CN112196926B

CN112196926B - Magnetic liquid damping vibration absorber

Info

Publication number: CN112196926B
Application number: CN202011144756.5A
Authority: CN
Inventors: 李德才; 韩鹏栋; 李倩; 任思杰; 李英松
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2020-10-23
Filing date: 2020-10-23
Publication date: 2021-08-17
Anticipated expiration: 2040-10-23
Also published as: CN112196926A

Abstract

The invention provides a magnetic liquid damping shock absorber, which belongs to the field of mechanical engineering vibration control. The mass has left, middle and right end portions, each of which has a cross-sectional area that increases in a direction away from the middle portion. The first permanent magnet ring is sleeved on the middle portion and used for providing a suspension force for the mass block, the second permanent magnet ring and the third permanent magnet ring are sleeved on the mass block and used for providing a restoring force for the mass block, and the first permanent magnet and the second permanent magnet are arranged on the shell and respectively extend into the containing cavities at the left end and the right end of the mass block and are used for preventing the mass block from deflecting in the displacement process. When vibration occurs outside, extrusion, friction and viscous shearing are generated between the mass block and the magnetic liquid to consume energy, so that the aim of rapid vibration reduction is fulfilled.

Description

Magnetic liquid damping vibration absorber

Technical Field

The invention relates to the field of mechanical engineering vibration control, in particular to a magnetic liquid damping shock absorber.

Background

The magnetic liquid is a novel functional material with fluidity and magnetism, and the unique property of the magnetic liquid enables the magnetic liquid to have extremely wide application in the engineering field. The magnetic liquid damping shock absorber is a passive shock absorber, has high sensitivity to inertial force, and has the advantages of simple structure, small volume, large energy consumption, long service life and the like. Therefore, the magnetic liquid damping vibration absorber is widely applied to the vibration attenuation of long and straight objects (such as solar sailboards, antennas and the like of space stations) of large-scale spacecrafts with low frequency and small amplitude. Meanwhile, the vibration reduction device has wide application prospect on the ground, such as vibration reduction of a large-power antenna with the length of hundreds of meters, vibration reduction of a precision balance and the like. However, the magnetic liquid damping vibration absorber in the prior art still has the problems of unsatisfactory vibration absorption effect, low vibration absorption efficiency, easy inclination of the mass block when the mass block is vibrated, easy collision with the shell wall to cause vibration absorption failure and the like, and restricts the practical production and application of the magnetic liquid damping vibration absorber.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the embodiment of the invention provides a magnetic liquid damping shock absorber which has the advantages of excellent shock absorption effect, difficulty in damage and the like.

The embodiment of the invention provides a magnetic liquid damping vibration absorber, which comprises: the casing is used for limiting a closed cavity, and the wall surface of the closed cavity comprises a peripheral wall surface and a first side wall surface and a second side wall surface which are opposite in a first direction, wherein the peripheral wall surface is positioned between the first side wall surface and the second side wall surface; a mass located within the closed cavity, the mass having a left end, a middle, and a right end, each of the left and right ends having a cross-section that increases in area in a direction away from the middle; the first permanent magnet ring is arranged on the peripheral wall surface and sleeved on the middle part, a first gap is formed between the inner peripheral surface of the first permanent magnet ring and the outer peripheral surface of the middle part, and the magnetizing direction of the first permanent magnet ring is perpendicular to the first direction; each of the second permanent magnet ring and the third permanent magnet ring is arranged on the peripheral wall surface and sleeved on the mass block, the first permanent magnet ring is positioned between the second permanent magnet ring and the third permanent magnet ring in the first direction, a gap is formed between the inner peripheral surfaces of the second permanent magnet ring and the third permanent magnet ring and the peripheral surface of the mass block, the magnetizing directions of the second permanent magnet ring and the third permanent magnet ring are the same as the first direction, the outer edge of the cross section of one part of the left end part is positioned on the outer side of the inner edge of the second permanent magnet ring, and the outer edge of the cross section of one part of the right end part is positioned on the outer side of the inner edge of the third permanent magnet ring; the mass block is provided with a first end face and a second end face which are opposite in the first direction, the first end face is provided with a first accommodating hole, the second end face is provided with a second accommodating hole, at least one part of the first permanent magnet is positioned in the first accommodating hole, a second gap is formed between the first permanent magnet and the wall face of the first accommodating hole, at least one part of the second permanent magnet is positioned in the second accommodating hole, a third gap is formed between the second permanent magnet and the wall face of the second accommodating hole, and the magnetizing directions of the first permanent magnet and the second permanent magnet are perpendicular to the first direction; a first magnetic liquid adsorbed on the first permanent magnet ring, the first magnetic liquid being filled in the first gap; the second magnetic liquid is adsorbed on the second permanent magnetic ring, the second magnetic liquid can be contacted with the left end part, the third magnetic liquid is adsorbed on the third permanent magnetic ring, and the third magnetic liquid can be contacted with the right end part; and the fourth magnetic liquid is adsorbed on the first permanent magnet, the fourth magnetic liquid is filled in the second gap, the fifth magnetic liquid is adsorbed on the second permanent magnet, and the fifth magnetic liquid is filled in the third gap.

