Frequency response adjustable damper

Abstract

This invention discloses a frequency-responsive adjustable damper, relating to the field of vehicle suspension technology. It includes a cylinder, piston, piston rod, and main valve. The piston divides the cylinder into an upper chamber and a lower chamber. The main valve includes a compression valve system and a return valve system. A frequency-responsive valve is integrated on the piston compression side, comprising a valve seat, a housing, a base, a sealing ring, and a frequency-adjustable valve assembly. The valve seat has a channel close to the piston's fixed center. The housing, valve seat, and piston form a first chamber connecting to the upper chamber. The base connects to the lower end of the housing, and its center forms a second chamber with the valve seat and piston. The outer periphery of the base, housing, and valve seat channel form a fourth chamber connecting to the lower chamber. The sealing ring slides around the outer periphery of the base, separating the two chambers. The frequency-adjustable valve assembly is located between the sealing ring and the base, controlling the oil circuits of the second to fourth chambers during piston return. This valve also has a pressure balance space, connected to the second chamber and linked with the frequency-adjustable valve assembly, responding to the piston frequency to control opening and closing. This invention solves the problems of poor adjustment, space occupation, and small adjustable range of external or return-side frequency valves.

Description

Technical Field

[0001] This invention relates to the field of vehicle suspension technology, specifically to a frequency-response adjustable damper. Background Technology

[0002] The damper is a core component of the vehicle suspension system. Its main function is to suppress and attenuate the relative motion between the vehicle body and wheels by consuming vibration energy, thereby improving ride comfort and handling stability. Current mainstream hydraulic dampers typically include a cylinder, piston, piston rod, and a valve system mounted on the piston. The piston divides the cylinder cavity into an upper and lower chamber, and compression and recovery valve systems with fixed characteristics are respectively installed on its compression and recovery sides. Its basic working principle is: when the piston rod is subjected to external force and reciprocates, it forces hydraulic fluid to flow between the upper and lower chambers through the throttling orifices or gaps on the valve system, consuming mechanical energy through the viscous resistance (i.e., damping force) generated by the fluid flow. However, the damping characteristics of traditional valve systems are fixed during manufacturing; their damping force is only a function of the piston's velocity, exhibiting a single "velocity-damping force" curve, unable to intelligently respond to the frequency components of the input vibration.

[0003] To improve ride quality, particularly the vehicle's ability to filter high-frequency short-wave vibrations, existing technologies have developed frequency-sensitive valves that are externally mounted or integrated into the recovery valve. These valves typically use pre-set valve bodies of several different specifications, allowing selection during vehicle tuning to optimize damping characteristics within a specific frequency range. However, this approach has significant drawbacks: First, its frequency response range is discrete and limited, preventing continuous and precise adjustment and resulting in imperfect vehicle matching. Second, the external or recovery-side mounting method encroaches on the valuable guide length of the shock absorber, potentially leading to insufficient design margin. Finally, due to its structural principles, the adjustable range of damping force (especially the reduction margin) often falls short of ideal levels (e.g., ≥30%), limiting its performance optimization potential. Therefore, to address the aforementioned problems, a frequency-responsive adjustable damper is provided. Summary of the Invention

[0004] The technical problem to be solved by this invention is that existing hydraulic dampers, especially external or frequency-sensitive valves integrated into the piston return side, have problems such as discrete frequency response ranges and inconvenient adjustment leading to imperfect vehicle compatibility, installation occupying guide length affecting design margin, and limited adjustable damping force range. Therefore, a frequency-response adjustable damper is proposed.

[0005] The purpose of this invention is to provide a frequency-response adjustable damper to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a frequency-responsive adjustable damper, comprising a cylinder, a piston disposed within the cylinder, a piston rod connected to the piston, and a main valve disposed on the piston. The piston divides the inner cavity of the cylinder into an upper cavity and a lower cavity. The main valve has a compression valve system disposed on the compression side of the piston and a recovery valve system disposed on the recovery side of the piston. A frequency-responsive valve is integrated on the compression side of the piston. The frequency response valve includes a valve seat, a housing, a base, a sealing ring, and a frequency-modulated valve plate assembly. The valve seat is fixed close to the piston and has an axial channel. The housing, the valve seat, and the piston together form a first chamber that communicates with the upper cavity. The base is connected to the lower end of the housing. The center of the base and the valve seat and piston channel form an annular second chamber. The outer periphery of the base, the inner side of the housing, and the axial channel of the valve seat together form a fourth chamber that communicates with the lower cavity. The sealing ring is slidably sleeved on the outer periphery of the base to isolate the second chamber from the fourth chamber. The frequency modulation valve plate group is set between the sealing ring and the valve seat to control the opening and closing of the oil passage from the second chamber to the fourth chamber when the piston returns to its original position. The frequency response valve also has a pressure balance space between the sealing ring and the valve seat. The pressure balance space is connected to the second chamber and is linked with the frequency modulation valve plate group to control the opening and closing of the frequency modulation valve plate group in response to the piston movement frequency.

