Magnetorheological damper with rigidity and damping being variable at same time

Abstract

The utility model discloses a magneto-rheological damper with variable rigidity and damping simultaneously. The magneto-rheological damper is mainly composed of a support, an end cover, a cylinder barrel, a piston rod, a reel, a piston sleeve, a baffle, a magnet exciting coil, an outer spring, an inner spring and the like. The damper cylinder barrel is filled with magnetorheological fluid, and an annular liquid flow channel is formed between the piston sleeve and the winding frame. By adjusting the current of the magnet exciting coil, the damping of a liquid flow channel can be changed based on the magnetorheological effect, and continuous and variable output damping force is achieved; a piston head assembly composed of the winding frame, the piston sleeve and the baffle can slide relative to the piston rod and is fixed through the inner springs at the two ends. The outer spring and the inner spring have different rigidity coefficients and are connected in parallel. The relative displacement between the piston head assembly and the piston rod can be adjusted by controlling the damping force, and then the continuous variable system rigidity is achieved. The magneto-rheological damper can control rigidity and damping at the same time, and is particularly suitable for vibration reduction occasions with the wide frequency change range.

Description

Technical Field

[0001] This utility model relates to a magnetorheological damper, and more particularly to a magnetorheological damper with variable stiffness and damping. Background Technology

[0002] Vibration control is a key technology in fields such as machinery, vehicles, and construction, directly affecting the safety, stability, and reliability of systems. Traditional passive dampers, due to their non-adjustable damping force, struggle to meet vibration reduction requirements under varying operating conditions. Magnetorheological dampers, as a semi-active damper, can achieve controllable adjustment of the output damping force by adjusting the current in the excitation coil based on the magnetorheological effect, thereby changing the damping of the fluid flow channel. Therefore, magnetorheological dampers can dynamically adjust the output damping force according to real-time operating conditions, significantly improving vibration reduction performance and representing an important direction for the development of vibration control technology.

[0003] To improve the dynamic performance of magnetorheological dampers, various novel damper structures have been designed and developed. Among these, dual-coil, triple-coil, and multi-coil structures have been designed to improve magnetic field utilization; and composite, multi-stage ring, and meandering flow channel structures have been designed to extend the effective damping gap. While these improvements effectively enhance damping force output and broaden the adjustable range, their impact on overall vibration reduction performance remains relatively limited. In practical applications, systems often face external vibrations with varying frequencies. When the vibration frequency approaches the system's natural frequency, resonance is easily induced, leading to intensified vibration. However, traditional magnetorheological dampers can only adjust damping, not stiffness, thus hindering effective vibration reduction.

[0004] Based on this, this utility model proposes a magnetorheological damper with simultaneously variable stiffness and damping, which can control stiffness and damping at the same time to meet the vibration reduction requirements in a wide frequency range. Summary of the Invention

[0005] To overcome the problems of the magnetorheological dampers described in the background art and to further meet the practical application requirements of magnetorheological dampers, this utility model proposes a magnetorheological damper with simultaneously variable stiffness and damping. The piston head assembly of this damper adopts a valve-type structure, mainly composed of a winding frame, a piston sleeve, and a baffle. An annular fluid flow channel is formed between the winding frame and the piston sleeve. By adjusting the excitation coil current, the damping of the fluid flow channel can be changed in real time based on the magnetorheological effect, achieving continuous adjustment of the output damping force. Furthermore, the piston head assembly maintains a tight clearance fit with the inner wall of the cylinder, effectively ensuring the coaxiality of the piston rod during reciprocating motion, thereby significantly improving the working stability of the damper. Simultaneously, a clearance fit is used between the piston head assembly and the piston rod, allowing relative sliding between them. An inner spring is fixed to each end of the piston head assembly. An outer spring is fitted outside the damper cylinder, with its two ends connected to the left and right supports, respectively. The outer spring and the inner spring are set with different stiffness coefficients, forming a parallel relationship. By controlling the magnitude of the damping force, the relative displacement between the piston head assembly and the piston rod can be adjusted, thereby achieving continuous adjustment of the system stiffness. Compared with traditional magnetorheological dampers, this damper can achieve simultaneous continuous adjustment of both stiffness and damping, making it more suitable for vibration reduction applications with a wide frequency variation range.

