Electromagnetic energy feedback type double-cylinder magnetorheological damper and automobile suspension damping system

Abstract

The invention discloses an electromagnetic energy feedback type double-cylinder magnetorheological damper and an automobile suspension damping system. The shock absorber comprises a liquid storage barrel and a working barrel. A damping piston is arranged in the working barrel in a sliding manner; the damping piston is fixedly connected with the bottom end of the piston rod; a magnet exciting coil is embedded in the peripheral face of the damping piston. A dustproof shell is arranged outside the liquid storage cylinder in a sleeving manner; the dustproof shell is in sliding connection with the liquid storage cylinder; the piston rod is fixedly connected with the dustproof shell; a permanent magnet is arranged on the outer wall of the liquid storage cylinder; the inner wall of the dustproof shell is provided with a group of energy feedback coils which are distributed at intervals along the axial direction, and the energy feedback coils are connected in parallel; when the shock absorber works, the magnetorheological fluid in the liquid storage cylinder generates a magnetorheological effect under the action of a magnetic field of the permanent magnet so as to generate additional damping force, and meanwhile, the dustproof shell can move relative to the liquid storage cylinder under the driving of the piston rod, so that the energy feedback coil cuts magnetic induction lines generated by the permanent magnet, mechanical energy is converted into electric energy, and energy recovery is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of shock absorbers, and particularly to an electromagnetic energy-fed double-tube magnetorheological shock absorber and an automotive suspension shock absorption system. Background Art

[0002] Magnetorheological fluid is a kind of intelligent material that can rapidly and reversibly transform from Newtonian fluid to non-Newtonian fluid under the magnetic effect. It is mainly composed of tiny soft magnetic particles with high magnetic permeability and low hysteresis and a non-magnetic conductive liquid. The magnetorheological shock absorber is made by using the magnetorheological characteristics of the magnetorheological fluid. In the early stage, due to problems such as poor material stability and complex magnetic circuit design of the device, the development of the magnetorheological shock absorber was relatively slow; however, since the 1990s, with the continuous development of preparation technology, the performance of the magnetorheological fluid has been continuously improved, and the research and development of the magnetorheological shock absorber have become a hot topic for scholars.

[0003] The magnetorheological shock absorber provides a magnetic field by setting an excitation coil on the piston; during operation, with the change of external vibration, the magnetic field strength can be changed by changing the magnitude of the current in the coil, thereby changing the rheological characteristics of the magnetorheological fluid, and further obtaining continuously adjustable damping force to achieve shock absorption of the vehicle body. Due to the advantages of good controllability of damping force, strong adaptability to high temperature, fast response speed, etc., the magnetorheological shock absorber has been widely used in the vehicle semi-active suspension system at present. However, the existing magnetorheological shock absorber relies on the excitation coil to provide damping force. When the excitation coil is damaged, the damping force will disappear, resulting in the failure of the shock absorber and affecting vehicle shock absorption; in addition, the shock absorber needs an external power supply during use, and it cannot recover the vibration energy of the suspension by itself, thus restricting the further popularization and application of the magnetorheological shock absorber. Summary of the Invention

[0004] The present application provides an electromagnetic energy-fed double-cylinder magnetorheological shock absorber to overcome the above problems existing in the prior art. In the electromagnetic energy-fed double-cylinder magnetorheological shock absorber of the present application, a permanent magnet is provided on the outer wall of the liquid storage cylinder. When the shock absorber works, the magnetorheological fluid in the working cylinder will be affected by the magnetic field of the excitation coil to generate a damping force. At the same time, the magnetorheological fluid in the liquid storage cylinder will be affected by the magnetic field of the permanent magnet to generate an additional damping force, thereby improving the damping force output of the magnetorheological shock absorber and increasing the bearable strength of the magnetorheological shock absorber. Moreover, when the excitation coil is damaged, a certain magnetic field can also be provided by the permanent magnet to prevent the shock absorber from failing. In addition, a dust-proof housing is provided outside the liquid storage cylinder, and an energy-fed coil is provided on the inner wall of the dust-proof housing. During use, the dust-proof housing can be driven by the piston rod to move relative to the liquid storage cylinder, so that the energy-fed coil cuts the magnetic induction lines generated by the permanent magnet, and the mechanical energy is converted into electrical energy by electromagnetic induction to achieve energy recovery, improving the energy utilization rate. Correspondingly, the present application also provides an automotive suspension shock absorber system equipped with the above electromagnetic energy-fed double-cylinder magnetorheological shock absorber.

