A stiffness-adjustable coil spring and a stiffness adjustment method

Abstract

The present application relates to the technical field of spring, in particular to a kind of stiffness adjustable coil spring and stiffness adjusting method.The device includes coil spring, the coil spring wire of the coil spring is hollow structure;Conductive fluid, the conductive fluid is arranged in the hollow structure of coil spring, and viscosity change occurs directly or under the action of magnetic field after electrification;First electrode, the first electrode is arranged at one end of coil spring;Second electrode, the second electrode is arranged at the other end of coil spring;Electric control device, the electric control device and first electrode, conductive fluid and second electrode are electrically connected to form loop, for regulating the current in the loop.The stiffness adjusting method adopts coil spring device, is suitable for being installed on the shock absorber of vehicle suspension, and the steering and driving comfort of driving vehicle under different road conditions are improved by adjusting the stiffness of coil spring.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of spring, in particular to a stiffness-adjustable coil spring and a stiffness adjusting method. BACKGROUND

[0002] Traditional car suspension systems mostly use coil springs for damping vibration, different spring stiffness provides different suspension stiffness, bringing different handling and ride comfort feeling. The elastic coefficient of conventional springs, i.e. stiffness, is fixed and does not have the function of adjusting suspension stiffness, which cannot provide high ride comfort in different road conditions.

[0003] Patent publication No. "CN202251596U" discloses an adjustable stiffness coil spring, which comprises a coil spring and a ring-shaped external electromagnet or a columnar internal electromagnet. The spring wire of the coil spring is composed of a hollow tube, and a liquid or grease is encapsulated in the hollow tube. The outer diameter of the coil spring is smaller than the inner diameter of the ring-shaped external electromagnet and leaves a gap, the coil spring is placed in the ring-shaped external electromagnet or the inner diameter of the coil spring is larger than the outer diameter of the columnar internal electromagnet and leaves a gap, and the columnar internal electromagnet is placed in the coil spring. The device changes the viscosity of the liquid or grease by controlling the power to adjust the magnetic force of the electromagnet. The electromagnet must be used, the spring device needs a buffering distance, i.e. an expansion gap, for automobile damping, and the electromagnet cannot be expanded, so the spring device cannot adapt to be installed on a shock absorber to provide adjustable stiffness for the suspension. SUMMARY

[0004] The main purpose of the present application is to solve the problems in the background art and provide a stiffness-adjustable coil spring and a stiffness adjusting method which can be installed on a shock absorber.

[0005] The technical solution adopted by the present application is as follows: a stiffness-adjustable coil spring, comprising,

[0006] The spring wire of the coil spring is a hollow structure;

[0007] A conductive fluid is arranged in the hollow structure of the coil spring and can change in viscosity directly or under the action of a magnetic field after being electrified;

[0008] A first electrode is arranged at one end of the coil spring;

[0009] A second electrode is arranged at the other end of the coil spring;

[0010] An electric control device is electrically connected with the first electrode, the conductive fluid and the second electrode to form a loop for regulating the current in the loop.

[0011] Further, the helical spring is sleeved on the shock absorber, one end of the helical spring is fixed on the fixed end of the shock absorber, and the other end is fixed on the movable end of the shock absorber.

[0012] Further, the first electrode comprises an electrode connecting sheet arranged at one end of the helical spring, and an excitation coil arranged at the end of the spring wire and electrically connected with the electrode connecting sheet and the electric control device at two ends, respectively.

[0013] Further, an insulating layer is arranged in the hollow structure of the helical spring, and is used for separating the spring wire and the conductive fluid.

[0014] Further, the conductive fluid comprises a conductive magnetic fluid and a metal-water combination.

[0015] Further, the sensor assembly is used for collecting regulation information, and the electric control device can regulate the current in the loop according to the regulation information, so as to adjust the rigidity of the helical spring.

[0016] Further, the regulation information comprises at least one of a throttle opening degree, a suspension vibration frequency, a steering wheel rotation angle, a vehicle acceleration or a vehicle speed.

[0017] Further, the regulation information comprises the vehicle acceleration, and the electric control device automatically regulates the current in the loop when the vehicle acceleration is greater than or equal to a preset acceleration threshold value; the current in the loop increases with the increase of the vehicle acceleration value.