The magnetic liquid damping vibration absorber provided by the embodiment of the invention is provided with the mass block comprising the left end part, the middle part and the right end part, the first permanent magnet ring sleeved on the mass block can enable the mass block to be suspended in the shell, the second permanent magnet ring and the third permanent magnet ring sleeved on the mass block can apply restoring force to the mass block when the mass block deviates from a balance position, and meanwhile, the first permanent magnet and the second permanent magnet are matched with the accommodating grooves at the two ends of the mass block, so that the mass block can be prevented from being inclined and deflected to collide with the inner wall of the shell, the mass block or the shell is prevented from being damaged, and the vibration absorption effect is influenced. When the magnetic liquid damping shock absorber provided by the embodiment of the invention is vibrated by the outside, the mass block is used as a damping mass block to carry out rapid damping under the action of the restoring force of the second permanent magnet ring and the third permanent magnet ring, namely, the magnetic liquid damping shock absorber can realize a good damping effect.

Therefore, the magnetic liquid damping shock absorber provided by the embodiment of the invention has the advantages of excellent shock absorption effect, difficulty in damage and the like.

In addition, the magnetic liquid damping vibration absorber according to the invention has the following additional technical features:

in some embodiments, the closed cavity is cylindrical, the middle portion is cylindrical, the left end portion and the right end portion are both truncated cone-shaped, the first direction is the axial direction of the closed cavity, the first permanent magnet ring is magnetized in the radial direction, and the second permanent magnet ring and the third permanent magnet ring are both magnetized in the axial direction.

In some embodiments, the first receiving hole, the second receiving hole, the first permanent magnet, and the second permanent magnet are all cylindrical, and the first permanent magnet and the second permanent magnet are both radially magnetized.

In some embodiments, the taper angle of the left and right end portions is θ, 4 ° ≦ θ < 90 °.

In some embodiments, the outer peripheral surface of the mass is further coated with an elastic pad.

In some embodiments, the magnetic liquid damping shock absorber of the present invention further comprises a first shielding magnetic ring and a second shielding magnetic ring, said first shielding magnetic ring being located between said first permanent magnet ring and said second permanent magnet ring, said second shielding magnetic ring being located between said first permanent magnet ring and said third permanent magnet ring.

In some embodiments, inner diameters of the first, second, and third permanent magnet rings are equal to each other.

In some embodiments, the magnetic liquid damping vibration absorber of the present invention further includes a first washer provided on the first side wall surface and a second washer provided on the second side wall surface, the first washer being opposed to the first end surface of the mass in the first direction, the second washer being opposed to the second end surface of the mass in the first direction.

In some embodiments, the mass is a non-magnetically conductive material, optionally the mass is an aluminum material.

In some embodiments, the first permanent magnet rings include two, the two first permanent magnet rings are arranged in the first direction, and the two first permanent magnet rings are connected.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

FIG. 1 is a cross-sectional schematic view of a magnetic liquid damping shock absorber in accordance with one embodiment of the present invention.

Fig. 2 is a schematic three-dimensional structure of the mass block in fig. 1.

FIG. 3 is a cross-sectional schematic view of a magnetic liquid damping shock absorber in accordance with another embodiment of the present invention.

Reference numerals:

magnetic liquid damping shock absorber 100;

a housing 1; a body 11; a first end cap 12; a first sidewall surface 121; a second end cap 13; a second sidewall surface 131; a mass block 2; a left end portion 21; a middle portion 22; a right end portion 23; the first accommodation hole 24; the second accommodation hole 25; an elastic pad 26; a first permanent magnet ring 3; a second permanent magnet ring 4; a third permanent magnet ring 5; a first permanent magnet 6; a second permanent magnet 7; the first magnetic liquid 81; a second magnetic liquid 82; a third magnetic liquid 83; a fourth magnetic liquid 84; a fifth magnetic liquid 85; a first shielding magnetic ring 91; a second shielding magnetic ring 92; a first gasket 101; a second gasket 102.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

A magnetic liquid damping shock absorber 100 according to an embodiment of the present invention is described below with reference to fig. 1 to 3.

As shown in fig. 1, a magnetic liquid damping shock absorber 100 according to an embodiment of the present invention includes a case 1, a mass 2, a first permanent magnet ring 3, a second permanent magnet ring 4, a third permanent magnet ring 5, a first permanent magnet 6, and a second permanent magnet 7.

The housing 1 defines a closed cavity, and the walls of the closed cavity include a peripheral wall surface, a first side wall surface 121 and a second side wall surface 131, the first side wall surface 121 and the second side wall surface 131 are opposite in the first direction, and the peripheral wall surface is located between the first side wall surface 121 and the second side wall surface 131. For convenience of description, the direction indicated by the arrow a in fig. 1 is hereinafter referred to as the first direction, i.e., the left-right direction.

