Variable stiffness air spring and control method

Abstract

The application discloses a variable stiffness air spring and a control method thereof. The variable stiffness air spring comprises a gas bag and a piston connected with the gas bag. The top end of the gas bag is connected with a fixed plate. A partition plate is arranged in the gas bag to divide the gas bag into a main cavity located at the lower part and a secondary cavity located at the upper part. A plurality of groups of division units are arranged in the secondary cavity in a radial manner. A sub-cavity is formed between two adjacent division units. Each division unit comprises a plurality of cylinder bodies connected in sequence. The cylinder body located at the outer side is connected with the inner wall of the gas bag in a fit manner. The two ends of the cylinder body are fixed to the partition plate and the fixed plate. A buffer cavity is formed in the cylinder body. A first valve body and a second valve body are arranged on the partition plate and are respectively connected with the sub-cavity and the buffer cavity. The variable stiffness air spring can perform more subdivided adjustment on the vehicle damping system, and the driving comfort is improved. The control method can perform early adjustment on the vehicle damping system by predicting the road conditions to be passed by the tire.

Description

Technical Field

[0001] This invention relates to air springs, and more specifically, to a variable stiffness air spring and its control method. Background Technology

[0002] As people's demands for vehicle driving performance continue to increase, air suspension has been applied in the automotive field. Air suspension adjusts the stiffness of the suspension by inflating and deflating air springs. On smooth roads, the air springs are inflated for a better driving feel, while on bumpy roads, they are deflated for better filtering of bumps. Another method involves separating the main airbag with a secondary airbag, adjusting the total gas volume by connecting the main and secondary airbags to adjust the suspension stiffness. However, neither method allows for pre-adjustment of the air springs based on road conditions; adjustments must be made manually. If adjustments aren't made in time when encountering bumpy roads, comfort will decrease, and the adjustment precision of existing air springs is poor. Summary of the Invention

[0003] The purpose of this invention is to provide a variable stiffness air spring and a control method thereon. The variable stiffness air spring can make more detailed adjustments to the vehicle's shock absorption system, thereby improving driving comfort. The control method can adjust the vehicle's shock absorption system in advance by predicting the road conditions that the tires will encounter, thus avoiding a decrease in driving comfort when suddenly entering bumpy road conditions.

[0004] To achieve the above objectives, the present invention provides a variable stiffness air spring, which includes an air bladder and a piston connected to the air bladder. A fixed plate is connected to the top of the air bladder, and a partition plate is provided inside the air bladder to divide the air bladder into a main bladder cavity located at the bottom and a secondary bladder cavity located at the top. Multiple sets of dividing units are radially arranged in the secondary bladder cavity, and a sub-bladder cavity is formed between two adjacent dividing units. Each dividing unit includes multiple cylinders connected in sequence. The outermost cylinder is fitted and connected to the inner wall of the air bladder. Both ends of the cylinder are fixed to the partition plate and the fixed plate. A buffer cavity is formed inside the cylinder. A first valve body and a second valve body are provided on the partition plate, respectively connecting the sub-bladder cavity and the buffer cavity.

[0005] Preferably, the second valve body includes a solenoid valve body, the valve core of the solenoid valve body is disposed through a second through hole in the partition plate, and a sealing plate is fixedly connected to the bottom end of the valve core.

[0006] Preferably, a light rod is coaxially fixed to the upper end of the solenoid valve body, and the upper end of the light rod extends to the fixing plate and is connected to a mounting plate. The mounting plate is detachably installed on the outside of the fixing plate.

[0007] Preferably, the center of the optical rod is provided with a central hole for the wire harness to pass through, one end of the wire harness is connected to the solenoid valve body, and the other end is connected to an external processor.

[0008] Preferably, a movable stopper plate is provided inside the cylinder and slidably sleeved on the optical rod. A compression reserve chamber is formed inside the cylinder above the movable stopper plate, and a spring is provided inside the compression reserve chamber.

[0009] Preferably, the dividing plate is provided with a first through hole communicating with the cyst cavity, and the first valve body is an electric butterfly valve provided at the first through hole.

[0010] Preferably, the piston has an air inlet groove at its center that communicates with the main chamber, and an air inlet hole is provided on the side of the air inlet groove.

[0011] Preferably, the upper inner wall of the airbag is integrally cast with a metal inner wall, the partition plate is screwed to the metal inner wall, and the lower end of the fixing plate is provided with an fitting groove for fitting the upper end of the airbag.