[0005] For the shock absorber, the technical solution of the present application is as follows:

[0006] An electromagnetic energy-fed double-cylinder magnetorheological shock absorber, comprising a liquid storage cylinder; a working cylinder is arranged in the liquid storage cylinder; the working cylinder is connected to the liquid storage cylinder through a bottom valve at the bottom; a damping piston is slidably arranged in the working cylinder; the damping piston is fixedly connected to the bottom end of the piston rod; an excitation coil is embedded on the outer peripheral surface of the damping piston; a dust-proof housing is sleeved outside the liquid storage cylinder; the dust-proof housing is slidably connected to the liquid storage cylinder; the piston rod is fixedly connected to the dust-proof housing; a permanent magnet is provided on the outer wall of the liquid storage cylinder; a group of energy-fed coils are arranged on the inner wall of the dust-proof housing at intervals along the axis, and the energy-fed coils are connected in parallel with each other; when the shock absorber works, the magnetorheological fluid in the liquid storage cylinder is affected by the magnetic field of the permanent magnet to generate a magnetorheological effect and then generate an additional damping force. At the same time, the dust-proof housing will move relative to the liquid storage cylinder under the drive of the piston rod, so that the energy-fed coil cuts the magnetic induction lines generated by the permanent magnet, and the mechanical energy is converted into electrical energy by electromagnetic induction to achieve energy recovery.

[0007] Compared with the prior art, the electromagnetic energy-fed double-cylinder magnetorheological damper of the present application can realize the recovery and utilization of energy while improving the damping force through a clever structural design; it includes a working cylinder, a liquid storage cylinder and a dust-proof outer shell sleeved in sequence; wherein, a permanent magnet is arranged on the outer wall of the liquid storage cylinder, and an energy-fed coil is arranged on the inner wall of the dust-proof outer shell; when the damper works, the magnetorheological fluid will flow back and forth between the working cylinder and the liquid storage cylinder through the bottom valve. When the excitation coil is energized, the magnetorheological fluid in the working cylinder will be affected by the magnetic field generated by the excitation coil and change its rheological properties, changing from a Newtonian fluid without a magnetic field to a Bingham fluid under the action of a strong magnetic field, and undergoing shear flow under the extrusion of the damping piston to generate a damping force; at the same time, the magnetorheological fluid in the liquid storage cylinder will be affected by the magnetic field of the permanent magnet outside the liquid storage cylinder and change into a Bingham fluid, generating an additional damping force during the flow process; thus, when the damper works, a damping force will be generated in each of the working cylinder and the liquid storage cylinder, thereby increasing the damping force output of the magnetorheological damper and increasing the bearing strength of the magnetorheological damper; moreover, when the excitation coil is damaged or the like, a certain magnetic field can also be provided by the permanent magnet to generate a damping force, avoiding the failure of the damper; in addition, the dust-proof outer shell can be driven by the piston rod to move relative to the liquid storage cylinder, so that the energy-fed coil cuts the magnetic induction lines generated by the permanent magnet, and the mechanical energy is converted into electrical energy by electromagnetic induction, thereby realizing the recovery and utilization of energy and improving the energy utilization rate.

