Mechanical stepless adjustment valve-type passive magnetorheological damper

Abstract

The present invention discloses a mechanical stepless adjustment valve plate type passive magnetorheological damper, comprising a cylinder, a piston assembly and an adjustment assembly, wherein magnetorheological fluid is arranged in the cylinder; the piston assembly comprises a piston body, the piston body is provided with a permanent magnet, and the piston body is arranged in the cylinder in a manner that can slide along the axial direction of the cylinder; the adjustment assembly comprises an adjustment valve plate, the adjustment valve plate is arranged on the axial front side of the piston body and is located in the cylinder, and the axial gap between the adjustment valve plate and the piston body constitutes an adjustment channel, and the adjustment valve plate can be adjusted close to or away from the piston body; the present invention replaces the excitation coil in the traditional magnetorheological damper with a permanent magnet to generate a working magnetic field, thereby solving the problems of serious heating, easy short circuit and open circuit of the magnetorheological damper; the present invention adjusts the output damping force by adjusting the size of the working gap between the adjustment valve plate and the piston body, which not only can realize stepless adjustment of the output damping force, but also has a wider adjustment range.

Description

Technical Field

[0001] The invention belongs to the technical field of dampers and relates to a mechanical stepless adjustment valve-plate passive magnetorheological damper. Background Art

[0002] A magnetorheological damper (MRD) is a semi-active intelligent device that uses magnetorheological fluid as its primary working medium, providing resistance to motion and dissipating kinetic energy. Currently, the most common operating modes of the magnetorheological fluid in an MRD are flow, extrusion, and shear. MRDs operating in these different modes exhibit significant performance differences. Designing an MRD in the appropriate operating mode, tailored to the operating conditions, can further enhance its effectiveness.

[0003] MRDs typically adjust the output damping force by varying the coil current. As the excitation current gradually increases, the magnetorheological effect strengthens, and the MRD's output damping force also gradually increases. The excitation coil is typically wound within a wire slot on the piston. When the excitation current is applied to the coil to generate the operating magnetic field, the heat generated by the coil further increases the damper temperature and, in severe cases, can cause the coil to short-circuit. Furthermore, this arrangement not only requires an external power supply, but the magnetorheological fluid can also erode and corrode the coil, shortening the MRD's service life. These issues have, to a certain extent, limited the widespread application of MRDs.

[0004] To solve the above problems, a new type of magnetorheological damper is needed, which replaces the existing excitation coil with a simple structure and a fixed magnetic field source, so that the magnetorheological damper can work without external drive and the damping is adjustable, which is conducive to the further promotion and application of magnetorheological technology. Summary of the Invention

[0005] In view of this, the present invention provides a mechanically stepless adjustable valve plate type passive magnetorheological damper, which generates a working magnetic field by replacing the excitation coil in the traditional magnetorheological damper with a permanent magnet, and realizes the variable gap function by adjusting the valve plate to achieve stepless adjustment of the output damping force. The overall structure is simpler, the subsequent maintenance cost is low, and it is more green and safe.

[0006] The present invention provides a mechanical stepless adjustment valve-type passive magnetorheological damper, comprising:

[0007] a cylinder, wherein a magnetorheological fluid is disposed in the cylinder;

[0008] A piston assembly, comprising a piston body provided with a permanent magnet, the piston body being slidably disposed in the cylinder along the axial direction of the cylinder;

[0009] The regulating assembly includes a regulating valve plate, which is arranged on the axial front side of the piston body and located in the cylinder. The axial gap between the regulating valve plate and the piston body constitutes a regulating channel, and the regulating valve plate can be adjusted close to or away from the piston body.

[0010] Furthermore, the piston assembly also includes a piston end cover, which is installed at the axial front end of the piston body. A regulating cavity is formed between the piston end cover and the piston body, and the regulating valve plate is arranged in the regulating cavity.

[0011] Furthermore, it also includes a sealing seat, and the piston assembly is also provided with a piston rod, and the sealing seat is arranged on the axial rear side of the piston body; one end of the piston rod is connected to the piston end cover, and the other end extends axially forward to the outside of the cylinder.

