Active suspension structure and active suspension system

Abstract

The invention discloses an active suspension structure which comprises a linear actuator, a spring assembly, a damper and a mounting frame. The linear actuator is a ball screw assembly which is of a hollow structure and is driven by a motor to do linear motion. The upper end of the spring assembly is connected with the ball screw pair assembly, the lower end of the spring assembly is connected with the mounting frame, and the spring assembly is stretched or compressed along with the movement of the ball screw pair assembly; the damper is arranged in a hollow structure in the linear actuator, and a damper piston is arranged at the front end of the damper; the upper end of the mounting frame is connected with the damper piston, the middle of the mounting frame is connected with the spring assembly, and a mounting hole for connecting a hub is formed in the bottom of the mounting frame; the bottom mounting frame moves up and down along with stretching and compression of the spring assembly. All the components are integrated into one module, all the components are modularized, the height, rigidity and damping characteristics of the suspension can be adjusted in real time, the response speed is high, and the comfort level and durability are improved.

Description

Technical Field

[0001] The invention relates to an automobile shock absorbing device, in particular to an active suspension system and an active suspension system. Background Art

[0002] The automobile suspension structure is an important component connecting the wheels and the body. Its performance directly affects the vehicle's power, economy, braking and handling stability. Among these performance indicators, the body height, that is, the height of the vehicle's center of mass, plays a vital role. The ideal body height is different under different driving conditions. For example, lowering the body when driving at high speed can reduce air resistance and improve economy; and appropriately increasing the body height when driving on uneven roads can avoid chassis scratches and improve passability.

[0003] The structure of the linear active suspension is mainly composed of an actuator, a spring and a shock absorber. The spring is used to control the height of the vehicle and the stiffness of the suspension system to ensure good driving smoothness. The shock absorber is used to adjust the damping force of the suspension, and the actuator adjusts the stiffness and damping characteristics of the suspension according to the instructions of the controller. Its disadvantages are: 1. The actuator, spring and shock absorber are usually independently set components, which makes the manufacture and maintenance of the suspension more complicated, and maintenance and replacement are not easy, which reduces the reliability of the system. 2. The actuator has low displacement accuracy and poor response speed. Under driving conditions that require fast response, the suspension cannot be adjusted and responded in time, affecting the comfort of the passengers. 3. It is easy to wear between components, resulting in reduced durability of the suspension and affecting the comfort of passengers. Summary of the invention

[0004] In view of the above-mentioned existing technical problems, the present invention provides an active suspension structure in which various components are integrated into modularization, and the height, stiffness and damping characteristics of the suspension can be adjusted in real time, with fast response speed, good comfort and durability.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: an active suspension structure, including a linear actuator, a spring assembly, a damper and a mounting frame; the linear actuator is a ball screw subassembly, the ball screw subassembly is a hollow structure, and is driven by a motor to perform linear motion; the upper end of the spring assembly is connected to the ball screw subassembly, and the lower end of the spring assembly is connected to the mounting frame, and the spring assembly is stretched or compressed as the ball screw subassembly moves; the damper is arranged in the hollow structure inside the linear actuator, and a damper piston is provided at the front end of the damper; the upper end of the mounting frame is connected to the damper piston, the middle of the mounting frame is connected to the spring assembly, and the bottom of the mounting frame is provided with a mounting hole for connecting the wheel hub; the bottom mounting frame moves up and down as the spring assembly is stretched and compressed; the mounting frame is squeezed by the vehicle body to push the damper piston upward and compress the spring assembly.

[0006] The present invention further provides that the ball screw sub-assembly is a reverse ball screw sub-assembly, comprising a steel ball, a ball nut, a screw which also serves as an output shaft, a rotor and a stator; an open spiral nut raceway is provided on the inner surface of the ball nut, the ball nut is sleeved on the screw, and a circulating load-bearing raceway is provided on the outer surface of the rear end of the screw; the steel balls are evenly arranged between the nut raceway and the circulating load-bearing raceway along the circumferential direction to form a ball thread transmission mechanism; the ball nut is connected to the stator through an upper bearing assembly and a lower bearing assembly, the rotor is arranged between the stator and the ball nut, the ball nut is driven to rotate by a motor, driving the screw to make a linear motion, and an upper shell for setting the motor is provided at the upper end of the ball nut.

