Nonlinear rigidity decoupling type magnetorheological damper

Abstract

The invention provides a nonlinear rigidity decoupling type magnetorheological damper which comprises an end cover and a cylinder cover and further comprises a cylinder body, a nonlinear assembly and a damping assembly. The end cover, the cylinder cover and the cylinder body are connected through screws, a closed cavity is formed between the cylinder cover and the cylinder body, the cavity is filled with magnetorheological fluid, and a nonlinear assembly and a damping assembly are arranged on the inner side of the cylinder body. The invention belongs to the technical field of vibration damping devices, through the arrangement of the nonlinear assembly, the piston body and the piston rod are in nonlinear rigidity connection, so that nonlinear dynamic characteristic decoupling of the magneto-rheological damper is achieved, and the high-frequency application range of the magneto-rheological damper is greatly widened; according to the damper, the upper baffle, the lower baffle and the piston rod are in threaded connection, the shape of the upper tower spring and the shape of the lower tower spring can be adjusted, the function of adjusting the initial equivalent connection rigidity of the piston body and the piston rod according to the vibration control requirement is achieved, and the damper can adapt to different vibration control requirements.

Description

Technical Field

[0001] The present invention relates to a non-linear stiffness decoupling type magneto-rheological damper, and specifically belongs to the technical field of vibration damping devices. Background Art

[0002] Spacecraft such as satellites are gradually developing towards being large-sized and flexible. However, the vibration problems of large spacecraft have had an adverse impact on the stability and control accuracy of the spacecraft; as an ideal semi-active vibration control actuator, magneto-rheological dampers have broad application prospects in the field of spacecraft vibration control.

[0003] In order to improve the performance of magneto-rheological dampers, magneto-rheological dampers with different structural forms have been studied and developed; multi-stage coil magneto-rheological dampers increase the number of coils, folded flow type magneto-rheological dampers increase the length of the damping channel, and hybrid magneto-rheological dampers combine two working modes to improve the output force of the magneto-rheological damper. Through the optimization and improvement of the above structural forms, the output force of the magneto-rheological damper can be improved. However, it is difficult to improve the high-frequency applicability of the magneto-rheological damper. The magneto-rheological damper will have a high-frequency hardening phenomenon under high-frequency vibration, and the dynamic stiffness of the magneto-rheological damper will increase significantly, which has an adverse impact on the vibration isolation performance of the vibration isolation system.

[0004] Comparing the published patent documents, publication number CN101725660A discloses a high-frequency decoupling type piston magneto-rheological damper, and publication number CN101446117 discloses a high-energy consumption self-decoupling type magneto-rheological damper. Among them, the piston and the piston rod are connected by an annular spring, and it is not stated whether the spring has non-linear characteristics. If the piston and the piston rod are connected by a linear spring, the connection stiffness cannot change with the relative displacement of the piston and the piston rod, which restricts the decoupling effect of the piston and the piston rod and further affects the vibration isolation performance of the magneto-rheological damper. Summary of the Invention

[0005] The purpose of the present invention is to provide a non-linear stiffness decoupling type magneto-rheological damper to solve the problem that the connection stiffness cannot change with the relative displacement and it is difficult to greatly expand the high-frequency application range of the magneto-rheological damper.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is: the invention includes an end cover and a cylinder head, and also includes a cylinder body, a non-linear component and a damping component; one side of the end cover is connected to the cylinder head, the other side of the cylinder head is connected to the cylinder body, screws are provided on the inner sides of the end cover, the cylinder head and the cylinder body, and the end cover, the cylinder head and the cylinder body are connected by screws. A sealed chamber is formed between the cylinder head and the cylinder body, the chamber is filled with magneto-rheological fluid, and a non-linear component and a damping component are arranged inside the cylinder body, and the non-linear component and the damping component are connected together.

[0007] Furthermore, the end cover, cylinder head and cylinder block are stably installed by screws, thereby improving the convenience of damper installation.

[0008] The damping assembly includes a piston rod and a piston body; the piston rod is arranged inside the cylinder head and the cylinder block. A sealing ring is arranged outside the connection between the cylinder head and the cylinder block of the piston rod. A piston body is arranged outside the middle part of the piston rod. A sealing ring is arranged at the connection between the piston body and the piston rod. The piston body is arranged inside the cylinder block;

[0009] The piston body and the cylinder block are made of magnetically conductive materials, and the piston rod is made of non-magnetically conductive materials.

[0010] Furthermore, the sealing rings enable the piston rod to have clearance fits with the cylinder head, the cylinder block and the piston body respectively, and realize sliding sealing.