[0012] Furthermore, the adjustment assembly also includes an adjustment rod and an elastic member I, the piston rod has an axially arranged mounting channel, the adjustment rod is arranged in the mounting channel in a manner that can be driven to swing circumferentially, the end of the adjustment rod is provided with an external thread, the end of the adjustment rod extends axially into the adjustment cavity, and the adjustment valve plate is installed on the end of the adjustment rod in a threaded connection manner; the piston body has a hollow cavity, the elastic member is arranged in the cavity, the elastic member abuts against the axial end face of the adjustment valve plate and provides an axial preload; the drive rod swings so that the adjustment valve plate is driven closer to or away from the piston body.

[0013] Furthermore, it also includes an end cover and a cylinder bottom for sealing the cylinder, the end cover is installed at the axial front end of the cylinder, and the cylinder bottom is installed at the axial rear end of the cylinder; the piston body and the sealing seat are arranged in sequence from front to back in the cylinder and divide the cylinder into a recovery chamber, a compression chamber and a compensation chamber, and the magnetorheological fluid is arranged in the recovery chamber and the compression chamber.

[0014] Furthermore, it also includes a compensation component, which includes a compensation rod, an elastic part II and a pre-tightening screw. The elastic part II is arranged in the compensation cavity to provide axial elastic force. The elastic part is provided with a compensation channel. The front end of the compensation rod is connected to the piston body, and the rear end of the compensation rod extends axially backward through the sealing seat and then extends into the compensation cavity. The pre-tightening screw is installed at the bottom of the cylinder and abuts against the axial rear end of the elastic part II.

[0015] Furthermore, the adjustment assembly also includes an adjustment handle and a guide rod. The adjustment handle is installed at the front of the adjustment rod and is located outside the cylinder. One end of the guide rod is connected to the piston end cover, and the other end extends to the piston body after axially passing through the adjustment valve plate.

[0016] Furthermore, the sealing seat extends forward in the axial direction to form a flange, and the flange is provided with a plurality of flow holes in the circumferential direction.

[0017] Furthermore, the piston end cover is provided with an inlet for the magnetorheological fluid to flow from the recovery chamber into the regulating chamber, and the piston body is provided with an outlet for the magnetorheological fluid to flow into the compression chamber.

[0018] Furthermore, the permanent magnet is circumferentially arranged in the cavity of the piston body and located between the piston body and the elastic member I.

[0019] Beneficial effects of the present invention:

[0020] The present invention discloses a mechanical stepless adjustable valve plate type passive magnetorheological damper, which uses permanent magnets to replace the excitation coils in traditional magnetorheological dampers to generate a working magnetic field, thereby solving the problems of severe heating, easy short circuit and open circuit of the magnetorheological damper; the present invention adjusts the output damping force by adjusting the size of the working gap between the regulating valve plate and the piston body, does not require an external power supply, has low subsequent maintenance costs, and is more environmentally friendly and safe; the use of a variable gap method can not only achieve stepless adjustment of the output damping force, but also has a wider adjustment range. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2 Schematic diagram of the flow of the magnetorheological fluid of the present invention;

[0023] Figure 3 Schematic diagram of the structure of the piston end cover of the present invention;

[0024] Figure 4 This is a schematic structural diagram of the sealing seat of the present invention;

[0025] 1-Front earring, 2-Adjusting handle, 3-Adjusting rod, 4-End cover, 5-Piston rod, 6-Cylinder, 7-Fasten screw, 8-Permanent magnet, 9-Sealing seat, 10-Cylinder bottom, 11-Adjusting screw, 12-Rear earring, 13-Elastic part II, 14-Compensating rod, 15-Clamping ring, 16-Piston body, 17-Elastic part I, 18-Guide rod, 19-Adjusting valve plate, 20-Piston end cover, 21-Optical axis, 22-Recovery chamber, 23-Compression chamber. DETAILED DESCRIPTION