[0007] As a preferred embodiment of the present invention, a support valve plate is provided between the sealing ring and the bushing. The support valve plate provides preload to the frequency modulation valve plate assembly, and the outer diameter of the support valve plate is larger than the radius of action of the oil pressure from the second chamber on the frequency modulation valve plate assembly.

[0008] As a preferred embodiment of the present invention, the pressure balance space includes a sealed third chamber and a damping channel. The third chamber is formed by a sealing ring, a valve seat, a supporting valve plate, and a sealing valve plate. The damping channel connects the second chamber and the third chamber, and the flow area of ​​the damping channel is smaller than the flow area when the frequency modulation valve plate group is open.

[0009] As a preferred embodiment of the present invention, the damping channel is a throttling groove formed on the slotted valve plate, and the slotted valve plate is fixed on the valve seat and located between the second chamber and the third chamber.

[0010] As a preferred embodiment of the present invention, at least one flow guide valve is provided on the side of the slotted valve plate near the second chamber. The flow guide valve is provided with a flow guide port for guiding the oil in the second chamber to the throttling groove of the slotted valve plate.

[0011] As a preferred embodiment of the present invention, the upper end of the valve seat is provided with an annular sealing strip that cooperates with the piston rod, and the annular sealing strip and the piston rod are sealed with zero gap by axial compression.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention solves the problem that existing frequency-sensitive valves occupy guide length and affect the overall design margin and reliability of the shock absorber when they are externally placed or integrated on the recovery side by setting a frequency response valve integrated on the piston compression side. 2. By setting up a pressure balance space inside the frequency response valve and communicating with the second chamber, and a frequency-adjusting valve plate group controlled by the pressure of this space, a mechanical hydraulic response mechanism sensitive to the piston movement frequency is formed. This solves the problems of existing dampers having a fixed frequency response range and low adjustability, which prevents the vehicle adaptation and debugging from reaching the optimal state, and the full-speed domain damping force adjustment range being difficult to meet high-performance requirements. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of the cylinder barrel according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of the frequency response valve according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of the outer casing according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of the base according to an embodiment of the present invention; Figure 5 This is a cross-sectional view of the sealing ring according to an embodiment of the present invention; Figure 6 This is a cross-sectional view of the valve seat according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the flow guide valve plate structure according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the oil circuit according to an embodiment of the present invention; Figure 9 Embodiments of the present invention Figure 8 Enlarged view of point A in the middle; Figure 10 Embodiments of the present invention Figure 8 Enlarged view at point B in the middle; Figure 11 Embodiments of the present invention Figure 8 Enlarged view at point C; Figure 12 Embodiments of the present invention Figure 8 Enlarged view at point D; Figure 13 This is a force-displacement curve diagram of an embodiment of the present invention; Figure 14 This is a force-frequency curve diagram of an embodiment of the present invention.

[0014] In the diagram: 1. Cylinder; 2. Frequency response valve; 201. Housing; 202. Base; 203. Sealing ring; 204. Sealing ring; 205. Support valve plate; 206. Valve seat; 207. Frequency modulation valve plate assembly; 208. Washer; 209. Bushing; 210. Slotted valve plate; 211. Flow guide valve plate; 212. Sealing valve plate; 3. Upper chamber; 4. Lower chamber; 5. First chamber; 6. Second chamber; 7. Third chamber; 8. Fourth chamber; F1. First oil passage; F2. Second oil passage; F3. Third oil passage; F4. Fourth oil passage. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please see Figures 1-14 This embodiment provides a frequency-response adjustable damper, including a cylinder 1, a piston disposed within the cylinder 1, a piston rod connected to the piston, and a main valve disposed on the piston. For example... Figure 1 As shown, the piston divides the inner cavity of cylinder 1 into an upper chamber 3 and a lower chamber 4. The main valve has a compression valve system located on the piston compression side and a recovery valve system located on the piston recovery side. A frequency response valve 2 is integrated on the piston compression side.

