A double cylinder hydraulic active damper

Abstract

The present application relates to the technical field of shock absorption, and in particular to a double-cylinder hydraulic active shock absorber, which comprises an outer cylinder, an inner cylinder, a piston unit, a bottom unit and an end cover unit. The inner cylinder is arranged in the outer cylinder, and an outer cavity is formed between the two. The piston unit is movably arranged in the hollow cavity of the inner cylinder, which divides the inner cylinder into an upper inner cavity and a lower inner cavity. The bottom unit is connected to one end of the inner cylinder. The outer peripheral wall of the bottom unit is arranged in a spaced manner with the inner peripheral wall of the outer cylinder to form a first channel. One end of the open end cavity of the end cover unit is connected. The end cover unit is arranged in a spaced manner with the circumferential side of the bottom unit to form a second channel. The end cover unit is arranged in a spaced manner with the circumferential side of the bottom unit to form a third channel. The lower inner cavity, the bottom unit, the third channel, the second channel, the first channel and the outer cavity are sequentially communicated to form an oil discharge channel. The minimum value of the cross section of the oil discharge channel is located in the first channel. In this way, the problem of narrow and small oil passage of the double-cylinder hydraulic active shock absorber is solved, and the problem of poor oil passage is solved.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction technology, and more specifically, to a dual-cylinder hydraulic active vibration damper. Background Technology

[0002] As a core component for improving vehicle comfort and handling, the twin-tube hydraulic active shock absorber, with its hydraulic structure, is widely used in mid-to-high-end passenger vehicles, construction machinery, and other fields due to its high load-bearing capacity and wide damping adjustment range. In the twin-tube hydraulic active shock absorber, the annular space between the outer and inner tubes, and the gap between the bottom-mounted damping unit and the tubes, together constitute the key channels for oil circulation. The flow capacity of the oil discharge channel directly determines the shock absorber's response speed, energy loss, and long-term reliability. Among them, the first channel formed by the outer peripheral wall of the bottom-mounted damping unit and the inner peripheral wall of the outer tube is the core link connecting the bottom-mounted damping unit and the outer cavity in the oil discharge path, and its cross-sectional dimensions play a decisive role in the oil flow resistance.

[0003] In existing twin-cylinder hydraulic active shock absorbers, the end cap unit's open end connects between the outer and inner cylinders. This limited space between the end cap and the inner cylinder results in a narrow channel for oil flow. This narrow channel significantly restricts oil flow efficiency, preventing the oil from flowing quickly and smoothly between the chambers during operation, thus affecting the shock absorber's vibration response speed and damping effect. Increasing the gap between the end cap and the inner cylinder often requires increasing the shock absorber's volume, making it difficult to adapt to applications with stringent space requirements, such as the chassis space of some high-end cars or the limited installation space inside precision instruments. Summary of the Invention

[0004] To address the problem of narrow oil passages in dual-cylinder hydraulic active shock absorbers, leading to poor oil flow, this invention provides a dual-cylinder hydraulic active shock absorber, comprising:

[0005] outer cylinder;

[0006] An inner cylinder is disposed within the hollow cavity of the outer cylinder; an outer cavity is formed between the inner cylinder and the outer cylinder;

[0007] A piston unit, part of which is movably disposed within the hollow cavity of the inner cylinder, dividing it into an upper inner cavity and a lower inner cavity;

[0008] A bottom heat exchange unit is connected to the end of the inner cylinder away from the upper inner cavity; the outer peripheral wall of the bottom heat exchange unit and the inner peripheral wall of the outer cylinder are spaced apart to form a first channel;

[0009] An end cap unit is configured as a hemispherical shell; the open end of the end cap unit is connected to the end of the outer cylinder away from the upper inner cavity; the end cap unit and the bottom switching unit are spaced apart on the circumferential side to form a second channel; the end cap unit and the bottom switching unit are spaced apart on the circular end side to form a third channel.

[0010] The lower inner cavity, the bottom heat exchange unit, the third channel, the second channel, the first channel, and the outer cavity are sequentially connected to form an oil drain channel; the minimum cross-sectional area of ​​the oil drain channel is located in the first channel portion.

[0011] In some embodiments, the maximum cross-sectional area of ​​the oil drain channel is located in the second channel portion.

[0012] In some embodiments, the bottom switching unit includes a first check valve and a second check valve; the first check valve is configured to allow fluid to flow unidirectionally from the lower inner cavity to the third channel; the second check valve is configured to allow fluid to flow unidirectionally from the third channel to the lower inner cavity;

[0013] The cross-sectional area of ​​the liquid flow channel of the first check valve is smaller than the cross-sectional area of ​​the liquid flow channel of the second channel.