[0012] Another aspect of the present invention provides a variable stiffness air spring control method. This variable stiffness air spring control method employs a control system, which includes a lidar installed on the front of the vehicle for collecting road condition information, a vehicle speed sensor installed inside the vehicle, and a direction angle sensor for collecting steering wheel angle. A processor is connected to the lidar, vehicle speed sensor, and direction angle sensor. The processor is connected to the variable stiffness air springs as described, which are respectively installed at the left front wheel, right front wheel, left rear wheel, and right rear wheel axle of the vehicle. The variable stiffness air spring control method predicts the road conditions that the left front wheel, right front wheel, left rear wheel, and right rear wheel will pass through based on the collected road condition information, vehicle speed information, and direction angle information, and adjusts the opening and closing of the first valve body and / or the second valve body in advance.

[0013] Preferably, the opening and closing of the other first or second valve bodies, except for the second valve body located at the center, are performed in pairs, and the buffer chamber is configured to be elastically buffered and expanded by the increase of pressure.

[0014] According to the above technical solution, the variable stiffness air spring in this invention can make more detailed adjustments to the vehicle's shock absorption system, thereby improving driving comfort. This control method can adjust the vehicle's shock absorption system in advance by predicting the road conditions that the tires will pass through, thus avoiding a decrease in driving comfort when suddenly entering bumpy road conditions.

[0015] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of the distribution structure of the cylinder on the dividing plate in this invention; Figure 3 This is a schematic diagram of the overall structure of another preferred embodiment of the present invention; Figure 4 This is the control flowchart of the present invention.

[0017] Explanation of reference numerals in the attached figures 1-Piston; 2-Inlet groove; 3-Inlet hole; 4-Airbag; 5-Divider plate; 6-Solenoid valve body; 7-Shine rod; 8-Spring; 9-Mounting plate; 10-Wire harness; 11-Main chamber; 12-Buffer chamber; 13-Modible plug plate; 14-Compression spare chamber; 15-Second through hole; 16-First through hole; 17-Cylinder; 18-Second chamber; 19-Sealing plate; 20-Valve core; 21-Matching groove; 22-Metal inner wall; 23-Fixing plate. Detailed Implementation

[0018] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0019] In this invention, unless otherwise stated, directional terms such as "up, down, left, right, front, back, inside, outside" in the terminology only represent the orientation of the term in its normal use or are common terms understood by those skilled in the art, and should not be regarded as a limitation on the term.

[0020] See Figure 1-3 The variable stiffness air spring shown includes an airbag 4 and a piston 1 connected to the airbag 4. A fixing plate 23 is connected to the top of the airbag 4. A partition plate 5 is provided inside the airbag 4 to divide the airbag 4 into a main chamber 11 located at the bottom and a secondary chamber located at the top. Multiple sets of dividing units are arranged radially inside the secondary chamber. A sub-chamber 18 is formed between two adjacent dividing units. The dividing unit includes multiple cylinders 17 connected in sequence. The outer cylinder 17 is fitted and connected to the inner wall of the airbag 4. The two ends of the cylinder 17 are fixed to the partition plate 5 and the fixing plate 23. A buffer chamber 12 is formed inside the cylinder 17. A first valve body and a second valve body are provided on the partition plate 5, which respectively connect the sub-chamber 18 and the buffer chamber 12.

[0021] By implementing the above technical solution, the variable stiffness air spring can make more detailed adjustments to the vehicle's shock absorption system, improving driving comfort. This control method can adjust the vehicle's shock absorption system in advance by predicting the road conditions the tires will encounter, avoiding a decrease in driving comfort when suddenly entering bumpy road conditions.

[0022] In one implementation, see Figure 2 As shown, there are 6 groups of dividing units arranged at equal intervals along the circumference. Each group of dividing units contains 4 cylinders 17. The innermost cylinder 17 is shared by all 6 groups of dividing units. Multiple cylinders 17 are used as buffer chambers 12. When it is predicted that the road condition that the wheel is about to run over is a bumpy road condition, the second valve body is opened in advance to connect the buffer chamber 12 with the main chamber 11, thereby increasing the volume of compressible gas and improving the comfort of the vehicle.