[0008] As an optimization, in the aforementioned electromagnetic energy-fed double-cylinder magnetorheological damper, the permanent magnet includes a group of A annular permanent magnets and a group of B annular permanent magnets; the A annular permanent magnets and the B annular permanent magnets are arranged at intervals alternately, and the magnetic pole directions are opposite. Thus, the magnetic field range perpendicular to the axial direction of the liquid storage cylinder is greatly increased compared with that of a single permanent magnet, thereby increasing the effective damping length. And because the magnetic pole directions of the A annular magnet and the B annular magnet are opposite, the magnetic fields generated by the two are superimposed, and the magnetic flux of the magnetic field perpendicular to the axial direction of the liquid storage cylinder is stronger, so that the damping force generated by the action of the magnetic field of the permanent magnet on the magnetorheological fluid in the liquid storage cylinder is significantly increased, thereby greatly increasing the maximum damping force of the magnetorheological damper and increasing the damping force output range of the magnetorheological damper. In addition, when the permanent magnet is arranged in the above manner, due to the large and strong magnetic field distribution range perpendicular to the axial direction of the liquid storage cylinder, the electric energy generated by the energy-fed coil cutting the magnetic induction lines during operation is also greatly increased, and the energy recovery ability is significantly improved. Further, limiting rings are respectively arranged at both ends of the permanent magnet, and adjacent A annular permanent magnets and B annular permanent magnets are separated by a separation ring; the separation ring is non-magnetic. Thus, the overall structural stability of the permanent magnet is good. Further, the limiting ring is welded and fixed to the liquid storage cylinder. At this time, the processing is convenient and easy to implement. Further, the thickness of the separation ring is 0.5 - 2 cm. Thus, a reasonable distance is provided between adjacent A annular permanent magnets and B annular permanent magnets, and the use effect is good.

[0009] As an optimization, in the aforementioned electromagnetic energy-feeding double-tube magnetorheological shock absorber, the permanent magnet can be made of neodymium iron boron magnet material, which has extremely high magnetic energy product and coercive force, and good stability, so that the prepared permanent magnet has higher magnetic properties. Further, the liquid storage cylinder is preferably made of non-magnetic stainless steel. As a result, the liquid storage cylinder will not change the magnetic field distribution and intensity of the permanent magnet due to magnetization, and the strength of the liquid storage cylinder is good. Further, the working cylinder can be made of non-magnetic aluminum alloy. Non-magnetic aluminum alloy can prevent the magnetic fields of the permanent magnet and the excitation coil from interfering with each other, and has the advantage of lightweight.

[0010] For the vibration reduction system, the technical solution of this application is:

[0011] The automobile suspension vibration reduction system comprises a shock absorber, a power module, a control module, and a height sensor matched with the automobile; the shock absorber is the aforementioned electromagnetic energy feeding type double-tube magnetorheological shock absorber of the present application; the power module comprises a power supply unit and a power storage unit, the power storage unit is electrically connected to the energy feeding coil in the shock absorber, and the power supply unit is electrically connected to the excitation coil in the shock absorber; when working, the height sensor detects the state of the tire, and when the tire bounce is detected, the signal is transmitted to the control module, the control module controls the power supply unit to energize the excitation coil, so that the excitation coil generates a magnetic field, and the magnetorheological fluid changes its rheological properties under the action of the magnetic field of the excitation coil, generates a damping force, and prevents the piston rod from moving upward or downward; in this process, the dustproof shell in the shock absorber will move relative to the liquid storage cylinder driven by the piston rod, so that the energy feeding coil cuts the magnetic flux lines generated by the permanent magnet, and uses electromagnetic induction to convert mechanical energy into electrical energy, and inputs it into the power storage unit.

[0012] Compared with the prior art, the automobile suspension vibration reduction system of the present application is equipped with a shock absorber of a specific structure. When the shock absorber is working, it can generate a damping force in the working cylinder and the liquid storage cylinder respectively, thereby improving the damping force output and enhancing the vibration reduction performance of the system; and during the operation of the shock absorber, it can also realize energy recovery and utilization through the mutual cooperation of its internal permanent magnet and energy feeding coil, thereby improving energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the structure of the electromagnetic energy-feeding double-tube magnetorheological shock absorber in the embodiment of the present application;

[0014] Figure 2 yes Figure 1 Schematic diagram of the structure of the magnetorheological damper after removing the dustproof shell.