The mass 2 is located within the closed cavity. The mass 2 has a left end 21, a middle 22 and a right end 23, the middle 22 being located between the left end 21 and the right end 23 in the first direction. I.e. the left end portion 21 is located to the left of the central portion 22 and the right end portion 23 is located to the right of the central portion 22. The area of the cross section of each of the left and

right end portions

21 and 23 increases in a direction away from the middle portion 22. In other words, the area of the cross section of each of the left and

right end portions

21 and 23 decreases in a direction closer to the middle portion 22.

The area of the cross section herein means the area of a figure surrounded by the outer edges of the cross section of the left end portion 21 (right end portion 23). For example, when the outer edge of the cross section of the left end portion 21 (right end portion 23) is a circle, the area of the cross section of the left end portion 21 (right end portion 23) is the area of the circle. For another example, when the outer edge of the cross section of the left end portion 21 (right end portion 23) is a square, the area of the cross section of the left end portion 21 (right end portion 23) is the area of the square.

The first permanent magnet ring 3 is arranged on the peripheral wall surface of the shell 1, the first permanent magnet ring 3 is sleeved on the middle part 22, and a first gap is formed between the inner peripheral surface of the first permanent magnet ring 3 and the outer peripheral surface of the middle part 22. The magnetizing direction of the first permanent magnet ring 3 is perpendicular to the first direction. That is, the two poles of the first permanent magnet ring 3 are located on the inner circumferential surface and the outer circumferential surface thereof, respectively.

Each of the second permanent magnet ring 4 and the third permanent magnet 5 is provided on the circumferential wall surface of the housing 1, and each of the second permanent magnet ring 4 and the third permanent magnet 5 is fitted over the mass block 2. The first permanent magnet ring 3 is located between the second permanent magnet ring 4 and the third permanent magnet 5 in the first direction. For example, the second permanent magnet ring 4 is located on the left side of the first permanent magnet ring 3, and the third permanent magnet 5 is located on the right side of the first permanent magnet ring 3. Gaps are reserved between the inner peripheral surfaces of the second permanent magnet ring 4 and the third permanent magnet 5 and the outer peripheral surface of the mass block 2. The magnetizing directions of the second permanent magnet ring 4 and the third permanent magnet 5 are the same as the first direction. That is, the two poles of the second permanent magnet ring 4 (third permanent magnet 5) are located on the left and right end faces thereof, respectively.

The outer edge of a part of the cross section of the left end part 21 is positioned outside the inner edge of the second permanent magnet ring 4, and the outer edge of a part of the cross section of the right end part 23 is positioned outside the inner edge of the third permanent magnet ring 5. That is, each of the second permanent magnet ring 4 and the third permanent magnet 5 is sleeved on the mass block 2, but due to size limitation, the left end portion 21 cannot completely penetrate through the second permanent magnet ring 4 from left to right, and the right end portion 23 cannot completely penetrate through the second permanent magnet ring 4 from right to left. Namely, a part of the left end part 21 is always positioned at the left of the second permanent magnet ring 4 due to the size limitation, and a part of the right end part 23 is always positioned at the right of the third permanent magnet ring 5 due to the size limitation.

The first permanent magnet 6 is disposed on the first side wall surface 121 of the case 1, and the second permanent magnet 7 is disposed on the second side wall surface 131 of the case 1. The mass 2 has first and second end faces opposed in the first direction. A first receiving hole 24 is provided at the first end face and a second receiving hole 25 is provided at the second end face. At least a portion of the first permanent magnet 6 is located in the first accommodation hole 24. A second gap is provided between the first permanent magnet 6 and the wall surface of the first accommodation hole 24. At least a portion of the second permanent magnet 7 is located in the second accommodation hole 25. A third gap is provided between the second permanent magnet 7 and the wall surface of the second accommodation hole 25. The magnetizing directions of the first permanent magnet 6 and the second permanent magnet 7 are perpendicular to the first direction, that is, the magnetizing directions of the first permanent magnet 6 and the second permanent magnet 7 are the same as the magnetizing direction of the first permanent magnet ring 3.

As shown in fig. 1, the magnetic liquid damping shock absorber 100 according to the embodiment of the present invention further includes a first magnetic liquid 81, a second magnetic liquid 82, a third magnetic liquid 83, a fourth magnetic liquid 84, and a fifth magnetic liquid 85.

The first magnetic liquid 81 is adsorbed on the first permanent magnet ring 3, and the first magnetic liquid 81 is filled in the first gap. The second magnetic liquid 82 is adsorbed on the second permanent magnet ring 4, and the second magnetic liquid 82 can contact the left end portion 21. The second magnetic liquid 82 being able to contact the left end portion 21 means: when the mass is in the equilibrium position, the second magnetic liquid 82 may or may not be in contact with the left end portion 21; when the mass moves rightward to perform vibration damping, the second magnetic liquid 82 comes into contact with the left end portion 21.