[0018] Further, the vehicle acceleration comprises a shock absorber acceleration; the shock absorber acceleration comprises at least one of a vertical acceleration, a longitudinal acceleration or a lateral acceleration; the vertical acceleration comprises an acceleration of vertical stretching of the shock absorber or an acceleration of vertical movement of the fixed end of the shock absorber.

[0019] Further, the regulation information comprises the suspension vibration frequency, and the electric control device regulates the current in the loop according to the frequency segment where the suspension vibration frequency is located; each of the frequency segments corresponds to a corresponding current in the loop.

[0020] Further, the regulation information collected by the sensor assembly comprises the steering wheel rotation angle and the throttle opening degree; the electric control device increases or decreases the current in the loop when the steering wheel rotation angle is constant and the throttle opening degree increases, or the throttle opening degree is constant and the steering wheel rotation angle increases, or the steering wheel rotation angle and the throttle opening degree increase simultaneously.

[0021] Further, the regulation information is provided with a weighting coefficient, when the regulation information comprises multiple items, the electric control device adjusts the current in the loop according to a comprehensive regulation value, and the comprehensive regulation value comprises a sum of products of current values corresponding to each item of regulation information and corresponding weighting coefficients.

[0022] Further, the electric control device adjusts the current of the loop with multiple gears, and the comprehensive control value corresponds to different gears of the loop current.

[0023] Further, the electric control device adjusts the current of the loop with multiple gears, and the gears correspond to percentages of the maximum current, including 0%, 25%, 50%, 75%, and 100%.

[0024] Another aspect of the present application also provides a stiffness adjustment method of the stiffness-adjustable coil spring, using the stiffness-adjustable coil spring provided by the present application, the stiffness adjustment method comprises,

[0025] The control information of the loop current controlled by the electric control device is collected.

[0026] It is judged whether the control information meets the control condition of the electric control device controlling the loop current.

[0027] When the control information meets the control condition, the electric control device automatically controls the current in the loop according to the control information.

[0028] Further, the control information includes at least one of the throttle opening, the suspension vibration frequency, the steering wheel angle, the vehicle acceleration, or the vehicle speed.

[0029] Further, the judgment of whether the control information meets the control condition of the electric control device controlling the loop current includes judging whether the vehicle acceleration is greater than or equal to a preset acceleration threshold, and if so, judging that the control information meets the control condition.

[0030] Further, the judgment of whether the control information meets the control condition of the electric control device controlling the loop current includes judging whether the frequency segment of the suspension vibration frequency corresponds to the loop current, and if not, judging that the control information meets the control condition.

[0031] Further, the judgment of whether the control information meets the control condition of the electric control device controlling the loop current includes judging whether the throttle opening increases when the steering wheel angle is constant, or whether the steering wheel angle increases when the throttle opening is constant, or whether the steering wheel angle and the throttle opening increase at the same time, and if so, judging that the control information meets the control condition.

[0032] Further, the electric control device automatically controls the current in the loop according to the control information, including automatically controlling the loop current when the vehicle acceleration is greater than or equal to a preset acceleration threshold; the loop current increases with the increase of the vehicle acceleration value.

[0033] Further, the electric control device automatically controls the current in the loop according to the corresponding regulation information, including regulating the loop current according to the frequency segment where the suspension vibration frequency is located; each frequency segment corresponds to a corresponding loop current.

[0034] Further, the electric control device automatically controls the current in the loop according to the corresponding regulation information, including increasing or decreasing the loop current when the steering wheel angle is constant and the accelerator opening is increased, or the accelerator opening is constant and the steering wheel angle is increased, or the steering wheel angle and the accelerator opening are simultaneously increased.

[0035] The beneficial effects of the present application include: 1. The helical spring device is electrically connected to the helical conductive fluid by the electric control device to form a loop, so that the conductive fluid is energized or changes in viscosity under the action of a magnetic field, thereby changing the stiffness of the helical spring. No electromagnet is needed, and it can be installed on the shock absorber of the vehicle suspension, and the stiffness of the helical spring can be adjusted to improve the comfort of driving the vehicle under different road conditions.

[0036] 2. The first electrode can generate a magnetic field through the excitation coil, and when the conductive fluid is selected as a conductive magnetic fluid, the regulation of the viscosity of the conductive fluid can be enhanced.

