A variable stiffness and damping automotive self-tuning electromagnetic suspension

Abstract

The application discloses a variable stiffness and damping automobile self-tuning electromagnetic suspension, which comprises a stator shell, end covers fixedly connected to both ends of the stator shell and a mover inner core; the mover inner core is movably installed in the stator shell, two groups of coils are arranged on the mover inner core, and a plurality of tooth-shaped structures are arranged on the stator shell and the mover inner core on the left and right sides of each group of coils; a conductive copper ring is arranged at the inner wall of the stator shell on the side of one group of coils; linear bearings and supporting springs are sleeved on both ends of the mover inner core; one end of the supporting spring is fixed to the end cover, and the other end is directed to the shaft shoulder of the mover inner core; the end of the mover inner core on the side of the conductive copper ring is led out from the same side end cover and connected with a knuckle bearing, and the end cover on the other side is connected with the knuckle bearing. The application introduces two groups of electromagnetic coils to control the magnetic field intensity of electromagnetic springs and electromagnetic dampers, so that the stiffness and damping of the shock absorber can be independently tuned.

Description

Technical Field

[0001] This invention relates to the field of active electromagnetic suspension technology for automobiles, specifically to a variable stiffness damping self-tuning electromagnetic suspension for automobiles. Background Technology

[0002] Traditional suspension systems mostly consist of hydraulic dampers and air spring shock absorbers, both of which suffer from poor vibration isolation capabilities and lack of adaptive adjustment. In existing technologies, most shock absorbers use fixed damping or stiffness settings, which may not provide optimal ride comfort when dealing with different road conditions and driving modes. Chinese Patent Publication No. CN118088618A discloses a variable-load magnetoelectric coupling quasi-zero stiffness vibration isolator for vehicles, comprising a static balance position actuation mechanism, an additional air chamber mechanism, an air spring mechanism, and a support shaft. The negative stiffness can be adjusted within a certain range, which, combined with the positive stiffness changes of the air spring mechanism, allows the entire vibration isolation system to achieve optimal low-frequency vibration isolation characteristics within a certain load range. The additional air chamber mechanism and the air spring mechanism work together to achieve two levels of adjustability, generating two stiffness curves, and the frequency characteristics of the air spring mechanism can be changed by altering the opening of the solenoid valve. However, a drawback of this method is that the damping cannot be adjusted, thus failing to further improve ride comfort.

[0003] Chinese Patent Publication No. CN116146637A discloses a damping adjustment method for an electromagnetic shock absorber, comprising: reading scale values ​​on a non-uniform scale at a first set time interval to obtain a first scale value and a second scale value; calculating and outputting a first control current to a first electromagnetic component based on the first set time interval, the first scale value, and the second scale value; and outputting a second control current to a second electromagnetic component. The first control current and the second control current are used to generate a first force between the first electromagnetic component and the second electromagnetic component, thereby adjusting the damping of the shock absorber. However, a drawback of this method is that it cannot adjust the stiffness.

[0004] Based on the above existing technologies, it can be seen that although electromagnetic related technologies are also applied to shock absorbers, it is still impossible to actively adjust the stiffness and damping of the shock absorber simultaneously. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this application proposes a variable stiffness and damping self-tuning electromagnetic suspension for automobiles. Two sets of electromagnetic coils are introduced to control the magnetic field strength of the electromagnetic spring and the electromagnetic damper respectively, thereby realizing independent tuning of the stiffness and damping of the shock absorber.

[0006] The technical solution adopted in this invention is as follows:

[0007] A variable stiffness and damping self-tuning electromagnetic suspension for automobiles, comprising:

[0008] Stator housing,

[0009] End caps that are fixedly connected to both ends of the stator housing;

[0010] The mover core is movably installed inside the stator housing. The mover core is equipped with two sets of coils, and multiple sets of tooth-like structures are opened on the stator housing and the mover core on both sides of each set of coils. A conductive copper ring is set on the inner wall of the stator housing on the side where one set of coils is located.

[0011] Linear bearings fitted at both ends of the moving part's inner core;

[0012] Support springs are provided at both ends inside the stator housing, with one end of the support spring fixed to the end cover and the other end facing the shoulder of the mover inner core;

[0013] The end of the moving core on the side where the conductive copper ring is located passes through the end cap on the same side and is connected to the spherical bearing, while the end cap on the other side is connected to the spherical bearing.