The third magnetic liquid 83 is adsorbed on the third permanent magnet ring 5, and the third magnetic liquid 83 can contact the right end portion 23. The third magnetic liquid 83 is contactable with the right end portion 23, which means that the third magnetic liquid 83 may be in contact with the right end portion 23 or may not be in contact with the right end portion 23. The fourth magnetic liquid 84 is adsorbed on the first permanent magnet 6, the fourth magnetic liquid 84 is filled in the second gap, the fifth magnetic liquid 85 is adsorbed on the second permanent magnet 7, and the fifth magnetic liquid 85 is filled in the third gap.

Under the action of the first permanent magnet ring 3, the second permanent magnet ring 4, the third permanent magnet ring 5, the first permanent magnet 6, the second permanent magnet 7, the first magnetic liquid 81, the second magnetic liquid 82, the third magnetic liquid 83, the fourth magnetic liquid 84 and the fifth magnetic liquid 85, the mass block 2 can be suspended in the closed cavity of the shell 1 and always receives a force towards the equilibrium position of the mass block. That is, when the magnetic fluid damper 100 is not disturbed, the mass 2 and the housing 1 are in a relatively static state, and the mass 2 is in an equilibrium position, and once the mass 2 deviates from the equilibrium position, the mass 2 will be subjected to a force to return to the equilibrium position.

Specifically, the first permanent magnet ring 3 can apply a supporting force to the mass 2 toward the center of the first permanent magnet ring 3 by the first magnetic liquid 81, the supporting force enables the mass 2 to float in the closed cavity, and the supporting force can be referred to as a levitation force, and the direction of the levitation force is perpendicular to the first direction. The second permanent magnet ring 4 is capable of applying a force in the first direction (i.e., the left-right direction) to the mass block 2 toward the first permanent magnet ring 3 by the second magnetic liquid 82. I.e. the second permanent magnet ring 4 can exert a force to the right on the mass 2. The third permanent magnet ring 5 is capable of applying a force in the first direction (i.e., the left-right direction) to the mass block 2 toward the first permanent magnet ring 3 by the third magnetic liquid 83. I.e. the third permanent magnet ring 5 can exert a force to the mass 2 to the left. Such left and right forces applied to the mass 2 cause the mass 2 to be subjected to a force in the left-right direction that returns it to the equilibrium position, which may be referred to as a restoring force.

In addition, the first permanent magnet 6 and the second permanent magnet 7 can apply a supporting force to the mass block 2 towards the balance position thereof through the fourth magnetic liquid 84 and the fifth magnetic liquid 85, so that the mass block 2 is prevented from deflecting, and a certain levitation force can be given to the mass block 2. For example, the first permanent magnet 6 applies a supporting force in a direction perpendicular to the first direction to the mass 2 through the fourth magnetic liquid 84, and the second permanent magnet 7 applies a supporting force in a direction perpendicular to the first direction to the mass 2 through the fifth magnetic liquid 85. The left end portion 21, the middle portion 22 and the right end portion 23 of the mass 2 are supported by external force, and thus do not tilt during movement.

When the magnetic liquid damping vibration absorber 100 provided by the embodiment of the invention mechanically vibrates a damped object, the mass block 2 displaces in the closed cavity, that is, the mass block 2 and the shell 1 move relatively. Because the first permanent magnet ring 3, the second permanent magnet ring 4 and the third permanent magnet ring 5 are sleeved on the mass block 2, the first permanent magnet 6 and the second permanent magnet 7 are respectively positioned in the accommodating holes at the two ends of the mass block 2, and the displacement of the mass block 2 subjected to limiting in the closed cavity can be regarded as moving left and right along a first direction. In the process, the mass 2 and the first magnetic liquid 81, the second magnetic liquid 82, the third magnetic liquid 83, the fourth magnetic liquid 84 and the fifth magnetic liquid 85, and the inside of each magnetic liquid can generate extrusion, friction and viscous shear to consume energy, so that the vibration damping effect is achieved. After a plurality of relative movements, the mass 2 finally returns to its equilibrium position due to the restoring force that returns it to its equilibrium position, i.e. damping is completed.

In some embodiments, as shown in FIG. 1, the left end portion 21 and the right end portion 23 are symmetrically disposed relative to the central portion 22. The second permanent magnet ring 4 and the third permanent magnet ring 5 are symmetrically arranged relative to the first permanent magnet ring 3. When the mass block 2 is in the balance position, the first permanent magnet 6 and the second permanent magnet 7 are symmetrically arranged relative to the mass block 2, and the first permanent magnet ring 3 is sleeved in the middle of the middle part 22.

As shown in fig. 1, the maximum length of the mass 2 in the first direction is smaller than the minimum length of the closed cavity in the first direction, i.e. the mass 2 can move left and right in the closed cavity in the first direction. When the mass 2 is in the equilibrium position, the mass 2 can move both to the left and to the right, i.e. the mass 2 is suspended in a closed cavity in the housing 1 without being affected by the housing 1.

