Connecting base with controllable damping channel, shock absorber and damping adjusting method

Abstract

The invention discloses a connecting base with a controllable damping channel, and belongs to the technical field of damping vibration attenuation, the connecting base is provided with a hollow inner cavity, the surface of the hollow inner cavity is provided with two or more mounting ports communicated with the inner cavity, and the mounting ports can be externally connected with equipment with magneto-sensitive fluid media respectively. The connecting base is provided with an inner cavity, a fluid channel for transferring a magneto-sensitive fluid medium is formed in the inner cavity, the connecting base is further provided with a magnetic field generating device, and the magnetic field generating device can apply a controllable magnetic field to magneto-sensitive fluid flowing through the fluid channel so as to change the rheological property of the magneto-sensitive fluid. By the adoption of the technical scheme, the shock absorber has the advantages of being high in damping adjustment response speed, large in movement stroke and the like. When the scheme is used for upgrading an existing product, the original working cylinder assembly and the original compensation air chamber assembly including the working cylinder, the piston, the piston rod, the guide sealing device, the floating piston, the compensation air chamber and the like can be reused, and the economical efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of damping and vibration reduction technology, and in particular to a connecting base with a controllable damping channel, a vibration damper, and a damping adjustment method. Background Technology

[0002] Magnetorheological dampers are widely used in building, bridge, and vehicle vibration reduction due to their fast response, simple structure, low energy consumption, and strong controllability. Their structures are mainly divided into single-rod and double-rod types. The single-rod structure, because it needs to compensate for the change in oil chamber volume when the piston rod enters and exits the working cylinder, often requires a compensation chamber in its design. A floating piston is used to isolate the oil and gas between the compensation chamber and the oil chamber. When the installation space at both ends of the damper is limited or the damper requires a large stroke, the floating piston and compensation chamber are often placed outside the working cylinder to avoid occupying the axial space of the damper. To improve assemblability and reliability, dampers with a side-mounted compensation chamber generally use a connecting base to connect the working cylinder and the compensation chamber together. However, the damping characteristics of the above-mentioned structure are not adjustable during operation, which cannot meet the adjustable damping requirements for vibration reduction in complex road conditions.

[0003] Existing technologies employ two different schemes to achieve adjustable damping characteristics of the aforementioned damper structure. One approach replaces the piston valve assembly with a piston assembly featuring an electromagnetic winding. A damping channel is incorporated within the piston assembly, and magnetorheological fluid is used as the working fluid in the cylinder. During damper operation, the energizing current of the electromagnetic winding is adjusted according to different requirements. The magnetic field generated by this energizing current directly affects the mechanical properties of the magnetorheological fluid passing through the damping channel within the piston assembly, thereby altering the damping characteristics of the damper and outputting the desired damping force, thus achieving damping adjustment. This approach has the following drawbacks: the axial length of the piston with the electromagnetic winding is typically longer than that of the piston valve assembly, which reduces the maximum stroke of the damper; and the piston rod usually needs to be redesigned to meet the assembly requirements with the new-sized piston.

[0004] The second method involves adding an adjustable foot valve to the connecting base. When the damper compresses or returns to its original position, oil of the same magnitude as the change in the size of the oil chamber caused by the piston rod moving in and out of the working cylinder will pass through the foot valve into and out of the compensation cylinder. Adjusting the foot valve can change the resistance when the oil enters and exits the foot valve, thereby achieving the damping adjustment function. This technical solution has the following disadvantages: the foot valve is not easy to achieve stepless adjustment; the foot valve is not easy to achieve real-time adjustment; and the adjustment response speed of the foot valve is relatively slow. Summary of the Invention

[0005] The purpose of this invention is to solve the problems existing in the vibration damper of the side-mounted compensation air chamber. To achieve the above objective, the present invention adopts the following technical solution: A connecting base with a controllable damping channel, the connecting base having a hollow internal cavity, and having two or more mounting ports on its surface that connect to the internal cavity, the mounting ports being able to externally connect to devices with magnetically sensitive fluid media, and forming a fluid channel for the transfer of magnetically sensitive fluid media in the internal cavity; The connecting base is equipped with a magnetic field generating device, which can apply a controllable magnetic field to the magnetically sensitive fluid flowing through the fluid channel to change the rheological properties of the magnetically sensitive fluid.