[0037] 3. The inner wall of the helical spring guide wire and the conductive fluid are isolated by the insulating layer, which can prevent safety hazards caused by the conduction of the helical spring.

[0038] 4. The sensor assembly can collect regulation information to automatically adjust the current in the circuit, change the viscosity of the conductive fluid, and thereby regulate the stiffness of the helical spring. At least one of the accelerator opening, suspension vibration frequency, steering wheel angle, vehicle acceleration, or vehicle speed is used as regulation information to reflect the action or road condition of the vehicle driving, so as to correspondingly adjust the stiffness of the helical spring to reduce vibration or roll, and improve driving comfort.

[0039] 5. The electric control device of the present application regulates the loop current based on the vehicle acceleration, so that the stiffness of the helical spring can adapt to the acceleration or deceleration action of the vehicle, and reduce the head lifting during acceleration, deceleration or braking.

[0040] 6. Using the shock absorber acceleration as the vehicle acceleration can divide the overall vehicle acceleration into multiple local accelerations, which is convenient for regulating the stiffness of the vehicle suspension. Regulating the stiffness of the helical spring based on the lateral acceleration of the shock absorber can be used to regulate the roll characteristics of the vehicle. Regulating the stiffness of the helical spring based on the longitudinal acceleration of the shock absorber can reduce the bump feeling and enhance the stability.

[0041] 7. The vibration frequency generated by the vehicle driving on different road surfaces is different, and the electric control device of the present application regulates the loop current based on the suspension vibration frequency, so that the stiffness of the helical spring can adapt to the corresponding road conditions and improve the driving stability.

[0042] 8. The electronic control device of the present invention regulates the circuit current based on the steering wheel angle and throttle opening, which can adjust the steering characteristics of the vehicle. The adjusted coil spring stiffness can tend to understeer, resulting in good steering characteristics and safety; the adjusted coil spring stiffness can tend to oversteer, which is beneficial for drifting.

[0043] 9. By setting weighting coefficients, the magnitude of the integrated control circuit current can be adjusted when the control information includes multiple information items, making the stiffness of the helical spring more in line with driving needs, thereby improving driving performance and comfort.

[0044] 10. When an electromagnetic fluid is energized inside a helical spring, it forms a coil that generates a magnetic field. Under the influence of the magnetic field, the viscosity of the electromagnetic fluid changes, thereby adjusting the stiffness of the helical spring. When a metal-water composite is energized, its own viscosity is directly changed, making it easy to use current to control the viscosity and adjust the stiffness of the helical spring.

[0045] 11. The method for adjusting the stiffness of the adjustable helical spring of the present invention fully utilizes the characteristics of the adjustable helical spring of the present invention, and the adjustment is simple and convenient; based on the material properties of the helical spring itself as the basic stiffness, the stiffness of the helical spring can be adjusted by adjusting the current after energizing.

[0046] The adjustable stiffness helical spring and stiffness adjustment method of the present invention can be installed on vehicle suspension to adjust the stiffness of the suspension. The stiffness of the helical spring is adjusted by changing the viscosity of the conductive fluid by adjusting the magnitude of the current, thereby adjusting the stiffness of the suspension and thus adjusting the driving comfort. It is simple to operate and use and has great promotional value. Attached Figure Description

[0047] Fig. 1 : A schematic diagram of the adjustable stiffness helical spring device of the present invention;

[0048] Fig. 2 Schematic diagram of a helical spring structure;

[0049] Fig. 3 Schematic diagram of a shock absorber connected by a helical spring;

[0050] Wherein: 1—coil spring; 11—sealed end cap; 2—first electrode; 21—electrode connecting piece; 3—second electrode; 4—electrical control device; 5—sensor assembly; 6—fixed tower top; 7—spring support plate; 8—vibration damper. Detailed Implementation

[0051] Embodiments of the present invention are described in detail below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0052] In the description of the present application, it needs to be understood that the terms "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0053] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features referred to. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] The present application will be further described in detail below in conjunction with the drawings and specific embodiments.

[0055] The present application relates to a stiffness-adjustable helical spring, which can be installed on a shock absorber of a vehicle to provide adjustable stiffness for a suspension, the stiffness of the helical spring is adjusted by controlling the size of the current forming a circuit with a conductive fluid by an electric control device to change the viscosity of the conductive fluid, so as to adjust the stiffness of the suspension, thereby improving the driving comfort, which is simple to operate and use, and has great popularization value.

