A controllable damping gap type magneto-rheological damper

Abstract

The utility model provides a controllable damping gap type magneto rheological damper mainly includes: piston rod, excitation piston, shape memory alloy ring, ceramic fiber reinforced metal aerogel, heating resistance, control valve, excitation coil, floating piston and damper cylinder body etc., shape memory alloy ring multilayer coaxial embedding is placed in the damping gap, the heating resistance is built -in in each layer ring, generates joule heat after electrification and triggers shape memory alloy to change phase and expand, shape memory alloy ring interlayer fills ceramic fiber reinforced metal aerogel, effectively insulates heat and transmits deformation, realizes the combination adjustment of single -layer, double -deck or three -layer damping gap through control valve, thereby realizes the multistage controllable of damping gap under different working conditions, this structure combines the magnetic control characteristic of excitation coil to magneto rheological fluid, significantly expands the adjustable range of damping gap, effectively avoids magneto rheological fluid settlement blockage simultaneously, has the characteristics of fast response, low energy consumption, high reliability, especially suitable for automobile suspension system and rail transit shock absorber.

Description

Technical Field

[0001] This utility model relates to a magnetorheological damper, and more particularly to a controllable damping gap type magnetorheological damper. Background Technology

[0002] Based on the intelligent rheological properties of magnetorheological materials, magnetorheological dampers exhibit three core advantages: First, the damping force can be rapidly switched in stages and continuously and reversibly adjusted, significantly improving the yield stress. Second, the damping force can be controlled in a wide range, in real time, and with precision by adjusting the excitation current with low power consumption. Third, with the aforementioned rapid response and wide range of controllable damping force, it has become an ideal actuator for achieving efficient semi-active vibration control and is widely used in key areas such as vehicle suspension system optimization, seismic reinforcement of building structures, and vibration reduction of precision instruments / industrial robotic arms.

[0003] Currently, the effective working damping gap of magnetorheological dampers is generally a single annular gap of fixed size. To expand the adjustable range of its output damping force, existing technologies mainly rely on two approaches: First, while maintaining a constant excitation current, the magnetic induction intensity within the damping gap is increased to approach the magnetic saturation limit of the magnetorheological fluid. A typical method is to reduce the radial dimension of the annular damping gap. However, this design is prone to gap blockage due to magnetorheological fluid particle settling after long-term static placement, causing damper failure. Second, while keeping the damping gap geometry unchanged, the apparent shear stress of the magnetorheological fluid is directly enhanced by increasing the excitation current intensity. However, this will cause a sharp increase in coil energy consumption, accompanied by serious magnetic saturation and overheating problems, which not only reduces energy efficiency but also accelerates magnetorheological fluid aging, restricting the long-term stability of the system. Both of these solutions are difficult to simultaneously meet the comprehensive requirements of wide-range damping adjustment, low zero-field basic damping, anti-settlement reliability, and energy efficiency optimization due to the rigid mechanical structure and the bottleneck of electrothermal energy consumption. Summary of the Invention

[0004] To overcome the problems existing in the background technology, this utility model proposes a controllable damping gap type magnetorheological damper for achieving controllable damping gap adjustment. Its core structure consists of three layers of coaxially nested shape memory alloy rings placed in the damping gap. Each layer of shape memory alloy rings embeds a heating resistor. When energized, the Joule heat generated is absorbed by the shape memory alloy ring, triggering a controllable phase transformation expansion from martensite to austenite. Ceramic fiber-reinforced metal aerogel is filled between adjacent shape memory alloy rings. This composite material also possesses ultra-low thermal conductivity, which can block interlayer thermal crosstalk and achieve independent temperature control. Each layer of shape memory alloy rings has a control valve. By controlling multiple levels of control valves, various damping gaps can be achieved, such as opening a single layer to drive the minimum damping gap under different operating conditions, or combining two or three layers to open medium / large flow channels, forming damping gaps of different sizes. The entire system has significant energy-saving benefits and strong adaptability, making it particularly suitable for scenarios such as rapid graded damping gap adjustment in automotive adaptive suspension for bumpy road conditions.