[0017] Among them, such as Figure 1 and Figure 2 As shown, the frequency response valve 2 includes a valve seat 206, a housing 201, a base 202, a sealing ring 204, and a frequency modulation valve plate assembly 207. The valve seat 206 is fixed close to the piston and has an axial channel. The housing 201, the valve seat 206, and the piston together form a first chamber 5 that communicates with the upper chamber 3. The outer shape of the housing 201 matches the contour of the piston compression side, providing installation and working space for the compression valve system. The inner side of the housing 201 has a stepped structure, providing sufficient and optimized space for oil flow, avoiding increased flow resistance and unstable damping force due to insufficient space.

[0018] The base 202 is connected to the lower end of the housing 201. The center of the base 202, the valve seat 206, and the piston form an annular second chamber 6. The outer contour of the base 202, the inner contour of the housing 201, and the axial channel of the valve seat 206 together form a fourth chamber 8 that communicates with the lower chamber 4. The end of the base 202 is provided with an air hole, and the inner side of the end of the base 202 is designed with a step structure. This step structure ensures that the subsequently installed sealing valve plate 212 can be reliably pressed and sealed to prevent oil leakage and ensure the airtightness of the third chamber 7.

[0019] The sealing ring 204 is slidably fitted onto the outer circumference of the base 202, isolating the second chamber 6 from the fourth chamber 8. The inner diameter of the sealing ring 204 is precisely matched with the outer diameter of the base 202 to achieve a sliding seal. Bosses are provided on both sides of the end of the sealing ring 204, with the diameter of the outer boss being smaller than that of the inner boss. This design allows the sealing ring 204 to stably support the valve plates at both ends and ensures that the oil flows along the designed path. The sliding seal design allows the sealing ring 204 to float axially within a certain range, thereby automatically compensating for machining and assembly tolerances and ensuring that the valve system maintains good sealing performance even after long-term operation. The sealing ring 204 forms a sliding and static seal with the outer shell 201 and the base 202 through the sealing ring 203.

[0020] A frequency-modulated valve assembly 207, located between the sealing ring 204 and the valve seat 206, is composed of multiple valve plates and controls the opening and closing of the oil passages from the second chamber 6 to the fourth chamber 8 during the piston's return motion. The frequency-modulated valve assembly 207 is the primary actuator for frequency response. When a sufficient pressure difference is generated between the second chamber 6 and the third chamber 7, the frequency-modulated valve assembly 207 closes under the preload and liquid pressure provided by the supporting valve plate 205. When the pressure difference decreases, the frequency-modulated valve assembly 207 opens, allowing oil to flow rapidly from the second chamber 6 to the fourth chamber 8. By replacing the frequency-modulated valve assembly 207 with different thicknesses, quantities, or stiffnesses, the pressure threshold and response frequency required for valve system opening can be precisely adjusted, thereby achieving differentiated damping responses to different vibration frequencies. This design greatly expands the adjustable range of the damper, allowing the damping force adjustment range across the entire speed range to easily reach or exceed 30%, meeting customers' needs for high-performance tuning.

[0021] The frequency response valve 2 also has a pressure balance space disposed between the sealing ring 204 and the valve seat 206. This pressure balance space communicates with the second chamber 6 and is linked to the frequency modulation valve assembly 207 to control the opening and closing of the frequency modulation valve assembly 207 in response to the piston movement frequency. The pressure balance space includes a sealed third chamber 7 and a damping channel. A support valve 205 is disposed between the sealing ring 204 and the bushing 209. The third chamber 7 is formed by the sealing ring 204, the valve seat 206, the support valve 205, and the sealing valve 212. The sealing valve 212 covers the vent at the end of the base 202. The function of the sealing valve 212 is to prevent oil leakage through the vent and to ensure that the third chamber 7 becomes a completely sealed oil space. The airtightness of the third chamber 7 is crucial for generating the response pressure difference. The damping channel connects the second chamber 6 and the third chamber 7, and the flow area of ​​the damping channel is much smaller than the flow area when the frequency modulation valve assembly 207 is open.