[0014] Furthermore, each end cap consists of a cap and two concentric rings, with the two concentric rings positioned on one side of the cap. A linear bearing is installed within the inner concentric ring, and a support spring is fitted between the inner and outer concentric rings.

[0015] Furthermore, the outer wall of the outer concentric ring and the inner wall of the stator housing end are fixedly connected by threads.

[0016] Furthermore, a connecting hole is made in the center of the cap. One side of the connecting hole is used to install the spherical bearing, and the other side of the connecting hole is used to allow the end of the mover core to pass through.

[0017] Furthermore, the tooth-like structures on both the left and right sides of each coil are identical.

[0018] Furthermore, the depth of tooth b on the side where the conductive copper ring is located is less than the depth of tooth a on the other side.

[0019] Furthermore, both the stator shell and the mover core are made of ferromagnetic materials.

[0020] Furthermore, the support spring is a rectangular helical spring.

[0021] Furthermore, the inner core of the mover is a hollow structure with through holes along the axial direction inside.

[0022] Furthermore, an air gap is left between the stator shell and the mover core.

[0023] The beneficial effects of this invention are:

[0024] 1. To address the issues of slow adjustment speed and limited adjustment range in traditional shock absorbers, this invention introduces a cogging electromagnet, using electromagnetic restoring force to replace the elastic force of a mechanical spring. Based on the laws of electromagnetic induction and Lenz's law, this patent designs an electromagnetic spring and an electromagnetic damping unit, and introduces two sets of electromagnetic coils to control the magnetic field strength of the electromagnetic spring and the electromagnetic damper respectively, thereby achieving independent tuning of the shock absorber's stiffness and damping. It offers advantages such as fast stiffness and damping adjustment speed, high precision, and a wide adjustment range.

[0025] 2. This invention addresses the problems of traditional shock absorbers in automotive suspensions by designing a self-tuning electromagnetic suspension based on electromagnetic principles. This suspension can actively adjust its stiffness and damping to achieve optimal vibration isolation and adapt to changes in road conditions and driving modes.

[0026] 3. This system has a compact structure, light weight, a large range of adjustable stiffness coefficient and damping ratio, and also has the advantages of low noise, convenient maintenance, long system life, simple working principle, convenient control, and high reliability. Attached Figure Description

[0027] Figure 1 This is a structural diagram of a variable stiffness damping self-tuning electromagnetic suspension for automobiles.

[0028] Figure 2 This is a cross-sectional view of a variable stiffness damped self-tuning electromagnetic suspension for automobiles.

[0029] Figure 3 yes Figure 2 Enlarged view of a portion of the image;

[0030] Among them, 1. left end cover, 2. right end cover, 3. left joint bearing, 4. right joint bearing, 5. mover inner core, 6. stator housing, 7. conductive copper ring, 8. left coil, 9. right coil, 10. opening cover, 11. support spring, 12. linear bearing. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0032] like Figure 1 , 2 As shown, this invention is a variable stiffness and damping self-tuning electromagnetic suspension for automobiles, comprising: a left end cover 1, a right end cover 2, a left joint bearing 3, a right joint bearing 4, a mover inner core 5, a stator housing 6, a conductive copper ring 7, a left coil 8, a right coil 9, a support spring 11, and a linear bearing 12. The structure of each part and their interconnections are as follows:

[0033] More specifically, the left end cover 1 and the right end cover 2 are fixedly connected to both ends of the stator housing 6, respectively, to seal the interior of the stator housing 6 and form a sealed environment. Both the left end cover 1 and the right end cover 2 consist of a cap 10 and two concentric rings, with the two concentric rings positioned on one side of the cap 10. A linear bearing 12 is installed inside the inner concentric ring, and a support spring 11 is fitted between the inner and outer concentric rings; the outer wall of the outer concentric ring and the inner wall of the stator housing 6 end are fixedly connected by threads. A connecting hole is formed at the center of the cap 10.

[0034] More specifically, the stator housing 6 has a cylindrical structure, and the internal cavity is used to install the mover core 5. Its two ends are connected to the left end cover 1 and the right end cover 2, respectively.

