Multi-damping-channel magnetorheological damper

Abstract

The multi-damping-channel magnetorheological damper comprises a cylinder barrel with the two ends open, the two sides of the cylinder barrel are in threaded connection with a left end cover and a right end cover correspondingly, and a piston shaft is arranged in the cylinder barrel; a damping sleeve is arranged on a shaft body of the piston shaft, an inner barrel is arranged on the side, close to the cylinder barrel, of the left end cover, the piston shaft is located in the inner barrel, the inner barrel is located in the damping sleeve, gaps are formed among the piston shaft, the inner barrel, the damping sleeve and the cylinder barrel respectively, the gaps are communicated to form a damping channel, magnetorheological fluid is injected into the damping channel, and the outer wall of the damping sleeve is sleeved with a magnet exciting coil. A damping channel is formed through gaps formed among the piston shaft, the inner barrel, the damping sleeve and the cylinder barrel, output damping force can change along with displacement of the piston shaft, the left end cover and the right end cover are in threaded connection with the cylinder barrel, the damping force can be further adjusted by adjusting the screw-in distance of threads and extruding magnetorheological fluid, and therefore the damper is simple in structure and convenient to use. And the purpose of being adjustable along with current and displacement can be achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of dampers, and in particular relates to a magnetorheological damper with multiple damping channels. Background Art

[0002] Magnetorheological fluid is a smart material with superior performance. It is mainly composed of three parts: ultrafine metal soft magnetic particles with high magnetic permeability and low magnetic hysteresis, surfactant and base carrier liquid. This smart material has a unique magnetorheological effect, that is, it is in a free-flowing state in the absence of an external magnetic field. Under the action of an external magnetic field, the soft magnetic particles will form a chain structure with shear strength along the direction of the magnetic field, instantly changing from liquid to semi-solid or quasi-solid. Its hardening degree can be continuously adjusted according to the magnetic field intensity. The magnetorheological damper that introduces magnetorheological fluid as the working medium has the characteristics of simple structure, rapid response and excellent damping performance.

[0003] Magnetorheological dampers change the damping output force by increasing the flow channel of the magnetorheological fluid and changing the current of the excitation coil. For example, Chinese invention publication number CN115853949A discloses a double-tube magnetorheological damper with adjustable damping gap, including an outer sleeve, a piston rod, a piston head, a first inner sleeve, a second inner sleeve, an upper end cover and a lower end cover. A first channel is formed between the upper end cover and the first inner sleeve, and a second channel is formed between the lower end cover and the second inner sleeve. Both the first channel and the second channel are bent structures. The damping force is increased by increasing the length of the damping channel.

[0004] Traditionally, increasing the length of the damping channel will make the structure of the magnetorheological damper complicated. When the input current remains unchanged, the damping force cannot be adjusted. It does not have both the functions of adjustable damping with current and adjustable damping with displacement, and ignores the economic cost brought by real-time current control. Therefore, a magnetorheological damper with a simple structure, adjustable damping with current and displacement, and low economic cost was invented. Summary of the Invention

[0005] The purpose of the present invention is to set a piston shaft, an inner tube, a damping sleeve and a cylinder tube, and provide gaps between them to form a damping channel. The output damping force can change with the displacement of the piston shaft, and the left end cover and the right end cover are threadedly connected to the cylinder tube. The damping force can be further adjusted by adjusting the screw-in distance of the thread and squeezing the magnetorheological fluid, so as to solve the problem in the above-mentioned background technology that the structure of the magnetorheological damper becomes complicated in order to increase the length of the damping channel, and the damping force is only adjusted by current.