[0056] A stiffness-adjustable helical spring, as shown in Figs. 1-3 comprises a helical spring 1, a conductive fluid, a first electrode 2, a second electrode 3 and an electric control device 4, the spring wire of the helical spring 1 is a hollow structure, the hollow structure forms a spiral pipeline in the helical spring 1; the conductive fluid is arranged in the hollow structure of the helical spring 1, and the viscosity of the conductive fluid can be directly changed after being electrified or changed under the action of a magnetic field generated by the spiral coil of the conductive fluid; the first electrode 2 is arranged at one end of the helical spring 1; the second electrode 3 is arranged at the other end of the helical spring 1; the electric control device 4 is electrically connected with the first electrode 2, the conductive fluid and the second electrode 3 to form a series circuit, and is used for controlling the current in the circuit; when the viscosity of the conductive fluid changes, the elastic coefficient of the helical spring 1, i.e. the stiffness, also changes, and the stiffness of the helical spring 1 can be adjusted by controlling the current in the above-mentioned circuit by the electric control device 4, without the need for a non-stretchable electromagnet, which can be adapted to be installed on a vehicle suspension to adjust the stiffness of the suspension and improve the driving comfort.

[0057] In one embodiment, as shown in Fig. 3As shown, the coil spring 1 is sleeved on the shock absorber 8, one end of the coil spring 1 is fixedly connected to the fixed end of the shock absorber 8, and the other end is fixedly connected to the movable end of the shock absorber 8. Specifically, the fixed end of the shock absorber 8 is fixedly provided with a spring support plate 7, and the movable end of the shock absorber 8 is provided with a fixed tower top 6, which can be a plate-shaped structure. The coil spring 1 is sleeved on the shock absorber 8 and is fixedly connected to the spring support plate 7 and the fixed tower top 6 at both ends, respectively. The electric control device 4 is fixedly arranged on the fixed tower top 6 or the spring support plate 7. The coil spring 1 device is fixedly connected with the shock absorber 8 as a whole, which is convenient to install on the suspension in the assembly process.

[0058] In further embodiments, the coil spring 1 device of the present application further comprises a sensor assembly 5, such as Fig. 1 、 Fig. 3 As shown schematically, the sensor assembly 5 is used to collect control information; the electric control device 4 can control the current in the loop according to the control information; the control information includes at least one of the throttle opening, the suspension vibration frequency, the steering wheel angle, the vehicle acceleration or the vehicle speed, that is, any one or more of the throttle opening, the suspension vibration frequency, the steering wheel angle, the vehicle acceleration, and the vehicle speed can be used as control information. The control information collected by the sensor assembly 5 can be used as the basis for the electric control device 4 to control the current, and the electric control device 4 can automatically adjust the stiffness of the coil spring 1; at least one of the throttle opening, the suspension vibration frequency, the steering wheel angle, the vehicle acceleration or the vehicle speed as control information can reflect the action or road conditions of the vehicle running, so as to correspondingly adjust the stiffness of the coil spring 1 to reduce vibration and improve driving comfort.

[0059] On the basis of collecting control information based on the sensor assembly 5, the control information collected by the sensor assembly 5 includes vehicle acceleration, which includes vehicle lateral acceleration (in the vehicle width direction), vehicle longitudinal acceleration (in the vehicle length direction) and vehicle vertical acceleration (in the vehicle height direction), and an acceleration sensor can be used to collect vehicle acceleration; the electric control device 4 automatically controls the increase of the loop current when the vehicle acceleration is greater than or equal to a preset acceleration threshold; the loop current increases with the increase of the vehicle acceleration value; when the vehicle accelerates, the load is transferred to the rear axle, so that the coil spring 1 of the rear suspension will produce corresponding compression deformation, and the smaller the stiffness of the coil spring 1, the greater the compression deformation, and the more serious the acceleration lift phenomenon of the vehicle. Based on the vehicle longitudinal acceleration signal collected by the sensor assembly 5, the electric control device 4 automatically adjusts the stiffness of the coil spring 1 of the rear suspension to reduce the discomfort brought by the acceleration lift; when the vehicle brakes, the load is transferred to the front axle, so that the coil spring 1 of the front suspension will produce corresponding compression deformation, and the smaller the stiffness of the coil spring 1, the greater the compression deformation, and the more serious the braking nod phenomenon of the vehicle. The electric control device 4 controls the above-mentioned loop current based on the vehicle acceleration, which can make the stiffness of the coil spring 1 adapt to the acceleration or deceleration action of the vehicle, and reduce the acceleration lift, deceleration or braking nod of the vehicle.