[0005] A controllable damping gap type magnetorheological damper is characterized by comprising: a piston rod (1), a sealing ring I (2), a damper left end cap (3), a screw I (4), a ceramic fiber reinforced metal aerogel (5), a screw II (6), a sealing ring II (7), a shape memory alloy ring (8), an excitation coil (9), a screw III (10), a heating resistor (11), an excitation piston right end cap (12), a nut (13), a floating piston (14), a sealing ring III (15), a right lifting lug (16), a damper right end cap (17), a screw IV (18), a sealing ring IV (19), a damper cylinder (20), an excitation piston (21), a control valve (22), an excitation piston left end cap (23), a damping gap (24), a sealing ring V (25), and a left lifting lug (26).

[0006] The left lifting lug (26) is machined with internal threads, and the piston rod (1) is machined with external threads. The piston rod (1) is tightly connected to the internal threads of the left lifting lug (26) through the machined external threads. The left end cover (3) of the damper is machined with a circular through hole. The left end cover (3) of the damper is clearance-fitted with the piston rod (1) through the machined circular through hole. The left end cover (3) of the damper is machined with a circular groove. The sealing ring I (2) is sealed through the circular groove machined in the left end cover (3) of the damper. The left end cover (3) of the damper is fixedly connected to the damper cylinder (20) by screw I (4). The left end cover (23) of the excitation piston is connected to the excitation piston by screw II (6). The magnetic piston (21) is fixedly connected. The right end cap (12) of the excitation piston is fixedly connected to the excitation piston (21) by screw III (10). The center of the left end face of the excitation piston (21) is machined with an internal thread hole. The piston rod (1) is fastened to the excitation piston (21) by a thread. The outer surface of the right end of the excitation piston (21) is machined with an external thread. The excitation piston (21) is fastened to the nut (13) by a thread. The floating piston (14) is placed below the excitation piston (21). Two circular grooves are machined on each side of the floating piston (14). The sealing ring IV (19) passes through the circular grooves machined on both sides of the floating piston (14). The groove seals the damper cylinder (20). The right end cover (17) of the damper is tightly fitted to the damper cylinder (20) by screw IV (18). The right end cover (17) of the damper has a circular groove. The sealing ring V (25) seals the damper cylinder (20) through the circular groove of the right end cover (17). The right end of the right end cover (17) of the damper has an external thread, and the right lifting lug (16) has an internal thread. The right end cover (17) of the damper is fixedly connected to the right lifting lug (16) through the external thread. The excitation piston (21) has a circular groove inside. The excitation line The coil (9) is placed in the circular groove machined inside the excitation piston (21). The two leads of the excitation coil (9) pass through the lead groove in the excitation piston (21) and the corresponding lead hole on the left end cover (23) of the excitation piston, and are led out through the lead hole in the piston rod (1). Ceramic fiber reinforced metal aerogel (5) is embedded in the damping gap (24) of the excitation piston (21). Multiple layers of shape memory alloy rings (8) are arranged in the ceramic fiber reinforced metal aerogel (5). A heating resistor (11), a control valve (22) and ceramic fiber reinforced metal aerogel (5) are built between each layer of shape memory alloy rings (8).

[0007] The left end cover (3) of the damper, the left end cover (23) of the excitation piston and the damper cylinder (20) form a closed cavity I. The right end cover (12) of the excitation piston, the damper cylinder (20) and the floating piston (14) form a closed cavity II. The floating piston (14), the damper cylinder (20) and the right end cover (17) of the damper form a closed cavity III. The closed cavities I and II are filled with magnetorheological fluid, and the closed cavity III is filled with compressed gas. When the piston rod (1) is stretched in the axial direction, the magnetorheological fluid in the closed cavity I enters the closed cavity II through the damping gap (24). When the piston rod (1) is compressed in the axial direction, the magnetorheological fluid in the closed cavity II enters the closed cavity I through the damping gap (24). When the piston rod (1) moves in the axial direction, the volumes of the closed cavities I and II will change accordingly. At this time, the floating piston (14) will achieve volume compensation by floating left and right in the axial direction.