[0026] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 Schematic diagram of the flow of the magnetorheological fluid of the present invention; Figure 3 Schematic diagram of the structure of the piston end cover of the present invention; Figure 4Schematic diagram of the structure of the sealing seat of the present invention; reference numerals: 1-front earring, 2-adjusting handle, 3-adjusting rod, 4-end cover, 5-piston rod, 6-cylinder, 7-fastening screw, 8-permanent magnet, 9-sealing seat, 10-cylinder bottom, 11-adjusting screw, 12-rear earring, 13-elastic part II, 14-compensating rod, 15-clamping ring, 16-piston body, 17-elastic part I, 18-guide rod, 19-adjusting valve plate, 20-piston end cover, 21-optical axis, 22-recovery chamber, 23-compression chamber.

[0027] The present invention provides a mechanical stepless adjustment valve-type passive magnetorheological damper, comprising:

[0028] a cylinder 6, wherein a magnetorheological fluid is disposed in the cylinder 6;

[0029] The piston assembly includes a piston body 16, which is provided with a permanent magnet 8. The piston body 16 is arranged in the cylinder 6 in a manner that can slide along the axial direction of the cylinder 6; by providing the permanent magnet 8 instead of the excitation coil in the traditional magnetorheological damper to generate a working magnetic field, no external source is required, and at the same time, the problem of severe heating, easy short circuit and open circuit of the magnetorheological damper is solved.

[0030] The regulating assembly includes a regulating valve plate 19, which is arranged on the axial front side of the piston body 16 and is located in the cylinder 6. The axial gap between the regulating valve plate 19 and the piston body 16 constitutes an regulating channel, and the regulating valve plate 19 can be adjusted to be close to or away from the piston body 16. The regulating valve plate 19 can be adjusted to be close to or away from the piston body 16, that is, the axial gap between the regulating valve plate 19 and the piston body 16, that is, the size of the regulating channel is adjusted. When the magnetorheological fluid flows through the regulating channel, due to the change in size, the magnetorheological fluid flowing through here will generate different fluid damping forces accordingly, so that the present invention can achieve the adjustment of the output damping force, and the damping adjustment is stepless adjustment, and no external power supply is required for damping adjustment. The subsequent maintenance cost is low, it is more green and safe, and the adjustment range is wider.

[0031] In this embodiment, the piston assembly also includes a piston end cover 204, which is installed on the end face of the axial front end of the piston body 16 by screws 7. An adjusting chamber is formed between the piston end cover 204 and the piston body 16, and the adjusting valve plate 19 is arranged in the adjusting chamber. The setting of the adjusting chamber plays a role in limiting and protecting the adjusting valve plate 19. It not only limits the movement stroke of the adjusting valve plate 19, but also prevents the adjusting valve plate 19 from colliding with the end cover 4 when the piston moves to the extreme position, affecting the adjustment accuracy and service life of the adjusting valve plate 19. After the adjusting chamber is set, the above situation is avoided.

[0032] In this embodiment, a sealing seat 9 is also included, and the piston assembly is also provided with a piston rod 5. The sealing seat 9 is arranged on the axial rear side of the piston body 16. At the same time, in this embodiment, a retaining ring 15 is provided on the axial front side of the sealing seat 9 to form a limit for the sealing seat; one end of the piston rod 5 is inserted into the end face of the piston end cover 204 away from the piston body 16, and the other end extends axially forward to the outside of the cylinder 6. The piston rod 5 can be connected to the working position and transmit vibration to drive the piston to slide, thereby achieving the effect of energy absorption and vibration reduction. This is understandable to technicians in this technical field and will not be elaborated here. In this embodiment, the piston end cover 204 extends in the direction of the piston rod 5 to form a mounting boss 2001, and an internal threaded hole is provided on the mounting boss. The piston rod 5 is connected to the piston end cover 204 in a threaded connection.