[0015] The reference signs in the drawings are as follows: 1 - liquid storage cylinder; 2 - working cylinder; 3 - dust-proof housing; 4 - energy feeding coil; 5 - permanent magnet, 51 - A-ring permanent magnet, 52 - B-ring permanent magnet; 6 - piston rod; 7 - damping piston; 8 - exciting coil; 9 - bottom valve; 10 - limit ring; 11 - magnetic isolation ring; 12 - oil seal guide; 13 - bottom cover; 14 - lifting ring. Detailed implementation manners

[0016] The present application will be further described below in conjunction with the drawings and embodiments, but it shall not be used as a basis for limiting the present application. The content not described in detail in the following embodiments is all common technical knowledge in the art.

[0017] Embodiment:

[0018] See Figure 1 , the electromagnetic energy-feeding type double-cylinder magnetorheological damper of the present application includes a liquid storage cylinder 1; a working cylinder 2 is arranged in the liquid storage cylinder 1; the working cylinder 2 is communicated with the liquid storage cylinder 1 through a bottom valve 9 at the bottom; an oil seal guide 12 is arranged at the upper end of the liquid storage cylinder 1, and the lower end is sealed by a bottom cover 13; the top end of the working cylinder 2 is fixed on the oil seal guide 12; a damping piston 7 is slidably arranged in the working cylinder 2; the damping piston 7 is fixedly connected to the bottom end of a piston rod 6; an exciting coil 8 is embedded on the outer peripheral surface of the damping piston 7; the piston rod 6 is hollow, and the lead of the exciting coil 8 is led out from the hollow structure of the piston rod 6; a gap is left between the damping piston 7 and the inner wall of the working cylinder 2 to form a damping gap; a dust-proof housing 3 is sleeved outside the liquid storage cylinder 1; the dust-proof housing 3 is slidably connected with the liquid storage cylinder 1; the piston rod 6 is fixedly connected with the dust-proof housing 3; a permanent magnet 5 is arranged on the outer wall of the liquid storage cylinder 1; a group of energy feeding coils 4 are arranged on the inner wall of the dust-proof housing 3 at intervals along the axial direction, and the energy feeding coils 4 are connected in parallel with each other.

[0019] When the magneto-rheological shock absorber works, the excitation coil 8 is energized, and the piston rod 6 reciprocates in the working cylinder 2, causing the magneto-rheological fluid to flow back and forth between the working cylinder 2 and the reservoir cylinder 1 through the bottom valve 9; at this time, the magneto-rheological fluid in the working cylinder 2 is affected by the magnetic field generated by the excitation coil 8, and the magneto-rheological fluid in the reservoir cylinder 1 is affected by the magnetic field generated by the permanent magnet 5, changing from a Newtonian fluid without a magnetic field to a Bingham fluid under the action of a strong magnetic field. The suspended particles in the magneto-rheological fluid change from magnetic neutrality to strong magnetism, interact with each other, and transform into a macroscopic columnar structure, making it instantaneously change from a liquid to a viscoplastic body, and then the rheological properties change, showing mechanical properties similar to those of a solid, thereby generating a damping force in the reservoir cylinder 1 and the working cylinder 2 respectively; at the same time, the dust-proof housing 3 moves relative to the reservoir cylinder 1 driven by the piston rod 6, causing the energy harvesting coil 4 to cut the magnetic induction lines generated by the permanent magnet 5, and converting mechanical energy into electrical energy by electromagnetic induction (that is, converting the vibration energy transmitted from the road surface to the shock absorber into electrical energy), realizing the recovery and utilization of energy.