[0007] Furthermore, the stator is provided with a rigid shell outside, and an upper isolator and a lower isolator are respectively provided at upper and lower ends between the stator and the shell.

[0008] According to a further feature of the present invention, a plurality of ball spline grooves are evenly distributed on the circumference of the lead screw, and a ball spline is connected between the lead screw and the rigid housing.

[0009] According to a further feature of the present invention, an upper vernier magnetic ring is disposed at the upper end of the damper, and a lower vernier magnetic ring is disposed between the damper piston and the mounting frame.

[0010] The present invention further comprises a top connecting shell disposed on the upper portion of the linear actuator, a position sensor disposed inside the linear actuator, the upper end of the position sensor being mounted inside the top connecting shell, the lower end being connected to a position sensor rod, the position sensor rod extending downward into the mounting frame; a load sensor is disposed on the top connecting shell.

[0011] According to a further aspect of the present invention, an encoder is disposed in the upper shell.

[0012] Furthermore, the spring assembly is an air spring, the upper end of the air spring is connected to the lead screw via an upper spring mounting seat, and the lower end of the air spring is connected to the mounting frame via a lower spring mounting seat.

[0013] According to the present invention, the spring assembly is a coil spring, the upper end of the coil spring is connected to the lead screw via an upper spring mounting seat, and the lower end of the coil spring is connected to the mounting frame via a lower spring mounting seat.

[0014] In addition, the present invention also provides an active suspension system, including any one of the above-mentioned active suspension structures, and a controller; the active suspension structure has four groups, which are respectively arranged under the vehicle body at the left front wheel, the vehicle body at the right front wheel, the vehicle body at the left rear wheel, and the vehicle body at the right rear wheel, and are connected to the corresponding wheel hubs through a mounting frame; the sensor on each group of active suspension structures is connected to the controller. Since the active suspension system includes any one of the above-mentioned active suspension structures, it has the same technical effect as the above-mentioned active suspension structure.

[0015] The beneficial effects of adopting the above technical solution are: the present invention integrates various components into a module, simplifies installation and maintenance, and improves the reliability of the system. In addition, the integrated design can better coordinate the work of various components. The compact design not only reduces the installation space required for the vehicle suspension system, but also reduces the unsprung mass, thereby improving the dynamic response and handling of the vehicle. The present invention adopts three independent load paths, and transmits different types of loads, namely static loads, dynamic adjustment loads and motion constraint loads, through spring assemblies, linear actuators and dampers respectively, which improves the dynamic response ability of the suspension system, can better adapt to complex road conditions, and provide higher comfort and handling. At the same time, by separating different load paths, the design of each path can be optimized to make it more focused on its specific function, thereby improving the overall performance of the system. By adjusting the input of the linear actuator, the system can quickly adjust the height, stiffness and damping characteristics of the suspension according to real-time road conditions and driving needs. Improve the adaptability of the system so that it can provide the best driving experience under various complex road conditions and maintain stability and safety. The combination of ball splines improves the torque transmission efficiency and rigidity of the system, while reducing wear and extending the life of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention;

[0017] Figure 2 It is a schematic diagram of the external structure of the present invention;

[0018] Figure 3 It is a structural schematic diagram of the linear actuator of the present invention;

[0019] Figure 4 This is a schematic diagram of the implementation of the present invention using a spiral spring;