[0035] More specifically, the mover inner core 5 is located inside the stator housing 6, and the mover inner core 5 can move axially within the stator housing 6. The two ends of the mover inner core 5 have smaller diameters and are respectively inserted into the linear bearings 12 at both ends.

[0036] Two coils are fitted in the middle section of the moving core 5: a left coil 8 and a right coil 9. Each coil has toothed structures on both sides of the stator shell 6 and the moving core 5, and these toothed structures are identical on both sides of each coil. The depth of the teeth b on both sides of the right coil 9 is less than the depth of the teeth a on both sides of the left coil 8; therefore, visually, the teeth of the right coil 9 are significantly smaller than those of the left coil 8.

[0037] In the initial state, the toothed structures on the stator shell 6 and the mover core 5 are opposite each other. When vibration causes the mover core 5 to move, the toothed structures will misalign, causing magnetic field line distortion and generating electromagnetic restoring force.

[0038] More specifically, a conductive copper ring 7 is provided on the inner wall of the stator housing 6 on the side where the right coil 9 is located. Functionally, the end where the right coil 9 is located is the electromagnetic damping part, and the other end where the left coil 8 is located is the electromagnetic spring part.

[0039] More specifically, the stator housing 6 and the mover core 5 are made of ferromagnetic materials, and the magnetic lines of force must pass through the conductors perpendicularly.

[0040] More specifically, in this application, the left end cap 1, located in the electromagnetic damping section, is directly threaded to the left spherical bearing 3 via a connecting hole, thus the end of the moving core 5 on this side can only move axially within the linear bearing 12. The end of the moving core 5, located in the electromagnetic spring section, protrudes from the connecting hole of the right end cap 2 and is threaded to the right spherical bearing 4. Therefore, the left spherical bearing 3 can be considered as the fixed end of the suspension, and the right spherical bearing 4 as the movable end.

[0041] More specifically, the inner core 5 of the moving part is thinner at both ends and thicker in the middle, thus forming a shoulder position; during the axial movement of the inner core 5 of the moving part, the shoulders on both sides can contact the support spring 11 on the same side respectively.

[0042] More specifically, the left joint bearing 3 has a size of 10mm, and the right joint bearing 4 has a size of 12mm.

[0043] The working principle of this device is as follows:

[0044] When the vehicle vibrates during operation, the moving core 5 of the connected self-tuning electromagnetic suspension moves back and forth or left and right. In the electromagnetic spring section, the toothed structure of the moving core 5 and the stator housing 6 misaligns, causing magnetic field distortion and generating an electromagnetic restoring force. The magnitude of this restoring force is proportional to the offset x, and the ratio is the equivalent spring constant of the electromagnetic spring. By changing the current in the electromagnetic spring coil, the equivalent spring constant can be steplessly adjusted. In the electromagnetic damping section, the excitation coil provides the main magnetic field. Because the moving core 5 has a certain speed during movement, it quickly cuts the conductor's magnetic field lines. Therefore, the relative motion between the conductor and the main magnetic field induces eddy currents in the conductor. The eddy currents interact with the excitation main magnetic field, generating an electromagnetic resistance force. The magnitude of this restoring force is proportional to the offset velocity v, and the ratio is the equivalent damping coefficient of the electromagnetic damping.

[0045] The inner core 5 of the moving element runs through the entire electromagnetic spring damper. Therefore, during the entire process of being subjected to micro-vibrations, three parameters—displacement x, velocity v, and acceleration a—will constantly change. According to Hooke's theorem, Newton's second law, and the calculated proportional relationship, the force at the right joint bearing 4 is the sum of these three parts. By adjusting the coil current of the electromagnetic spring and the electromagnetic damper, the resultant force of these three parts can be made zero, thus achieving the ideal vibration reduction effect.

[0046] To verify the effectiveness of this device, a simulation analysis of the design in this embodiment is performed as follows:

[0047] The cover 10 is made of electrical pure iron (industrial pure iron); the support spring 11 is a rectangular helical spring - high compression type standard part, its model is NT-SWR37-40_1, and the elastic coefficient is 29410N / m; the linear bearing 12 is a linear bearing - single-shield type standard part, its model is SLMUS10L.

