An adaptive flow channel switching asymmetric characteristic magneto-rheological damper

Abstract

The application discloses an asymmetric characteristic magnetorheological damper with self-adaptive flow channel switching, and belongs to the technical field of automobile suspension systems, which comprises an asymmetric flow channel switching piston assembly, a damper cylinder assembly, a floating piston assembly and a guider assembly. The outer cylinder guide belt of the asymmetric flow channel switching piston assembly and the inner wall of the damper cylinder assembly are coaxially matched in a surface contact mode. The piston rod of the asymmetric flow channel switching piston assembly passes through the guider assembly on the top of the damper in a coaxial mode, and the floating piston assembly is coaxially arranged in the lower chamber below the asymmetric flow channel switching piston assembly. The asymmetric flow channel switching piston assembly comprises three annular damping flow channels, and different profiled flow changing valve plates are arranged at the head and tail of two annular damping flow channels. The application can improve the riding comfort and the control stability of the vehicle.

Description

Technical Field

[0001] This invention belongs to the technical field of automotive suspension systems, specifically relating to an asymmetric magnetorheological damper with adaptive flow channel switching. Background Technology

[0002] With the continuous upgrading of automotive suspension system technology, the dynamic performance requirements of vehicle dampers are becoming increasingly stringent, especially when balancing the contradictory performance indicators of ride comfort and handling stability. Traditional magnetorheological dampers face significant challenges in this regard. Magnetorheological dampers, with their advantages of rapid response, compact structure, and continuously adjustable damping force, have become one of the core components of automotive suspension systems. However, their inherent design flaws still limit their overall performance breakthrough. Specifically, the damping characteristics of traditional magnetorheological dampers are typically symmetrical, meaning that the damping force adjustment range is similar between the extension and compression strokes, making it difficult to meet the differentiated needs of vehicles under complex operating conditions. For example, a smaller damping force is needed during the compression stroke to absorb road impact energy and improve ride comfort; while a larger damping force is needed during the extension stroke to suppress changes in vehicle body posture and enhance handling stability. This lack of asymmetrical damping characteristics makes it difficult for existing dampers to achieve a dynamic balance between comfort and handling.

[0003] It is worth noting that although magnetorheological dampers have the ability to regulate damping force through a magnetic field, their regulation effect is still limited by the inherent framework of symmetrical flow channel design. Even if dynamic adjustment of damping force is achieved through current control, the damping characteristics of the extension and compression strokes will still be coupled due to the hysteresis of the controller in traditional symmetrical structures. For example, when the damping force is reduced in the compression stroke to absorb impact, the maximum damping force in the extension stroke will also be limited simultaneously, resulting in insufficient attitude stability for the vehicle during emergency lane changes or high-speed cornering; conversely, if the damping force in the extension stroke is increased by enhancing the magnetic field, the damping force in the compression stroke will also increase accordingly, exacerbating the transmission of road impacts to the vehicle body. This "symmetry constraint" brought about by the control system makes it difficult for existing technologies to break through the physical boundaries of asymmetric damping characteristics, resulting in the actual performance of the damper being unable to match the diverse dynamic requirements of the vehicle.

[0004] In existing technologies, the design of magnetorheological dampers primarily focuses on optimizing symmetrical damping characteristics. For example, increasing the number of magnetorheological fluid channels or adjusting the channel cross-sectional area can expand the damping force adjustment range. However, while such solutions reduce the basic damping force (zero-field damping force) during the compression stroke, they often simultaneously weaken the basic damping force during the extension stroke, leading to a decrease in handling stability adjustment capability. While using external electronically controlled valves or independent channel switching devices can achieve asymmetrical damping characteristics, their complex mechanical structures and high-precision control requirements significantly increase system costs and introduce additional failure risks, reducing the reliability and robustness of the suspension system. Furthermore, the magnetic field design of traditional magnetorheological dampers often struggles to cover the synchronous control of multiple channels, resulting in an imbalance in magnetic field utilization during the extension and compression strokes, further limiting the effectiveness of asymmetrical characteristics. Under high-speed impact conditions, the basic damping force during the compression stroke of existing magnetorheological dampers remains too high due to insufficient redundancy in the channel design, preventing effective attenuation of impact energy and directly affecting vehicle ride comfort.

[0005] Therefore, there is an urgent need for a magnetorheological damper capable of adaptively adjusting asymmetric damping characteristics. This damper should achieve dynamic matching between large damping forces during extension and small damping forces during compression through structural innovation, while simultaneously improving its bidirectional damping force adjustment range. This invention overcomes the limitations of traditional symmetric damping designs by employing an innovative asymmetric flow channel switching mechanism and multi-flow channel magnetic field collaborative control technology, providing a more efficient and reliable dynamic performance optimization solution for vehicle suspension systems. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: an adaptive flow channel switching asymmetric magnetorheological damper, comprising: an asymmetric flow channel switching piston assembly, a damper cylinder assembly, a floating piston assembly, and a guide assembly; the outer cylinder guide band of the asymmetric flow channel switching piston assembly and the inner wall of the damper cylinder assembly form a coaxial fit relationship through surface contact, thereby placing the asymmetric flow channel switching piston assembly in the internal chamber of the damper cylinder assembly and dividing the internal chamber of the damper cylinder assembly into upper and lower chambers; the asymmetric flow channel switching piston assembly... The piston rod of the component passes coaxially through the upper chamber and through the guide assembly at the top of the damper to achieve radial multi-degree-of-freedom constraint of the asymmetric flow channel switching piston assembly. The floating piston assembly is coaxially arranged in the lower chamber below the asymmetric flow channel switching piston assembly, dividing the lower chamber into two chambers. The asymmetric flow channel switching piston assembly includes three annular damping flow channels, and different flow-changing valve plates with different configurations are respectively set at the beginning and end of two of the annular damping flow channels, so that the adaptive flow channel switching asymmetric magnetorheological damper can adaptively change the combination mode of the flow channels according to the direction of motion.