Optionally, the mass 2 is made of a non-magnetic material, and further optionally, the mass 2 is made of an aluminum material, which can reduce the weight of the mass 2 and improve the vibration damping effect.

In some embodiments, as shown in fig. 1, the closed cavity of the housing 1 has a cylindrical shape, the middle portion 22 has a cylindrical shape, and the left end portion 21 and the right end portion 23 have a circular truncated cone shape. It will be appreciated that the left, middle and

right end portions

21, 22, 23 are coaxial, the axis of the mass 2 being the axis of the middle portion 22. The first direction is now the axial direction of the closed cavity, i.e. the axial direction of the mass 2. Each of the first permanent magnet ring 3, the second permanent magnet ring 4, and the third permanent magnet ring 5 is a circular ring-shaped structure and has an inner diameter greater than an outer diameter of the middle portion 22. Alternatively, the inner diameters of the first permanent magnet ring 3, the second permanent magnet ring 4 and the third permanent magnet ring 5 are equal to each other.

It is understood that, in other embodiments, the structures of the closed cavity of the shell 1, the mass block 2, the first permanent magnet ring 3, the second permanent magnet ring 4 and the third permanent magnet ring 5 may be other suitable shapes that cooperate with each other, and will not be described herein again.

Alternatively, as shown in FIG. 1, the taper angles of the left and

right end portions

21 and 23 are θ, 4 ° ≦ θ < 90 °. The taper angle θ means an angle between a generatrix of the truncated cone-shaped left end portion 21 (right end portion 23) and the axis.

In the above embodiment, the first permanent magnet ring 3 is magnetized radially, and the second permanent magnet ring 4 and the third permanent magnet ring 5 are magnetized axially.

As an example, as shown in fig. 1, there are two first permanent magnet rings 3, two first permanent magnet rings 3 are arranged and connected in a first direction, and the magnetizing direction and the magnetic pole position of the two first permanent magnet rings 3 are the same. For example, the N poles of the two first permanent magnet rings 3 are located on the outer circumferential surfaces thereof, and the S poles are located on the inner circumferential surfaces thereof. Optionally, in other embodiments, there are at least three first permanent magnet rings 3.

In some embodiments, as shown in fig. 1 and 3, each of the first accommodation hole 24, the second accommodation hole 25, the first permanent magnet 6, and the second permanent magnet 7 is cylindrical. The diameter of the first permanent magnet 6 is smaller than that of the first accommodation hole 24, and the diameter of the second permanent magnet 7 is smaller than that of the second accommodation hole 25. That is, the first permanent magnet 6 is movable in the first direction relative to the first accommodation hole 24, and the second permanent magnet 7 is movable in the first direction relative to the second accommodation hole 25. The first permanent magnet 6 and the second permanent magnet 7 are both radially magnetized.

Optionally, the first receiving hole 24, the second receiving hole 25, the first permanent magnet 6 and the second permanent magnet 7 are coaxial. Further optionally, the first receiving hole 24, the second receiving hole 25, the first permanent magnet 6, and the second permanent magnet 7 are coaxial with the mass 2.

As an example, as shown in fig. 1, the first and second receiving holes 24 and 25 penetrate in the first direction, that is, the first and second receiving holes 24 and 25 form a central through hole penetrating the mass 2 in the first direction on the mass 2. Optionally, the central axis of the central through hole coincides with the central axis of the mass 2. The design can further reduce the weight of the mass block 2 and improve the vibration reduction effect.

As an example, as shown in fig. 3, the first accommodation hole 24 and the second accommodation hole 25 do not penetrate in the first direction.

It will be appreciated that in other embodiments, the first receiving hole 24, the second receiving hole 25, the first permanent magnet 6 and the second permanent magnet 7 may also be other suitable shapes that fit into each other.

In some embodiments, as shown in fig. 1, the outer peripheral surface of the mass 2 is further coated with an elastic pad 26. The elastic pad 26 is used for preventing the mass block 2 or the shell 1 from being damaged and affecting the vibration damping effect due to the rigid impact generated between the mass block 2 and the inner wall of the shell 1, and meanwhile, the elastic pad 26 can play a certain role in buffering and absorbing vibration. Optionally, the thickness of the resilient pad 26 is 2-3 mm.

In some embodiments, as shown in fig. 1, the magnetic fluid damping shock absorber 100 according to the embodiment of the present invention further includes a first shielding magnetic ring 91 and a second shielding magnetic ring 92, where the first shielding magnetic ring 91 is located between the first permanent magnet ring 3 and the second permanent magnet ring 4, and the second shielding magnetic ring 92 is located between the first permanent magnet ring 3 and the third permanent magnet ring 5. The first shielding magnetic ring 91 and the second shielding magnetic ring 92 are used for preventing the first permanent magnetic ring 3 from magnetic flux leakage and avoiding the interference of other magnetic fields.

