearing capacity distributed to the second servo cylinder 54 is greatly reduced. Therefore, the load of the second servo cylinder 54 can be reduced, and its bearing structure is stable during the inclination angle adjustment process, and the operation is more accurate and controllable.

[0069] Appropriately control the inclination angle of the wheel 26, especially applied to small tires with a small contact surface and an arc contact surface. When the inclination angle of the wheel 26 is appropriately increased, the contact point between the vehicle and the ground can be moved outward, increasing the triangular area of the overall three-wheel grounding of the vehicle and also increasing the length of the corresponding stress arm. Therefore, the lateral support force can be increased. At the same time, for the vehicle wheels (specifically the rubber tire part), the acting force can be made more linear, reducing the phenomenon of the wheel being distorted due to the lateral acting force, and the center of gravity of the vehicle can be appropriately lowered. Therefore, the lateral support force and stability of the vehicle can be improved. Refer to Figure 10 , where the green line structure is the state diagram of the wheel after the inclination angle control. It can be seen from the figure that the structure of the wheel is adjusted from the original blue solid line to the blue dotted line, its height is appropriately reduced, the ground contact surface of the wheel moves outward, and the wheel (especially the part of the rubber tire in contact with the ground) greatly increases the lateral support force and reduces the situation of its distortion and deformation.

[0070] In order to obtain the actual vehicle attitude of the vehicle, especially the height and angular travel of the left and right wheels, rotation angle sensors are arranged at the lower sliding pipe columns 211 inside the left and right lower swing arms 21. The angle sensor can be a Hall sensor structure. A vertical angle sensor can be arranged at the vehicle frame 10, and this sensor is used to obtain the deflection angle of the vehicle frame 10 corresponding to the vertical angle.

[0071] This solution also includes a vehicle anti-tipping control method, which is applied to the above adjustable swing arm type suspension structure and includes:

[0072] Refer to Figure 11 , through the clamping position adjustment mechanism 4, control the positions of the upper clamping plate 41 and the lower clamping plate at the leaf spring 25, and set multiple stroke positions at the distance from the center of the vehicle frame 10. These stroke position points correspond to A1, A2, A3, A4, and A5 from the inside to the outside;

[0073] The position of the central axis at the upper sliding groove 53 is controlled by the inclination adjusting mechanism 5, and multiple stroke positions are set at distances from the center of the vehicle frame 10. These stroke position points correspond to B1, B2, B3, and B4 from the inside to the outside; these position corresponding points can be evenly arranged, unevenly arranged, or can be a virtual arrangement point, that is, each time it is set, it can be appropriately arranged according to its sequence, and each point position can be different each time it is set, so it can prevent wear and other situations from occurring at fixed point positions during long-term use, thereby improving its service life;

[0074] In the initial state, the position adjusting mechanism controls the stroke position to point A1, and the inclination adjusting mechanism controls the stroke position to point B4;

[0075] The rotation angle value of the corresponding lower swing arm 21 is obtained through the rotation angle sensor, and the load value of the vehicle is calculated by the method of corresponding table values; when calculating the load value, the table values can be arranged linearly from the empty vehicle load state to the designed full load state;

[0076] If the load value of the vehicle is greater than the set value, the position adjusting mechanism 4 is controlled to make the strokes on both sides be at A2 or the outside of A2; therefore, by controlling the leaf spring 25 through the position adjusting mechanism 4, the positions of the two support points are changed outwards, so the elasticity of the leaf spring 25 can be increased, thereby increasing the supporting force of the leaf spring on the wheel, reducing the amplitude of the up and down stroke of the wheel, and improving the anti-tipping efficiency of the wheel;

[0077] Through the vehicle electronic control unit, the real-time speed value and the real-time steering angle value of the current vehicle are obtained; the real-time speed value is converted into a real-time speed reference value by the method of corresponding table values, and the steering angle value is converted into a steering angle reference value by the method of corresponding table values. If the product value of the real-time speed reference value and the steering angle reference value is greater than the set value, the position adjusting mechanism corresponding to the outer turning wheel controls the stroke to be at A3 or the outside of A3, and the inclination adjusting mechanism controls the stroke to be at B3 or the inside of B3; when the vehicle is turning, it can be regarded as an operation to overcome the centrifugal force. Its turning radius matches the steering angle controlled by the vehicle at that time, but according to the inertia formula, it matches the speed and mass. Therefore, in the simplified operation, differential control based on the steering angle and the real-time speed can improve the turning stability of the vehicle and reduce the occurrence of rollover; actually, this solution calculates the corresponding formula through the speed variable, the steering angle variable, and the vehicle mass (including load), and implements the corresponding leaf spring 35 control and inclination control to achieve differential vehicle anti-tipping control;

[0078] After the above control, the rotation angle sensors of the left and right lower sliding pipe columns 211 are used to obtain the corresponding rotation angle values, and combined with the feedback value of the vertical angle sensor at the vehicle frame 10, the real-time roll angle value of the current vehicle is obtained; if the real-time roll angle value is greater than the set value, the position adjustment mechanism on the outer side of the roll is controlled to a position at or outside A4, and the inclination adjustment mechanism is controlled to a position at or inside B2.