[0033] In this embodiment, the adjustment assembly also includes an adjustment rod 3 and an elastic member I17. The piston rod 5 has an axially arranged mounting channel. The adjustment rod 3 is arranged in the mounting channel in a manner that can be driven to swing circumferentially. The end of the adjustment rod 3 is provided with an external thread. The end of the adjustment rod 3 extends axially into the adjustment cavity. The adjustment valve plate 19 is installed at the end of the adjustment rod 3 in a threaded connection manner; the piston body 16 has a hollow cavity, and the elastic member is arranged in the cavity. The elastic member abuts against the axial end face of the adjustment valve plate 19 and provides an axial preload; the drive rod swings so that the adjustment valve plate 19 is driven close to or away from the piston body 16. The regulating valve disc 19 is installed at the end of the regulating rod 3 in a threaded connection manner, and the elastic member I17 provides an axial pre-tightening force to press the regulating valve disc 19, so that when the regulating rod 3 swings, the regulating valve disc 19 is moved closer to or away from the piston body 16 under the action of the threaded structure, thereby realizing the function of adjusting the size of the aforementioned regulating channel, and also realizing the adjustment of the damping force. The regulating rod 3 in this embodiment adopts a screw rod and the elastic member adopts a spring. Due to the threaded installation method, the spring is set to eliminate the meshing gap between the threads of the regulating valve disc 19 and the regulating rod 3. At the same time, in order to ensure smooth swinging, this embodiment also has an optical axis 21 sleeved on the outside of the regulating rod 3 to support the regulating rod 3, ensuring its swinging function while avoiding its direct contact with the piston rod 5.

[0034] In this embodiment, an end cap 4 and a cylinder bottom 10 for sealing the cylinder 6 are further included. The end cap 4 is mounted at the axial front end of the cylinder 6, and the cylinder bottom 10 is mounted at the axial rear end of the cylinder 6. The piston body 16 and the sealing seat 9 are sequentially arranged in the cylinder 6 from front to back and divide the cylinder 6 into a recovery chamber 22, a compression chamber 23, and a compensation chamber. The magnetorheological fluid is arranged in the recovery chamber 22 and the compression chamber 23. The sealing seat 9 is used to isolate the magnetorheological fluid to improve the overall sealing performance of the device. The magnetorheological fluid flows back and forth in the compression chamber 23 and the recovery chamber 22 as the piston slides. That is, it enters the recovery chamber 22 after passing through the piston body 16 and the adjustment chamber from the compression chamber 23; or it enters the compression chamber 23 after passing through the adjustment chamber and the compression body from the recovery chamber 22.

[0035] This embodiment also includes a compensation assembly, comprising a compensation rod 14, an elastic member II 13, and a preload screw 11. The elastic member II 13 is disposed within the compression chamber 23 to provide an axial elastic force. The front end of the compensation rod 14 is connected to the piston body 16, and the rear end of the compensation rod 14 extends axially rearward through the sealing seat 9 and into the compensation chamber. The preload screw 11 is mounted on the cylinder bottom 10 and abuts against the axial rear end of the elastic member II 13. In this embodiment, the compensation rod 14 has the same diameter as the piston rod 5 and is connected to the piston body 16 via threads to compensate for changes in the damper working chamber volume caused by the piston rod 5 entering and exiting the cylinder 6. The elastic member II is composed of multiple disc springs arranged in a positive and negative arrangement, disposed within the compensation chamber and preloaded by the preload screw 11 to compensate for volume changes caused by temperature changes within the damper. Two or more preload screws 11 are provided, preferably symmetrically to ensure consistent preload force at all locations on the elastic member II 13. This is a technical approach readily understood by those skilled in the art and will not be elaborated upon here.

[0036] In this embodiment, the adjustment assembly further includes an adjustment handle 2 and a guide rod 18. The adjustment handle 2 is mounted in front of the adjustment rod 3 and located outside the cylinder 6. One end of the guide rod 18 is connected to the piston end cap 204, and the other end axially passes through the adjustment valve disc 19 and extends to the piston body 16. The adjustment handle 2 facilitates the swinging of the adjustment rod 3. At the same time, to prevent the adjustment valve disc 19 from rotating with the rotation of the adjustment rod 3, the guide rod 18 guides it, thereby limiting the movement of the adjustment valve disc 19 to the axial direction and preventing rotation.