Alternatively, the inner diameters of the first, second, third, and first permanent magnet rings 91, 92, 4, 5, and 3 are equal to each other.

In some embodiments, as shown in FIG. 1, magnetic liquid damping shock absorber 100 provided by embodiments of the present invention further comprises a first washer 101 and a second washer 102. The first gasket 101 is provided on the first side wall surface 121 of the case 1, and the second gasket 102 is provided on the second side wall surface 131 of the case 1. The first gasket 101 is opposed to the first end face of the mass 2 in the first direction, and the second gasket 102 is opposed to the second end face of the mass 2 in the first direction. The first washer 101 serves to prevent the first side wall surface 121 of the housing 1 from being rigidly collided with when the mass 2 moves leftward to affect the vibration damping effect. The second gasket 102 is used to prevent the second side wall 131 of the housing 1 from rigidly colliding with the mass 2 when moving rightward, thereby affecting the vibration damping effect. Meanwhile, the first gasket 101 and the second gasket 102 can also play a certain role in buffering and absorbing vibration.

In some embodiments, as shown in fig. 1, the housing 1 includes a body 11, a first end cap 12, and a second end cap 13. The body 11 has a first opening and a second opening which are opposite in the first direction, a first end cap 12 covers the first opening and is connected to the body 11, and a second end cap 13 covers the second opening and is connected to the body 12. The body 11, the first end cap 12 and the second end cap 13 cooperate to form a closed cavity. Wherein the peripheral wall surface of the closed cavity refers to the inner surface of the body 11, the first side wall surface 121 of the closed cavity refers to the right surface of the first end cap 12, and the second side wall surface 131 of the closed cavity refers to the left surface of the second end cap 13.

In the above embodiment, as shown in fig. 1, the first permanent magnet 6 is mounted on the inner wall surface of the first end cap 12, and the second permanent magnet 7 is mounted on the inner wall surface of the second end cap 13. Optionally, the mounting means is adhesive or welding. Each of the first permanent magnet ring 3, the second permanent magnet ring 4, the third permanent magnet ring 5, the first shielding magnetic ring 91, and the second shielding magnetic ring 92 is mounted on the inner wall surface of the body 11. Optionally, the mounting means is adhesive or welding.

By way of example, the first end cap 12 and the second end cap 13 are symmetrical with respect to the body 11. Alternatively, the first end cap 12 and the second end cap 13 are connected to the body 11 by a screw connection.

As an example, as shown in fig. 1, a first permanent magnet ring 3, a second permanent magnet ring 4, a third permanent magnet ring 5, a first shielding magnet ring 91, and a second shielding magnet ring 92 are installed at the middle of the body 11.

Optionally, in some embodiments, in order to improve the sealing performance of the housing 1, a first sealing ring is disposed at a junction of the first end cap 12 and the body 11, and a second sealing ring is disposed at a junction of the second end cap 13 and the body 11.

In some embodiments, as shown in fig. 1, for ease of installation, the mass 2 is symmetrically divided into a first portion including the left end portion 21 and a part of the middle portion 22 connected to the left end portion 21, and a second portion including the right end portion 23 and another part of the middle portion 22 connected to the right end portion 23. The first part and the second part are attached to each other during installation, optionally by means of an adhesive connection.

The structure and the damping process of the magnetic liquid damping shock absorber 100 in this embodiment will be specifically described below by taking the magnetic liquid damping shock absorber 100 shown in fig. 1 and 2 as an example.

The magnetic liquid damping vibration absorber 100 includes a housing 1, a mass block 2, two first permanent magnet rings 3, a second permanent magnet ring 4, a third permanent magnet ring 5, a first shielding magnetic ring 91, a second shielding magnetic ring 92, a first permanent magnet 6, and a second permanent magnet 7. The housing 1 comprises a body 11, a first end cap 12 and a second end cap 13, the body 11, the first end cap 12 and the second end cap 13 defining a cylindrical closed cavity. The mass block 2 comprises a cylindrical middle part 22, a truncated cone-shaped left end part 21 and a truncated cone-shaped right end part 23, wherein the left end part 21 is connected with the left end of the middle part 22, and the right end part 23 is connected with the right end of the middle part 22. The mass 2 is coaxial with the closed cavity. An elastic pad 26 is provided on the outer peripheral surface of the mass 2.

The middle of the inner wall surface of the body 11 has a boss extending axially toward the closed cavity. The two first permanent magnet rings 3, the second permanent magnet ring 4, the third permanent magnet ring 5, the first shielding magnet ring 91 and the second shielding magnet ring 92 have the same inner diameter and outer diameter. And the second permanent magnet ring 4, the first shielding magnet ring 91, the two first permanent magnet rings 3, the second shielding magnet ring 92 and the third permanent magnet ring 5 are connected in sequence from the left and right direction and are installed on the boss. The two first permanent magnet rings 3, the second permanent magnet ring 4, the third permanent magnet ring 5, the first shielding magnetic ring 91 and the second shielding magnetic ring 92 are all sleeved on the mass block 2, and the inner diameter of the first shielding magnetic ring is larger than the outer diameter of the middle part 22. The mass 2 in the equilibrium position has a gap with the second permanent magnet ring 4 and the third permanent magnet ring 5. The two first permanent magnet rings 3 are magnetized in the radial direction, and the second permanent magnet ring 4 and the third permanent magnet ring 5 are magnetized in the axial direction.