[0060] On the basis of the control information including vehicle acceleration, the vehicle acceleration includes damper acceleration; the damper acceleration includes at least one of vertical acceleration, longitudinal acceleration and lateral acceleration; wherein the vertical acceleration includes any one of the acceleration of the vertical expansion of the damper 8 and the acceleration of the vertical movement of the fixed end of the damper 8. A plurality of dampers 8 are provided on the vehicle, and the overall vehicle acceleration can be divided into a plurality of local accelerations by taking the damper acceleration as the vehicle acceleration, which is convenient for separately controlling the stiffness of each side of the vehicle suspension. The stiffness of the coil spring 1 controlled based on the lateral acceleration of the damper 8 can be used to control the roll characteristics of the vehicle, so as to avoid the influence of vehicle roll on driving stability and cause the body to sway left and right. The steering characteristics of the vehicle can be adjusted according to the stiffness of the coil spring 1 controlled according to the lateral acceleration of the damper. For example, when the vehicle is turning or changing lanes, the load on part of the dampers 8 increases, which causes the deformation to increase and causes the vehicle to roll. The stiffness of the corresponding coil spring 1 is automatically controlled based on the damper longitudinal acceleration, which can reduce the bump feeling and enhance the stability.

[0061] On the basis of the control information collected by the sensor assembly 5, the control information collected by the sensor assembly 5 includes the suspension vibration frequency, which can be collected by using a vibration sensor. The control device 4 controls the loop current based on the suspension vibration frequency; specifically, the control device 4 controls the loop current according to the frequency section where the suspension vibration frequency is located; each of the above frequency sections corresponds to a corresponding loop current; the vibration frequencies generated by the vehicle driving on different road surfaces are different, and the control device 4 of the present application automatically controls the loop current based on the suspension vibration frequency, which can make the stiffness of the coil spring 1 adapt to the corresponding road conditions and improve the driving stability.

[0062] In an embodiment, the frequency section includes 0-3Hz, 3-6Hz, 6-23Hz, 23-30Hz, 30-60Hz and the like. Each frequency section corresponds to the size of the corresponding loop current, and the size of the loop current corresponding to each frequency section can be tested and calibrated. The 0-3Hz frequency section corresponds to the driving floating feeling, the 3-6Hz frequency section corresponds to the driving swinging feeling, the 6-23Hz frequency section corresponds to the driving buffeting feeling, the 23-30Hz frequency section corresponds to the driving flutter feeling, and the 30-60Hz frequency section corresponds to the driving tingling feeling. For example, the suspension vibration frequency is mainly 4.5Hz, and the frequency section is 3-6Hz. When the size of the loop current is not in the current size corresponding to the 3-6Hz frequency section, the control device 4 controls the current size to be the current size corresponding to the 3-6Hz frequency section, which improves the comfort of driving on different road conditions.

[0063] On the basis of collecting the regulation information based on the sensor assembly 5, the regulation information collected by the sensor assembly 5 includes the steering wheel angle and the throttle opening, and the electric control device 4 regulates the loop current according to the steering wheel angle and the throttle opening; the steering wheel angle can be collected by using an angle sensor; the throttle opening can be obtained by using a throttle opening sensor, and the throttle opening sensor can have the function of obtaining the throttle opening information, and in practice, the travel of the accelerator pedal or the proportion of the travel to the maximum travel can be used as the throttle opening, or the throttle opening can be directly obtained from the vehicle system. The electric control device 4 regulates the loop current according to the steering wheel angle and the throttle opening, and adjusts the steering characteristics of the vehicle; specifically, when the steering wheel angle is constant and the throttle opening is increased or the throttle opening is constant and the steering wheel angle is increased or the steering wheel angle and the throttle opening are increased at the same time, the loop current is increased or decreased. For example, in a steady-state curve, the steering wheel angle is kept constant and the throttle opening is gradually increased, or the vehicle speed is kept constant and the steering wheel angle is gradually increased, or the steering wheel angle and the throttle opening are simultaneously increased, and the electric control device 4 automatically adjusts the stiffness of the front and rear suspension coil springs 1 according to the steering wheel angle and the throttle opening, so that the stiffness of the front suspension coil spring 1 of the adjusted vehicle is increased to tend to be insufficient steering, has good steering characteristics and safety, and the stiffness of the front suspension coil spring 1 of the adjusted vehicle is decreased to tend to be excessive steering, which is beneficial to drifting and adapts to different driving needs.