[0007] The present invention has the following beneficial effects:

[0008] The asymmetric magnetorheological damper of this invention features an asymmetric flow channel switching piston assembly. This assembly adds two additional annular damping channels to the piston assembly of a traditional magnetorheological damper, and adds flow-modifying valves with different configurations at the beginning and end of each channel. This allows the damper to adaptively change the flow channel combination according to the direction of motion. During the compression stroke, the asymmetric magnetorheological damper of this invention adaptively achieves a three-channel parallel flow diversion and pressure relief effect through the flow-modifying valves, thereby significantly increasing the overall flow channel cross-sectional area during compression to reduce fluid pressure differential and thus significantly reducing the basic damping force of the asymmetric magnetorheological damper during compression. Furthermore, during the extension stroke, the flow-modifying valves adaptively achieve a three-channel series convergence effect, thereby significantly increasing the effective length of the flow channels without changing the overall flow channel cross-sectional area during extension, thus significantly increasing the basic damping force of the asymmetric magnetorheological damper during extension. This adaptive inherent asymmetric basic damping characteristic ensures that the suspension system is not affected by controller hysteresis. Furthermore, the excitation coils arranged between the two flow channels of this invention can achieve synchronous control of the entire flow channel, thereby enabling the asymmetric magnetorheological damper to have a wider damping force adjustment range in both compression and tension strokes. Combined with its asymmetric basic damping characteristics of large tension and small compression, it can achieve a comprehensive improvement in vehicle ride comfort and handling stability. Attached Figure Description

[0009] Figure 1This is an axial sectional view of the adaptive flow channel switching asymmetric magnetorheological damper of the present invention, wherein: 1-floating piston, 2-piston bottom end cap, 3-outer plug O-ring, 4-inner guide band of bottom diversion valve plate, 5-first positioning pin, 6-outer guide band of bottom diversion valve plate, 7-bottom helical spring, 8-second positioning pin, 9-outer lower magnetic guide plate, 10-inner coil frame, 11-outer coil frame, 12-transition lead, 13-inner plug O-ring, 14-inner plug, 15-outer guide band of top diversion valve plate, 16-top diversion valve plate, 17-top helical spring, 18-middle piston core, 19-top piston core, 20-stop ring gasket, 21-magnetorheological fluid, 22-outer cylinder of damper, 23-oil seal. 24-Spring, 25-Skeleton oil seal, 26-Guide O-ring, 27-Copper bushing, 28-Guide skeleton, 29-Glyd ring, 30-Buffer pad, 31-Outer lead wire, 32-Piston rod, 33-Stop ring, 34-Piston top end cap, 35-End cap retaining ring, 36-Piston outer cylinder, 37-Inner upper magnetic guide plate, 38-Outer upper magnetic guide plate, 39-Outer cylinder guide band, 40-Outer excitation coil, 41-Inner excitation coil, 42-Inner coil lead wire, 43-Inner lower magnetic guide plate, 44-Bottom diversion valve plate, 45-Outer coil lead wire, 46-Bottom piston core, 47-Outer plug, 48-Floating piston guide band, 49-Floating piston O-ring, 50-End cap, 51-Lifting lug;

[0010] Figure 2The figures show a bottom view and two cross-sectional views at different angles of the asymmetric flow channel switching piston assembly of the present invention, wherein: 2-piston bottom end cap; 201-selective inner flow channel groove; 202-normally open outer flow channel groove; 203-extension boss; 204-wire hole; 205-embedded wire groove; 3-outer plug O-ring; 4-inner guide band of bottom diversion valve plate; 5-first positioning pin; 6-outer guide band of bottom diversion valve plate; 7-bottom helical spring; 8-first positioning pin; 9-second positioning pin; 10-third positioning pin; 11-second positioning pin; 12-second positioning pin; 13-second positioning pin; 14-second positioning pin; 15-second positioning pin; 16-second positioning pin; 17-second positioning pin; 18-second positioning pin; 19-second positioning pin; 10-second positioning pin; 10-second positioning pin; 11-second positioning pin; 12 ... 9-Second locating pin, 10-External lower magnetic guide plate, 11-Internal coil frame, 12-External coil frame, 13-Transition lead wire, 14-Inner plug O-ring, 15-Inner plug, 16-Top diversion valve plate outer guide band, 17-Top diversion valve plate, 18-Top valve outer flow channel groove, 19-Top helical spring, 20-Middle piston core, 31-Top piston core, 22-Stop ring gasket, 33-Outer lead wire, 34-Piston rod, 35- - Stop ring, 33- Piston rod O-ring, 34- Piston top end cap, 3401- Radial inner flow channel groove, 3402- Axial outer flow channel groove, 35- End cap retaining ring, 36- Piston outer cylinder, 3601- Edge annular flow channel groove, 37- Inner upper magnetic guide plate, 3701- Inner through upper flow channel groove, 38- Outer upper magnetic guide plate, 3801- Radial flow channel groove, 40- External excitation coil, 41- Internal excitation coil, 42- Internal wire 43-Inner lower magnetic guide plate, 4301-Inner lower flow channel groove, 44-Bottom diversion valve plate, 4401-Bottom valve inner flow channel groove, 4402-Bottom valve outer flow channel groove, 45-Outer coil lead wire, 46-Bottom piston core, 47-Outer plug, 52-Outer coil insulation layer, 53-Inner coil insulation layer, 54-First damping flow channel, 55-Second damping flow channel, 56-Third damping flow channel, 57-Top inner flow channel groove;

[0011] Figure 3 This is a partial view of the components of the present invention; wherein, (a) is a top view of the piston outer cylinder, (b) is a top view of the piston top end cap, (c) is a bottom view of the top diversion valve plate, (d) is a top view of the bottom diversion valve plate, (e) is a top view of the inner lower magnetic guide plate, and (f) is a bottom view of the inner upper magnetic guide plate; wherein, 16-top diversion valve plate, 1601-top valve outer flow channel groove, 34-piston top end cap, 3402-axial outer flow channel groove, 36-piston outer cylinder, 3601-edge annular flow channel groove, 37-inner upper magnetic guide plate, 3701-inner upper flow channel groove, 43-inner lower magnetic guide plate, 4301-inner lower flow channel groove, 44-bottom diversion valve plate, 4401-bottom valve inner flow channel groove, and 4402-bottom valve outer flow channel groove;