[0023] The number of second valves that open depends on the degree of road bumps. However, except for the second valve located in the middle, the other second valves should be opened in pairs, such as two, four, or six second valves on the diagonal, to make the pressure more even.

[0024] In this embodiment, the cylinder 17 not only serves to provide the buffer chamber 12, but also acts as a divider to form multiple sub-cavities 18. The first valve on each sub-cavity 18 can be opened or closed manually to adjust the elasticity of the air spring as a normal adjustment, without automatically adjusting with changes in road conditions.

[0025] In other words, this invention combines the normal adjustment of the plenum 18 with the dynamic adjustment of the buffer chamber 12 to improve the driving experience. The adjustment range is further refined, giving drivers more room for adjustment according to their own needs.

[0026] In this embodiment, to further provide a second valve body, the second valve body includes a solenoid valve body 6, the valve core 20 of the solenoid valve body 6 is disposed through the second through hole 15 on the partition plate 5, and a sealing plate 19 is fixedly connected to the bottom end of the valve core 20. By electromagnetically controlling the extension and retraction of the valve core 20 through the solenoid valve body 6, the sealing plate 19 can be driven to open or close the second through hole 15.

[0027] In this embodiment, to further provide an installation method for the solenoid valve body 6, a guide rod 7 is coaxially fixed to the upper end of the solenoid valve body 6. The upper end of the guide rod 7 extends to the fixing plate 23 and is connected to a mounting plate 9. The mounting plate 9 is detachably installed on the outside of the fixing plate 23. The mounting plate 9 and the fixing plate 23 can be fixed by bolt installation or by laser welding.

[0028] In this embodiment, the optical rod 7 has a central hole for the wire harness 10 to pass through. One end of the wire harness 10 is connected to the solenoid valve body 6, and the other end is connected to an external processor. This arrangement provides a way to arrange the wire harness 10 for connecting the solenoid valve body 6.

[0029] In this embodiment, a movable stopper plate 13 is slidably sleeved on the guide rod 7 inside the cylindrical body 17. A compression reserve chamber 14 is formed above the movable stopper plate 13 inside the cylindrical body 17, and a spring 8 is installed inside the compression reserve chamber 14. The two ends of the spring 8 are respectively connected to the movable stopper plate 13 and the fixed plate 23. When the second valve body is opened, the pressure in the buffer chamber 12 increases instantaneously, and the compression reserve chamber 14 is compressed under the push of the movable stopper plate 13 for further buffering. In addition, it also increases the gas capacity of the airbag 4, thereby further increasing comfort. Furthermore, the movable stopper plate 13 can be quickly reset by the reset action of the spring 8.

[0030] In this embodiment, to further provide a way to open or close the first through hole 16, the dividing plate is provided with a first through hole 16 communicating with the sub-cavity 18, and the first valve body is an electric butterfly valve provided at the first through hole 16.

[0031] In this embodiment, to further provide an air intake method, the piston 1 is provided with an air intake groove 2 that communicates with the main cavity 11 at its center, and an air intake hole 3 is provided on the side of the air intake groove 2.

[0032] In this embodiment, the upper inner wall of the airbag 4 is integrally cast with a metal inner wall 22, the partition plate 5 is screwed to the metal inner wall 22, and the lower end of the fixing plate 23 is provided with an fitting groove 21 that fits into the upper end of the airbag 4.

[0033] This design allows for the detachable connection between the partition plate 5, the cylinder 17, and the fixing plate 23 and the metal inner wall 22, facilitating the replacement of internal parts in case of damage.

[0034] See Figure 4As shown, another aspect of the present invention provides a variable stiffness air spring control method. This method employs a control system comprising a lidar mounted on the front of the vehicle for collecting road condition information, a vehicle speed sensor installed inside the vehicle, and a steering angle sensor for collecting steering wheel angle information. A processor is connected to the lidar, vehicle speed sensor, and steering angle sensor. The processor is connected to variable stiffness air springs, as described, respectively located at the left front wheel, right front wheel, left rear wheel, and right rear wheel axle. The variable stiffness air spring control method predicts the road conditions that the left front wheel, right front wheel, left rear wheel, and right rear wheel will encounter based on the collected road condition information, vehicle speed information, and steering angle information, and adjusts the opening and closing of the first valve body and / or the second valve body in advance. In this way, the vehicle can adjust the stiffness of the variable stiffness air springs at the corresponding wheel positions in advance when entering bumpy road conditions, and adjust the number of second valve bodies that need to be opened according to the road condition information. For example, when the tires are moving in a straight line, the road condition information scan detects a 4cm high speed bump 20m ahead of the left and right front wheels. At this time, combined with the vehicle speed data, the estimated time to reach the speed bump is predicted. When the time is reached, the corresponding number of second valves are opened instantly. This increases the comfort when passing the speed bump. After passing the speed bump, the second valves are closed, and the vehicle returns to normal.