[0064] In addition, in order to better adjust the steering characteristics, the vehicle acceleration and / or the vehicle speed can be added as regulation information on the basis of using the throttle opening and the steering wheel angle as regulation information. When the throttle opening is constant, the speed of the vehicle can be different, and the speed of the vehicle can be detected by using a speed sensor. The addition of the speed information can make the stiffness of the adjusted coil spring 1 meet the steering at the speed; the vehicle acceleration is related to the throttle opening, and the vehicle acceleration (such as vehicle lateral acceleration) can be added to comprehensively regulate the stiffness of the coil spring 1, so that it meets different driving needs.

[0065] On the basis of collecting the regulation information based on the sensor assembly 5, the regulation information collected by the sensor assembly 5 includes the vehicle speed information, and the speed sensor can be used to collect the vehicle speed information, and the speed sensor can be a linear speed sensor and an angular speed sensor. The speed is calculated by combining the rotational speed or the tire size, and the electric control device 4 regulates the loop current according to the vehicle speed. When the vehicle speed is greater, the vehicle receives greater vibration and impact under the same road conditions, and the stiffness of the coil spring 1 corresponding to the vehicle speed can reduce the vibration amplitude of the vehicle and improve the driving stability.

[0066] On the basis of collecting the regulation information based on the sensor assembly 5, in some embodiments, the regulation information is provided with a weighting coefficient, the weighting coefficient can be calibrated according to the driving mode, when the regulation information includes multiple items, the electric control device 4 adjusts the loop current according to a comprehensive regulation value, the comprehensive regulation value includes the sum of the product of the current value corresponding to each item of regulation information and the corresponding weighting coefficient. Preferably, the sum of the weighting coefficients of each item of regulation information is 1. For example, the regulation information includes vehicle acceleration and suspension vibration frequency, and their respective weighting coefficients are 0.7 and 0.3, respectively, wherein the loop current value corresponding to the vehicle acceleration is A1, and the loop current value corresponding to the frequency segment where the suspension vibration frequency is located is A2, then the comprehensive regulation value is A0=0.7A1+0.3A2, and the electric control device 4 determines the final loop current according to the comprehensive regulation value A0.

[0067] On the basis of providing the regulation information with a weighting coefficient, the electric control device adjusts the current of the loop with multiple gears, and the comprehensive regulation value obtained by weighting and solving multiple regulation information corresponds to different gears of the loop current.

[0068] In some embodiments, the conductive fluid includes a conductive magnetic fluid and a metal-water complex, i.e. the conductive fluid can be a conductive magnetic fluid and / or a metal-water complex and / or other conductive fluid whose viscosity changes (related to current) when conducting electricity; the conductive magnetic fluid forms a coil in the helical spring 1, generates a magnetic field after being electrified, and the magnetism of the conductive magnetic fluid is affected by the magnetic field to increase the viscosity of the conductive magnetic fluid, so as to change the stiffness of the helical spring 1; the metal-water complex has the characteristics that the atomic bonds on the metal surface will be strengthened after being electrified, and the hardness will increase; cutting off or reducing the current will weaken the atomic bonds, and the material will become softer, the resistance to damage will be stronger, and the ductility will be better, so as to quickly adjust the stiffness of the helical spring 1 as the conductive fluid.