[0006] The technical solution adopted by this utility model to solve its technical problem includes: a left support (1), piston rod I (2), outer spring (3), left end cover (4), cylinder (5), piston rod II (6), inner spring I (7), left baffle (8), piston sleeve (9), excitation coil (10), winding frame (11), right baffle (12), inner spring II (13), piston rod III (14), right end cover (15), and right support (16); the left support (1) and piston rod I (2) are fixedly connected by threads; the right side of the left end cover (4) is clearance-fitted with the inner circumference of the cylinder (5) and sealed by a sealing ring; the left end cover (4) and cylinder (5) are fixedly connected by screws; a circular through hole is machined in the middle of the left end cover (4), and the piston rod I (2) The piston rod I (2) and piston rod II (6) are fixedly connected by threads; the winding frame (11) has a circular through hole in the middle, and the piston rod II (6) is fitted with the inner surface of the circular through hole of the winding frame (11) with a clearance fit and is sealed by a sealing ring; the outer surface of the winding frame (11) is fitted with the inner circumference of the piston sleeve (9); the outer surface of the piston sleeve (9) is fitted with the inner circumference of the cylinder (5) with a clearance fit and is sealed by a sealing ring; the right end face of the left baffle (8) is tightly fitted with the left end face of the winding frame (11) and the left end face of the piston sleeve (9); the left baffle (8) and piston sleeve (9) are fixedly connected by screws; the left end face of the winding frame (11) is fitted with the inner spring I (7) The right side is fixedly connected. The inner surface of the inner spring I (7) is clearance-fitted with the outer surface of the piston rod II (6). The left side of the inner spring I (7) is fixedly connected with the right end face of the piston rod I (2). The left end face of the right baffle (12) is tightly fitted with the right end face of the winding frame (11) and the right end face of the piston sleeve (9). The right baffle (12) and the piston sleeve (9) are fixedly connected by screws. The piston rod II (6) and the piston rod III (14) are fixedly connected by threads. The right end face of the winding frame (11) is fixedly connected with the left side of the inner spring II (13). The inner surface of the inner spring II (13) is clearance-fitted with the outer surface of the piston rod II (6). The right side of the inner spring II (13) is fixedly connected with the left end face of the piston rod III (14). The left side of the right end cover (15) is clearance-fitted with the inner circumferential surface of the cylinder (5). The right support (16) and the right end cover (15) are fitted together and sealed with a sealing ring; the left end face of the right support (16) and the right end cover (15) are tightly fitted together; the right support (16), the right end cover (15) and the cylinder (5) are fixedly connected by screws; a circular through hole is machined in the middle of the right end cover (15), the piston rod III (14) is fitted with the inner surface of the circular through hole of the right end cover (15) with a clearance fit and sealed with a sealing ring; the right end face of the left support (1) is fixedly connected to the left side of the outer spring (3), the inner surface of the outer spring (3) is fitted with the outer surface of the cylinder (5) with a clearance fit, and the right side of the outer spring (3) is fixedly connected to the left end face of the right support (16); the cylinder (5), the left baffle (8) and the right baffle (12) are all made of non-magnetic materials, and the winding frame (11) and the piston sleeve (9) are all made of magnetic materials;A winding groove is machined in the middle of the winding frame (11), and the excitation coil (10) is wound in the winding groove of the winding frame (11). A lead wire groove is machined on the winding frame (11), a lead wire hole is machined on the right baffle (12), and lead wire holes are machined on the right end cover (15) and the right support (16). The wire of the excitation coil (10) is led out through the lead wire groove of the winding frame (11), the lead wire hole of the right baffle (12), the lead wire hole of the right end cover (15), and the lead wire hole of the right support (16).