[0006] The specific technical solutions of the present invention are as follows: A multi-damping channel magnetorheological damper comprises a cylinder with openings at both ends, with a left end cover and a right end cover being threadedly connected on both sides of the cylinder, a piston shaft being provided in the cylinder, and the left and right sides of the piston shaft being connected to the left end cover and the right end cover hole shafts respectively; a damping sleeve being detachably fixedly connected to the shaft body of the piston shaft, an inner cylinder being provided on the side of the left end cover close to the cylinder, the inner cylinder being located in the cylinder, the piston shaft being located in the inner cylinder, the opening of the damping sleeve being directed towards the inner cylinder, the inner cylinder being located in the damping sleeve, gaps being provided between the piston shaft, the inner cylinder, the damping sleeve and the cylinder, several gaps being connected to form a damping channel, the damping channel being filled with magnetorheological fluid, and an excitation coil being provided on the outer wall of the damping sleeve.

[0007] Furthermore, a plurality of excitation coils are provided and are linearly arranged along the central axis of the piston shaft.

[0008] Furthermore, a plurality of placement grooves are provided on the circumference of the outer wall of the damping sleeve. The plurality of placement grooves are linearly arranged along the central axis of the piston shaft, and the excitation coil is located in the placement grooves.

[0009] Furthermore, an annular protrusion is provided on the circumferential direction of the shaft rod of the piston shaft, and the outer diameter of the annular protrusion is smaller than the inner diameter of the inner cylinder.

[0010] Furthermore, the right vertical annular array of the annular protrusion has several bolt mounting holes, and the damping sleeve is provided with several bolt mounting through holes at positions corresponding to the bolt mounting holes. The annular protrusion and the damping sleeve are fixedly connected by fastening bolts and the threaded cooperation of the bolt mounting holes and the bolt mounting through holes. A countersunk groove is provided at the right hole opening of the bolt mounting through hole, and the fastening bolt is a countersunk bolt.

[0011] Furthermore, a permanent magnet is fixedly sleeved on the outer wall of the annular protrusion.

[0012] Furthermore, a groove is provided in the circumferential direction of the outer wall of the annular protrusion, and the permanent magnet is fixed in the groove.

[0013] Furthermore, the left end cover and the right end cover are respectively provided with an axial hole, and a guide sealing assembly is provided in the axial hole.

[0014] Furthermore, the left end cover is provided with a flange connector, and a connecting flange is provided on the side of the cylinder barrel close to the left end cover. The flange connector and the connecting flange are relatively provided with a plurality of assembly holes, and the assembly holes are equipped with bolt assemblies.

[0015] Furthermore, the right end cover is provided with an injection hole, and the magnetorheological fluid is injected into the damping channel through the injection hole.

[0016] Compared with the prior art, the present invention has the following beneficial effects: From the inside to the outside, a piston shaft, an inner tube, a damping sleeve and a cylinder are sequentially arranged with gaps between each other, and all the gaps are connected to form a damping channel. The damping sleeve and the inner tube form a sleeve structure, which increases the length of the damping channel and simplifies the internal structure of the damper. It realizes that the damping force changes with the displacement of the piston shaft in the cylinder when the current remains unchanged. It is suitable for situations where the current cannot be adjusted in real time, reducing economic costs. By adjusting the screw-in distance of the left end cover and the right end cover in the cylinder, the magnetorheological fluid is squeezed and the damping force is further adjusted. When there is no power input, it still has a certain damping output force, which increases the advantages of a wide adjustable damping range and low energy consumption.

[0017] By arranging permanent magnets and several excitation coils and applying magnetic fields of different strengths at different positions in the damping channel, the damping force changes with the current, thereby improving the utilization rate of the damping channel and making the damper respond quickly and highly controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a cross-sectional view of embodiment 1 of the present invention; Figure 2 A cross-sectional view of the damping sleeve in Example 1 of the present invention Reference numerals: 1. Cylinder barrel; 11. Connecting flange; 2. Left end cover; 21. Inner cylinder; 22. Flange connector; 3. Right end cover; 31. Liquid injection hole; 4. Piston shaft; 41. Annular protrusion; 411. Groove; 42. Permanent magnet; 5. Damping sleeve; 51. Excitation coil; 52. Mounting slot; 6. Damping channel; 7. Magnetorheological fluid; 8. Guide seal assembly; 9. Bolt assembly. DETAILED DESCRIPTION