[0006] Preferably, the magnetic field generating device includes a magnetically conductive component and an excitation winding wound on the magnetically conductive component, and the magnetic damping channel is formed between the magnetically conductive component and the inner wall of the connecting base.

[0007] Preferably, the fluid channel is an annular channel or a slit channel.

[0008] A vibration damper with a controllable damping channel includes: The working cylinder contains the working fluid medium. A compensation chamber is used to compensate for changes in the internal volume of the working cylinder; The connecting base has a hollow internal cavity and two or more mounting ports that connect to the internal cavity, respectively connecting the working cylinder and the compensation chamber, and forming a fluid channel for medium transfer in the internal cavity; A magnetic field generating device is mounted on the connecting base and is used to apply a controllable magnetic field to the working medium passing through the fluid channel; The working medium is a magnetically sensitive fluid. The rheological properties of the working medium in the fluid channel are changed by adjusting the magnetic field strength generated by the magnetic field generating device, thereby adjusting the damping force of the shock absorber.

[0009] Preferably, the magnetic field generating device includes a magnetically conductive component and an excitation winding wound around the magnetically conductive component.

[0010] Preferably, the magnetic conductive member is disposed in the internal cavity of the connecting base, and the fluid channel is formed between the magnetic conductive member and the inner wall of the connecting base.

[0011] Preferably, the fluid channel is an annular channel or a slit channel.

[0012] Preferably, the compensation chamber is disposed next to the working cylinder, and the axis of the compensation chamber is parallel to or at a preset angle to the axis of the working cylinder.

[0013] Preferably, the compensation chamber is provided with an isolation element that divides the compensation chamber into a medium chamber and a gas chamber, and the medium chamber is connected to the working cylinder through the fluid channel.

[0014] Preferably, the isolation element is a floating piston, which can move axially along the compensation chamber.

[0015] Preferably, the device further includes a piston assembly disposed within the working cylinder, the piston assembly dividing the interior of the working cylinder into a first chamber and a second chamber, the piston assembly having a non-adjustable damping channel connecting the first chamber and the second chamber, and the total damping force of the shock absorber being formed by the superposition of the damping force generated by the non-adjustable damping channel and the adjustable damping force generated by the fluid channel.

[0016] A damping adjustment method, applied to a vibration damper with a controllable damping channel, the method comprising: S1: Obtain the target damping force requirement; S2: Determine the excitation current of the magnetic field generating device according to the target damping force requirement; S3: Apply the corresponding excitation current to the magnetic field generating device, so that the vibration damper outputs a damping force that matches the target damping force requirement.

[0017] The technical solution provided by this invention has the following significant advantages over the prior art: 1. The magnetic field generating device is integrated into the connecting base. Since the connecting base is located outside the axial direction of the working cylinder, it does not occupy the axial space inside the working cylinder. Therefore, the piston valve assembly can maintain its original size, and the maximum stroke of the shock absorber is unaffected. A larger effective stroke can be obtained with the same axial installation dimensions. Furthermore, the adjustable damping channel is formed by the gap between the magnetic guide frame and the inner wall of the connecting base, resulting in a simple structure with no complex moving parts, thus reducing the failure rate. The excitation winding is fixedly installed inside the connecting base and does not move with the piston, avoiding reliability issues such as lead wire fatigue fracture.

[0018] 2. Regardless of whether the damper is in the recovery stroke or the compression stroke, the magnetorheological fluid flows through the adjustable damping channel. Therefore, both the recovery damping force and the compression damping force can be controlled by adjusting the excitation current, thus achieving bidirectional controllable damping.