[0022] Specifically, the damping channel is a throttling groove formed on the slotted valve plate 210. The slotted valve plate 210 is fixed on the valve seat 206 and located between the second chamber 6 and the third chamber 7. The slotted valve plate 210 is one of the core components controlling the frequency response characteristics. By changing the width, number, or shape of the throttling groove on the slotted valve plate 210, the resistance of oil flowing from the second chamber 6 into the third chamber 7 can be precisely adjusted, that is, the speed and magnitude of the pressure difference generated between the second chamber 6 and the third chamber 7 can be adjusted.

[0023] According to the orifice throttling formula, the pressure difference across the throttling channel... With traffic The relationship is: ,in, The dynamic viscosity of the oil. The length of the throttling groove, This is the equivalent diameter of the throttling groove. This is equivalent to setting the "trigger sensitivity" of the frequency response valve 2, enabling the frequency response valve 2 to respond precisely to piston movements of different frequencies.

[0024] Furthermore, at least one guide valve 211 is provided on the side of the slotted valve plate 210 near the second chamber 6. The guide valve 211 has a guide port for guiding the oil in the second chamber 6 to the throttling groove of the slotted valve plate 210. Since the second chamber 6 is mainly composed of the slotted portion on the piston rod, and there are unslotted areas on the piston rod, during assembly, there is a possibility that the throttling groove of the slotted valve plate 210 may be directly opposite the unslotted portion of the piston rod, which would lead to oil circuit interruption and failure of the frequency response valve 2. The guide port design of the guide valve plate 211 ensures that regardless of the assembly angle, the oil in the second chamber 6 can always be guided to the throttling groove of the slotted valve plate 210 through the guide port, thereby ensuring that the oil circuit is always unobstructed and the function is 100% reliable. This is an important design feature of this invention in terms of assembly processability and functional reliability.

[0025] The support valve plate 205 provides preload to the frequency modulation valve plate assembly 207, and the outer diameter of the support valve plate 205 is larger than the radius of action of the oil pressure from the second chamber 6 on the frequency modulation valve plate assembly 207. The support valve plate 205 is a relatively thick valve plate, and its outer edge contacts the boss on the inner side of the sealing ring 204 to form a seal. After the valve system is assembled, the height of the sealing ring 204 is designed to be slightly higher than the central axis, which causes the support valve plate 205 to undergo slight elastic deformation after installation. The force generated by this deformation, on the one hand, makes the support valve plate 205 fit tightly against the boss to achieve a sealing effect; on the other hand, this force is transmitted to the frequency modulation valve plate assembly 207, becoming the restoring force for the frequency modulation valve plate assembly 207 to close. According to the principles of mechanics, ,in, For the action force, For hydraulic pressure, Because the effective working area of ​​the third chamber 7 acting on the support valve plate 205 is greater than the effective working area of ​​the frequency modulation valve plate assembly 207 when it is open, at low frequencies and with a large pressure difference, the closing force provided by the support valve plate 205 (the sum of the oil pressure and the deformation force of the support valve plate 205) is sufficient to keep the frequency modulation valve plate assembly 207 closed. Only at high frequencies and with a sufficiently small pressure difference, when the oil pressure is almost zero, can the opening force acting on the frequency modulation valve plate assembly 207 easily overcome the preload of the support valve plate 205, causing the frequency modulation valve plate assembly 207 to open. This ingenious force balance design is the core mechanical principle for achieving frequency selectivity.

[0026] Between the support valve plate 205 and the frequency modulation valve plate assembly 207, an adjusting washer 208 and a bushing 209 are also provided. The adjusting washer 208 is composed of multiple relatively thick, small-diameter valve plates. The adjusting washer 208 has two main functions: one is to place a slightly larger diameter washer 208 after the frequency modulation valve plate assembly 207 to provide additional tension to the frequency modulation valve plate assembly 207 and fine-tune the stiffness of the frequency modulation valve plate assembly 207. The other is to adjust the axial height of the entire valve plate stack. By changing the thickness of the adjusting washer 208, the initial deformation of the support valve plate 205 can be precisely controlled, thereby regulating the initial preload applied by the support valve plate 205 to the frequency modulation valve plate assembly 207. This can effectively prevent the frequency modulation valve plate assembly 207 from failing to open normally due to excessive preload, or from failing to close tightly and leaking at low frequencies due to insufficient preload. The diameter of bushing 209 is similar to that of adjusting washer 208. Due to its greater height, bushing 209 is used to replace multiple stacked adjusting washers 208 in order to simplify assembly and improve structural stability.

