Rotary magnetorheological damper with hybrid working mode and control method thereof

Abstract

This invention proposes a rotary magnetorheological damper with a hybrid operating mode, comprising a multi-channel stator, a sector block rotor, and a shaft. The multi-channel stator contains channels composed of multiple levels of gaps. The shaft drives the sector block rotor to rotate, causing the gap between the sector block rotor and the multi-channel stator to change, while simultaneously allowing the magnetorheological fluid to flow through the gaps. When the distance between the multi-channel stator and the sector block rotor increases to the point where the main body of the magnetic circuit passes through the multi-channel stator and the large and small arc-shaped magnetic guide blocks, a valve mode is formed at the gap within the multi-channel stator. When the distance between the multi-channel stator and the sector block rotor decreases to the point where the main body of the magnetic circuit also passes through the sector block rotor, a compression mode is formed at the gap between the multi-channel stator and the sector block rotor. This invention has a simple structure and two operating modes, enabling it to provide a larger damping torque in a relatively small volume.

Description

Technical Field

[0001] This invention relates to the field of magnetorheological damper technology, and in particular to a rotary magnetorheological damper with a hybrid operating mode and its control method. Background Technology

[0002] Magnetorheological fluid (MRF) is a novel type of intelligent fluid material. Its main characteristic is the ability to alter fluid properties under the influence of an external magnetic field, exhibiting advantages such as excellent controllability, reversibility, and fast response. A magnetorheological damper is a device that utilizes the properties of magnetorheological fluid to achieve vibration reduction and control. It can adjust the magnitude and direction of the coil current, thereby regulating the strength and direction of the magnetic field, and changing the viscosity of the magnetorheological fluid, thus controlling the damping characteristics of the damper.

[0003] Based on their operating mode and application, magnetorheological dampers can be divided into direct-acting and rotary types. Direct-acting dampers primarily use the reciprocating motion of a piston to drive the flow of magnetorheological fluid; they are generally larger in size, occupying more space in the system structure and are not suitable for rotating systems. Unlike direct-acting dampers, rotary dampers primarily use a shaft to drive a sector-shaped rotor; they are suitable for systems requiring rotational motion, are relatively smaller in size, and can be used in situations with limited structural space. Based on the force conditions and flow characteristics of the magnetorheological fluid, the main operating mode of rotary magnetorheological dampers is shear-type. The principle is that one magnetic pole is fixed, while the other moves perpendicular to the magnetic field. Friction drives the magnetorheological fluid, generating shear force. By adjusting the magnetic field strength, the shear yield strength is changed, thereby altering the damping force. With the continuous development and improvement of magnetorheological fluid technology, rotary magnetorheological dampers have been widely used in aerospace, automotive, and construction fields. They can be used to reduce structural vibration, improve stability, increase system response speed, and suppress impact loads. In addition, rotating magnetorheological dampers can effectively improve the durability and reliability of systems, reduce maintenance costs, and bring important technological breakthroughs to the engineering field.

[0004] The existing design of rotary magnetorheological dampers still has shortcomings, mainly in the following aspects:

[0005] First, currently, the main operating mode of rotary magnetorheological dampers is shear-type, and the main structural types are drum and disc. The rotating shaft drives the rotor to rotate, generating a shear effect on the magnetorheological fluid to produce damping force. However, these types of dampers provide limited damping torque and are only suitable for low-damping conditions, making it difficult to meet the requirements of rotating conditions that require large damping torque.

[0006] Secondly, in order to increase the damping output, some scholars have changed the shape of the contact surface between the rotor and the magnetorheological fluid to change its single shearing working mode. However, the gap between the contact surface between the rotor and the magnetorheological fluid is very small, generally 1~2mm, which makes the manufacturing of the damper difficult and increases the cost. In addition, some scholars have increased the contact area between the rotor and the magnetorheological fluid, but this method has little effect on increasing the damping force and also increases the size of the damper structure, which limits its application in systems with limited space. Summary of the Invention

[0007] To address the problems of existing technologies, this invention proposes a rotary magnetorheological damper with a hybrid operating mode and its control method. It has a simple structure and can provide a larger damping torque in a relatively small volume.