[0019] 3. Only the connecting base needs to be replaced or improved; the remaining major components can utilize the mature design of existing products. High component versatility facilitates product serialization and standardized production, reducing manufacturing and inventory management costs. Furthermore, since the damping adjustment mechanism is centrally located within the connecting base, it is relatively independent from the working cylinder and compensation air chamber. When maintenance or replacement of the damping adjustment components is required, the connecting base can be disassembled separately for maintenance, eliminating the need to disassemble the entire shock absorber, thus reducing maintenance difficulty and costs.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a vibration damper structure with a damping channel provided by the present invention; Figure 2 This is a diagram showing the distribution of chambers and channels in the damping channel damper provided by the present invention; Figure 3 This is a schematic diagram of the recovery stroke of the vibration damper with damping channel provided by the present invention; Figure 4 This is a schematic diagram of the compression stroke of the vibration damper with damping channel provided by the present invention.

[0022] Figure label: 1. Lifting ring; 2. Connecting base; 3. Working cylinder; 4. Piston valve assembly; 5. Piston rod; 6. Guide sealing assembly; 7. Compensation chamber; 8. Floating piston; 9. Magnetic guide frame; 10. Excitation winding; a. Oil chamber one; b. Oil chamber two; c. Oil chamber three; d. Gas chamber; e. Adjustable damping channel; f. Non-adjustable damping channel. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by those skilled in the art. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are only used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections. If a part has a central axis or a hollow cavity, then the "inner side" of the part refers to the side of the part closer to the central axis of the part or the part disposed inside the hollow cavity.

[0024] Example 1 This embodiment provides a connecting base with a controllable damping channel. The connecting base is generally block-shaped or cylindrical, including a shell part and a magnetic field generating device. The shell part has a hollow internal cavity, and two or more mounting ports that can communicate with the internal cavity are opened on the surface of the shell. The mounting ports are used to assemble other devices with magnetically sensitive fluid media. When the mounting ports are connected to other devices with magnetically sensitive fluid media, a fluid channel for fluid media transfer is formed in the internal cavity. In particular, when there are two or more mounting ports, a continuous and sequentially connected fluid channel can be formed according to actual needs, or several independent fluid channels can be formed.

[0025] The magnetic field generating device includes a magnetically conductive component and an excitation winding wound on the magnetically conductive component. Specifically, the magnetically conductive frame is a cylindrical or ring-shaped structure made of magnetically conductive material. The excitation winding is wound around the magnetically conductive frame, and its leads are led out through sealed wire holes on the connecting base to the outside and electrically connected to the controller. When the excitation winding is energized, it generates a magnetic field. Magnetic lines of force pass sequentially through the magnetically conductive frame and the body of the connecting base, forming a closed magnetic circuit. The magnetic field generating device is mounted on the housing portion, and the magnetic field it generates can act on a magnetically sensitive fluid medium passing through the fluid channel, thereby altering the rheological properties of the magnetically sensitive fluid.

[0026] Specifically, in order to better apply the magnetic field to the magnetically sensitive fluid, the magnetic field generating device is installed inside the housing, specifically at the fluid channel. A magnetic damping channel is automatically formed between the magnetically conductive frame and the inner wall of the housing. The shape of the magnetic damping channel can be annular or slit-shaped, depending on the installation position and connection method of the magnetically conductive frame and the inner wall of the housing.

[0027] The connecting base provided in this embodiment can connect two devices with magnetically sensitive fluids, and change the damping of the medium flow in the two devices by influencing the rheological properties of the magnetically sensitive fluids through a magnetic field generating device.

[0028] Example 2 This embodiment provides a vibration damper with a controllable damping channel, such as... Figure 1-2 As shown, the main structure of the shock absorber includes: a lifting ring 1, a connecting base 2, a working cylinder 3, a piston valve assembly 4, a piston rod 5, a guide sealing assembly 6, a compensating air chamber 7, a floating piston 8, a magnetic skeleton 9, and an excitation winding 10.