As shown in fig. 1, the middle portion of the inner side of the first end cap 12 has a boss, and the middle portion of the inner side of the second end cap 13 also has a boss, and the bosses are opposite to each other in the first direction. The first permanent magnet 6 is arranged on a boss on the inner side of the first end cover 12, and the second permanent magnet 7 is arranged on a boss on the inner side of the second end cover 13. The first permanent magnet 6 and the second permanent magnet 7 are both cylindrical and are both radially magnetized. The mass 2 also has a central through hole extending through the mass 2 along the central axis. A portion of the first permanent magnet 6 and a portion of the second permanent magnet 7 extend into the central through hole. A boss on the inner side of the first end cover 12 is further provided with a first gasket 101, the first gasket 101 is sleeved on the first permanent magnet 6, a boss on the inner side of the second end cover 13 is further provided with a second gasket 102, and the second gasket 102 is sleeved on the second permanent magnet 7. The left end face of the mass 2 is spaced from the first washer 101 and the right end face of the mass 2 in the equilibrium position is spaced from the second washer 102.

The first magnetic liquid 81 is adsorbed on the two first permanent magnet rings 3 and filled in a gap between the inner wall surfaces of the two first magnetic liquids 81 and the outer wall surface of the middle portion 22. The second magnetic liquid 82 is adsorbed on the second permanent magnet ring 4, and the second magnetic liquid 82 can contact the left end portion 21. The third magnetic liquid 83 is adsorbed on the third permanent magnet ring 5, and the third magnetic liquid 83 can contact the right end portion 23. The fourth magnetic liquid 84 is adsorbed on the first permanent magnet 6, and the fourth magnetic liquid 84 is filled in the gap between the first permanent magnet 6 and the inner wall surface of the central through hole. The fifth magnetic liquid 85 is adsorbed on the second permanent magnet 7, and the fifth magnetic liquid 85 is filled in the gap between the second permanent magnet 7 and the inner wall surface of the central through hole. The mass 2 is suspended in the closed cavity and can move left and right in a first direction.

When the magnetic liquid damping vibration absorber 100 provided by the present embodiment mechanically vibrates on the object to be damped, the mass block 2 is displaced in the closed cavity, that is, the mass block 2 and the housing 1 are relatively moved. For example, when the mass 2 moves leftward relative to the housing 1, the intermediate portion 22 undergoes friction and viscous shear with the first magnetic liquid 81. Meanwhile, the distance between the outer peripheral surface of the right end portion 23 and the third permanent magnet ring 5 is gradually reduced, the third magnetic liquid 83 is squeezed, and friction and viscous shear occur between the right end portion 23 and the third magnetic liquid 83. The first permanent magnet 6 and the second permanent magnet 7 respectively make relative movement with the first end and the second end of the central through hole, and friction and viscous shearing occur between the side wall surface of the central through hole and the fourth magnetic liquid 84 and the fifth magnetic liquid 85. At this time, since the third permanent magnet ring 5 applies a rightward restoring force to the right end portion 23 through the third magnetic liquid 83, the mass 2 moves rightward after being displaced leftward by a certain distance. After moving a distance to the right, the mass 2 will move to the left again under the force to the left applied to the left end 21 by the second permanent magnet ring 4. After a plurality of relative movements, the mass 2 finally returns to its equilibrium position, i.e. damping is completed.

The connection relationship between the parts of magnetic liquid damping shock absorber 100 shown in FIG. 1 is as follows:

the two first permanent magnet rings 3, the second permanent magnet ring 4, the third permanent magnet ring 5, the first shielding magnetic ring 91 and the second shielding magnetic ring 92 are connected into a whole in an adhesive manner, and the whole is fixedly connected to a boss on the inner side of the body 11. Then, certain amounts of the first magnetic liquid 81, the second magnetic liquid 82 and the third magnetic liquid 83 are respectively injected on the first permanent magnet ring 3, the second permanent magnet ring 4 and the third permanent magnet ring 5.

The first part and the second part of the mass block 2 are respectively wrapped by the elastic pads 26, and then the first part and the second part of the mass block 2 are fixedly connected into a whole from the inside of the body 11.