[0008] The present invention adopts the following technical solution.

[0009] A rotary magnetorheological damper with a hybrid operating mode includes a multi-channel stator, a sector block rotor (10), and a rotating shaft (12). The rotating shaft drives the sector block rotor to rotate under the drive of an external load, causing the distance between the multi-channel stator and the sector block rotor to change. The rotation angle of the rotating shaft is detected by an angle sensor and forms a feedback signal sent to the current controller. The outer side of the multi-channel stator is connected to the outer shell (1) through a large arc-shaped magnetic block (3) and fixed to the inner wall of the outer shell. The inner side is tightly attached to the rotating shaft through a small arc-shaped magnetic block (13). The outer side of the sector block rotor (10) is tightly attached to the inner wall of the outer shell, and the inner side is connected to the rotating shaft.

[0010] The multi-channel stator has multiple flow channels formed by gaps, and an excitation coil for generating a magnetic field is wound on the outside; the current of the excitation coil is controlled by a current controller; the outer shell is filled with a magnetorheological fluid (9) whose viscosity can be changed by a magnetic field; the rotating shaft drives the sector block rotor to rotate, so that the magnetorheological fluid flows in the gap.

[0011] When the distance between the multi-channel stator and the sector block rotor increases to the point that the main body of the magnetic circuit passes through the multi-channel stator and the large and small arc-shaped magnetic guide blocks, a valve mode is formed in the gap within the multi-channel stator; that is, the magnetorheological fluid in the gap within the multi-channel stator forms a high-viscosity state under the action of the magnetic field, so as to reduce the flow velocity of the magnetorheological fluid in the gap and thus provide damping force.

[0012] When the distance between the multi-channel stator and the sector block rotor decreases to the point where the main magnetic circuit also passes through the sector block rotor, a squeezing mode is simultaneously formed at the gap between the multi-channel stator and the sector block rotor. Specifically, the magnetic field of the excitation coil changes to increase the viscosity of the magnetorheological fluid, causing the magnetorheological fluid at the gap between the multi-channel stator and the sector block rotor to approach a solidified state. This causes the high-viscosity magnetorheological fluid flowing through the gap between the multi-channel stator and the sector block rotor to be in a squeezing mode, thereby increasing the damping force of the damper.

[0013] The outer casing is connected to the outer casing end cap (14) at both ends, and the outer casing end cap is connected to the bearing end cap (16); a bearing (18) is installed between the bearing end cap and the rotating shaft; the inner side of the sector block rotor is connected to the rotating shaft through a flat key (11).

[0014] The large arc-shaped magnetic conductor, the small arc-shaped magnetic conductor, the multi-channel stator, and the sector-shaped rotor are all arranged in pairs and are symmetrically distributed along the shaft diameter.

[0015] The multi-channel stator includes a coil frame (4), an excitation coil (5), and also includes a number of flow channel baffles with flow holes and a number of gap magnetic blocking plates (7) provided in the coil frame; the flow holes of the flow channel baffles provided in the coil frame are divided into multiple categories according to their distribution or specifications;

[0016] The coil frame has a groove of a preset depth for winding the excitation coil on its outside; the coil frame has a hollow structure inside, and the flow channel baffle and magnetic blocking plate are stacked and installed in the hollow structure inside the coil frame in the order of flow channel baffle (8) with a first type of flow hole, gap magnetic blocking plate, and flow channel baffle (6) with a second type of flow hole, to form a multi-level gap flow channel.

[0017] The flow channel baffle with the first type of flow hole has an arc-shaped flow hole in the middle position; the flow channel baffle with the second type of flow hole has an arc-shaped flow hole in the top position near the outer shell and the bottom position near the rotating shaft; the gap baffle is a rectangular frame with a slightly thicker outer side and a slightly thinner inner side.