[0007] Compared with the prior art, the advantages of this utility model are:

[0008] (1) The piston head assembly of the damper adopts a valve-type structure, forming an annular fluid flow channel between the winding frame and the piston sleeve, and the piston head assembly maintains a tight clearance fit with the inner wall of the cylinder. This structure effectively ensures the coaxiality of the piston rod during reciprocating motion while realizing continuously variable output damping force, thereby significantly improving the working stability of the damper.

[0009] (2) The piston head assembly and piston rod of the damper are fitted with a clearance, allowing relative sliding between them. An inner spring is connected to each end of the piston head assembly, and an outer spring is fitted onto the outside of the damper cylinder. The outer and inner springs are set with different stiffness coefficients and are connected in parallel. By adjusting the input current, the stiffness and damping can be continuously adjusted to meet the vibration reduction requirements over a wide frequency range. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model.

[0011] Figure 2 This is a schematic diagram of the fluid flow channel of this utility model.

[0012] Figure 3 This is a schematic diagram of the magnetic field lines distribution of the excitation coil of this utility model.

[0013] Figure 4 This is a schematic diagram of the left baffle structure of this utility model. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0015] like Figure 1 As shown, this utility model includes: a left support (1), a piston rod I (2), an outer spring (3), a left end cover (4), a cylinder (5), a piston rod II (6), an inner spring I (7), a left baffle (8), a piston sleeve (9), an excitation coil (10), a winding frame (11), a right baffle (12), an inner spring II (13), a piston rod III (14), a right end cover (15), and a right support (16).

[0016] like Figure 2 The diagram shows the flow channel of this utility model. The waist-shaped hole of the left baffle (8), the annular flow channel between the piston sleeve (9) and the winding frame (11), and the waist-shaped hole of the right baffle (12) constitute the flow channel of the damper.

[0017] like Figure 3 The diagram shows the magnetic field distribution of the excitation coil of this invention. The cylinder (5), left baffle (8), and right baffle (12) are all made of non-magnetic materials, while the winding frame (11) and piston sleeve (9) are made of magnetic materials. The magnetic field generated by the excitation coil (8) due to electromagnetic effect passes through the winding frame (11), the annular fluid flow channel, and the piston sleeve (9) in sequence to form a closed loop.

[0018] like Figure 4 The diagram shows the structure of the left baffle of this utility model. The left baffle (8) has four waist-shaped through holes evenly machined in the middle. The magnetorheological fluid can enter the fluid flow channel formed by the piston sleeve (9) and the winding frame (11) through the four waist-shaped holes.

[0019] The working principle of this utility model is as follows:

[0020] When subjected to external vibration excitation, a relative displacement will occur between the left support (1) and the right support (16). The left support (1) drives the piston rod assembly, which consists of piston rod I (2), piston rod II (6) and piston rod III (14), to move. The piston rod assembly, in turn, drives the piston head assembly, which consists of left baffle (8), piston sleeve (9), winding frame (11) and right baffle (12), to reciprocate within the cylinder (5). The magnetorheological fluid is squeezed by the piston head assembly and flows back and forth between the left and right chambers of the cylinder (5) through the fluid flow channel. When current is applied to the excitation coil (10), the magnetic lines of force generated by the electromagnetic effect pass through and are perpendicular to the entire fluid flow channel. Under the action of the magnetic field, the magnetorheological fluid flowing through the fluid flow channel will undergo a magnetorheological effect. The viscosity of the magnetorheological fluid increases with the increase of the magnetic induction intensity, thereby generating a controllable damping force. In addition, inner spring I (7) and inner spring II (13) are fixed to both ends of the piston head assembly, and an outer spring (3) is fitted on the outside of the cylinder (5). The outer spring (3) and inner spring I (7) and inner spring II (13) are set with different stiffness coefficients and are connected in parallel. The relative displacement between the left support (1) and the right support (16) will cause the outer spring (3) to undergo elastic deformation. When there is no current input to the excitation coil (10), there is no relative displacement between the piston head assembly and the piston rod assembly, and inner spring I (7) and inner spring II (13) do not undergo elastic deformation. At this time, the system stiffness is equal to the stiffness of the outer spring (3). When there is no current input to the excitation coil (10), there is relative displacement between the piston head assembly and the piston rod assembly, and inner spring I (7) and inner spring II (13) undergo elastic deformation. At this time, the system stiffness is determined by the outer spring (3), inner spring I (7) and inner spring II (13). The system stiffness increases with the increase of current and is at most the sum of the stiffness of the inner and outer springs. By adjusting the input current, the stiffness and damping can be continuously adjusted to meet the vibration reduction requirements in a wide frequency range.