[0029] The working cylinder 3 has a cylindrical structure, with one end sealed by a guide sealing assembly 6. The piston rod 5 extends out of the working cylinder 3 through the guide sealing assembly 6. The inner end of the piston rod 5 is connected to the piston valve assembly 4, which can reciprocate along the axial direction of the working cylinder 3. The other end of the working cylinder 3 is sealed to a mounting port of the connecting base 2. The specific connection is not limited and can be a threaded connection, welding, interference fit, or flange connection. The oil chamber of the working cylinder 3 is divided by the piston valve assembly 4 into an oil chamber a away from the connecting base 2 and an oil chamber b close to the connecting base 2. The oil chamber b is directly connected to the internal chamber of the connecting base 2, and the magnetically sensitive fluid medium therein is a magnetorheological fluid.

[0030] The compensating chamber 7 is a cylindrical structure with its axis parallel to the axis of the working cylinder 3, forming a side-mounted layout. One end of the compensating chamber 7 is closed to form a gas chamber, and the other end is sealed to another mounting port of the connecting base 2. The specific connection is not limited and can be a threaded connection, welding, interference fit, or flange connection. A floating piston 8 is installed inside the compensating chamber 7, dividing it into an oil chamber (c) near the connecting base 2 and a gas chamber (d) away from the connecting base 2. The gas chamber is filled with high-pressure inert gas. The floating piston 8 can slide axially along the inner wall of the compensating chamber 7, and a sealing ring is provided on its outer circumference. The oil chamber (c) is directly connected to the internal chamber of the connecting base 2.

[0031] The connecting base 2 is the same as the connecting base provided in Embodiment 1. Its body has a block structure and a through fluid channel is opened inside. The fluid channel includes an inlet section, a damping adjustment section and an outlet section. The inlet section is connected to the oil chamber 2b of the working cylinder 3 through the mounting port, and the outlet section is connected to the oil chamber 3c of the compensation air chamber 7.

[0032] The magnetically conductive frame 9 is located inside the damping adjustment section of the connecting base 2. The magnetically conductive frame 9 has a cylindrical structure, is made of magnetically conductive material, and forms an annular magnetic damping channel between its outer circumference and the inner wall of the connecting base 2; this is the adjustable damping channel e. The specific dimensions of the radial clearance and axial length of the adjustable damping channel e are determined according to the damping force adjustment range and flow requirements.

[0033] The excitation winding 10 is wound around the magnetic guide frame 9 and is made of enameled copper wire. The number of turns is determined according to the damping force adjustment range and flow requirements. The lead wires of the excitation winding 10 are led out to the outside through the sealed wire hole on the connecting base 2 and electrically connected to the controller. After the excitation winding 10 is energized, it generates a magnetic field. The magnetic lines of force pass through the magnetic guide frame 9, the magnetorheological fluid in the adjustable damping channel e, and the body of the connecting base 2 in sequence to form a closed magnetic circuit.

[0034] like Figure 2As shown, the piston valve assembly 4 is disposed inside the working cylinder 3, dividing the internal space of the working cylinder 3 into oil chamber 1a and oil chamber 2b. The outer circumferential surface of the piston valve assembly 4 is provided with piston rings, which slide and seal with the inner wall of the working cylinder 3.

[0035] More specifically, the piston valve assembly 4 is equipped with a non-adjustable damping channel f, including a recovery valve channel and a compression valve channel. The recovery valve channel contains a recovery valve plate assembly, and the compression valve channel contains a compression valve plate assembly. The recovery valve plate assembly and the compression valve plate assembly respectively control the flow direction and flow rate of the oil during the recovery stroke and compression stroke, generating a basic damping force. Oil chambers a, b, and c are connected through the non-adjustable damping channel f and the adjustable damping channel e to form a single oil chamber.