[0018] The side of the large arc-shaped magnetic block that contacts the multi-channel stator has a wedge-shaped slot for radial positioning and installation of the multi-channel stator.

[0019] The inner wall of the outer shell that contacts the large arc-shaped magnetic block is provided with a wedge-shaped groove for radial positioning and installation of the large arc-shaped magnetic block; both ends of the outer shell are provided with several threaded holes; both ends of the outer shell are provided with sealing ring grooves for installing sealing rings.

[0020] A fan-shaped groove is provided on the side of the outer casing end cover that connects to the outer casing cylinder for axial positioning and installation of the large arc-shaped magnetic guide block, the small arc-shaped magnetic guide block, and the multi-channel stator; the outer casing end cover has several threaded through holes; a sealing ring groove is provided at the junction of the outer casing end cover and the rotating shaft for installing the sealing ring.

[0021] A double keyway is provided on the shaft segment connecting the rotating shaft and the sector block rotor.

[0022] A control method for a rotary magnetorheological damper with hybrid operating modes, employing the rotary magnetorheological damper with hybrid operating modes described above, is characterized in that: when the damper operates in valve mode, the excitation current of the excitation coil is a preset value.

[0023] When the rotor moves to near its limit position, that is, when the gap angle between the sector block rotor and the multi-channel stator is lower than the threshold, the damper operates in a mixed mode combining valve mode and compression mode. The excitation coil increases the current based on the original excitation current to increase the damping output force and form a larger damping torque, and protect the device.

[0024] Compared with the prior art, the present invention has the following beneficial effects: In order to improve the output torque of the rotary magnetorheological damper, a damper structure with a hybrid working mode is proposed. By designing a multi-stage gap flow channel, the rotor rotation changes the gap between the rotor and the stator, so that the damper has both valve mode and extrusion mode working modes. Compared with the traditional single working mode that relies on shear mode, the output torque is greatly improved, which can solve the defect of insufficient output torque of rotary dampers. At the same time, the structure proposed in this invention is relatively simple, so that the damper can be as small and compact as possible while meeting the output requirements. Attached Figure Description

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0026] Appendix Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention;

[0027] Appendix Figure 2 This is a schematic diagram of the valve mode operation according to an embodiment of the present invention;

[0028] Appendix Figure 3 This is a schematic diagram of the hybrid working mode of an embodiment of the present invention;

[0029] Appendix Figure 4 This is a schematic diagram of an assembly according to an embodiment of the present invention;

[0030] Appendix Figure 5 This is a schematic diagram of the structure of the outer casing end cap;

[0031] Appendix Figure 6 This is a schematic cross-sectional view of the end cap AA.

[0032] Appendix Figure 7 This is a three-dimensional schematic diagram of the first-stage flow channel baffle;

[0033] Appendix Figure 8 This is a three-dimensional schematic diagram of the gap magnetic blocking sheet;

[0034] Appendix Figure 9 This is a three-dimensional schematic diagram of the second-stage flow channel baffle;

[0035] In the diagram: 1-Outer shell, 2-Large sealing ring, 3-Large arc-shaped magnetic guide block, 4-Coil frame, 5-Excitation coil, 6-Flow channel baffle with second type of flow hole, 7-Gap magnetic barrier plate, 8-Flow channel baffle with first type of flow hole, 9-Magnetorheological fluid, 10-Sector block rotor, 11-Flat key, 12-Rotating shaft, 13-Small arc-shaped magnetic guide block, 14-Outer shell end cap, 15-Hex socket head cap screw, 16-Bearing end cap, 17-Small O-ring seal, 18-Bearing. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0038] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0039] As shown in the figure, the rotary magnetorheological damper with a hybrid operating mode includes a multi-channel stator, a sector block rotor, and a rotating shaft 12. The rotating shaft drives the sector block rotor to rotate under an external load, causing a change in the distance between the multi-channel stator and the sector block rotor. The rotation angle of the rotating shaft is detected by an angle sensor and forms a feedback signal sent to the current controller. The outer side of the multi-channel stator is connected to the outer shell cylinder 1 via a large arc-shaped magnetic guide block 3 and fixed to the inner wall of the outer shell cylinder. The inner side is tightly attached to the rotating shaft via a small arc-shaped magnetic guide block 13. The outer side of the sector block rotor 10 is tightly attached to the inner wall of the outer shell cylinder, and the inner side is connected to the rotating shaft.