[0008] Compared with the prior art, the advantages of this utility model are:

[0009] (1) This utility model incorporates a cascaded drive structure of multi-layer shape memory alloy rings and ceramic fiber reinforced metal aerogel within the damping gap, and achieves multi-level control of the damping gap size by controlling the opening and closing of the valve. Combined with the on / off combination of the excitation coil and the multi-layer shape memory alloy rings, multiple damping control modes are formed. When the excitation current and the thermal drive parameters of the shape memory alloy are adjusted in synergy, the dynamic adjustable range of the damping force is extended to many times that of the traditional fixed gap structure without changing the size of the excitation piston. Furthermore, the maximum flow channel diameter design under zero current conditions effectively avoids the risk of magnetorheological fluid sedimentation and blockage, ensuring long-term maintenance-free operation of the damper.

[0010] (2) The interlayer ceramic fiber reinforced metal aerogel of this invention effectively blocks the interlayer heat conduction during the operation of each layer of shape memory alloy rings, so that the temperature change of each layer of shape memory alloy ring is independently controlled within the phase transition temperature range. The multilayer shape memory alloy rings only need an instantaneous pulse current to trigger the phase transition, which reduces the heat generation of the system from the source. This reduces the temperature change of the core working area of ​​the damper compared with the traditional solenoid valve drive scheme, significantly delays the high-temperature degradation of the magnetorheological fluid, and improves the output stability under high-temperature conditions.

[0011] (3) The multi-layer shape memory alloy ring of this utility model has a built-in Joule thermal resistor and an external support structure made of a low heat capacity titanium alloy frame, which is combined with the aerogel layer. This thermo-mechanical coupling topology allows the multi-layer shape memory alloy ring to be triggered by an instantaneous pulse current for independent and precise phase change expansion. The expansion displacement is transmitted without loss through the ultra-low thermal conductivity and high elasticity aerogel layer, which drives the corresponding control valve to control the size of the damping gap, thereby realizing the rapid multi-level adjustment of the damping gap. The entire system has no mechanical moving parts, has a simple structure and good energy-saving effect, and particularly meets the high reliability and fast response requirements of automobile suspension to cope with continuous bumpy road conditions and rail transit bogies to resist impact. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] Figure 2 This is a cross-sectional view of the excitation piston structure of this utility model.

[0014] Figure 3 This is a schematic diagram of the controllable damping gap structure of this utility model. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0016] like Figure 1 As shown, this utility model includes: piston rod (1), sealing ring I (2), damper left end cover (3), screw I (4), ceramic fiber reinforced metal aerogel (5), screw II (6), sealing ring II (7), shape memory alloy ring (8), excitation coil (9), screw III (10), heating resistor (11), excitation piston right end cover (12), nut (13), floating piston (14), sealing ring III (15), right lifting lug (16), damper right end cover (17), screw IV (18), sealing ring IV (19), damper cylinder (20), excitation piston (21), control valve (22), excitation piston left end cover (23), damping gap (24), sealing ring V (25), and left lifting lug (26).

[0017] The left lifting lug (26) is machined with internal threads, and the piston rod (1) is machined with external threads. The piston rod (1) is tightly connected to the internal threads of the left lifting lug (26) through the machined external threads. The left end cover (3) of the damper is machined with a circular through hole. The left end cover (3) of the damper is clearance-fitted with the piston rod (1) through the machined circular through hole. The left end cover (3) of the damper is machined with a circular groove. The sealing ring I (2) is sealed through the circular groove machined in the left end cover (3) of the damper. The left end cover (3) of the damper is fixedly connected to the damper cylinder (20) by screw I (4). The left end cover (23) of the excitation piston is connected to the excitation piston by screw II (6). The magnetic piston (21) is fixedly connected. The right end cap (12) of the excitation piston is fixedly connected to the excitation piston (21) by screw III (10). The center of the left end face of the excitation piston (21) is machined with an internal thread hole. The piston rod (1) is fastened to the excitation piston (21) by a thread. The outer surface of the right end of the excitation piston (21) is machined with an external thread. The excitation piston (21) is fastened to the nut (13) by a thread. The floating piston (14) is placed below the excitation piston (21). Two circular grooves are machined on each side of the floating piston (14). The sealing ring IV (19) passes through the circular grooves machined on both sides of the floating piston (14). The groove seals the damper cylinder (20). The right end cover (17) of the damper is tightly fitted to the damper cylinder (20) by screw IV (18). The right end cover (17) of the damper has a circular groove. The sealing ring V (25) seals the damper cylinder (20) through the circular groove of the right end cover (17). The right end of the right end cover (17) of the damper has an external thread, and the right lifting lug (16) has an internal thread. The right end cover (17) of the damper is fixedly connected to the right lifting lug (16) through the external thread. The excitation piston (21) has a circular groove inside. The excitation line The coil (9) is placed in the circular groove machined inside the excitation piston (21). The two leads of the excitation coil (9) pass through the lead groove in the excitation piston (21) and the corresponding lead hole on the left end cover (23) of the excitation piston, and are led out through the lead hole in the piston rod (1). Ceramic fiber reinforced metal aerogel (5) is embedded in the damping gap (24) of the excitation piston (21). Multiple layers of shape memory alloy rings (8) are arranged in the ceramic fiber reinforced metal aerogel (5). A heating resistor (11), a control valve (22) and ceramic fiber reinforced metal aerogel (5) are built between each layer of shape memory alloy rings (8).