[0036] In this embodiment, the piston valve assembly 4 adopts the conventional structure of the prior art, without the need for redesign, and can directly use existing products, thereby improving the versatility of components.

[0037] More specifically, the guide sealing assembly 6 includes a guide sleeve and a seal. The guide sleeve is fixed to the end opening of the working cylinder 3 by threads or a retaining ring. The inner hole of the guide sleeve slides with the piston rod 5. The seal dynamically seals the gap between the piston rod 5 and the guide sleeve.

[0038] In this embodiment, the guide sealing assembly 6 adopts the conventional structure of the prior art, without the need for redesign, and can directly use existing products, thereby improving the versatility of components.

[0039] More specifically, the lifting ring 1 is fixedly connected to the outer wall of the housing of the connecting base 2, and is used to install on equipment that requires vibration reduction.

[0040] The working principle of the vibration damper in Example 2 will be explained next.

[0041] The working principle of vibration dampers is as follows: Figure 2 and Figure 3 As shown, this is a sectional view of a plane. When describing the direction of motion of an object, for the convenience of description, the terms "up," "down," "left," or "right" as intuitively reflected in the figure are used. These terms only indicate the positional changes reflected in the figure and do not indicate the absolute direction of the object's motion.

[0042] 1. Restoration of the itinerary process: like Figure 3 As shown, when the shock absorber is in its recovery stroke, the external load causes the piston rod 5 to extend outward, driving the piston valve assembly 4 to move to the right along the axis of the working cylinder 3 at a speed V1 (away from the connecting base 2, which will not be described further). The changes in the entire system at this time include two parts: First, there's the change in volume of oil chamber 1a and the generation of the non-adjustable damping force F1. As the piston valve assembly 4 moves to the right, the volume of oil chamber 1a decreases, compressing the magnetorheological fluid within and increasing its pressure. When the pressure difference reaches the opening pressure of the reset valve assembly, the reset valve assembly opens, and the magnetorheological fluid in oil chamber 1a flows into oil chamber 2b through the reset valve channel on the piston valve assembly 4. That is, the magnetorheological fluid passing through the non-adjustable damping channel f generates an non-adjustable damping force F1.

[0043] Secondly, there is the volume compensation of oil chamber three c and the generation of adjustable damping force F2. As piston rod 5 extends outward, its volume within working cylinder 3 decreases, leading to an increase in the total volume of the working chamber composed of oil chamber one a and oil chamber two b. This necessitates the replenishment of magnetorheological fluid from the oil chamber. The high-pressure gas in the gas chamber of compensation gas chamber 7 acts on the floating piston 8, pushing it to move to the left at a speed V2 (towards the connecting base 2, which will not be elaborated further). The leftward movement of the floating piston 8 reduces the volume of oil chamber three c, squeezing out the magnetorheological fluid within it. This fluid flows into oil chamber two b of working cylinder 3 through the adjustable damping channel e within the connecting base 2. When the magnetorheological fluid flows through the adjustable damping channel e, the magnetic field generated by the excitation winding 10 acts on the magnetorheological fluid within the channel. The ferromagnetic particles in the magnetorheological fluid align along the magnetic field lines under the influence of the magnetic field, forming a chain-like structure, giving the magnetorheological fluid solid-like properties and significantly increasing flow resistance. That is, the magnetorheological fluid flowing through the adjustable damping channel e generates an adjustable damping force F2.

[0044] After the above changes, the total damping force F of the recovery stroke is formed by the superposition of the non-adjustable damping force F1 and the adjustable damping force F2. F1 is determined by the structural parameters of the piston valve assembly 4 and is a fixed value; F2 is determined by the current in the excitation winding 10 and can be adjusted in real time. Increasing the excitation current increases the magnetic field strength, increases the yield stress of the magnetorheological fluid, increases F2, and increases the recovery damping force; decreasing the excitation current decreases F2 and reduces the recovery damping force.

[0045] The macroscopic change of the system is represented as follows: when the piston valve assembly 4 moves from position A1 to the right to position A2, the floating piston 8 moves from position B1 to the left to position B2.