[0040] The multi-channel stator has multiple flow channels formed by gaps, and an excitation coil for generating a magnetic field is wound on the outside; the current of the excitation coil is controlled by a current controller; the outer shell is filled with magnetorheological fluid 9 whose viscosity can be changed by a magnetic field; the rotating shaft drives the sector block rotor to rotate, so that the magnetorheological fluid flows in the gaps.

[0041] When the distance between the multi-channel stator and the sector block rotor increases to the point that the main body of the magnetic circuit passes through the multi-channel stator and the large and small arc-shaped magnetic guide blocks, a valve mode is formed in the gap within the multi-channel stator; that is, the magnetorheological fluid in the gap within the multi-channel stator forms a high-viscosity state under the action of the magnetic field, so as to reduce the flow velocity of the magnetorheological fluid in the gap and thus provide damping force.

[0042] When the distance between the multi-channel stator and the sector block rotor decreases to the point where the main magnetic circuit also passes through the sector block rotor, a squeezing mode is simultaneously formed at the gap between the multi-channel stator and the sector block rotor. Specifically, the magnetic field of the excitation coil changes to increase the viscosity of the magnetorheological fluid, causing the magnetorheological fluid at the gap between the multi-channel stator and the sector block rotor to approach a solidified state. This causes the high-viscosity magnetorheological fluid flowing through the gap between the multi-channel stator and the sector block rotor to be in a squeezing mode, thereby increasing the damping force of the damper.

[0043] The outer casing is connected to the outer casing end cap 14 at both ends, and the outer casing end cap is connected to the bearing end cap 16; a bearing 18 is installed between the bearing end cap and the rotating shaft; the inner side of the sector block rotor is connected to the rotating shaft through a flat key 11.

[0044] The large arc-shaped magnetic conductor, the small arc-shaped magnetic conductor, the multi-channel stator, and the sector-shaped rotor are all arranged in pairs and are symmetrically distributed along the shaft diameter.

[0045] The multi-channel stator includes a coil frame 4, an excitation coil 5, and also includes a plurality of flow channel baffles with flow holes and a plurality of gap magnetic blocking plates 7 disposed in the coil frame; the flow holes of the flow channel baffles disposed in the coil frame are divided into multiple categories according to their distribution or specifications.

[0046] The coil frame has grooves of a preset depth for winding the excitation coil on its exterior; the coil frame has a hollow interior structure, and the flow channel baffles and magnetic blocking plates are sequentially stacked and installed in the hollow interior structure of the coil frame in the order of flow channel baffle 8 with a first type of flow hole, gap magnetic blocking plate, and flow channel baffle 6 with a second type of flow hole, forming a multi-stage gap flow channel for the magnetorheological fluid to flow.

[0047] The flow channel baffle with the first type of flow hole has an arc-shaped flow hole in the middle position; the flow channel baffle with the second type of flow hole has an arc-shaped flow hole in the top position near the outer shell and the bottom position near the rotating shaft; the gap baffle is a rectangular frame with a slightly thicker outer side and a slightly thinner inner side.

[0048] The side of the large arc-shaped magnetic block that contacts the multi-channel stator has a wedge-shaped slot for radial positioning and installation of the multi-channel stator.

[0049] The inner wall of the outer shell that contacts the large arc-shaped magnetic block is provided with a wedge-shaped groove for radial positioning and installation of the large arc-shaped magnetic block; both ends of the outer shell are provided with several threaded holes; both ends of the outer shell are provided with sealing ring grooves for installing sealing rings.

[0050] In this example, large O-rings are installed in the sealing grooves at both ends of the outer casing for sealing the magnetorheological fluid.