[0035] In this embodiment, to further enhance the form experience, the opening and closing of the other first or second valve bodies, except for the second valve body located in the center, are performed in pairs, and the buffer chamber 12 is configured to be elastically buffered and expanded by the increase of pressure.

[0036] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0037] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0038] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A variable stiffness air spring, characterized in that, The device includes an airbag (4) and a piston (1) connected to the airbag (4). A fixing plate (23) is connected to the top of the airbag (4). A partition plate (5) is provided inside the airbag (4) to divide the airbag (4) into a main chamber (11) located at the bottom and a secondary chamber located at the top. Multiple sets of dividing units are arranged radially inside the secondary chamber. A sub-chamber (18) is formed between two adjacent dividing units. The dividing unit includes multiple cylinders (17) connected in sequence. The outer cylinder (17) is attached to the inner wall of the airbag (4). The two ends of the cylinder (17) are fixed to the partition plate (5) and the fixing plate (23). A buffer chamber (12) is formed inside the cylinder (17). A first valve body communicating with the sub-chamber (18) and a second valve body communicating with the buffer chamber (12) are provided on the partition plate (5). The second valve body includes a solenoid valve body (6), the valve core (20) of the solenoid valve body (6) is disposed through the second through hole (15) on the partition plate (5), and a sealing plate (19) is fixedly connected to the bottom end of the valve core (20). The upper end of the solenoid valve body (6) is coaxially fixed with a light rod (7), the upper end of the light rod (7) extends to the fixing plate (23) and is connected to a mounting plate (9), and the mounting plate (9) is detachably installed on the outside of the fixing plate (23). The cylinder (17) is provided with a movable stopper plate (13) that is slidably sleeved on the light rod (7). A compression spare cavity (14) is formed above the movable stopper plate (13) in the cylinder (17). A spring (8) is provided in the compression spare cavity (14).

2. The variable stiffness air spring according to claim 1, characterized in that, The light rod (7) has a central hole for the wire harness (10) to pass through. One end of the wire harness (10) is connected to the solenoid valve body (6), and the other end is connected to an external processor.

3. The variable stiffness air spring according to claim 1, characterized in that, The partition plate (5) is provided with a first through hole (16) connecting the sub-cavity (18) and the main cavity (11), and the first valve body is an electric butterfly valve provided at the first through hole (16).

4. The variable stiffness air spring according to claim 1, characterized in that, The piston (1) has an air inlet groove (2) at its center that communicates with the main chamber (11), and an air inlet hole (3) is provided on the side of the air inlet groove (2).

5. The variable stiffness air spring according to claim 1, characterized in that, The upper inner wall of the airbag (4) is integrally cast with a metal inner wall (22), the partition plate (5) is screwed to the metal inner wall (22), and the lower end of the fixing plate (23) is provided with a fitting groove (21) that fits into the upper end of the airbag (4).

6. A method for controlling a variable stiffness air spring, characterized in that, The variable stiffness air spring control method employs a control system comprising a lidar mounted on the front of the vehicle for collecting road condition information, a vehicle speed sensor installed inside the vehicle, and a direction angle sensor for collecting steering wheel angle. A processor is connected to the lidar, vehicle speed sensor, and direction angle sensor. The processor is connected to variable stiffness air springs as described in any one of claims 1-5, respectively located at the left front wheel, right front wheel, left rear wheel, and right rear wheel axle. The variable stiffness air spring control method predicts the road conditions that the left front wheel, right front wheel, left rear wheel, and right rear wheel will pass through based on the collected road condition information, vehicle speed information, and direction angle information, and adjusts the opening and closing of the first valve body and / or the second valve body in advance.

7. The variable stiffness air spring control method according to claim 6, characterized in that, Except for the second valve body located at the center, the opening and closing of the other first valve bodies or second valve bodies are performed in pairs, and the buffer chamber (12) is configured to be elastically buffered and expanded by the increase of pressure.

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