[0020] Figure 5 It is a schematic diagram of the principle of the active suspension system of the present invention. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] An embodiment of the present invention: Figure 1 and Figure 2 As shown, an active suspension structure includes a linear actuator 7, a spring assembly, a damper 1 and a mounting frame 16; the linear actuator 7 is a ball screw subassembly, the ball screw subassembly is a hollow structure, and is driven by a motor to perform linear motion; the upper end of the spring assembly is connected to the ball screw subassembly, and the lower end of the spring assembly is connected to the mounting frame 16, and the spring assembly is stretched or compressed as the ball screw subassembly moves; the damper 1 is arranged in the hollow structure inside the linear actuator 7, and a damper piston 15 is provided at the front end of the damper 1; the upper end of the mounting frame 16 is connected to the damper piston 15, the middle of the mounting frame 16 is connected to the spring assembly, and the bottom of the mounting frame 16 is provided with a mounting hole for connecting to the wheel hub; the bottom mounting frame 16 moves up and down as the spring assembly is stretched and compressed; the mounting frame 16 is squeezed by the vehicle body to push the damper piston 15 upward and compress the spring assembly. When in use, the active suspension structure is set at the bottom of the vehicle undercarriage, and the mounting frame 16 is installed and connected to the wheel hub, wherein the spring assembly and the damper 1 are passive adjustment components, which are used to respond to the road and vehicle dynamic conditions when the vehicle is driving, and provide support and shock absorption. The linear actuator 7 can actively adjust the state of the spring assembly, and by controlling the linear actuator 7 to move up and down, compress or stretch the spring assembly, and at the same time drive the height of the mounting frame 16, the vehicle height and the rigidity of the spring assembly can be accurately controlled.

[0024] The present invention integrates various components such as the linear actuator 7, the spring assembly, the damper 1 and the mounting frame 16 into a module, which simplifies installation and maintenance and improves the reliability of the system. In addition, the integrated design can better coordinate the work of each component. The compact design not only reduces the installation space required for the vehicle suspension system, but also reduces the unsprung mass, thereby improving the dynamic response and handling of the vehicle. The present invention adopts three independent load paths, and transmits different types of loads, namely static loads, dynamic adjustment loads and motion constraint loads, through the spring assembly, the linear actuator 7 and the damper 1, respectively, which improves the dynamic response capability of the suspension system, can better adapt to complex road conditions, and provide higher comfort and handling. At the same time, by separating different load paths, the design of each path can be optimized, so that it can be more focused on its specific function, thereby improving the overall performance of the system. By adjusting the input of the linear actuator 7, the system can quickly adjust the height, stiffness and damping characteristics of the suspension according to real-time road conditions and driving needs. Improve the adaptability of the system so that it can provide the best driving experience under various complex road conditions and maintain stability and safety.

[0025] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 3As shown, the ball screw subassembly is a reverse ball screw subassembly, including a steel ball 24, a ball nut 2, a screw 33 which also serves as an output shaft, a rotor 5 and a stator 6; an open spiral nut raceway 26 is provided on the inner surface of the ball nut 2, the ball nut 2 is sleeved on the screw 33, and a circulating load-bearing raceway 25 is provided on the outer surface of the rear end of the screw 33; the steel balls 24 are evenly arranged between the nut raceway 26 and the circulating load-bearing raceway 25 along the circumferential direction to form a ball thread transmission mechanism; the ball nut 2 is connected to the stator 6 through an upper bearing assembly 3 and a lower bearing assembly 4, the rotor 5 is arranged between the stator 6 and the ball nut 2, the ball nut 2 is driven to rotate by a motor, driving the screw 33 to make a linear motion, and an upper shell 8 for setting a motor is provided on the upper end of the ball nut 2. The reverse ball screw pair makes the circulation structure on the screw 33. When running, the motor directly drives the ball nut 2, and the rotational motion of the ball nut 2 is converted into the linear motion of the screw 33. When converting the rotational motion of the motor into linear motion, the steel ball 24 acts as a rolling element between the screw and the nut, reducing friction and improving efficiency. This design realizes the effective coupling of the output shaft of the reverse ball screw assembly with the motor motion, realizing efficient power transmission. It is small in size and high in efficiency. The ball screw pair can be integrated into the drive system in a limited space and provide higher precision and response speed. The hollow reverse ball screw makes the entire system structure more compact and reduces space occupation compared to traditional designs.