[0027] The upper end of valve seat 206 is provided with an annular sealing strip that mates with the piston rod. After the frequency response valve 2 is assembled with the main piston, axial clamping force is used to achieve a zero-clearance interference fit between the annular sealing strip on valve seat 206 and the piston rod, thereby achieving a static sealing effect. This sealing method does not rely on additional sealing components, simplifies the structure, and can adapt to the actual tolerance of the piston rod, ensuring long-term reliable sealing performance. The lower end of valve seat 206 is designed with a special structure, including two raised annular strips, inner and outer. Deep grooves are opened in the central area between the inner annular strip and the two annular strips. These deep grooves provide a smooth flow channel for the oil discharged from the fourth chamber 8, avoiding eddies and local pressure loss, and ensuring efficient oil discharge.

[0028] The working principle of this frequency response valve 2 is as follows: The specific oil circuit movement flow is as follows: Figure 8 , Figure 9 , Figure 10 , Figure 11 as well as Figure 12 As shown: When the piston returns to its original position (moves upward), the volume of the upper chamber 3 and the first chamber 5 decreases, and the pressure increases; the volume of the lower chamber 4 and the fourth chamber 8 increases, and the pressure decreases. The oil flows under the pressure difference. At this time, there are four main oil paths: First oil circuit F1 (main recovery oil circuit): Oil enters the first chamber 5 from the upper chamber 3, and then flows directly to the lower chamber 4 through the recovery valve system on the piston recovery side. This is the basic and always-present damping force generation path during the recovery stroke.

[0029] Second oil passage F2 (frequency valve inlet): Part of the oil is guided from the first chamber 5 through a specific diversion channel (such as a slot) on the piston return side into the second chamber 6. By adjusting the throttling area of ​​this diversion channel (the diversion channel on the piston return side), the maximum flow rate that the frequency response valve 2 can handle can be preset, thereby finely matching the main valve flow rate.

[0030] The oil entering the second chamber 6 is then divided into two oil paths, namely the third oil path F3 and the fourth oil path F4, which continue to flow. Third oil circuit F3 (pressure balance oil circuit): A stream of oil flows slowly into the sealed third chamber 7 through the throttling groove (i.e., damping channel) on the slotted valve plate 210.

[0031] Fourth oil passage F4 (frequency response drain): Another stream of oil acts on the frequency modulation valve plate group 207, attempting to push the frequency modulation valve plate group 207 open and flow into the fourth chamber 8.

[0032] When the piston movement frequency is low, the oil flowing into the third chamber 7 through the third oil passage F3 quickly brings the pressure in the third chamber 7 to a near-equilibrium with the pressure in the second chamber 6. At this time, the upward force acting on the frequency modulation valve assembly 207 (from the second chamber 6) is less than the downward force acting on the support valve 205 (from the third chamber 7 and the preload of the support valve 205), therefore the frequency modulation valve assembly 207 remains closed, and the fourth oil passage F4 is blocked. Most of the oil is discharged through the first oil passage F1, where the damping force is relatively large.

[0033] When the piston's frequency increases, due to the throttling damping effect of the third oil passage F3, the oil in the third chamber 7 cannot fully respond, resulting in a significantly lower pressure in the third chamber 7 compared to the second chamber 6, thus generating a sufficiently large pressure difference. At this time, the upward force acting on the frequency modulation valve assembly 207 (from the high-pressure second chamber 6) exceeds the downward resultant force (the sum of the low-pressure third chamber 7 and the preload of the supporting valve 205), pushing the frequency modulation valve assembly 207 open and opening the fourth oil passage F4. A large amount of oil can then flow rapidly from the second chamber 6 through the frequency modulation valve assembly 207 to the fourth chamber 8, and then into the lower chamber 4. This is equivalent to connecting a low-resistance channel in parallel with the main valve oil passage, thereby significantly reducing the damping force of the entire damper during high-speed recovery motion and achieving a frequency response characteristic of "soft at high frequencies and hard at low frequencies".