[0048] Both the left spherical plain bearing 3 and the right spherical plain bearing 4 are standard parts. The left spherical plain bearing 3 is an economical self-lubricating spherical plain bearing with internal thread, and its model number is E-GZN10. The right spherical plain bearing 4 is also an economical self-lubricating spherical plain bearing with internal thread, and its model number is E-GZW12_203.

[0049] The mover inner core 5 and the stator outer shell 6 are both made of electrical pure iron (industrial pure iron). Based on engineering experience, the basic parameters are as follows: mover inner diameter 20mm, tooth pitch t=10mm, mover working surface diameter 120mm, tooth width b=2mm, mover length 96mm, tooth height g=3mm; stator sleeve inner diameter 132.5mm, tooth groove width 8mm, stator sleeve outer diameter 152.5mm, air gap 0.25mm, stator sleeve length 96mm.

[0050] The conductive copper ring 7, the left coil 8, and the right coil 9 are all made of brass. Based on engineering experience, the dimensions of the left coil 8 and the right coil 9 are 32mm × 20mm.

[0051] The magnetic circuit of the electromagnetic spring was calculated using the 2D Magnetostatic Field Solver in the electromagnetic finite element analysis software Maxwell Ansoft.

[0052] Simulation results show that the electromagnetic force reaches its maximum value when the axial displacement of the inner core 5 of the mover is around 2.5 mm. When the current is 10 A, Fmax = 10,437 N. It can be calculated that Kmax = Fmax * 1000 / 2.5 = 4,174,896 / m.

[0053] When no current is applied, the stiffness of the vibration damping platform is entirely provided by the mechanical spring, i.e., 29410 N / m. Therefore, the elastic coefficient adjustment range of the present invention can reach more than 140 times.

[0054] The above embodiments are only used to illustrate the design concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made based on the principles and design ideas disclosed in the present invention are within the protection scope of the present invention.

Claims

1. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles, characterized in that, include: Stator housing (6) End caps fixedly connected to both ends of the stator housing (6); The mover core (5) is movably installed inside the stator housing (6). Two sets of coils are installed on the mover core (5), and multiple sets of tooth-like structures are opened on the stator housing (6) and the mover core (5) on both sides of each set of coils. A conductive copper ring (7) is set on the inner wall of the stator housing (6) on the side where one set of coils is located. Two sets of electromagnetic coils are introduced to control the electromagnetic spring stiffness and electromagnetic damping respectively. Linear bearings (12) are fitted at both ends of the inner core (5) of the moving part; Support springs (11) are provided at both ends inside the stator housing (6). One end of the support spring (11) is fixed to the end cover, and the other end faces the shoulder of the moving core (5). The end of the moving core (5) on the side where the conductive copper ring (7) is located passes through the end cap on the same side and is connected to the spherical bearing; the end cap on the other side is connected to the spherical bearing. The depth of tooth b on the side where the conductive copper ring (7) is located is less than the depth of tooth a on the other side. In the initial state, the tooth-like structures on the stator shell (6) and the mover core (5) are opposite each other. When vibration causes the mover core (5) to move, the tooth-like structures will be misaligned, causing magnetic field line distortion and generating electromagnetic restoring force.

2. The variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, The end caps are all composed of a cap (10) and two concentric rings. The two concentric rings are set on one side surface of the cap (10). A linear bearing (12) is installed in the inner concentric ring, and a support spring (11) is installed between the inner and outer concentric rings.

3. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 2, characterized in that, The outer wall of the outer concentric ring and the inner wall of the stator housing (6) are fixedly connected by threads.

4. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 2, characterized in that, A connection hole is made in the center of the cap (10). One side connection hole is used to install the spherical bearing, and the other side connection hole is used to allow the end of the mover inner core (5) to pass through.

5. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, The tooth-like structures on both sides of each coil are identical.

6. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, The stator shell (6) and the mover core (5) are both made of ferromagnetic materials.

7. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, The support spring (11) is a rectangular helical spring.

8. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, The inner core (5) of the mover is a hollow structure with through holes along the axial direction inside.

9. A variable stiffness and damping self-tuning electromagnetic suspension for automobiles according to claim 1, characterized in that, An air gap is left between the stator shell (6) and the mover core (5).

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