[0019] In order to better understand the purpose, structure and function of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0020] In the description of the present invention, it should be understood that the terms "left", "right", "inside", "outside" and the like indicate directions or positional relationships based on the attached Figure 1 The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as a limitation on the present invention. Example 1

[0021] See Figure 1 and Figure 2 , this embodiment 1 discloses a multi-damping channel magnetorheological damper, including a cylinder 1 with openings at both ends, and a left end cover 2 and a right end cover 3 are respectively threadedly connected on both sides of the cylinder 1. The screwing depth of the left end cover 2 and the right end cover 3 in the cylinder 1 can be adjusted through the threaded connection. Different screwing depths cause the left end cover 2 and the right end cover 3 to apply different pressures to the magnetorheological fluid 7 inside the cylinder 1. The deeper the screwing, the greater the damping force, thereby achieving the adjustment of the damping force without passing current, and the threaded connection facilitates the replacement and maintenance of the left end cover 2 and the right end cover 3. A piston shaft 4 is provided in the cylinder 1, and the left and right sides of the piston shaft 4 are respectively connected to the hole axis of the left end cover 2 and the right end cover 3, and the left and right ends of the piston shaft 4 are respectively located outside the cylinder 1; a damping sleeve 5 is detachably fixedly connected to the shaft body of the piston shaft 4, and the damping sleeve 5 is a cylindrical sleeve with one end open. Structure, the damping sleeve 5 is sleeved on the piston shaft 4, and the other end of the damping sleeve 5 is connected to the hole axis of the piston shaft 4. The left end cover 2 is provided with an inner cylinder 21 near the cylinder 1. The inner cylinder 21 is located in the cylinder 1, and the piston shaft 4 is located in the inner cylinder 21. The opening of the damping sleeve 5 faces the inner cylinder 21 side, and the inner cylinder 21 is located in the damping sleeve 5. There are gaps between the piston shaft 4, the inner cylinder 21, the damping sleeve 5 and the cylinder 1 respectively. Several gaps are connected to form a damping channel 6. The damping channel 6 is filled with magnetorheological fluid 7. The outer wall of the damping sleeve 5 is sleeved with an excitation coil 51. Different currents can be applied to the excitation coil 51 to adjust the magnetic field size. When the piston shaft 4 moves back and forth, the length of the damping channel 6 changes continuously, and the working flow path length of the magnetorheological fluid 7 changes accordingly. There is no need to adjust the current input size, so that the damping output force can change with the displacement.

[0022] There are several excitation coils 51. In this embodiment, there are two excitation coils 51, and both are independently controlled to provide an electromagnetic field. The two excitation coils 51 are linearly arranged along the central axis direction of the piston shaft 4. Increasing the number of excitation coils 51 and independently controlling them can further adjust the adjustable range of the damping force.

[0023] The outer wall of the damping sleeve 5 is provided with a plurality of placement grooves 52 in a circumferential direction. The plurality of placement grooves 52 are linearly arranged along the central axis of the piston shaft 4. The excitation coil 51 is located in the placement grooves 52 and does not block the movement of the magnetorheological fluid 7 in the damping channel 6. In this embodiment, there are two placement grooves 52. Figure 1 , one is close to the middle position of the damping sleeve 5, and the other is located at the right end of the damping sleeve 5. Further optimization is to refer to Figure 2 Since there is a bottom plate at the right end of the damping sleeve 5, which is used to connect with the hole axis of the piston shaft 4, the depth of the placement groove 52 located at the right end of the damping sleeve 5 extends to the bottom plate, which can increase the influence of the excitation coil 51 in the placement groove 52 on the surrounding magnetorheological fluid 7 and improve the effect of the excitation coil 51.

[0024] An annular protrusion 41 is circumferentially provided on the shaft of the piston shaft 4. The outer diameter of the annular protrusion 41 is smaller than the inner diameter of the inner cylinder 21. The annular protrusion 41 is located inside the inner cylinder 21. A gap is provided between the outer wall of the annular protrusion 41 and the inner wall of the inner cylinder 21 to form a damping channel 6.