[0046] 2. Compression stroke working process like Figure 4 As shown, when the shock absorber is in the compression stroke, the external load causes the piston rod 5 to retract inward, driving the piston valve assembly 4 to move to the left along the axis of the working cylinder 3 at a speed of V3. The changes in the entire system at this time include two parts: First, there's the change in oil chamber 2b and the generation of the non-adjustable damping force F3. As the piston valve assembly 4 moves to the left, the volume of oil chamber 2b decreases, compressing the magnetorheological fluid and increasing its pressure. When the pressure difference reaches the opening pressure of the compression valve assembly, the compression valve assembly opens, and some of the magnetorheological fluid flows into oil chamber 1a through the compression valve channel on the piston valve assembly 4, generating the non-adjustable damping force F3.

[0047] Secondly, there is the discharge of excess oil and the generation of adjustable damping force F4. As the piston rod 5 retracts inward, its volume within the working cylinder 3 increases, resulting in a decrease in the total volume of the working chamber composed of oil chamber a and oil chamber b. Excess magnetorheological fluid in the working chamber is squeezed out and flows into oil chamber c of the compensation gas chamber 7 through the adjustable damping channel e in the connecting base 2. The magnetorheological fluid flowing into oil chamber c pushes the floating piston 8 to move to the right at a speed V4, compressing the gas in the gas chamber. The rightward movement of the floating piston 8 increases the volume of the oil chamber, accommodating the excess magnetorheological fluid discharged from the working cylinder 3. When the magnetorheological fluid flows through the adjustable damping channel e, the flow direction is opposite to the return stroke, and it is also affected by the magnetic field generated by the excitation winding 10, generating adjustable damping force F4.

[0048] After the above changes, the total damping force F' of the compression stroke is formed by the superposition of the non-adjustable damping force F3 and the adjustable damping force F4. F3 is determined by the structural parameters of the piston valve assembly 4 and is a fixed value; F4 is determined by the current in the excitation winding 10 and can be adjusted in real time. Increasing the excitation current increases the magnetic field strength, increases the yield stress of the magnetorheological fluid, increases F4, and increases the compression damping force F'; decreasing the excitation current decreases F4 and the compression damping force F'.

[0049] The macroscopic change of the system is represented as follows: when the piston valve assembly 4 moves from position A3 to the left to position A4, the floating piston 8 moves from position B3 to the right to position B4.

[0050] Example 3 This embodiment three also provides a damping adjustment method applied to the vibration damper of embodiment two. The adjustment process is as follows: S1: Obtain the target damping force requirement; S2: Determine the excitation current of the magnetic field generating device according to the target damping force requirement; S3: Apply the corresponding excitation current to the magnetic field generating device so that the damper outputs a damping force that matches the target damping force requirement.

[0051] The following is a detailed description of an application in a vehicle.

[0052] The controller collects vehicle driving status signals in real time, including but not limited to: vehicle body acceleration, suspension travel, wheel acceleration, vehicle speed, etc., and calculates the target damping force under the current operating condition based on the collected status signals and preset control strategies (such as ceiling control, floor control, hybrid control, etc.).

[0053] The computer system then determines the required excitation current value for the excitation winding 10 based on the target damping force and the pre-calibrated damping force-current characteristic curve.

[0054] The controller's drive circuit outputs a corresponding excitation current to the excitation winding 10. The excitation current generates a magnetic field, which changes the rheological properties of the magnetorheological fluid in the adjustable damping channel e, thereby causing the damper to output a damping force that matches the target value.

[0055] During vehicle operation, the controller continuously monitors the vehicle status and adjusts the excitation current in real time, enabling rapid, continuous, and stepless damping adjustment.