[0051] A fan-shaped groove is provided on the side of the outer casing end cover that connects to the outer casing cylinder for axial positioning and installation of the large arc-shaped magnetic guide block, the small arc-shaped magnetic guide block, and the multi-channel stator; the outer casing end cover has several threaded through holes; a sealing ring groove is provided at the junction of the outer casing end cover and the rotating shaft for installing the sealing ring.

[0052] In this example, a 60° fan-shaped groove is provided on the side of the outer casing end cap that connects to the outer casing, for axial positioning and installation of the large arc-shaped magnetic guide block, the small arc-shaped magnetic guide block, and the multi-channel stator; a small O-ring 17 is installed in the sealing ring groove provided at the junction of the outer casing end cap and the rotating shaft for sealing the magnetorheological fluid.

[0053] A double keyway is provided on the shaft segment connecting the rotating shaft and the sector block rotor.

[0054] In this example, a standard flat key is installed in the double keyway, and the sector block rotor is driven to rotate through the key connection when the shaft rotates.

[0055] A control method for a rotary magnetorheological damper with a hybrid operating mode, using the rotary magnetorheological damper with a hybrid operating mode described above, is characterized in that: when the damper is in valve mode, the excitation current of the excitation coil is a preset value, which can be adjusted to change the viscosity of the magnetorheological fluid in valve mode to adjust the damping.

[0056] When the rotor moves to near its limit position, that is, when the gap angle between the sector block rotor and the multi-channel stator is lower than the threshold, the damper operates in a mixed mode combining valve mode and compression mode. The excitation coil increases the current based on the original excitation current to increase the damping output force and form a larger damping torque, and protect the device.

[0057] In this example, the damper receives external load excitation, and the rotating shaft drives the sector block rotor to rotate. At the same time, the angle sensor detects the angle through which the rotating shaft rotates and generates a feedback signal that is transmitted to the current controller. When the angle through is small, the sector block rotor is far from the multi-channel stator, and the damper mainly operates in valve mode, with a given excitation current. When the angle through is large, the sector block rotor is close to the multi-channel stator, approaching the limit position, and the angle between them is less than the set 3°. In this case, the damper operates in hybrid mode, where the current is increased based on the original current, thereby increasing the output torque of the magnetorheological damper and simultaneously protecting the device.

[0058] In summary, this invention proposes a rotary magnetorheological damper with a hybrid operating mode and its control method. By designing a multi-stage gap flow channel formed by flow channel baffles and the arrangement of coils, the damper can simultaneously have two different operating modes, resulting in a larger output torque and a relatively smaller size. This solves the problem of insufficient output power in traditional shear rotary magnetorheological dampers.

[0059] The above description is merely a preferred embodiment of the present invention and a detailed explanation of the purpose, technical solution, and advantages of the present invention. It should be understood that this is not intended to limit the present invention in any other way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention's technical solution shall still fall within the protection scope of the present invention's technical solution.