[0011] The non-linear assembly includes an upper tower spring and a lower tower spring; an upper tower spring is arranged between the upper baffle and the piston body, and a lower tower spring is arranged between the lower baffle and the piston body. Both the upper tower spring and the lower tower spring are arranged outside the piston rod. Both the upper tower spring and the lower tower spring are in a compressed state. The initial compression amounts of the upper tower spring and the lower tower spring are the same, and the initial compression amounts of the upper tower spring and the lower tower spring are greater than the relative displacement between the piston body and the piston rod.

[0012] Furthermore, by changing the shapes of the upper tower spring and the lower tower spring, or adjusting the installation positions of the upper baffle and the lower baffle, the initial equivalent connection stiffness between the piston and the piston rod can be changed; at the same time, when the piston and the piston rod move relatively, the compression amount of one side tower spring becomes smaller, and the compression amount of the other side tower spring becomes larger, and the equivalent connection stiffness between the piston and the piston rod changes.

[0013] The damping assembly further includes a coil; a damping channel is formed between the outside of the piston body and the inside of the cylinder block. A coil is wound around the outside of the piston body, and a ring-shaped magnetic field magnetic force line will be formed around the coil.

[0014] Furthermore, when the coil is energized, a ring-shaped magnetic field magnetic force line will be formed around the coil, and the magnetorheological damper provides a controllable damping force, and the magnitude of the damping force changes with the change of the current magnitude.

[0015] The beneficial effects of the present invention are:

[0016] 1. For the non-linear stiffness decoupling type magnetorheological damper of the present invention, through the setting of the non-linear assembly, the piston body and the piston rod are connected with non-linear stiffness, thereby realizing the decoupling of the non-linear dynamic characteristics of the magnetorheological damper, and greatly broadening the high-frequency application range of the magnetorheological damper.

[0017] 2. The non-linear stiffness decoupling type magnetorheological damper of the present invention can adjust the initial equivalent connection stiffness between the piston and the piston rod according to the vibration control requirements, and can adapt to different vibration control requirements.

[0018] 3. The non-linear stiffness decoupling type magneto-rheological damper of the present invention can dynamically adjust the stiffness and damping. It has high stiffness and large damping under the conditions of low frequency and large amplitude, which is beneficial to vibration suppression; it has low stiffness and small damping under the conditions of high frequency and small amplitude, which is beneficial to vibration isolation, and comprehensively improves the vibration isolation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic three-dimensional structure diagram of the whole of the present invention;

[0020] Figure 2 is a schematic front sectional structure diagram of the whole of the present invention;

[0021] Figure 3 is a schematic diagram of the magnetic field line distribution of the present invention;

[0022] Figure 4 is a schematic diagram of the non-linear stiffness variables of the upper tower spring and the lower tower spring of the present invention.

[0023] 1. End cover; 2. Screw; 3. Cylinder head; 4. Cylinder body; 5. Piston rod; 6. Upper baffle; 7. Upper tower spring; 8. Piston; 9. Coil; 10. Lower tower spring; 11. Lower baffle; 12. Magnetic field line. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following will combine with the attached Figures 1-4 , and clearly and completely describe the technical solutions in the embodiments.

[0025] Detailed Embodiment 1: As Figures 1-2 shown, the whole damper is composed of an end cover 1, a cylinder head 3 and a cylinder body 4. The inner side of the cylinder body 4 is provided with a non-linear component and a damping component. The damper is installed between the base and the load. The end cover 1, the cylinder head 3 and the cylinder body 4 are stably installed and connected through screws 2, thereby improving the convenience and stability of the overall installation of the damper. When the base and the load vibrate, it will cause the piston body 8 and the cylinder body 4 to slide relatively. At this time, the magneto-rheological fluid in the sealed chamber formed between the cylinder head 3 and the cylinder body 4 will flow through the damping channel formed between the outside of the piston body 8 and the inner side of the cylinder body 4. The application range of the variable damper is broadened through the setting of the non-linear component;

[0026] A sealing ring is arranged on the outer side of the connection between the piston rod 5 and the cylinder head 3 and the cylinder body 4, and a sealing ring is arranged on the connection between the piston body 8 and the piston rod 5. Through the setting of the sealing ring, the piston rod 5 is in clearance fit with the cylinder head 3, the cylinder body 4 and the piston body 8 respectively, and sliding sealing is realized, thereby improving the stability of the structures of the piston rod 5 and the piston body 8.

[0027] On the outer sides of the piston rod 5, an upper baffle 6 and a lower baffle 11 are respectively connected by threads, so that the initial compression amounts of the upper tower spring 7 and the lower tower spring 10 can be adjusted, thereby changing the initial equivalent connection stiffness and damping between the piston body 8 and the piston rod 5, and being able to adapt to different vibration control requirements.

[0028] In addition, by changing the shapes of the upper tower spring and the lower tower spring, the initial equivalent connection stiffness and damping between the piston body 8 and the piston rod 5 are changed, and different vibration control requirements can be adapted.