[0018] The left end cover (3) of the damper, the left end cover (23) of the excitation piston and the damper cylinder (20) form a closed cavity I. The right end cover (12) of the excitation piston, the damper cylinder (20) and the floating piston (14) form a closed cavity II. The floating piston (14), the damper cylinder (20) and the right end cover (17) of the damper form a closed cavity III. The closed cavities I and II are filled with magnetorheological fluid, and the closed cavity III is filled with compressed gas. When the piston rod (1) is stretched in the axial direction, the magnetorheological fluid in the closed cavity I enters the closed cavity II through the damping gap (24). When the piston rod (1) is compressed in the axial direction, the magnetorheological fluid in the closed cavity II enters the closed cavity I through the damping gap (24). When the piston rod (1) moves in the axial direction, the volumes of the closed cavities I and II will change accordingly. At this time, the floating piston (14) will achieve volume compensation by floating left and right in the axial direction.

[0019] Figure 2 This is a cross-sectional view of the excitation piston structure of this utility model, which consists of an excitation coil (9), an excitation piston (21), and damping gaps (24). The excitation piston (21) has an excitation coil (9) embedded inside, and multiple damping gaps (24) in its circumference. Each damping gap (24) integrates a controllable damping gap structure consisting of ceramic fiber reinforced metal aerogel (5), shape memory alloy ring (8), heating resistor (11), and control valve (22). By controlling the heating resistor (11) and control valve (22), four control modes are formed: mode 1, the heating resistor (11) is not energized and all levels of control valve (22) are closed; mode 2, the heating resistor (11) is energized and all levels of control valve (22) are closed; mode 3, the heating resistor (11) is energized and the first level control valve (22) is open and the second level control valve (22) is closed; mode 4, the heating resistor (11) is energized and the first level control valve (22) is open and the second level control valve (22) is open. When the heating resistor (11) and control valve (22) are controllable, a control mode in which the damping gap (24) is continuously adjustable is formed, providing a multi-mode damping gap (24) adjustment method for adjusting the damping gap.

[0020] Figure 3This is a cross-sectional view of the controllable damping gap structure of this utility model, which consists of ceramic fiber reinforced metal aerogel (5), shape memory alloy ring (8), heating resistor (11), and control valve (22). The heating resistor (11) and control valve (22) are both controlled by instantaneous pulse current. When the heating resistor (11) is activated, it generates Joule heat, triggering the phase change expansion of the single-layer shape memory alloy ring (8), driving the deformation of the contacting ceramic fiber reinforced metal aerogel (5), and reducing the effective cross-sectional area of ​​the damping gap (24). When the control valve (22) is not open, the heat is isolated by the ceramic fiber reinforced metal aerogel (5) between the two adjacent layers of shape memory alloy ring (8). When the control valve (22) is further opened, a cross-layer heat flow path is constructed, so that the heat is conducted between the multiple layers of shape memory alloy ring (8), and the synchronous thermal expansion increases the deformation degree of the ceramic fiber reinforced metal aerogel (5). The damping gap (24) will further reduce the channel size, realizing the rapid multi-level adjustment of the damping gap (24).