[0069] In some embodiments, the first electrode 2 is specifically described, the first electrode 2 includes an electrode connecting piece 21 and an excitation coil, the electrode connecting piece 21 is arranged at one end of the helical spring 1 to connect the conductive fluid, and the excitation coil is arranged at the end of the spring wire and the two ends of the excitation coil are connected with the electrode connecting piece and the electric control device 4; the second electrode 3 can be substantially the same as the first electrode 2 and also includes an electrode connecting piece 21 and an excitation coil; after being electrified, the excitation coil can generate a magnetic field, and when the conductive magnetic fluid is used as the conductive fluid, the viscosity of the conductive magnetic fluid can be increased. In specific use, the two ends of the hollow spring wire are provided with sealed end covers 11, the electrode connecting pieces 21 are fixedly arranged on the sealed end covers 11 to contact and connect the conductive fluid, the excitation coils are fixedly arranged on the electrode connecting pieces 21, and the excitation coils are in a tangential or approximately tangential state with the helical direction of the spring wire.

[0070] In some embodiments, an insulating layer is arranged in the hollow structure of the coil spring 1 to insulate the coil spring 1 wire from the conductive fluid; the insulating layer is fixedly connected to the hollow structure, and both the hollow structure and the insulating layer can be cylindrical structures; the insulating layer can prevent the coil spring 1 from conducting electricity and causing safety hazards.

[0071] It is worth noting that the electric control device 4 can gradually adjust the current size in a smooth manner or select and adjust the current size in a gear mode; when the gear mode is adopted, the electric control device 4 is calibrated with multiple gears, and the gear corresponds to a percentage range of the maximum current value, which can be any percentage therebetween, including but not limited to 0%, 25%, 50%, 75%, and 100%.

[0072] Another aspect of the present application also provides a stiffness adjustment method for a stiffness-adjustable coil spring, which uses the stiffness-adjustable coil spring provided by the present application, and the stiffness adjustment method comprises,

[0073] S1, collecting control information for triggering the electric control device 4 to control the current in the circuit;

[0074] S2, determining whether the control information meets the control condition of the electric control device 4 for controlling the current in the circuit;

[0075] S3, when the control information meets the control condition, the electric control device 4 automatically controls the current in the circuit according to the control information.

[0076] According to the stiffness adjustment method for the stiffness-adjustable coil spring provided by the present application, the control information includes at least one of the throttle opening, the suspension vibration frequency, the steering wheel angle, the vehicle acceleration, or the vehicle speed;

[0077] According to the stiffness adjustment method for the stiffness-adjustable coil spring provided by the present application, in the S2 step, determining whether the control information meets the control condition of the electric control device 4 for controlling the current in the circuit includes determining whether the vehicle acceleration is greater than or equal to a preset acceleration threshold, and if so, determining that the control information meets the control condition.

[0078] According to the stiffness adjustment method for the stiffness-adjustable coil spring provided by the present application, in the S2 step, determining whether the control information meets the control condition of the electric control device 4 for controlling the current in the circuit includes determining whether the frequency segment where the suspension vibration frequency is located corresponds to the current in the circuit, and if not, determining that the control information meets the control condition.

[0079] According to the stiffness-adjustable helical spring stiffness adjusting method provided by the application, in the S2 step, it is judged whether the control information satisfies the control condition of the electric control device 4 controlling the loop current, including judging whether the accelerator opening degree is increased when the steering wheel angle is constant or the steering wheel angle is increased when the accelerator opening degree is constant or the steering wheel angle and the accelerator opening degree are simultaneously increased, and if yes, it is judged that the control information satisfies the control condition.

[0080] According to the stiffness-adjustable helical spring stiffness adjusting method provided by the application, in the S3 step, the electric control device 4 automatically controls the current in the loop according to the control information, including automatically controlling the loop current when the vehicle acceleration is greater than or equal to a preset acceleration threshold value; the loop current is increased with the increase of the vehicle acceleration value.

[0081] According to the stiffness-adjustable helical spring stiffness adjusting method provided by the application, in the S3 step, the electric control device 4 automatically controls the current in the loop according to the control information, including controlling the loop current according to the frequency segment where the suspension vibration frequency is located; the frequency segment has a corresponding loop current.

[0082] According to the stiffness-adjustable helical spring stiffness adjusting method provided by the application, in the S3 step, the electric control device 4 automatically controls the current in the loop according to the control information, including increasing or decreasing the loop current when the steering wheel angle is constant and the accelerator opening degree is increased or the accelerator opening degree is constant and the steering wheel angle is increased or the steering wheel angle and the accelerator opening degree are simultaneously increased.