[0012] Figure 4This is a cross-sectional view of the working state of the asymmetric flow channel switching piston assembly during the compression stroke of the present invention, wherein: 201-selective inner flow channel groove, 202-normally open outer flow channel groove, 7-bottom helical spring, 16-top diversion valve plate, 1601-top valve outer flow channel groove, 17-top helical spring, 34-piston top end cap, 3401-radial inner flow channel groove, 3402-axial outer flow channel groove, 40-external excitation coil, 41-internal excitation coil, 44-bottom diversion valve plate, 4401-bottom valve inner flow channel groove, 4402-bottom valve outer flow channel groove, 46-bottom piston core, 54-first damping flow channel, 55-second damping flow channel, 56-third damping flow channel, 57-top inner flow channel groove;

[0013] Figure 5 This is a cross-sectional view of the working state of the asymmetric flow channel switching piston assembly in the extension stroke of the present invention, wherein: 2-piston bottom end cap, 201-selective inner flow channel groove, 202-normally open outer flow channel groove, 7-bottom helical spring, 16-top diversion valve plate, 1601-top valve outer flow channel groove, 17-top helical spring, 3401-radial inner flow channel groove, 3402-axial outer flow channel groove, 38-outer upper magnetic guide plate, 3801-radial diversion groove, 40-outer excitation coil, 41-inner excitation coil, 44-bottom diversion valve plate, 54-first damping flow channel, 55-second damping flow channel, 56-third damping flow channel, 57-top inner flow channel groove. Detailed Implementation

[0014] 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 merely illustrative and not intended to limit the invention.

[0015] The adaptive flow channel switching asymmetric magnetorheological damper (or damper) of this invention includes an asymmetric flow channel switching piston assembly. This assembly adds two additional annular damping channels to the piston assembly of a traditional magnetorheological damper, and adds flow-modifying valves with different configurations at the beginning and end of each annular damping channel. This allows the damper to adaptively change the flow channel combination according to the direction of motion. During the compression stroke, the damper achieves a three-channel parallel flow diversion and pressure relief effect through the flow-modifying valves, thereby significantly increasing the overall flow channel cross-sectional area during the compression stroke to reduce the fluid pressure difference and thus significantly reducing the basic damping force of the damper during the compression stroke. Furthermore, during the extension stroke, the flow-modifying valves achieve a three-channel series convergence effect, thereby significantly increasing the effective length of the flow channels without changing the overall flow channel cross-sectional area during the extension stroke, and thus significantly improving the basic damping force of the damper during the extension stroke. Correspondingly, the excitation coils arranged between each pair of adjacent flow channels in this invention can achieve synchronous control of the entire flow channel, thereby enabling the asymmetric magnetorheological damper to have a wider damping force adjustment range in both compression and tension strokes. Combined with its asymmetric basic damping characteristics of large tension and small compression, it can achieve a comprehensive improvement in vehicle ride comfort and handling stability.

[0016] like Figure 1 , Figure 2 As shown, the adaptive flow channel switching asymmetric magnetorheological damper of the present invention includes: an asymmetric flow channel switching piston assembly, a damper cylinder assembly, a floating piston assembly, and a guide assembly. The outer cylinder guide band 39 of the asymmetric flow channel switching piston assembly forms a coaxial fit with the inner wall of the damper cylinder assembly through surface contact, thereby placing the asymmetric flow channel switching piston assembly in the internal chamber of the damper cylinder assembly and dividing the internal chamber of the damper cylinder assembly into upper and lower chambers. The piston rod of the asymmetric flow channel switching piston assembly coaxially passes through the upper chamber and through the guide assembly at the top of the damper to achieve radial multi-degree-of-freedom constraint of the asymmetric flow channel switching piston assembly. The floating piston assembly is coaxially disposed in the lower chamber below the asymmetric flow channel switching piston assembly, further dividing the lower chamber into two chambers, wherein the chamber below the floating piston assembly constitutes a volume compensation chamber.

[0017] The components of its assembly are as follows:

[0018] The damper cylinder assembly includes a lug 51, an end cap 50, and an outer cylinder 22. The lug 51 is welded to the lower end face of the end cap 50, and the end cap 50 is fixed to the bottom of the outer cylinder 22 using gas welding.

[0019] Floating piston assembly: includes floating piston 1, floating piston guide belt 48, and floating piston O-ring 49. The floating piston guide belt 48 and floating piston O-ring 49 are respectively installed in corresponding slots on the floating piston 1.

[0020] The guide assembly includes an oil seal snap ring 23, a skeleton oil seal 24, a guide O-ring 25, a copper bushing 26, a guide skeleton 27, a Glyd ring 28, and a buffer pad 29. The guide skeleton 27 is located at the top of the damper outer cylinder 22. The copper bushing 26 is installed in the slot between the skeleton oil seal 24 and the guide skeleton 27. The skeleton oil seal 24 is fixed to the stepped groove of the guide skeleton 27 by the oil seal snap ring 23. The guide O-ring 25 is installed in the sealing ring groove on the outer surface of the guide skeleton 27. The Glyd ring 28 is installed in the sealing ring groove on the inner surface of the guide skeleton 27 below the copper bushing 26. The buffer pad 29 is fixed to the bottom of the guide skeleton 27.

[0021] Asymmetric flow channel switching piston assembly: including piston bottom end cap 2, outer plug O-ring 3, bottom diversion valve inner guide band 4, first positioning pin 5, bottom diversion valve outer guide band 6, bottom helical spring 7, second positioning pin 8, outer lower magnetic guide plate 9, inner coil frame 10, outer coil frame 11, transition lead 12, inner plug O-ring 13, inner plug 14, top diversion valve outer guide band 15, top diversion valve 16, top helical spring 17, middle piston core 18, top piston core 19, stop 20. Moving ring pad, 30. External lead wire, 31. Piston rod, 32. Stop ring, 33. Piston rod O-ring, 34. Piston top end cap, 35. End cap retaining ring, 36. Piston outer cylinder, 37. Internal upper magnetic guide plate, 38. External upper magnetic guide plate, 39. External cylinder guide band, 40. External excitation coil, 41. Internal excitation coil, 42. Internal coil lead wire, 43. Internal lower magnetic guide plate, 44. Bottom diversion valve plate, 45. External coil lead wire, 46. Bottom piston core, 47. External plug, 52. External coil insulation layer, 53.