[0021] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A controllable-damping-gap magnetorheological damper, characterized in that include: Piston rod (1), sealing ring I (2), damper left end cap (3), screw I (4), ceramic fiber reinforced metal aerogel (5), screw II (6), sealing ring II (7), shape memory alloy ring (8), excitation coil (9), screw III (10), heating resistor (11), excitation piston right end cap (12), nut (13), floating piston (14), sealing ring III (15), right lifting lug (16), damper right end cap (17), screw IV (18), sealing ring IV (19), damper cylinder (20), excitation piston (21), control valve (22), excitation piston left end cap (23), damping gap (24), sealing ring V (25), left lifting lug (26), left lifting lug (26) The piston rod (1) is machined with an internal thread, and the piston rod (1) is machined with an external thread. The piston rod (1) is tightly connected to the internal thread of the left lifting lug (26) through the machined external thread. The left end cover (3) of the damper is machined with a circular through hole. The left end cover (3) of the damper is clearance-fitted with the piston rod (1) through the machined circular through hole. The left end cover (3) of the damper is machined with a circular groove. The sealing ring I (2) is sealed through the circular groove machined on the left end cover (3) of the damper. The left end cover (3) of the damper is fixedly connected to the damper cylinder (20) by screw I (4). The left end cover (23) of the excitation piston is fixedly connected to the excitation piston (21) by screw II (6). The right end cover (12) of the excitation piston is fixed to the excitation piston (21) by screw III (10). The excitation piston (21) has an internal threaded hole machined at the center of its left end face. The piston rod (1) is fastened to the excitation piston (21) by a thread. The excitation piston (21) has an external thread machined on its right outer surface. The excitation piston (21) is fastened to the nut (13) by a thread. The floating piston (14) is placed below the excitation piston (21). Two circular grooves are machined on each side of the floating piston (14). The sealing ring IV (19) seals the damper cylinder (20) through the circular grooves machined on both sides of the floating piston (14). The damper right end cover (17) is tightly fitted to the damper cylinder (20) by screw IV (18). The damper right end cover (17) has a circular groove machined on it. The sealing ring V (25) seals the damper right end cover (17) through the circular grooves machined on both sides of the floating piston (14). The circular groove machined on the cover (17) seals the damper cylinder (20). The right end of the damper cover (17) has an external thread, and the right lug (16) has an internal thread. The right end of the damper cover (17) is fixedly connected to the right lug (16) through the external thread. The excitation piston (21) has a circular groove machined inside. The excitation coil (9) is placed in the circular groove machined inside the excitation piston (21). The two leads of the excitation coil (9) pass through the lead groove in the excitation piston (21) and the corresponding lead hole on the left end cover (23) of the excitation piston, and are led out through the lead hole in the piston rod (1). Ceramic fiber reinforced metal aerogel (5) is embedded in the damping gap (24) of the excitation piston (21).Multiple layers of shape memory alloy rings (8) are arranged within the ceramic fiber reinforced metal aerogel (5), with a heating resistor (11), a control valve (22), and the ceramic fiber reinforced metal aerogel (5) embedded between each layer of shape memory alloy rings (8).

2. The controllable damper gap type magneto-rheological damper according to claim 1, characterized in that: Four control modes are formed by controlling the heating resistor (11) and the control valve (22). In mode 1, the heating resistor (11) is not energized and all levels of control valve (22) are closed. In mode 2, the heating resistor (11) is energized and all levels of control valve (22) are closed. In mode 3, the heating resistor (11) is energized and the first level control valve (22) is open and the second level control valve (22) is closed. In mode 4, the heating resistor (11) is energized and the first level control valve (22) is open and the second level control valve (22) is open. When the heating resistor (11) and the control valve (22) are controllable, a control mode in which the damping gap (24) is continuously adjustable is formed, providing a multi-mode damping gap (24) adjustment method.

3. The controllable damper gap type magneto-rheological damper according to claim 1, characterized in that: The heating resistor (11) and the control valve (22) are both controlled by instantaneous pulse current. When the heating resistor (11) is activated, it generates Joule heat, which triggers the phase change expansion of the single-layer shape memory alloy ring (8), reduces the effective cross-sectional area of ​​the damping gap (24), and further opens the control valve (22). Heat is conducted between the multi-layer shape memory alloy rings (8), which increases the deformation degree of the ceramic fiber reinforced metal aerogel (5) and realizes rapid multi-level adjustment of the damping gap (24).

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