[0034] Compared to existing damping valves, which are typically externally mounted on the recovery side and provide a limited number of fixed frequency response ranges by changing different valve bodies, this invention employs a highly integrated built-in valve body design on the piston compression side. The frequency response function is decomposed into a mechanical-hydraulic system that collaboratively achieves this through a frequency-adjustable valve plate assembly 207, a slotted valve plate 210, a support valve plate 205, and a sealed third chamber 7. This design not only completely solves the problems of external valve bodies occupying space on the recovery side and affecting the damper's guide length and design margin, but also achieves continuous, wide-range linear adjustability of the response frequency and flow split ratio through flexible combinations of valve plate specifications, enabling near-perfect vehicle matching and tuning. Simultaneously, the unique flow guide valve plate 211 design ensures absolute functional reliability, while the adjusting washer 208 and bushing 209 provide precise preload adjustment methods. Therefore, this invention effectively solves the core defects of existing technologies, such as low adjustability, poor adaptability, limited adjustable range of damping force, and impact on guide length.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A frequency-response adjustable damper, comprising a cylinder (1), a piston disposed within the cylinder (1), a piston rod connected to the piston, and a main valve disposed on the piston, wherein the piston divides the inner cavity of the cylinder (1) into an upper cavity (3) and a lower cavity (4), and the main valve has a compression valve system disposed on the piston compression side and a recovery valve system disposed on the piston recovery side, characterized in that: The piston has a frequency response valve (2) integrated on its compression side. The frequency response valve (2) includes a valve seat (206), a housing (201), a base (202), a sealing ring (204), and a frequency modulation valve plate assembly (207). The valve seat (206) is fixed close to the piston. The valve seat (206) is provided with an axial channel. The housing (201), the valve seat (206), and the piston together form a first chamber (5) that communicates with the upper chamber (3). The base (202) is connected to the lower end of the housing (201). The center of the base (202) and the valve seat (206) and piston channel together form an annular second chamber (6). The outer periphery of the base (202), the inner side of the housing (201), and the axial channel of the valve seat (206) together form a fourth chamber (8) that communicates with the lower chamber (4). The sealing ring (204) is slidably sleeved on the outer periphery of the base (202) to isolate the second chamber (6) from the fourth chamber (8). The frequency modulation valve plate group (207) is arranged between the sealing ring (204) and the valve seat (206) to control the opening and closing of the oil passage from the second chamber (6) to the fourth chamber (8) when the piston returns to its original position. The frequency response valve (2) also has a pressure balance space between the sealing ring (204) and the valve seat (206), which is connected to the second chamber (6) and linked with the frequency modulation valve plate group (207) to control the opening and closing of the frequency modulation valve plate group (207) in response to the piston movement frequency.

2. The frequency response adjustable damper according to claim 1, characterized in that: A support valve plate (205) is provided between the sealing ring (204) and the bushing (209). The support valve plate (205) provides preload to the frequency modulation valve plate group (207), and the outer diameter of the support valve plate (205) is greater than the radius of action of the oil pressure from the second chamber (6) on the frequency modulation valve plate group (207).

3. The frequency response adjustable damper according to claim 2, characterized in that: The pressure balance space includes a sealed third chamber (7) and a damping channel. The third chamber (7) is surrounded by a sealing ring (204), a valve seat (206), a supporting valve plate (205), and a sealing valve plate (212). The damping channel connects the second chamber (6) and the third chamber (7), and the flow area of ​​the damping channel is smaller than the flow area when the frequency modulation valve plate group (207) is opened.

4. The frequency response adjustable damper according to claim 3, characterized in that: The damping channel is a throttling groove formed on the slotted valve plate (210), which is fixed on the valve seat (206) and located between the second chamber (6) and the third chamber (7).

5. The frequency-response adjustable damper according to claim 4, characterized in that: At least one flow guide valve (211) is provided on the side of the slotted valve plate (210) near the second chamber (6). The flow guide valve (211) is provided with a flow guide port for guiding the oil in the second chamber (6) to the throttling groove of the slotted valve plate (210).

6. The frequency-response adjustable damper according to claim 5, characterized in that: The upper end of the valve seat (206) is provided with an annular sealing strip that cooperates with the piston rod. By axially pressing, the annular sealing strip and the piston rod achieve a zero-gap seal.

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