[0022] The following describes the composition, structure, and operation of the asymmetric flow channel switching piston assembly. Figure 2 , Figure 3As shown, the assembly relationship of the asymmetric flow channel switching piston assembly is as follows: Taking the piston bottom end cap 2 as the lowest part as the reference, the outer piston cylinder 36 is set on its outermost side, and the remaining parts are set inside the piston outer cylinder 36, which are divided into inner and outer rings. The inner ring parts are coaxially set at the center of the piston bottom end cap 2, and from bottom to top are the bottom piston core 46, the inner lower magnetic guide plate 43, the middle piston core 18, the inner upper magnetic guide plate 37, the top piston core 19, and the piston rod 31; among them, the outer plug 47 is set at the bottom of the bottom piston core 46, and the inner plug 14 is set at the bottom of the middle piston core 18; the inner coil frame 10, the inner excitation coil 41, and the inner coil insulation layer 53 are set between the inner upper magnetic guide plate 37 and the inner lower magnetic guide plate 43; the bottom diversion valve plate 44 is set between the piston bottom end cap 2 and the inner lower magnetic guide plate 43. The outer ring components are coaxially positioned at the edge of the piston bottom end cap 2, consisting of an outer lower magnetic guide plate 9 and an outer upper magnetic guide plate 38 from bottom to top. The outer coil frame 11, the outer excitation coil 40, and the outer coil insulation layer 52 are positioned between the outer lower magnetic guide plate 9 and the outer upper magnetic guide plate 38. The top diversion valve plate 16 is positioned between the outer upper magnetic guide plate 38 and the piston top end cap 34. The piston top end cap 34 is located on the top of the piston outer cylinder 36 and is used to lock all internal components.

[0023] The piston bottom end cap 2 is provided with two sets of circumferentially distributed axial annular flow channel grooves: a selective inner flow channel groove 201 and a normally open outer flow channel groove 202. Since the piston bottom end cap 2 is made of a diamagnetic material, the magnetic field's effect on the magnetorheological fluid 21 flowing through the two sets of annular flow channel grooves is not significant. Therefore, both the selective inner flow channel groove 201 and the normally open outer flow channel groove 202 require a large groove width to further reduce the basic damping force of the damper's bidirectional stroke. An extended boss 203 is provided on the lower end face of the piston bottom end cap 2, and a wrench groove is provided on the outer circular surface of the extended boss 203 to facilitate threaded assembly. The external lower magnetic guide plate 9 is installed in the annular positioning groove on the upper end face of the piston bottom end cap 2. The first positioning pin 5 is installed in the positioning pin hole on the lower end face of the external lower magnetic guide plate 9 and the upper end face of the annular positioning groove of the piston bottom end cap 2 to ensure that the external lower magnetic guide plate 9 and the piston bottom end cap 2 do not rotate relative to each other, thus preventing the external coil lead 45 from being cut off. A wire-passing hole 204 and a wire-buried groove 205 are provided opposite to the positioning pin hole on the lower end face of the piston bottom end cover 2. The wire-passing hole 204 penetrates the entire piston bottom end cover 2 and is used for the lead wire 45 of the external coil. The external coil frame 11 is set in a fixing groove on the circumferential inner surface of the coaxially mounted external lower magnetic guide plate 9 and external upper magnetic guide plate 38, close to the circumferential inner surface of the external lower magnetic guide plate 9 and external upper magnetic guide plate 38. The external upper magnetic guide plate 38 is positioned by a limiting boss on the inner surface of the piston outer cylinder 36, and the limiting boss on the inner surface of the piston outer cylinder 36 is provided with several circumferentially distributed edge annular flow channel grooves 3601, such as Figure 3As shown in (a); the outer surface of the outer coil frame 11, the upper end face of the outer lower magnetic plate 9, and the lower end face of the outer upper magnetic plate 38 together form the first winding groove, and the outer excitation coil 40 is wound in the first winding groove; the combination of the outer coil frame 11, the outer lower magnetic plate 9 and the outer upper magnetic plate 38, the outer excitation coil 40, and the outer coil insulation layer 52 disposed on the circumferential outer surface of the outer excitation coil 40 constitutes the external magnetic field generating assembly.

[0024] The bottom piston core 46 is mounted to the inner circular surface of the piston bottom end cap 2 via a positioning boss at its bottom end. The inner lower magnetic guide plate 43 is coaxially mounted to the positioning boss at the upper end of the bottom piston core 46. Then, the bottom piston core 46 and the inner lower magnetic guide plate 43 are mounted to the lower end face of the middle piston core 18 via threads at the upper end of the bottom piston core 46. The inner plug O-ring 13 is installed into the sealing ring groove on the outer surface of the inner plug 14. The inner plug 14 is located in the stepped groove at the bottom end of the middle piston core 18, and is mounted via... The upper end face of the bottom piston core 46 is locked; the inner lower magnetic guide plate 43 and the bottom piston core 46 are respectively provided with overlapping wire holes and lead holes for the lead wires 42 of the internal coil. At the same time, a second positioning pin 8 is provided in the corresponding pin hole between the middle piston core 18 and the inner lower magnetic guide plate 43 to ensure that the inner lower magnetic guide plate 43 and the middle piston core 18 will not rotate relative to each other, thereby preventing the lead wires 42 of the internal coil from being cut off; the inner upper magnetic guide plate 37 is coaxially mounted to the top piston core. The positioning boss at the lower end of the top piston core 19 is then used to install the top piston core 19 and the inner upper magnetic guide plate 37 to the upper end face of the middle piston core 18 via the thread at the lower end of the top piston core 19; the outer plug O-ring 3 is installed into the sealing ring groove on the outer surface of the outer plug 47, and the outer plug 47 is installed into the stepped groove at the bottom end of the bottom piston core 46; the inner coil frame 10 is located between the inner lower magnetic guide plate 43 and the inner upper magnetic guide plate 37, which are coaxially mounted, and close to the inner lower magnetic guide plate 43 and the inner upper magnetic guide plate 37. The inner circumferential surface of the magnetic plate 37 is fixed in a groove; the outer surface of the inner coil skeleton 10, the upper end face of the inner lower magnetic plate 43, and the lower end face of the inner upper magnetic plate 37 together form a second winding groove, and the inner excitation coil 41 is wound in the second winding groove; the combination of the inner coil skeleton 10, the inner lower magnetic plate 43, the inner upper magnetic plate 37, the inner excitation coil 41, and the inner coil insulation layer 53 disposed on the outer circumferential surface of the inner excitation coil 41 constitutes the inner magnetic field generating assembly.