The first permanent magnet 6 and the first washer 101 are fixedly connected to the boss on the inner side of the first end cover 12, and the second permanent magnet 7 and the second washer 102 are fixedly connected to the boss on the inner side of the second end cover 13. Then, a certain amount of the fourth magnetic liquid 84 and the fifth magnetic liquid 85 are injected onto the first permanent magnet 6 and the second permanent magnet 7, respectively. The first end cap 12 and the second end cap 13 are fixedly connected with the body 11.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A magnetic liquid damping shock absorber characterized by comprising:

the casing is used for limiting a closed cavity, and the wall surface of the closed cavity comprises a peripheral wall surface and a first side wall surface and a second side wall surface which are opposite in a first direction, wherein the peripheral wall surface is positioned between the first side wall surface and the second side wall surface;

a mass located within the closed cavity, the mass having a left end, a middle, and a right end, each of the left and right ends having a cross-section that increases in area in a direction away from the middle;

the first permanent magnet ring is arranged on the peripheral wall surface and sleeved on the middle part, a first gap is formed between the inner peripheral surface of the first permanent magnet ring and the outer peripheral surface of the middle part, and the magnetizing direction of the first permanent magnet ring is perpendicular to the first direction;

each of the second permanent magnet ring and the third permanent magnet ring is arranged on the peripheral wall surface and sleeved on the mass block, the first permanent magnet ring is positioned between the second permanent magnet ring and the third permanent magnet ring in the first direction, a gap is formed between the inner peripheral surfaces of the second permanent magnet ring and the third permanent magnet ring and the peripheral surface of the mass block, the magnetizing directions of the second permanent magnet ring and the third permanent magnet ring are the same as the first direction, the outer edge of the cross section of one part of the left end part is positioned on the outer side of the inner edge of the second permanent magnet ring, and the outer edge of the cross section of one part of the right end part is positioned on the outer side of the inner edge of the third permanent magnet ring;

the mass block is provided with a first end face and a second end face which are opposite in the first direction, the first end face is provided with a first accommodating hole, the second end face is provided with a second accommodating hole, at least one part of the first permanent magnet is positioned in the first accommodating hole, a second gap is formed between the first permanent magnet and the wall face of the first accommodating hole, at least one part of the second permanent magnet is positioned in the second accommodating hole, a third gap is formed between the second permanent magnet and the wall face of the second accommodating hole, and the magnetizing directions of the first permanent magnet and the second permanent magnet are perpendicular to the first direction;

a first magnetic liquid adsorbed on the first permanent magnet ring, the first magnetic liquid being filled in the first gap;

the second magnetic liquid is adsorbed on the second permanent magnetic ring, the second magnetic liquid can be contacted with the left end part, the third magnetic liquid is adsorbed on the third permanent magnetic ring, and the third magnetic liquid can be contacted with the right end part; and

fourth magnetic liquid and fifth magnetic liquid, fourth magnetic liquid adsorbs on the first permanent magnet, fourth magnetic liquid fills in the second clearance, fifth magnetic liquid adsorbs on the second permanent magnet, fifth magnetic liquid fills in the third clearance.

2. The magnetic liquid damping shock absorber as set forth in claim 1 wherein said enclosed cavity is cylindrical, said middle portion is cylindrical, said left end portion and said right end portion are each frustoconical, said first direction is axial of said enclosed cavity, said first permanent magnet ring is radially magnetized, and said second permanent magnet ring and said third permanent magnet ring are both axially magnetized.

3. The magnetic liquid damping shock absorber of claim 2, wherein the first receiving hole, the second receiving hole, the first permanent magnet, and the second permanent magnet are all cylindrical, and the first permanent magnet and the second permanent magnet are both radially magnetized.

4. The magnetic liquid damping shock absorber according to claim 2 wherein the taper angle of said left end portion and said right end portion is θ, 4 ° ≦ θ < 90 °.

5. The magnetic liquid damping shock absorber as claimed in claim 1, wherein the outer peripheral surface of said mass is further coated with an elastic pad.

6. The magnetic liquid damping shock absorber as recited in claim 1 further comprising a first shielding magnetic ring and a second shielding magnetic ring, said first shielding magnetic ring being located between said first permanent magnet ring and said second permanent magnet ring, said second shielding magnetic ring being located between said first permanent magnet ring and said third permanent magnet ring.

7. The magnetic liquid damping shock absorber as recited in claim 6 wherein inner diameters of said first shielding magnetic ring, said second shielding magnetic ring, said first permanent magnet ring, said second permanent magnet ring and said third permanent magnet ring are equal to each other.

8. The magnetic liquid damping shock absorber according to claim 1, further comprising a first washer provided on said first side wall surface and a second washer provided on said second side wall surface, said first washer being opposed to said first end surface of said mass in said first direction, said second washer being opposed to said second end surface of said mass in said first direction.

9. The magnetic liquid damping shock absorber as claimed in claim 1 wherein said mass is a non-magnetically conductive material and said mass is an aluminum material.

10. The magnetic liquid damping shock absorber according to claim 1, wherein said first permanent magnet rings comprise two, said two first permanent magnet rings being arranged in a first direction, said two first permanent magnet rings being connected.