[0083] In actual use, the helical spring 1 device is fixedly sleeved on the shock absorber 8 to fix the two ends of the helical spring 1 to the fixed end and the movable end of the shock absorber 8 respectively; the helical spring 1 device integrated with the shock absorber 8 is installed on the front and rear suspensions of the vehicle; the function sensors of the sensor assembly 5 are connected to the corresponding components to collect the control information, such as arranging the acceleration sensor on the movable end of the shock absorber 8 to collect the acceleration information of the shock absorber 8, connecting the pedal stroke sensor to the accelerator pedal to collect the accelerator opening degree information, connecting the angle sensor to the steering wheel to collect the steering wheel angle information, arranging the vibration sensor on the vehicle suspension to collect the suspension vibration frequency, and arranging the speed sensor to collect the vehicle speed information; the sensor assembly 5 is in communication connection with the electric control device 4, so that the electric control device 4 automatically controls the current size in the loop according to the control information collected by the sensor assembly 5, thereby automatically adjusting the stiffness of each helical spring 1 on each suspension to meet various road conditions or vehicle driving actions.

[0084] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A helical spring with adjustable stiffness, characterized in that: include, A helical spring (1) has a hollow spring wire; the helical spring (1) is sleeved on the damper (8), one end of the helical spring (1) is fixed to the fixed end of the damper (8), and the other end is fixed to the movable end of the damper (8); The conductive fluid is disposed in the hollow structure of the helical spring (1), and its viscosity can change directly or under the action of a magnetic field after being energized. The first electrode (2) is disposed at one end of the helical spring (1); The second electrode (3) is located at the other end of the helical spring (1); An electronic control device (4) is electrically connected to a first electrode (2), a conductive fluid, and a second electrode (3) to form a circuit, which is used to regulate the current in the circuit. The sensor assembly (5) is used to collect control information; the electronic control device (4) can control the current in the circuit according to the control information, thereby adjusting the stiffness of the helical spring (1); The adjustment method for the stiffness-adjustable helical spring includes: Collect and trigger the control device (4) to regulate the current of the circuit; Determine whether the control information meets the control conditions for the circuit current to be controlled by the electronic control device (4); When the control information meets the control conditions, the electronic control device (4) automatically controls the current in the circuit according to the control information.

2. The adjustable stiffness helical spring as described in claim 1, characterized in that: The first electrode (2) includes an electrode connecting piece (21) located at one end of the helical spring (1) and an excitation coil located at the end of the spring wire and electrically connected at both ends to the electrode connecting piece (21) and the electronic control device (4).

3. The adjustable stiffness helical spring as described in claim 1, characterized in that: The hollow structure of the helical spring (1) is provided with an insulating layer to isolate the spring wire from the conductive fluid.

4. A stiffness-adjustable helical spring as described in any one of claims 1-3, characterized in that: The control information includes vehicle acceleration. When the vehicle acceleration is greater than or equal to a preset acceleration threshold, the electronic control device (4) automatically controls the circuit current. The circuit current increases as the vehicle acceleration value increases.

5. A stiffness-adjustable helical spring as described in claim 4, characterized in that: The vehicle acceleration includes shock absorber acceleration; the shock absorber acceleration includes at least one of vertical acceleration, longitudinal acceleration, or lateral acceleration; the vertical acceleration includes the acceleration of vertical extension and contraction of the shock absorber or the acceleration of vertical movement of the fixed end of the shock absorber.

6. The adjustable stiffness helical spring as described in claim 1, characterized in that: The control information includes the suspension vibration frequency. The electronic control device (4) controls the circuit current in segments according to the frequency of the suspension vibration frequency. Each frequency segment corresponds to a corresponding circuit current.

7. The adjustable stiffness helical spring as described in claim 1, characterized in that: The control information includes steering wheel angle and throttle opening; the electronic control device (4) increases or decreases the circuit current when the steering wheel angle is constant and the throttle opening is increased, or the throttle opening is constant and the steering wheel angle is increased, or the steering wheel angle and throttle opening are increased simultaneously.

8. The adjustable stiffness helical spring as described in claim 1, characterized in that: The control information is provided with a weighting coefficient. When the control information includes multiple items, the electronic control device (4) adjusts the circuit current according to the comprehensive control value. The comprehensive control value includes the sum of the products of the current value corresponding to each control information and the corresponding weighting coefficient.

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