[0020] See Figure 2 , in this embodiment, the permanent magnet 5 includes a group of A annular permanent magnets 51 and a group of B annular permanent magnets 52; the A annular permanent magnets 51 and the B annular permanent magnets 52 are arranged at intervals and alternately, and the magnetic pole directions are opposite. Thus, the magnetic field range perpendicular to the axial direction of the reservoir cylinder 1 is greatly increased compared with that of a single permanent magnet, thereby increasing the effective damping length. And because the magnetic pole distribution directions of the A annular magnet 51 and the B annular magnet 52 are opposite, the magnetic fields generated by the two are superimposed, and the magnetic flux of the magnetic field perpendicular to the axial direction of the reservoir cylinder 1 is stronger, so that the damping force generated by the action of the magnetic field of the permanent magnet 5 on the magneto-rheological fluid in the reservoir cylinder 1 is significantly increased, thereby greatly improving the maximum damping force of the magneto-rheological shock absorber and increasing the damping force output range of the magneto-rheological shock absorber. In addition, when the permanent magnet 5 is arranged in the above manner, due to the large and strong magnetic field distribution range perpendicular to the axial direction of the reservoir cylinder 1, the electrical energy generated by the energy harvesting coil 4 cutting the magnetic induction lines during operation is also greatly increased, and the energy recovery ability is significantly improved.

[0021] In this embodiment, limiting rings 10 are respectively arranged at both ends of the permanent magnet 5, and the adjacent A annular permanent magnets 51 and B annular permanent magnets 52 are separated by a spacer ring 11; the spacer ring 11 is non-magnetic. Thus, the overall structural stability of the permanent magnet 5 is good. Further, the limiting rings 10 are fixedly welded to the reservoir cylinder 1. At this time, the processing is convenient and easy to implement. Further, the thickness of the spacer ring 10 is 1 cm. Thus, a reasonable distance is provided between the adjacent A annular permanent magnets 51 and B annular permanent magnets 52, and the use effect is good. Further, the permanent magnet 5 has an axial magnetization structure and is easy to process.

[0022] In this embodiment, a lifting lug 14 is respectively provided on the top of the piston rod 6 and the bottom of the bottom cover 13. Thus, the shock absorber can be installed on the car through the lifting lug 14, and the installation is convenient and easy to implement.

[0023] In this embodiment, the permanent magnet 5 is made of neodymium iron boron magnet; the isolation ring 11 and the working cylinder 2 are made of non-magnetic aluminum alloy; and the liquid storage cylinder 1 is made of non-magnetic stainless steel.

[0024] As a specific application of the electromagnetic energy-feeding double-tube magnetorheological shock absorber of this application:

[0025] The automobile suspension vibration reduction system comprises a shock absorber, a power module, a control module, and a height sensor matched with the automobile; the shock absorber is the electromagnetic energy feeding type double-tube magnetorheological shock absorber in the aforementioned embodiment; the power module comprises a power supply unit and a power storage unit, the power storage unit is electrically connected to the energy feeding coil 4 in the shock absorber, and the power supply unit is electrically connected to the excitation coil 8 in the shock absorber; when working, the height sensor detects the state of the tire, and transmits the signal to the control module when the tire bounce is detected; the control module controls the power supply unit to energize the excitation coil 8, so that the excitation coil 8 generates a magnetic field, and the magnetorheological fluid changes its rheological properties under the action of the magnetic field of the excitation coil 8, generates a damping force, and prevents the piston rod 6 from moving upward or downward; in this process, the dustproof shell 3 in the shock absorber will move relative to the liquid storage cylinder 1 under the drive of the piston rod 6, so that the energy feeding coil 4 cuts the magnetic flux lines generated by the permanent magnet 5, and uses electromagnetic induction to convert mechanical energy into electrical energy and input it into the power storage unit.

[0026] In the above application, when the vibration reduction system is working, the height sensor detects the state of the tire, and when the tire bounce is detected, the signal is transmitted to the control module; when the detected bounce is less than the set value, the control module controls the power supply unit not to energize the excitation coil 8. At this time, the magnetorheological fluid in the working cylinder 2 will not be affected by the magnetic field, and no damping force will be generated, while the magnetorheological fluid in the liquid storage cylinder 1 will be affected by the magnetic field of the permanent magnet 5 and generate damping force, thereby preventing the piston rod 6 from moving upward or downward; when the detected bounce is greater than the set value, the control module controls the power supply unit to energize the excitation coil 8.

[0027] The above general description of the invention involved in this application and the description of its specific implementation methods should not be understood as limiting the technical solutions of the invention. Based on the disclosure of this application, those skilled in the art can, without violating the constituent elements of the invention involved, add, reduce or combine the disclosed technical features in the above general description or / and specific implementation methods (including examples) to form other technical solutions within the scope of protection of this application.