[0079] In some embodiments, in the initial state, by providing options including comfort or sport for the driver, if the driver selects the comfort option, the original stroke position point is retained; if the driver selects the sport option, the position adjustment mechanism is controlled to a position at or outside A2, and the inclination adjustment mechanism is controlled to a position at or inside B3. Therefore, different driving modes can be provided for the driver, and the vehicle can be actively adjusted by the driver to better conform to the current road conditions or driving requirements, and reduce the occurrence of roll.

[0080] In summary, the present solution is an adjustable swing arm type suspension structure. The main body forms a swing structure in the shape of a quadrilateral through the upper swing arm, lower swing arm, steering seat and vehicle frame structure. Specifically, in the initial state, a trapezoidal structure is constructed. This structure is for the suspension of the three-wheeler structure of the front two wheels, which can increase the contact area between the wheels and the ground when the wheels are walking and turning, and control a certain camber angle of the wheels under high load conditions, thereby improving the driving stability of the vehicle and reducing the occurrence of roll phenomenon;

[0081] The upper swing arm and the lower swing arm are both connected to the steering seat through a horizontally arranged ball head structure, which has the characteristics of convenient installation and maintenance and flexible and reliable use. For the lower swing arm, the ground clearance can be increased to reduce the occurrence of bottoming.

[0082] The shock absorption structure of the present solution is mainly implemented by a leaf spring. By arranging a leaf spring between the upper swing arm and the lower swing arm, the structural complexity of the suspension can be greatly reduced, the structure can be made more concise and efficient, the occupation of the vehicle body space by the complex suspension structure can be reduced, the space utilization rate of the vehicle can be improved, and the unsprung mass of the suspension can be reduced, making the suspension simple and efficient, and improving the driving flexibility and controllability of the vehicle;

[0083] The leaf spring implements the connection operation to the middle part of the vehicle frame through a position adjustment mechanism, and realizes the independent adjustment of the single-sided connection point through the position adjustment mechanism. Therefore, according to the characteristics of the leaf spring itself, the stroke and elastic support force of the leaf spring are controlled through the position adjustment mechanism. Therefore, the roll of the load-bearing wheels can be controlled to reduce the situation, thereby improving the controllability of the vehicle, and in extreme cases, the support force can be increased to reduce the roll situation;

[0084] The leaf spring implements the control of the leaf spring stroke and elastic support force through a clamping position adjustment mechanism, which can adjust the vehicle operation mode, and the suspension hardness and total stroke height, so as to improve driving pleasure and controllability;

[0085] By arranging an inclination angle adjustment mechanism at the upper swing arm sliding pipe column, the wheel inclination angle can be adjusted under extreme conditions. Specifically, it is to moderately adjust the "toe-out" roll of the high-load wheels, so as to increase the width of the ground contact point at the lower end of the wheel, improve the lateral support force, and make the force on the wheel more directional, improve the stability of the vehicle under extreme conditions, and reduce the occurrence of roll;

[0086] A vehicle anti-tipping control method in this solution mainly uses a clamping position adjustment mechanism and an inclination angle adjustment mechanism to control the leaf spring and the upper swing arm, and realizes the control of the support force of the leaf spring and the corresponding vehicle tilt angle, so as to improve the stability and controllability of the vehicle under extreme conditions. Specifically, under the control and coordination of the vehicle electronic control unit ECU, by obtaining the vehicle load value, speed value, turning angle value and roll angle value, targeted adjustment control is carried out, and the differential stroke control under driving conditions is specifically implemented, and the adjustment operation of preventing roll and improving vehicle controllability can be realized.

Claims

1. Adjustable swing arm suspension structure, characterized by: It comprises a lower swing arm and an upper swing arm, wherein the lower swing arm is a triangular structure, and the upper swing arm is a connecting rod structure. The inner sides of the upper swing arm and the lower swing arm are connected to the vehicle frame through a horizontally arranged sliding column structure, and the outer ends of the upper swing arm and the lower swing arm are connected to the steering seat through a horizontally arranged ball head structure, so as to form a quadrilateral swing structure when viewed from the front. The sliding column on the inner side of the upper swing arm is provided with an inclination adjustment mechanism, and the inclination adjustment mechanism includes a servo cylinder connected to the middle axis of the sliding column of the upper swing arm, the two ends of the middle axis extend outward, and a slide groove matching the middle axis is arranged on the frame, and the servo cylinder is used to control the position of the middle axis and the upper swing arm at the slide groove; When the quadrilateral swing structure is in the initial state, the connecting line of the rotation points at both ends of the upper swing arm, the connecting line of the corresponding rotation points of the upper swing arm and the lower swing arm sliding column at the frame, the connecting line of the rotation points at both ends of the lower swing arm and the connecting line of the rotation points of the upper swing arm and the lower swing arm corresponding to the steering seat construct a trapezoidal structure.