[0026] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 As shown, the stator 6 has a rigid shell outside, and an upper isolator 9 and a lower isolator 10 are respectively arranged at the upper and lower ends between the stator 6 and the shell. The key components of the system are covered with a rigid shell, and the internal isolator is used to reduce vibration transmission. The structural strength of the system is enhanced, and the overall durability and impact resistance are improved. In addition, the isolator effectively reduces vibration transmission, especially in complex road conditions, and significantly improves riding comfort.

[0027] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 and Figure 3 As shown, the screw 33 is evenly distributed with a plurality of ball spline grooves 27 on the circumference, and a ball spline 11 is connected between the screw 33 and the rigid housing. The ball spline 11 provides an anti-rotation function to prevent the screw part from rotating relative to the housing, ensuring that only axial movement is performed. In addition, the spline groove is combined with the ball screw without interfering with each other. The combination of the ball spline improves the torque transmission efficiency and rigidity of the system, while reducing wear and extending the life of the system.

[0028] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 As shown, an upper vernier magnetic ring 14 is provided at the upper end of the damper 1, and a lower vernier magnetic ring 13 is provided between the damper piston 15 and the mounting frame 16. The use of double vernier magnetic rings to monitor the compression of the spring assembly and the position of the linear actuator 7 improves the real-time control capability of the system, and can make dynamic adjustments based on precise position information and load feedback to ensure that the system is always in the best state.

[0029] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 As shown, a top connection shell 20 is provided on the upper part of the linear actuator 7, and a position sensor 19 is provided inside the linear actuator 7. The upper end of the position sensor 19 is installed in the top connection shell 20, and the lower end is connected to a position sensor rod 22, which extends downward into the mounting frame 16; a load sensor 23 is provided on the top connection shell 20. The position sensor 19 can measure the position change of the mounting frame 16 to control the response of the suspension system. The load sensor 23 is used to monitor the load change of the system in real time.

[0030] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 As shown, an encoder 21 is disposed in the upper shell 8 to measure the rotation position and speed of the lead screw 33 and feed the information back to the control system to ensure accurate motion control.

[0031] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 1 As shown, the spring assembly is an air spring 18, the upper end of the air spring 18 is connected to the lead screw 33 through the upper spring mounting seat 12, and the lower end of the air spring 18 is connected to the mounting frame 16 through the lower spring mounting seat 17. The air spring 18 has good high-frequency vibration absorption and sound insulation performance, and the stiffness of the air spring 18 can be selected to be low, which can reduce the natural frequency of the vehicle.

[0032] In some other specific embodiments of the present invention, the rest is the same as the above embodiment, except that, Figure 4 As shown, the spring assembly is a coil spring 34, the upper end of the coil spring 34 is connected to the lead screw 33 through the upper spring mounting seat 12, and the lower end of the coil spring 34 is connected to the mounting frame 16 through the lower spring mounting seat 17. The coil spring 34 can be used as an alternative to the air spring, which has the characteristics of simple structure, convenient manufacturing and wide application.

[0033] like Figure 5As shown, the present invention further provides an active suspension system based on the above embodiments, which includes the active suspension structure described in any of the above embodiments, and a controller 28; the active suspension structure has four groups, which are respectively arranged below the body 29 at the left front wheel, the body 30 at the right front wheel, the body 31 at the left rear wheel, and the body 32 at the right rear wheel, and are connected to the corresponding wheel hub through the mounting frame 16; the sensor on each group of active suspension structures is connected to the controller 28. In the system, a sensor is provided at each tire, which is responsible for real-time monitoring of the height change between the wheel and the body. The linear actuator 7 accurately controls the inflation, deflation or compression state of the air spring or the coil spring, directly affecting the distance between the wheel and the body and the rigidity of the spring, thereby achieving height adjustment and comfort optimization of the vehicle. The spring assembly and damper of each tire play a passive adjustment role in the system. They naturally respond to road unevenness, acceleration and braking as the vehicle moves, providing appropriate support and shock absorption effects to maintain the stability of the vehicle. The controller 28 processes the data from the sensors, comprehensively analyzes the dynamic state of the vehicle, and sends signals to the linear actuator 7 according to the preset control strategy to actively adjust the vehicle height and the stiffness of the air or coil spring. At the same time, it also monitors the passive response of the spring assembly and damper to ensure that the overall suspension system provides the best vehicle stability and comfort under various road conditions.