[0025] Similarly, the stop ring 32 is disposed in a circular groove on the outer surface of the piston rod 31, and the stop ring pad 20 is disposed in a stepped groove inside the piston top end cap 34, contacting the stop ring 32 to achieve axial limiting of the piston rod 31. A piston rod O-ring 33 is disposed in a sealing ring groove on the lower end of the piston rod 31 and its circumferential outer surface to achieve sealing between the top piston core 19 and the piston rod 31. The piston top end cap 34 is provided with two sets of circumferentially distributed annular flow channel grooves: a radially inner flow channel groove 3401 and an axially outer flow channel groove 3402, as shown below. Figure 3 of (b) Figure 4 , Figure 5 As shown; both the radial inner flow channel groove 3401 and the axial outer flow channel groove 3402 require a large groove width to further reduce the basic damping force of the damper's bidirectional stroke; the piston bottom end cap 2 and piston top end cap 34 are respectively fixed to the bottom and top of the piston outer cylinder 36 by threads and end cap snap rings 35, thereby locking the internal parts.

[0026] like Figure 2 and Figure 3 As shown, the outer surface of the external magnetic field generating assembly and the inner surface of the piston outer cylinder 36 form a first damping flow channel 54; the inner surface of the external magnetic field generating assembly and the outer surface of the internal magnetic field generating assembly form a second damping flow channel 55. Figure 3 As shown in (e), in the internal magnetic field generating assembly, the internal lower magnetic guide plate 43 is provided with circumferentially distributed internal downward flow channel grooves 4301, such as... Figure 3 As shown in (f), the internal upper magnetic plate 37 is provided with an inner upper flow channel groove 3701 whose axial projection position coincides with that of the inner lower flow channel groove 4301. The inner lower flow channel groove 4301, the inner upper flow channel groove 3701, the outer surface of the central piston core 18, and the inner surface of the internal coil skeleton 10 together form the third damping flow channel 56. Figure 3 As shown in (d), the bottom diversion valve plate 44 is provided with two sets of circumferentially distributed axial annular flow channel grooves: the inner flow channel groove 4401 and the outer flow channel groove 4402 of the bottom valve. Each inner flow channel groove 4401, each outer flow channel groove 4402, and each normally open outer flow channel groove 202 have no overlapping area, ensuring that the bottom diversion valve plate 44 can completely close the selected inner flow channel groove 201 during the stretching stroke, thus achieving diversion. The inner guide band 4 and the outer guide band 6 of the bottom diversion valve plate are respectively disposed in the grooves on the inner and outer circumferential surfaces of the bottom diversion valve plate 44. The bottom diversion valve plate 44 is coaxially disposed between the outer guide surface (outer circumferential surface) of the bottom of the bottom piston core 46 and the inner guide surface (inner circumferential surface) of the bottom of the outer lower magnetic guide plate 9. One end of the bottom helical spring 7 is connected to the spring groove on the upper surface of the bottom diversion valve plate 44, and the other end is connected to the spring groove on the lower surface of the inner lower magnetic guide plate 43. The top diversion valve plate 16 is coaxially mounted on the inner surface above the limiting boss of the piston outer cylinder 36. Figure 3As shown in (c), the top diversion valve plate 16 is provided with a set of circumferentially distributed axial annular flow channel grooves: the top valve outer flow channel groove 1601, the axial projection position of the top valve outer flow channel groove 1601 coincides with the axial outer flow channel groove 3402, so as to ensure that the top valve outer flow channel groove 1601 will not block the axial outer flow channel groove 3402 during the compression stroke, thereby realizing flow diversion and pressure relief. At the same time, as Figure 2 , Figure 5 As shown, a radial flow-changing groove 3801 is provided at the top of the inner upper magnetic guide plate 37 to connect the first damping flow channel 54 and the second damping flow channel 55, so as to realize the flow channel series connection of the stretching stroke; the outer guide band 15 of the top flow-changing valve plate is provided in the groove on the circumferential outer surface of the top flow-changing valve plate 16, and the inner surface of the top flow-changing valve plate 16 and the outer surface of the top piston core 19 together form the top inner flow channel groove 57. One end of the top helical spring 17 is connected to the spring groove on the lower end face of the top flow-changing valve plate 16, and the other end is connected to the spring groove on the upper end face of the inner upper magnetic guide plate 37.

[0027] like Figure 2 As shown, the external excitation coil 40 passes through two external coil leads 45 via wire grooves on the external lower magnetic plate 9, through wire holes 204 in the piston bottom end cap 2 to the lower end face of the piston bottom end cap 2, then through the embedded wire groove 205 in the lower end face of the piston bottom end cap 2 to the metal connecting fork at the lower end of the outer plug 47, and finally through the transition lead 12 at the upper end of the outer plug 47 to the metal connecting fork at the lower end of the inner plug 14. The internal excitation coil 41 passes through two internal coil leads 42 via axial wire grooves on the internal lower magnetic plate 43, through radial wire holes on the internal lower magnetic plate 43, then through radial lead holes in the bottom piston core 46 to the metal connecting fork at the lower end of the inner plug 14, and finally through external leads 30 via the inner through holes of the middle piston core 18, the top piston core 19 and the piston rod 31 to the outside of the damper. The external excitation coil 40, external coil lead 45, internal excitation coil 41, and internal coil lead 42 are all covered with insulating material to prevent short circuits or breakage due to relative movement, thereby ensuring that the external magnetic field generating component and the internal magnetic field generating component can generate the excitation magnetic field normally.