[0037] In this embodiment, the sealing seat 9 extends axially forward to form a flange, and the flange is provided with a plurality of flow holes along the circumference. The provision of the flange prevents the sealing seat 9 from directly abutting against the rear end of the piston body 16, thereby ensuring the existence of the compression chamber 23.

[0038] In this embodiment, the piston end cover 204 is provided with an inlet for the magnetorheological fluid to flow from the recovery chamber 22 into the regulating chamber, and the piston body 16 is provided with an outlet for the magnetorheological fluid to flow into the compression chamber 23. In this embodiment, the inlet is an arc-shaped waist-shaped hole parallel to the radial outer edge of the piston end cover, and there are two inlets, which are symmetrically opened on the piston end cover 204. Figure 3 As shown; the piston body 16 of this embodiment has a hollow chamber, and its outlet is opened at the center position of the axial rear end face. At the same time, due to the existence of the compensation rod 14, in order to ensure the flow of the magnetorheological fluid, this embodiment also opens a channel and a through hole on the compensation rod 14, and connects with the outlet to facilitate the flow of the magnetorheological fluid. In this embodiment, the flange is set on the sealing seat to prevent the compensation rod from sliding completely into the sealing seat during operation, thereby causing the through hole for the magnetorheological fluid to enter the compression chamber to be blocked, and the magnetorheological fluid cannot circulate. This is understandable to technicians in this technical field and will not be elaborated here.

[0039] In this embodiment, the permanent magnet 8 is circumferentially arranged in the cavity of the piston body 16 and located between the piston body 16 and the elastic member I 17. Figure 2 As shown, a permanent magnet 8 is circumferentially arranged in the cavity of the piston body 16, and a through hole is provided in the axial direction of the permanent magnet 8 for placing the elastic member I17 and for the flow of magnetorheological fluid. When the magnetorheological fluid flows, it flows directly over the surface of the permanent magnet 8, making the damping effect more prominent and the magnetic field will not be blocked.

[0040] In this embodiment, grooves for installing seals and guides are processed on the outer cylindrical surfaces of the piston body 16 and the sealing seat 9, which improve the overall sealing performance of the present invention and facilitate guidance. Figure 1 As shown, taking the end cover 4 as an example, in this embodiment, in order to facilitate the sliding of the piston rod 5, a channel is opened in the axial direction of the end cover 4, the piston rod is inserted into the channel, and a sealing groove 401 for installing a sealing strip and a guide groove 402 for installing a guide belt are opened in the channel, and a silent groove 403 for installing a static seal is provided on the radial outer surface of the end cover. The number, setting position and setting method of the sealing grooves, guide grooves and silent grooves can be selected and adjusted according to actual conditions; and, in this embodiment, not only the end cover is provided with the aforementioned grooves, but the piston body, sealing seat or other components with sealing and guiding requirements can also be provided. This is understandable to technicians in this technical field and will not be elaborated here. A front earring 1 is installed at the front end of the piston rod 5, and a rear earring 12 is installed at the bottom of the cylinder 10. The front and rear earrings 12 are provided to facilitate the installation of the damper of the present invention in the working position; in this embodiment, in order to make the damper of the present invention smoother during operation, the piston rod 5, the piston body 16, the sealing seat 9, the compensation rod 14, the elastic part I 17 and the elastic part II 13 are all coaxially arranged with the cylinder 6.