[0029] Specific Embodiment 2: As Figures 2-4 shown, since an upper tower spring 7 is provided between the upper baffle 6 and the piston body 8, and a lower tower spring 10 is provided between the lower baffle 11 and the piston body 8, when the upper baffle 6 and the lower baffle 11 are adjusted, the upper tower spring 7 and the lower tower spring 10 will be compressed and stretched. The cooperation of the upper tower spring 7 and the lower tower spring 10 will drive the piston body 8 to move on the outer side of the piston rod 5, and at the same time ensure that the upper tower spring 7 and the lower tower spring 10 will not become disengaged, so that the relative displacement of the relative movement between the piston body 8 and the piston rod 5 is changed, and further the connection stiffness of the piston body 8 to the piston rod 5 is changed.

[0030] When the coil 9 is not energized, the magnetorheological damper provides a passive damping force; when the coil is energized, an annular magnetic field magnetic force line 12 will be formed around the coil, and the magnetorheological damper provides a controllable damping force, and the magnitude of the damping force changes with the change of the current magnitude.

[0031] When the vibration frequency is low, the vibration amplitude is large, the relative displacement between the piston body 8 and the piston rod 5 is large, and the equivalent connection stiffness of the upper tower spring 7 and the lower tower spring 10 is large. At this time, a large damping effect can be generated, which is beneficial to low-frequency vibration suppression.

[0032] When the vibration frequency is high, the vibration amplitude is small, the relative displacement between the piston body 8 and the piston rod 5 is small, and the equivalent connection stiffness of the upper tower spring 7 and the lower tower spring 10 is small. At this time, a small damping effect can be generated, which is beneficial to high-frequency vibration isolation.

[0033] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to be equivalent changed equivalent embodiments within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, according to the technical essence of the present invention, any simple modification, equivalent replacement and improvement of the above embodiments within the spirit and principle of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A nonlinear stiffness decoupling type magnetorheological damper, comprising an end cover (1) and a cylinder cover (3), characterized in that: Also includes a cylinder (4), a nonlinear component and a damping component; One side of the end cover (1) is connected to a cylinder cover (3), and the other side of the cylinder cover (3) is connected to a cylinder body (4). Screws (2) are arranged on the inner sides of the end cover (1), the cylinder cover (3) and the cylinder body (4). The end cover (1), the cylinder cover (3) and the cylinder body (4) are connected via the screws (2). A sealed chamber is formed between the cylinder cover (3) and the cylinder body (4), and the chamber is filled with magnetorheological fluid. A damping component and a nonlinear component are arranged on the inner side of the cylinder body (4), and the damping component and the nonlinear component are connected together.

2. The nonlinear stiffness decoupling magnetorheological damper according to claim 1, characterized in that: The damping assembly comprises a piston rod (5) and a piston body (8); A piston rod (5) is arranged on the inner side of the cylinder cover (3) and the cylinder body (4); a sealing ring is arranged on the outer side of the piston rod (5) at the connection between the cylinder cover (3) and the cylinder body (4); a piston body (8) is arranged on the outer side of the middle part of the piston rod (5); a sealing ring is arranged at the connection between the piston body (8) and the piston rod (5); and the piston body (8) is arranged on the inner side of the cylinder body (4).

3. The nonlinear stiffness decoupling magnetorheological damper according to claim 1, characterized in that: The damping assembly also includes a coil (9); A damping channel is formed between the outer side of the piston body (8) and the inner side of the cylinder body (4). A coil (9) is wound around the outer side of the piston body (8), and an annular magnetic field magnetic force lines (12) are formed around the coil (9).

4. The nonlinear stiffness decoupling magnetorheological damper according to claim 1, characterized in that: The damping assembly also includes an upper baffle (6) and a lower baffle (11); An upper baffle (6) is arranged on one side of the piston body (8), and a lower baffle (11) is arranged on the other side of the piston body (8). Both the upper baffle (6) and the lower baffle (11) are arranged on the outside of the piston rod (5).

5. The nonlinear stiffness decoupling magnetorheological damper according to claim 1, characterized in that: The nonlinear component includes an upper tower spring (7) and a lower tower spring (10); An upper tower spring (7) is arranged between the upper baffle plate (6) and the piston body (8), and a lower tower spring (10) is arranged between the lower baffle plate (11) and the piston body (8). The upper tower spring (7) and the lower tower spring (10) are both arranged outside the piston rod (5). The upper tower spring (7) and the lower tower spring (10) are both in a compressed state. The initial compression amounts of the upper tower spring (7) and the lower tower spring (10) are the same, and the initial compression amounts of the upper tower spring (7) and the lower tower spring (10) are greater than the relative displacement between the piston body (8) and the piston rod (5).

6. The nonlinear stiffness decoupling magnetorheological damper according to claim 2, characterized in that: The piston body (8) and the cylinder body (4) are made of magnetic conductive materials, and the piston rod (5) is made of non-magnetic conductive materials.

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