[0028] like Figure 4As shown, when the asymmetric flow channel switching piston assembly is subjected to downward displacement excitation, the damper of the present invention enters the compression stroke. At this time, the pressure difference causes the bottom helical spring 7 to compress until the bottom diversion valve plate 44 contacts the bottom piston core 46, while the top helical spring 17 is stretched until the top diversion valve plate 16 contacts the piston top end cap 34. At this time, the magnetorheological fluid 21 enters the interior of the asymmetric flow channel switching piston assembly from the selected inner flow channel groove 201 and the normally open outer flow channel groove 202. The magnetorheological fluid 21 that has passed through the normally open outer flow channel groove 202 will further pass through the first damping flow channel 54; the magnetorheological fluid 21 that has passed through the selected inner flow channel groove 201 will be further diverted and enter the bottom valve inner flow channel groove 440 respectively. The magnetorheological fluid 21 entering the bottom valve inner flow channel 4401 and bottom valve outer flow channel 4402 will pass through the third damping flow channel 56 and the second damping flow channel 55 respectively. A portion of the magnetorheological fluid 21 passing through the second damping flow channel 55 will merge with the magnetorheological fluid 21 passing through the first damping flow channel 54 and enter the top valve outer flow channel 1601, and finally flow out of the asymmetric flow channel switching piston assembly through the axial outer flow channel 3402. The other portion of the magnetorheological fluid 21 passing through the second damping flow channel 55 will merge with the magnetorheological fluid 21 passing through the third damping flow channel 56 and enter the top inner flow channel 57, and finally flow out of the asymmetric flow channel switching piston assembly through the radial inner flow channel 3401. At this time, the first damping channel 54, the second damping channel 55, and the third damping channel 56 within the magnetic field excitation range are in a parallel depressurization state. Therefore, the flow velocity of the magnetorheological fluid 21 in the regions of the first damping channel 54, the second damping channel 55, and the third damping channel 56 during the compression stroke will decrease, thereby reducing the basic damping force of the compression stroke. On this basis, applying current excitation to the external excitation coil 40 and the internal excitation coil 41 simultaneously can ensure that the magnetorheological fluid 21 in the first damping channel 54, the second damping channel 55, and the third damping channel 56 are all covered by the radial magnetic field, increasing the magnetic field utilization rate and the adjustment range of the compression stroke of the asymmetric characteristic magnetorheological damper with adaptive channel switching.

[0029] like Figure 5As shown, when the asymmetric flow channel switching piston assembly is subjected to upward displacement excitation, the damper of the present invention enters the stretching stroke. At this time, the pressure difference will cause the bottom helical spring 7 to stretch to the point that the bottom diversion valve plate 44 contacts the piston bottom end cap 2, thereby blocking the selected inner flow channel groove 201. Meanwhile, the top helical spring 17 will compress to the point that the top diversion valve plate 16 contacts the outer upper magnetic guide plate 38, thereby blocking the top valve outer flow channel groove 1601. At this time, the magnetorheological fluid 21 enters the interior of the asymmetric flow channel switching piston assembly from the radial inner flow channel groove 3401 and the axial outer flow channel groove 3402 and flows together. After the flow is completed, the magnetorheological fluid 21 enters the third damping flow channel 56 through the top inner flow channel groove 57, then turns into the second damping flow channel 55, and then flows through the radial diversion groove 3801 to the first damping flow channel 54. Finally, it flows out of the asymmetric flow channel switching piston assembly through the normally open outer flow channel groove 202. At this time, the first damping channel 54, the second damping channel 55, and the third damping channel 56 within the magnetic field excitation range are connected in series to increase the effective length of the channels. Therefore, the flow velocity of the magnetorheological fluid 21 in the regions of the first damping channel 54, the second damping channel 55, and the third damping channel 56 during the stretching stroke will increase, thereby enhancing the basic damping force of the stretching stroke. On this basis, applying current excitation to the external excitation coil 40 and the internal excitation coil 41 simultaneously can ensure that the magnetorheological fluid 21 in the first damping channel 54, the second damping channel 55, and the third damping channel 56 are all covered by the radial magnetic field. In the series state, the effect of the magnetic field on the magnetorheological fluid 21 can be further superimposed. Therefore, the adjustment range of the stretching stroke of the asymmetric magnetorheological damper with adaptive channel switching will be further increased.