Claims

1. A rotary magnetorheological damper with hybrid operating modes, characterized in that: It includes a multi-channel stator, a sector block rotor (10), and a rotating shaft (12); the rotating shaft drives the sector block rotor to rotate under the drive of an external load, causing the distance between the multi-channel stator and the sector block rotor to change; the outer side of the multi-channel stator is connected to the outer shell cylinder (1) through a large arc-shaped magnetic block (3) and fixed to the inner wall of the outer shell cylinder, and the inner side is tightly attached to the rotating shaft through a small arc-shaped magnetic block (13); the outer side of the sector block rotor (10) is tightly attached to the inner wall of the outer shell cylinder, and the inner side is connected to the rotating shaft; The multi-channel stator has multiple flow channels formed by gaps, and an excitation coil for generating a magnetic field is wound on the outside; the current of the excitation coil is controlled by a current controller; the outer shell is filled with a magnetorheological fluid (9) whose viscosity can be changed by a magnetic field; the rotating shaft drives the sector block rotor to rotate, so that the magnetorheological fluid flows in the gap. When the distance between the multi-channel stator and the sector block rotor increases to the point that the main body of the magnetic circuit passes through the multi-channel stator and the large and small arc-shaped magnetic guide blocks, a valve mode is formed in the gap within the multi-channel stator; that is, the magnetorheological fluid in the gap within the multi-channel stator forms a high-viscosity state under the action of the magnetic field, so as to reduce the flow velocity of the magnetorheological fluid in the gap and thus provide damping force. When the distance between the multi-channel stator and the sector block rotor decreases to the point that the main body of the magnetic circuit also passes through the sector block rotor, a squeezing mode is simultaneously formed at the gap between the multi-channel stator and the sector block rotor. Specifically, the magnetic field of the excitation coil changes to increase the viscosity of the magnetorheological fluid, so that the magnetorheological fluid at the gap between the multi-channel stator and the sector block rotor is close to a solidified state, and the high-viscosity magnetorheological fluid flowing through the gap between the multi-channel stator and the sector block rotor is in a squeezing mode to increase the damping force of the damper. The multi-channel stator includes a coil frame (4), an excitation coil (5), and also includes a number of flow channel baffles with flow holes and a number of gap magnetic blocking plates (7) provided in the coil frame; the flow holes of the flow channel baffles provided in the coil frame are divided into multiple categories according to their distribution or specifications; The coil frame has a groove of a preset depth for winding the excitation coil on its outside; the coil frame has a hollow structure inside, and the flow channel baffle and magnetic blocking plate are stacked and installed in the hollow structure inside the coil frame in the order of flow channel baffle (8) with first type of flow hole, gap magnetic blocking plate, and flow channel baffle (6) with second type of flow hole, to form a multi-level gap flow channel.

2. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: The outer casing is connected to the outer casing end cap (14) at both ends, and the outer casing end cap is connected to the bearing end cap (16); a bearing (18) is installed between the bearing end cap and the rotating shaft; the inner side of the sector block rotor is connected to the rotating shaft through a flat key (11).

3. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: The large arc-shaped magnetic conductor, the small arc-shaped magnetic conductor, the multi-channel stator, and the sector-shaped rotor are all arranged in pairs and are symmetrically distributed along the shaft diameter.

4. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: The flow channel baffle with the first type of flow hole has an arc-shaped flow hole located in the middle position; the flow channel baffle with the second type of flow hole has an arc-shaped flow hole located at the top near the outer shell and at the bottom near the rotating shaft.

5. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: The side of the large arc-shaped magnetic block that contacts the multi-channel stator has a wedge-shaped slot for radial positioning and installation of the multi-channel stator.

6. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: The inner wall of the outer shell cylinder that contacts the large arc-shaped magnetic block is provided with a wedge-shaped groove for radial positioning and installation of the large arc-shaped magnetic block.

7. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: A fan-shaped groove is provided on the side of the outer casing end cover that connects to the outer casing cylinder for axial positioning and installation of the large arc-shaped magnetic guide block, the small arc-shaped magnetic guide block, and the multi-channel stator; the outer casing end cover has several threaded through holes; a sealing ring groove is provided at the junction of the outer casing end cover and the rotating shaft for installing the sealing ring.

8. The rotary magnetorheological damper with hybrid operating mode according to claim 1, characterized in that: A double keyway is provided on the shaft segment connecting the rotating shaft and the sector block rotor.

9. A control method for a rotary magnetorheological damper with a hybrid operating mode, employing the rotary magnetorheological damper with a hybrid operating mode as described in claims 1, 2, 3, 4, 5, 6, 7, or 8, characterized in that: When the damper operates in valve mode, the excitation current of the excitation coil is a preset value. When the rotor moves to near its limit position, that is, when the gap angle between the sector block rotor and the multi-channel stator is lower than the threshold, the damper operates in a mixed mode combining valve mode and compression mode. The excitation coil increases the current based on the original excitation current to increase the damping output force and form a larger damping torque, and protect the device.

Images