Claims

1. An electromagnetic energy-feeding double-tube magnetorheological shock absorber, comprising a liquid storage cylinder (1); a working cylinder (2) is arranged inside the liquid storage cylinder (1); the working cylinder (2) is connected to the liquid storage cylinder (1) through a bottom valve (9) at the bottom; a damping piston (7) is slidably arranged inside the working cylinder (2); the damping piston (7) is fixedly connected to the bottom end of a piston rod (6); an excitation coil (8) is embedded on the outer peripheral surface of the damping piston (7); the characteristics are: The outer sleeve of the liquid storage cylinder (1) is provided with a dustproof housing (3); the dustproof housing (3) is slidably connected to the liquid storage cylinder (1); the piston rod (6) is fixedly connected to the dustproof housing (3); a permanent magnet (5) is provided on the outer wall of the liquid storage cylinder (1); a group of energy feeding coils (4) are arranged at intervals along the axial direction on the inner wall of the dustproof housing (3), and the energy feeding coils (4) are connected in parallel with each other; when the shock absorber is working, the magnetorheological fluid in the liquid storage cylinder (1) is affected by the magnetic field of the permanent magnet (5) to generate a magnetorheological effect and thus generate additional damping force; at the same time, the dustproof housing (3) moves relative to the liquid storage cylinder (1) under the drive of the piston rod (6), so that the energy feeding coil (4) cuts the magnetic flux lines generated by the permanent magnet (5), and uses electromagnetic induction to convert mechanical energy into electrical energy, thereby realizing energy recovery.

2. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to claim 1 is characterized in that: The permanent magnets (5) comprise a group of A annular permanent magnets (51) and a group of B annular permanent magnets (52); the A annular permanent magnets (51) and the B annular permanent magnets (52) are alternately arranged at intervals and have opposite magnetic pole directions.

3. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to claim 2 is characterized in that: Limiting rings (10) are respectively provided at both ends of the permanent magnet (5), and adjacent A annular permanent magnets (51) and B annular permanent magnets (52) are separated by isolation rings (11), wherein the isolation rings (11) are non-magnetic.

4. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to claim 3 is characterized in that: The thickness of the isolation ring (11) is 0.5-2 cm.

5. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to claim 3 is characterized in that: The limiting ring (10) is fixed to the liquid storage cylinder (1) by welding.

6. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to any one of claims 1 to 5, characterized in that: The permanent magnet (5) is made of neodymium iron boron magnet material.

7. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to any one of claims 1 to 5, characterized in that: The liquid storage cylinder (1) is made of non-magnetic stainless steel.

8. The electromagnetic energy-feeding double-tube magnetorheological shock absorber according to any one of claims 1 to 5, characterized in that: The working cylinder (2) is made of non-magnetic aluminum alloy.

9. Automobile suspension vibration reduction system, characterized in that: The invention comprises a shock absorber, a power module, a control module, and a height sensor which is matched with the vehicle; the shock absorber is the electromagnetic energy-feeding double-tube magnetorheological shock absorber as claimed in claim 1; the power module comprises a power supply unit and a power storage unit, the power storage unit is electrically connected to the energy-feeding coil (4) in the shock absorber, and the power supply unit is electrically connected to the excitation coil (8) in the shock absorber; during operation, the height sensor detects the state of the tire, and transmits a signal to the control module when the tire bounce is detected; the control module controls the power supply unit to energize the excitation coil (8), so that the excitation coil (8) generates a magnetic field, and the magnetorheological fluid changes its rheological properties under the action of the magnetic field of the excitation coil (8), generates a damping force, and prevents the piston rod (6) from moving upward or downward; in this process, the dustproof housing (3) in the shock absorber moves relative to the liquid storage cylinder (1) under the drive of the piston rod (6), so that the energy-feeding coil (4) cuts the magnetic flux lines generated by the permanent magnet (5), and uses electromagnetic induction to convert mechanical energy into electrical energy, which is then input into the power storage unit.

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