[0025] The right vertical annular array of the annular protrusion 41 has several bolt mounting holes, and the damping sleeve 5 is provided with several bolt mounting through holes at positions corresponding to the bolt mounting holes. The annular protrusion 41 and the damping sleeve 5 are fixedly connected by fastening bolts and the threaded cooperation of the bolt mounting holes and the bolt mounting through holes. This detachable connection facilitates the maintenance and replacement of the piston shaft 4 and the damping sleeve 5. A countersunk groove is provided at the right side opening of the bolt mounting through hole, and the fastening bolt is a countersunk bolt. Tightening the top of the countersunk bolt into the countersunk groove will not block the movement of the magnetorheological fluid 7 in the damping channel 6.

[0026] A permanent magnet 42 is fixedly mounted on the outer wall of the annular protrusion 41. The permanent magnet 42 provides a permanent magnetic field to ensure that the damper still has a certain output force when there is no power supply.

[0027] A groove 411 is circumferentially provided on the outer wall of the annular protrusion 41 , and the permanent magnet 42 is fixed in the groove 411 and does not block the magnetorheological fluid 7 from moving in the damping channel 6 .

[0028] The left end cover 2 and the right end cover 3 are respectively provided with an axial hole, and a guide sealing assembly 8 is provided in the axial hole. The guide sealing assembly 8 is a mechanical assembly that combines the guiding function and the sealing function. What can be further optimized and limited is that the guide sealing assembly 8 is composed of a guide ring and a sealing ring. The guide ring and the sealing ring are mounted on the shaft of the piston shaft 4 and fixed in the axial hole. The piston shaft 4 is guided and supported by the guide ring, and the radial force is absorbed to ensure the linearity of the reciprocating motion of the piston shaft 4. At the same time, the sealing ring prevents the magnetorheological fluid 7 from leaking or external contaminants such as dust and impurities from entering, thereby improving the sealing tightness of the cylinder 1 and the reliability of the damper system.

[0029] The left end cover 2 is provided with a flange connector 22, and the cylinder barrel 1 is provided with a connecting flange 11 on the side close to the left end cover 2. The flange connector 22 and the connecting flange 11 are provided with several assembly holes relative to each other, and the assembly holes are equipped with bolt assemblies 9. The bolt assembly 9 includes bolts, nuts and gaskets. The bolt assembly 9 improves the stability of the connection between the left end cover 2 and the cylinder barrel 1.

[0030] The right end cover 3 is provided with an injection hole 31 , through which the magnetorheological fluid 7 is injected into the damping channel 6 . A further optimization and limitation is that the injection hole 31 is provided with a plug to prevent the magnetorheological fluid 7 from leaking.

[0031] Working principle: external force acts on the piston shaft 4, and the piston shaft 4 drives the damping sleeve 5 to move together. The permanent magnet 42 generates a permanent magnetic field, which acts on the magnetorheological fluid 7 at the piston shaft 4 to generate a damping force. The input current is provided by several excitation coils 51 to generate an electromagnetic field, which acts on the magnetorheological fluid 7 at the cylinder 1 to generate a damping force; when the piston shaft 4 moves back and forth, the length of the damping channel 6 changes with the displacement. When the input current remains unchanged, the output damping force changes with the displacement; according to the actual working conditions, the current of the excitation coil 51 can be adjusted independently to solidify the magnetorheological fluid 7 at different positions and to different degrees, and adjust the damping force of the damper to change continuously. Through the structure of multiple damping channels 6, the damping force of the damper can be effectively increased, and the application range of the damper can be expanded. At the same time, according to the working conditions of the damper, the distance between the left end cover 2 and the right end cover 3 screwed into the cylinder 1 can be adjusted to further squeeze the magnetorheological fluid 7 to increase the damping force. Example 2

[0032] The damping sleeve 5 can be equipped with multiple layers of sleeves as needed, and the inner diameters of the multiple layers of sleeves gradually increase. The inner cylinder 21 is also correspondingly provided with multiple layers of inner cylinders, and the outer diameters of the multiple layers of inner cylinders gradually increase. Each layer of inner cylinders is staggered with each layer of sleeves, and there are gaps between them. All gaps are the same, further increasing the number of damping channels and improving the control range of the damping force.