[0041] The following further illustrates the present invention's stretching motion. As the piston body 16 moves leftward, the pressure in the restoring chamber 22 increases. The magnetorheological fluid then flows from the restoring chamber 22 through the piston end cap 204, the regulating channel between the regulating valve plate 19 and the piston end face, the piston body, and the compensation rod 14, before entering the compression chamber 23. As the damper returns to its original position, the pressure in the compression chamber 23 increases, and the magnetorheological fluid flows in the opposite direction along the same path into the restoring chamber 22.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A mechanical stepless adjustable valve-type passive magnetorheological damper, characterized by: include: a cylinder, wherein a magnetorheological fluid is disposed in the cylinder; A piston assembly, comprising a piston body provided with a permanent magnet, the piston body being slidably disposed in the cylinder along the axial direction of the cylinder; an adjusting assembly, the adjusting assembly including an adjusting valve disc, the adjusting valve disc being arranged at the axial front side of the piston body and located within the cylinder, the adjusting valve disc and the piston body being spaced apart in the axial direction to form an adjusting passage, and the adjusting valve disc being adjustable to move closer to or further away from the piston body; The piston assembly further includes a piston end cover, which is mounted on the axial front end of the piston body. A regulating cavity is formed between the piston end cover and the piston body. The regulating valve plate is disposed in the regulating cavity. The axial gap between the regulating valve plate and the piston body forms a regulating channel. The piston assembly further includes a sealing seat, and the piston rod is provided. The sealing seat is provided on the axial rear side of the piston body; one end of the piston rod is connected to the piston end cover, and the other end extends forward in the axial direction to the outside of the cylinder; The adjustment assembly further includes an adjustment rod and an elastic member I. The piston rod has an axially arranged mounting channel. The adjustment rod is arranged in the mounting channel in a manner that can be driven to swing circumferentially. The end of the adjustment rod is provided with an external thread. The end of the adjustment rod extends axially into the adjustment cavity. The adjustment valve disc is mounted on the end of the adjustment rod in a threaded connection manner. The piston body has a hollow cavity. The elastic member is arranged in the cavity. The elastic member abuts against the axial end surface of the adjustment valve disc and provides an axial preload. The adjustment rod swings to drive the adjustment valve disc closer to or away from the piston body. The sealing seat extends forward in the axial direction to form a flange, and the flange is provided with a plurality of flow holes in the circumferential direction.

2. The mechanical stepless adjustable valve plate passive magnetorheological damper according to claim 1, characterized in that: It also includes an end cover and a cylinder bottom for sealing the cylinder, the end cover is installed at the axial front end of the cylinder, and the cylinder bottom is installed at the axial rear end of the cylinder; the piston body and the sealing seat are arranged in sequence from front to back in the cylinder and divide the cylinder into a recovery chamber, a compression chamber and a compensation chamber, and the magnetorheological fluid is arranged in the recovery chamber and the compression chamber.

3. The mechanical stepless adjustable valve plate passive magnetorheological damper according to claim 2, characterized in that: It also includes a compensation component, which includes a compensation rod, an elastic part II and a pre-tightening screw. The elastic part II is arranged in the compensation cavity to provide axial elastic force. The front end of the compensation rod is connected to the piston body, and the rear end of the compensation rod extends axially backward through the sealing seat and then extends into the compensation cavity. The pre-tightening screw is installed at the bottom of the cylinder and abuts against the axial rear end of the elastic part II.

4. The mechanical stepless adjustable valve plate passive magnetorheological damper according to claim 3, characterized in that: The adjustment assembly also includes an adjustment handle and a guide rod. The adjustment handle is installed in front of the adjustment rod and is located outside the cylinder. One end of the guide rod is connected to the piston end cover, and the other end extends to the piston body after axially passing through the adjustment valve plate.

5. The mechanical stepless adjustable valve plate passive magnetorheological damper according to claim 4, characterized in that: The piston end cover is provided with an inlet for the magnetorheological fluid to flow from the recovery chamber into the regulating chamber, and the piston body is provided with an outlet for the magnetorheological fluid to flow into the compression chamber.

6. The mechanical stepless adjustable valve-type passive magnetorheological damper according to claim 5, characterized in that: The permanent magnet is circumferentially arranged in the cavity of the piston body and located between the piston body and the elastic member I.

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