2. The adjustable swing arm suspension structure according to claim 1, characterized in that: A first connecting rod is rotatably connected to the central axis of the sliding column on the inner side of the upper swing arm, and a second connecting rod is rotatably connected to the frame. The rear end of the first connecting rod is rotatably connected to the middle part of the second connecting rod, and the two ends of the servo cylinder are respectively rotatably connected to the frame and the outer end of the second connecting rod.

3. The adjustable swing arm suspension structure according to claim 1, characterized in that: A steering rod is arranged on one side of the steering seat, the outer end of the steering rod is connected to the steering seat through a horizontally arranged ball head structure, the inner end of the steering rod is connected to the middle cross rod through the ball head structure, the middle cross rod is connected to the steering gear of the vehicle, the middle cross rod is a horizontal U-shaped structure, the middle part is connected to the inner side of the steering rod through the ball head structure, and the outer ends of both sides are arranged with vertically arranged ball head structures, and the top of the ball head structure is arranged with a follower arm, the follower arm on one side is connected to the frame through the ball head structure, and the follower arm on the other side is connected to the steering gear, and the steering rod has an adjustable length structure.

4. The adjustable swing arm suspension structure according to claim 1, characterized in that: A rotation angle sensor is arranged at the sliding column structure on the inner side of the lower swing arm.

5. The adjustable swing arm suspension structure according to claim 1, characterized in that: A leaf spring is arranged between the lower swing arm and the upper swing arm, the middle part of the leaf spring is connected to the vehicle frame, and the outer end of the leaf spring is connected to the inner side of the steering seat through an upright ball head structure.

6. The adjustable swing arm suspension structure according to claim 5, characterized in that: The center points of the ball heads of the upper swing arm, the leaf spring and the lower swing arm on the steering seat are in a straight line alignment state, and the downward extension line of the straight line passes through the contact surface between the wheel and the ground.

7. The adjustable swing arm suspension structure according to claim 5, characterized in that: A positioning adjustment mechanism is arranged at the connection between the middle part of the leaf spring and the frame. The positioning adjustment mechanism includes an upper clamping plate and a lower clamping plate. The upper clamping plate and the lower clamping plate clamp the leaf spring in a clamping arrangement state. Slide blocks are provided on both sides of the upper clamping plate and the lower clamping plate. A sliding groove cooperating with the slide block is arranged on the frame. A structural block is arranged at the outer end of the slide block. A first servo cylinder is arranged on the side of the structural block. The first servo cylinder is used to control the position of the structural block, the slider, the upper clamping plate, the lower clamping plate and the leaf spring.

8. A method for controlling a vehicle's anti-dumping, applied to the adjustable swing arm suspension structure according to any one of claims 1 to 7, characterized in that: include: The positions of the upper clamping plate and the lower clamping plate at the leaf spring are controlled by a position adjustment mechanism, and a plurality of travel positions are set at a distance from the center of the frame, and the travel position points correspond to A1, A2, A3, A4 and A5; The position of the middle axis at the upper slide groove is controlled by the inclination adjustment mechanism, and a plurality of travel positions are set at a distance from the center of the frame, and the travel position points correspond to B1, B2, B3 and B4; In the initial state, the position control stroke of the positioning adjustment mechanism is point A1, and the position control stroke of the inclination adjustment mechanism is point B4; Obtain the current real-time speed value and real-time steering angle value of the vehicle through the vehicle electronic control unit; The real-time speed value is converted into a real-time speed reference value by a table value corresponding method, and the rotation angle value is converted into a rotation angle reference value by a table value corresponding method. If the product value of the real-time speed reference value and the rotation angle reference value is greater than the set value, the control stroke of the positioning adjustment mechanism is A2 or the outer side of A2, and the control stroke of the tilt adjustment mechanism is B3 or the inner side of B3; After the above control, the corresponding rotation angle value is obtained by the rotation angle sensor of the lower sliding column on the left and right sides, and the real-time roll angle value of the current vehicle is obtained in combination with the feedback value of the vertical angle sensor at the frame; if the real-time roll angle value is greater than the set value, the control stroke of the positioning adjustment mechanism on the outside of the turn is A3 or the outside of A3, and the control stroke of the tilt adjustment mechanism on the outside of the roll is B2 or the inside of B2.

9. The vehicle anti-dumping control method according to claim 8, characterized in that: In the initial state, by providing the driver with options including comfort or sport, if the driver selects the comfort option, the original travel position point is retained; if the driver selects the sport option, the positioning adjustment mechanism is controlled to have a travel of A2 or the outside of A2, and the tilt adjustment mechanism is controlled to have a travel of B3 or the inside of B3.

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