[0030] In combination with the above working states, the adaptive flow channel switching asymmetric magnetorheological damper of the present invention can adaptively adjust the working state of the internal flow channel according to the movement direction of the damper, thereby realizing asymmetric damping characteristics with large differences in basic damping force. At the same time, the dual excitation coils can also synchronously expand the damping force adjustment range during bidirectional movement.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An asymmetric magnetorheological damper with adaptive flow channel switching, characterized in that, include: The asymmetric flow channel switching piston assembly, damper cylinder assembly, floating piston assembly, and guide assembly are included. The outer cylinder guide band (39) of the asymmetric flow channel switching piston assembly and the inner wall of the damper cylinder assembly form a coaxial fit relationship through surface contact, thereby setting the asymmetric flow channel switching piston assembly in the chamber inside the damper cylinder assembly and dividing the inner chamber of the damper cylinder assembly into upper and lower chambers. The piston rod of the asymmetric flow channel switching piston assembly passes through the guide assembly at the top of the damper coaxially through the upper chamber to realize the radial multi-degree-of-freedom constraint of the asymmetric flow channel switching piston assembly. The floating piston assembly is coaxially set in the lower chamber below the asymmetric flow channel switching piston assembly, dividing the lower chamber into two chambers. The asymmetric flow channel switching piston assembly includes three annular damping flow channels, and different flow-changing valve plates are set at the beginning and end of the annular damping flow channels, so that the adaptive flow channel switching asymmetric magnetorheological damper can adaptively change the combination mode of the flow channels according to the direction of motion. The asymmetric flow channel switching piston assembly includes: a piston bottom end cap (2), an outer lower magnetic guide plate (9), an inner coil frame (10), an outer coil frame (11), a top diversion valve plate (16), a piston top end cap (34), an inner upper magnetic guide plate (37), an outer upper magnetic guide plate (38), an outer excitation coil (40), an inner excitation coil (41), an inner lower magnetic guide plate (43), a bottom diversion valve plate (44), an outer coil insulation layer (52), and an inner coil insulation layer (53); the inner coil... The coil frame (10), the internal excitation coil (41), and the internal coil insulation layer (53) are disposed between the internal upper magnetic plate (37) and the internal lower magnetic plate (43); the bottom diversion valve plate (44) is disposed between the piston bottom end cap (2) and the internal lower magnetic plate (43); the external coil frame (11), the external excitation coil (40), and the external coil insulation layer (52) are disposed between the external lower magnetic plate (9) and the external upper magnetic plate (38); the top diversion valve plate (16) is disposed between the external upper magnetic plate (38) and the piston top end cap (34); The piston bottom end cap (2) is provided with two sets of circumferentially distributed axial annular flow channel grooves: the selective inner flow channel groove (201) and the normally open outer flow channel groove (202); the combination of the outer coil skeleton (11), the outer lower magnetic plate (9) and the outer upper magnetic plate (38), the outer excitation coil (40) and the outer coil insulation layer (52) provided on the circumferential outer surface of the outer excitation coil (40) constitutes the external magnetic field generating component; The internal magnetic field generating assembly is composed of an internal coil frame (10), an internal lower magnetic plate (43), an internal upper magnetic plate (37), an internal excitation coil (41), and an internal coil insulation layer (53) disposed on the circumferential outer surface of the internal excitation coil (41). The outer surface of the external magnetic field generating component and the inner surface of the piston outer cylinder (36) form a first damping flow channel (54); the inner surface of the external magnetic field generating component and the outer surface of the internal magnetic field generating component form a second damping flow channel (55); in the internal magnetic field generating component, the inner lower magnetic plate (43) is provided with a circumferentially distributed inner through-flow channel groove (4301), and the inner upper magnetic plate (37) is provided with an inner through-flow channel groove (3701) whose axial projection position coincides with the inner through-flow channel groove (4301). The inner through-flow channel groove (4301), the inner through-flow channel groove (3701), the outer surface of the middle piston core (18), and the inner surface of the internal coil skeleton (10) together form a third damping flow channel (56). The bottom diversion valve plate (44) is provided with two sets of circumferentially distributed axial annular flow channel grooves: the bottom valve inner flow channel groove (4401) and the bottom valve outer flow channel groove (4402). Each bottom valve inner flow channel groove (4401), each bottom valve outer flow channel groove (4402) and each normally open outer flow channel groove (202) have no overlapping area, so as to ensure that the bottom diversion valve plate (44) can completely close the selected inner flow channel groove (201) during the stretching stroke section to realize diversion; one end of the bottom helical spring (7) is connected to the spring groove on the upper end face of the bottom diversion valve plate (44), and the other end is connected to the lower end face of the inner lower magnetic guide plate (43). The spring groove is connected; a set of circumferentially distributed axial annular flow channel grooves are provided on the top diversion valve plate (16): the top valve outer flow channel groove (1601), the axial projection position of the top valve outer flow channel groove (1601) coincides with the axial outer flow channel groove (3402) to ensure that the top valve outer flow channel groove (1601) will not block the axial outer flow channel groove (3402) during the compression stroke, thereby realizing flow diversion and pressure relief; a radial diversion groove (3801) connecting the first damping flow channel (54) and the second damping flow channel (55) is provided at the top of the internal upper magnetic guide plate (37) to realize the flow channel series connection during the stretching stroke.

2. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 1, characterized in that, The asymmetric flow channel switching piston assembly further includes: an inner plug (14), a middle piston core (18), a top piston core (19), a piston rod (31), an outer piston cylinder (36), a bottom piston core (46), and an outer plug (47); the outer piston cylinder (36) is provided on the outermost side of the piston bottom end cap (2), and the remaining parts are located inside the piston outer cylinder (36), and are divided into inner and outer rings; the inner ring parts are coaxially located at the center of the piston bottom end cap (2), and from bottom to top are the bottom piston core (46), the inner lower guide, and the outer piston core (46). The piston consists of a magnetic plate (43), a middle piston core (18), an inner upper magnetic guide plate (37), a top piston core (19), and a piston rod (31). The outer plug (47) is located at the bottom of the bottom piston core (46), and the inner plug (14) is located at the bottom of the middle piston core (18). The outer ring parts are coaxially located at the edge of the piston bottom end cap (2), and from bottom to top, they are the outer lower magnetic guide plate (9) and the outer upper magnetic guide plate (38). The piston top end cap (34) is located at the top of the piston outer cylinder (36) and is used to lock all internal parts.

3. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 2, characterized in that: The lower outer magnetic guide plate (9) is installed in the annular positioning groove on the upper end face of the piston bottom end cover (2); the outer coil frame (11) is set in the fixed groove between the coaxially mounted lower outer magnetic guide plate (9) and the upper outer magnetic guide plate (38), close to the circumferential inner surface of the lower outer magnetic guide plate (9) and the upper outer magnetic guide plate (38). The upper outer magnetic guide plate (38) is positioned by the limiting boss on the inner surface of the piston outer cylinder (36), and the limiting boss on the inner surface of the piston outer cylinder (36) is provided with several circumferentially distributed edge annular flow channel grooves (3601); the outer surface of the outer coil frame (11), the upper end face of the lower outer magnetic guide plate (9) and the lower end face of the upper outer magnetic guide plate (38) together form the first winding groove, and the external excitation coil (40) is wound in the first winding groove.

4. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 3, characterized in that: A first positioning pin (5) is installed in the positioning pin hole on the lower end face of the outer lower magnetic guide plate (9) and the upper end face of the annular positioning groove of the piston bottom end cover (2) to ensure that there is no relative rotation between the outer lower magnetic guide plate (9) and the piston bottom end cover (2); a wire hole (204) and a wire groove (205) are provided at the opposite position of the positioning pin hole on the lower end face of the piston bottom end cover (2). The wire hole (204) passes through the entire piston bottom end cover (2) for the lead-out of the external coil lead (45).

5. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 3, characterized in that: The bottom piston core (46) is mounted to the inner circular surface of the piston bottom end cap (2) through the positioning boss at the bottom end. The inner lower magnetic plate (43) is coaxially mounted to the positioning boss at the upper end of the bottom piston core (46). Then, the bottom piston core (46) and the inner lower magnetic plate (43) are mounted to the lower end face of the middle piston core (18) through the thread at the upper end of the bottom piston core (46). The inner upper magnetic plate (37) is coaxially mounted to the positioning boss at the lower end of the top piston core (19). Then, the top piston core (19) and the inner upper magnetic plate (37) are mounted to the upper end face of the middle piston core (18) through the thread at the lower end of the top piston core (19). The inner coil frame (10) is set in the fixing groove between the inner lower magnetic plate (43) and the inner upper magnetic plate (37) mounted coaxially, close to the circumferential inner surface of the inner lower magnetic plate (43) and the inner upper magnetic plate (37).

6. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 5, characterized in that: The inner plug O-ring (13) is installed into the sealing groove on the outer surface of the inner plug (14). The inner plug (14) is located in the stepped groove at the bottom of the middle piston core (18) and locked by the upper end face of the bottom piston core (46). The inner lower magnetic guide plate (43) and the bottom piston core (46) are respectively provided with overlapping wire holes and lead holes for the lead wires (42) of the internal coil. At the same time, the corresponding pin holes between the middle piston core (18) and the inner lower magnetic guide plate (43) are provided with second positioning. Pin (8) is used to ensure that there is no relative rotation between the inner lower magnetic plate (43) and the middle piston core (18); the outer plug O-ring (3) is installed in the sealing ring groove on the outer surface of the outer plug (47), and the outer plug (47) is installed in the stepped groove at the bottom of the bottom piston core (46); the outer surface of the inner coil skeleton (10), the upper end face of the inner lower magnetic plate (43) and the lower end face of the inner upper magnetic plate (37) together form the second winding groove, and the inner excitation coil (41) is wound in the second winding groove.

7. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 2, characterized in that: A stop ring (32) is provided in the circular groove on the outer surface of the piston rod (31), and a stop ring pad (20) is provided in the stepped groove inside the piston top end cap (34). The stop ring pad (20) contacts the stop ring (32) to achieve axial positioning of the piston rod (31). A piston rod O-ring (33) is provided in the sealing ring groove on the lower end and circumferential outer surface of the piston rod (31) to achieve sealing between the top piston core (19) and the piston rod (31). Two sets of circumferentially distributed annular flow channel grooves are provided on the piston top end cap (34): radial inner flow channel groove (3401) and axial outer flow channel groove (3402). The piston bottom end cap (2) and the piston top end cap (34) are fixed to the bottom and top of the piston outer cylinder (36) respectively by threads and end cap snap rings (35) to lock the internal parts.

8. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 1, characterized in that: The inner guide band (4) and the outer guide band (6) of the bottom diversion valve plate are respectively set in the grooves of the inner and outer circumferential surfaces of the bottom diversion valve plate (44); the bottom diversion valve plate (44) is coaxially set between the outer guide surface of the bottom of the bottom piston core (46) and the inner guide surface of the bottom of the outer lower magnetic guide plate (9); the top diversion valve plate (16) is coaxially set on the inner surface above the limiting boss of the piston outer cylinder (36); The outer guide band (15) of the top diversion valve plate is set in the groove on the outer circumferential surface of the top diversion valve plate (16). The inner surface of the top diversion valve plate (16) and the outer surface of the top piston core (19) together form the top inner flow channel groove (57). One end of the top helical spring (17) is connected to the spring groove on the lower end face of the top diversion valve plate (16), and the other end is connected to the spring groove on the upper end face of the inner upper magnetic guide plate (37).

9. The asymmetric magnetorheological damper with adaptive flow channel switching according to claim 2, characterized in that: The external excitation coil (40) passes through two external coil leads (45) through the wire groove on the lower magnetic plate (9), through the wire hole (204) of the piston bottom end cap (2) to the lower end face of the piston bottom end cap (2), then through the embedded wire groove (205) on the lower end face of the piston bottom end cap (2) to the metal connecting fork at the lower end of the outer plug (47), and finally through the transition lead (12) at the upper end of the outer plug (47) to the metal connecting fork at the lower end of the inner plug (14); the internal excitation coil (41) passes through two internal coil leads (45) through the wire groove on the lower magnetic plate (9), through the wire hole (204) of the piston bottom end cap (2) to the lower end face of the piston bottom end cap (2), and then through the embedded wire groove (205) on the lower end face of the piston bottom end cap (2) to the metal connecting fork at the lower end of the inner plug (14); the internal excitation coil (41) passes through two internal coil leads (45) through the wire groove on the lower magnetic plate (9), ... 2) The wire passes through the axial wire groove on the inner lower magnetic plate (43), through the radial wire hole on the inner lower magnetic plate (43), and then through the radial lead hole of the bottom piston core (46) to connect to the metal connecting fork at the lower end of the inner plug (14). Finally, it is led out to the outside of the damper through the inner through hole of the middle piston core (18), the top piston core (19) and the piston rod (31) via the outer lead (30). The outer excitation coil (40), the outer coil lead (45), the inner excitation coil (41) and the inner coil lead (42) are all covered with insulating material.

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