[0034] Of course, the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the main technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. An active suspension structure, characterized in that: Includes linear actuator, spring assembly, damper and mounting bracket; The linear actuator is a ball screw subassembly, which is a hollow structure and is driven by a motor to perform linear motion; The upper end of the spring assembly is connected to the ball screw assembly, and the lower end of the spring assembly is connected to the mounting frame, and the spring assembly is stretched or compressed as the ball screw assembly moves; The damper is arranged in the hollow structure inside the linear actuator, and a damper piston is arranged at the front end of the damper; The upper end of the mounting frame is connected to the damper piston, the middle of the mounting frame is connected to the spring assembly, and the bottom of the mounting frame is provided with a mounting hole for connecting the wheel hub; the bottom mounting frame moves up and down with the extension and compression of the spring assembly; the mounting frame is squeezed by the vehicle body to push the damper piston upward and compress the spring assembly.

2. The active suspension structure according to claim 1, characterized in that: The ball screw subassembly is a reverse ball screw subassembly; it includes steel balls, ball nuts, a screw that also serves as an output shaft, a rotor and a stator; an open spiral nut raceway is provided on the inner surface of the ball nut, the ball nut is sleeved on the screw, and a circulating load-bearing raceway is provided on the outer surface of the rear end of the screw; the steel balls are evenly arranged between the nut raceway and the circulating load-bearing raceway along the circumferential direction to form a ball thread transmission mechanism; the ball nut is connected to the stator through an upper bearing assembly and a lower bearing assembly, the rotor is arranged between the stator and the ball nut, the ball nut is driven to rotate by a motor, driving the screw to make a linear motion, and an upper shell for setting the motor is provided at the upper end of the ball nut.

3. The active suspension structure according to claim 2, characterized in that: The stator is provided with a rigid shell outside, and an upper isolator and a lower isolator are respectively arranged at the upper and lower ends between the stator and the shell.

4. The active suspension structure according to claim 3, characterized in that: A plurality of ball spline grooves are evenly distributed on the circumference of the lead screw, and a ball spline is connected between the lead screw and the rigid shell.

5. An active suspension structure according to claim 1 or 2, characterized in that: An upper vernier magnetic ring is arranged at the upper end of the damper, and a lower vernier magnetic ring is arranged between the damper piston and the mounting frame.

6. An active suspension structure according to claim 1 or 2, characterized in that: A top connecting shell is arranged on the upper part of the linear actuator, a position sensor is arranged inside the linear actuator, the upper end of the position sensor is installed in the top connecting shell, the lower end is connected to a position sensor rod, and the position sensor rod extends downward into the mounting frame; a load sensor is arranged on the top connecting shell.

7. The active suspension structure according to claim 2, characterized in that: An encoder is arranged in the upper shell.

8. The active suspension structure according to claim 2, characterized in that: The spring assembly is an air spring, the upper end of the air spring is connected to the lead screw through an upper spring mounting seat, and the lower end of the air spring is connected to the mounting frame through a lower spring mounting seat.

9. The active suspension structure according to claim 2, characterized in that: The spring assembly is a coil spring, the upper end of the coil spring is connected to the lead screw through an upper spring mounting seat, and the lower end of the coil spring is connected to the mounting frame through a lower spring mounting seat.

10. An active suspension system, characterized in that: It includes the active suspension structure described in any one of claims 1 to 9 above, and a controller; the active suspension structure has four groups, which are respectively arranged under the body at the left front wheel, the body at the right front wheel, the body at the left rear wheel, and the body at the right rear wheel, and are connected to the corresponding wheel hubs through a mounting frame; the sensors on each group of active suspension structures are connected to the controller.

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