[0033] It will be understood that the present invention is described by way of some embodiments, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A multi-damping channel magnetorheological damper, characterized in that: The invention comprises a cylinder (1) with two ends open, a left end cover (2) and a right end cover (3) being respectively threadedly connected on both sides of the cylinder (1), a piston shaft (4) being provided in the cylinder (1), and the left and right sides of the piston shaft (4) being respectively connected to the hole shafts of the left end cover (2) and the right end cover (3); a damping sleeve (5) being detachably fixedly connected to the shaft body of the piston shaft (4), an inner cylinder (21) being provided on the side of the left end cover (2) close to the cylinder (1), and the inner cylinder (21) being located in the cylinder ( 1), the piston shaft (4) is located in the inner tube (21), the opening of the damping sleeve (5) faces one side of the inner tube (21), the inner tube (21) is located in the damping sleeve (5), gaps are respectively provided between the piston shaft (4), the inner tube (21), the damping sleeve (5) and the cylinder (1), several gaps are connected to form a damping channel (6), the damping channel (6) is filled with magnetorheological fluid (7), and the outer wall of the damping sleeve (5) is provided with an excitation coil (51).

2. The multi-damping channel magnetorheological damper according to claim 1, characterized in that: A plurality of excitation coils (51) are provided and are linearly arranged along the central axis of the piston shaft (4).

3. The multi-damping channel magnetorheological damper according to claim 2, characterized in that: A plurality of placement grooves (52) are provided on the outer wall of the damping sleeve (5) in a circumferential direction. The plurality of placement grooves (52) are linearly arranged along the central axis direction of the piston shaft (4). The excitation coil (51) is located in the placement groove (52).

4. The multi-damping channel magnetorheological damper according to claim 1, characterized in that: An annular protrusion (41) is provided circumferentially on the shaft of the piston shaft (4), and the outer diameter of the annular protrusion (41) is smaller than the inner diameter of the inner cylinder (21).

5. The multi-damping channel magnetorheological damper according to claim 4, characterized in that: The right vertical annular array of the annular protrusion (41) has several bolt mounting holes, and the damping sleeve (5) is provided with several bolt mounting through holes at positions corresponding to the bolt mounting holes. The annular protrusion (41) and the damping sleeve (5) are fixedly connected by fastening bolts, the bolt mounting holes and the threaded engagement of the bolt mounting through holes. A countersunk groove is provided at the right opening of the bolt mounting through hole, and the fastening bolt is a countersunk bolt.

6. The multi-damping channel magnetorheological damper according to claim 4, characterized in that: A permanent magnet (42) is fixedly sleeved on the outer wall of the annular protrusion (41).

7. The multi-damping channel magnetorheological damper according to claim 6, characterized in that: A groove (411) is provided in the circumferential direction of the outer wall of the annular protrusion (41), and the permanent magnet (42) is fixed in the groove (411).

8. The multi-damping channel magnetorheological damper according to claim 1, characterized in that: The left end cover (2) and the right end cover (3) are respectively provided with an axial hole, and a guide seal assembly (8) is provided in the axial hole.

9. The multi-damping channel magnetorheological damper according to claim 1, characterized in that: The left end cover (2) is provided with a flange connector (22), and the cylinder barrel (1) is provided with a connecting flange (11) on a side close to the left end cover (2). The flange connector (22) and the connecting flange (11) are provided with a plurality of assembly holes opposite to each other, and the assembly holes are provided with bolt assemblies (9).

10. The multi-damping channel magnetorheological damper according to claim 1, characterized in that: The right end cover (3) is provided with a liquid injection hole (31), and the magnetorheological fluid (7) is injected into the damping channel (6) through the liquid injection hole (31).

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