Claims

1. A magnetorheological damper with simultaneously variable stiffness and damping, characterized in that... include: The left support (1), piston rod I (2), outer spring (3), left end cover (4), cylinder (5), piston rod II (6), inner spring I (7), left baffle (8), piston sleeve (9), excitation coil (10), winding frame (11), right baffle (12), inner spring II (13), piston rod III (14), right end cover (15), and right support (16); the left support (1) and piston rod I (2) are fixedly connected by threads; the right side of the left end cover (4) is clearance-fitted with the inner surface of the cylinder (5) and sealed by a sealing ring; the left end cover (4) and cylinder (5) are fixedly connected by screws; a circular through hole is machined in the middle of the left end cover (4), and the piston rod I (2) is clearance-fitted with the inner surface of the circular through hole of the left end cover (4). The piston rod I (2) and piston rod II (6) are fixedly connected by threads; a circular through hole is machined in the middle of the winding frame (11), and the piston rod II (6) is clearance-fitted with the inner surface of the circular through hole of the winding frame (11) and sealed by a sealing ring; the outer surface of the winding frame (11) is clearance-fitted with the inner circumference of the piston sleeve (9); the outer surface of the piston sleeve (9) is clearance-fitted with the inner circumference of the cylinder (5) and sealed by a sealing ring; the right end face of the left baffle (8) is tightly fitted with the left end face of the winding frame (11) and the left end face of the piston sleeve (9); the left baffle (8) and piston sleeve (9) are fixedly connected by screws; the left end face of the winding frame (11) is fixedly connected with the right side of the inner spring I (7), and the inner spring... The inner surface of spring I (7) is clearance-fitted with the outer surface of piston rod II (6), and the left side of inner spring I (7) is fixedly connected to the right end face of piston rod I (2); the left end face of right baffle (12) is tightly fitted with the right end face of winding frame (11) and the right end face of piston sleeve (9); right baffle (12) and piston sleeve (9) are fixedly connected by screws; piston rod II (6) and piston rod III (14) are fixedly connected by threads; the right end face of winding frame (11) is fixedly connected to the left side of inner spring II (13), the inner surface of inner spring II (13) is clearance-fitted with the outer surface of piston rod II (6), and the right side of inner spring II (13) is fixedly connected to the left end face of piston rod III (14); the left side of right end cap (15) is clearance-fitted with the inner circumferential surface of cylinder (5), and is fixedly connected by screws. The sealing ring is used for sealing; the left end face of the right support (16) is tightly fitted with the right end face of the right end cover (15); the right support (16), the right end cover (15) and the cylinder (5) are fixedly connected by screws; the right end cover (15) has a circular through hole in the middle, the piston rod III (14) is clearance-fitted with the inner surface of the circular through hole of the right end cover (15) and sealed by the sealing ring; the right end face of the left support (1) is fixedly connected with the left side of the outer spring (3), the inner surface of the outer spring (3) is clearance-fitted with the outer surface of the cylinder (5), and the right side of the outer spring (3) is fixedly connected with the left end face of the right support (16); the cylinder (5), the left baffle (8) and the right baffle (12) are all made of non-magnetic material, and the winding frame (11) and the piston sleeve (9) are all made of magnetic material;A winding groove is machined in the middle of the winding frame (11), and the excitation coil (10) is wound in the winding groove of the winding frame (11). A lead wire groove is machined on the winding frame (11), a lead wire hole is machined on the right baffle (12), and lead wire holes are machined on the right end cover (15) and the right support (16). The wire of the excitation coil (10) is led out through the lead wire groove of the winding frame (11), the lead wire hole of the right baffle (12), the lead wire hole of the right end cover (15), and the lead wire hole of the right support (16).

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