[0056] It should be noted that, for this invention, the core inventive concept is that the magnetic field generating device within the connecting base and its housing form an adjustable damping channel. The overall structure of the connecting base is an important technical feature of this invention and is described in detail in the specification. Some conventional mechanical structures and connection methods of the working cylinder and the compensation air chamber are briefly or omitted in the specification. In addition, the method of controlling the excitation current is a well-known technology in the field and is not the focus of protection of this invention, so it is only briefly described in the specification. It should be understood that, in addition to the structures mentioned in the specification, this invention also includes the necessary structures for adjusting the current, as well as other structures and components not mentioned but reasonable in the field or well-known to those skilled in the art. Those skilled in the art are familiar with how to change the magnitude of the excitation current, and the omission of detailed descriptions in the specification will not prevent those skilled in the art from understanding the technical solution.

[0057] Finally, it should be noted that the described embodiments are merely some, not all, of the embodiments of the present invention. Those skilled in the art will understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents; that is, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A connection base with a controllable damping channel, characterized in that, The connecting base has a hollow internal chamber, and two or more installation ports are formed on the surface of the connecting base and communicate with the internal chamber; each installation port can be externally connected to a device having a magnetically sensitive fluid medium, and a fluid passage for the transfer of the magnetically sensitive fluid medium is formed in the internal chamber; A magnetic field generating device is arranged on the connecting base, and a controllable magnetic field can be applied to the magnetically sensitive fluid flowing through the fluid passage to change the rheological properties of the magnetically sensitive fluid.

2. The connection base of claim 1, wherein: The magnetic field generating device includes a magnetic conducting member and an excitation winding wound on the magnetic conducting member, and a magnetic damping passage is formed in the interior of the magnetic conducting member or between the magnetic conducting member and the inner wall of the connecting base.

3. A shock absorber having a controllable damping passage, characterized by Comprise: a working cylinder containing a fluid medium; a compensation chamber for compensating for the change in cylinder volume caused by the piston rod entering and exiting the working cylinder; a connecting base having a hollow internal chamber and two or more installation ports formed on the surface of the connecting base and communicating with the internal chamber, respectively connecting the working cylinder and the compensation chamber, and forming a fluid passage in the internal chamber for the transfer of the medium; a magnetic field generating device arranged on the connecting base for applying a controllable magnetic field to the working medium passing through the fluid passage; wherein the working medium is a magnetically sensitive fluid, and the rheological properties of the working medium in the fluid passage are changed by adjusting the magnetic field strength generated by the magnetic field generating device, thereby adjusting the damping force of the shock absorber.

4. The damper of claim 3, wherein The magnetic field generating device includes a magnetic conducting member and an excitation winding wound on the magnetic conducting member.

5. The damper of claim 4, wherein The magnetic conducting member is arranged in the internal chamber of the connecting base, and a magnetic damping passage is formed in the interior of the magnetic conducting member or between the magnetic conducting member and the inner wall of the connecting base.

6. The damper of claim 5, wherein The magnetic damping passage is an annular passage or a slit passage.

7. The damper of claim 3, wherein The compensation chamber is provided with a partition, which divides the compensation chamber into a medium chamber and a gas chamber, and the medium chamber communicates with the working cylinder through the fluid passage.

8. The damper of claim 7, wherein The partition is a floating piston, which can move axially along the compensation chamber.

9. The damper of claim 3, wherein Further comprising a piston assembly arranged in the working cylinder, which divides the working cylinder into a first chamber and a second chamber, and an unadjustable damping passage is provided on the piston assembly and communicates with the first chamber and the second chamber, and the total damping force of the shock absorber is formed by superimposing the damping force generated by the unadjustable damping passage and the adjustable damping force generated by the fluid passage.

10. A method of damping adjustment, characterized by The method is applied to the shock absorber of any one of claims 3-9, and the method comprises: S1: obtaining a target damping force requirement; S2: determining an excitation current of the magnetic field generating device according to the target damping force requirement; S3: applying the corresponding excitation current to the magnetic field generating device, so that the shock absorber outputs a damping force matching the target damping force requirement.

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