[0014] In some embodiments, the cross-sectional area of ​​the outer cavity is smaller than the cross-sectional area of ​​the liquid flow channel of the first one-way valve.

[0015] In some embodiments, the inner peripheral wall of the opening end of the end cap unit is connected to the outer peripheral wall of the outer cylinder.

[0016] In some embodiments, the bottom switching unit includes a first valve stem, a second valve stem, and a flow channel; the first valve stem and the second valve stem are connected at their ends away from the end cap unit; the outer diameter of the second valve stem is larger than the outer diameter of the first valve stem; the flow channel penetrates the outer periphery of the second valve stem away from the first valve stem; the third channel is at least partially composed of the flow channel; the outer peripheral wall of the first valve stem abuts against the inner peripheral wall of the inner cylinder; and the second valve stem is connected to the end of the inner cylinder away from the upper inner cavity.

[0017] In some embodiments, the dual-cylinder hydraulic active shock absorber includes a shock-absorbing assembly; the shock-absorbing assembly includes an outer cylinder unit and an inner cylinder unit; the outer cylinder unit includes a boss portion and an outer cylinder body; the boss portion is circumferentially disposed on the inner wall of the outer cylinder body.

[0018] The inner cylinder unit includes a mounting groove, a sealing ring, and the inner cylinder body; the mounting groove is arranged around the outer peripheral wall of the inner cylinder body; the sealing ring abuts against the bottom wall and the boss portion of the mounting groove respectively, so as to divide the outer cavity into an upper outer cavity and a lower outer cavity; the upper outer cavity is connected to the upper inner cavity; the lower outer cavity is connected to the first channel.

[0019] In some embodiments, the outer cylinder unit further includes a first port, a second port, and a third port; the second port communicates with the lower outer cavity; the first port and the third port communicate with the upper outer cavity;

[0020] The dual-cylinder hydraulic active shock absorber also includes a drive assembly and an energy storage assembly;

[0021] The inlet and outlet of the drive component are connected to the first port and the second port, respectively; the energy storage component is connected to the third port.

[0022] In some embodiments, the drive assembly includes a drive unit and a first support unit; the first support unit is connected to the outer cylinder and the drive unit respectively; the drive unit includes a motor and a hydraulic pump; the hydraulic pump is driven by the motor, and the inlet and outlet of the hydraulic pump are connected to the first port and the second port respectively.

[0023] In some embodiments, the energy storage assembly includes an energy storage unit and a second support unit; the inner cavity of the energy storage unit is connected to the upper outer cavity; the energy storage unit is connected to the outer peripheral wall of the outer cylinder through the second support unit; the energy storage unit and the driving unit are respectively located on opposite sides of the outer cylinder.

[0024] To address the problem of narrow oil passages in dual-cylinder hydraulic active shock absorbers, leading to poor oil flow, this invention offers the following advantages:

[0025] By changing the end cap connection position to the end of the outer cylinder away from the upper inner cavity, the end cap is no longer constrained by the internal structure of the outer cylinder. This allows it to form a second channel and a third channel with the circumferential side and the rounded end side of the bottom heat exchange unit, respectively. Simultaneously, the first channel formed by the bottom heat exchange unit and the inner circumferential wall of the outer cylinder no longer needs to be compressed to accommodate the limited space of the end cap. Compared to connecting the end cap between the outer and inner cylinders, this method creates a larger cross-sectional area for the first channel, and the overall oil flow path changes from a single narrow slit channel to multiple coordinating channels, significantly increasing the effective flow cross-sectional area and ensuring smooth and rapid oil flow within the channels. Oil can flow more quickly from the lower inner cavity through the bottom heat exchange unit, the third channel, the second channel, and the first channel into the outer cavity; or quickly through the first channel, the second channel, the third channel, and the bottom heat exchange unit into the lower inner cavity, thereby reducing the shock absorber's response delay to vibration. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a dual-cylinder hydraulic active shock absorber according to one embodiment;

[0027] Figure 2 for Figure 1 Schematic diagram of the structure of the intermediate damping component;

[0028] Figure 3 for Figure 1 Cross-sectional view of a twin-cylinder hydraulic active shock absorber;

[0029] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0030] Figure 5 for Figure 3 Enlarged view of point B in the middle;

[0031] Figure 6 for Figure 1 A schematic diagram of the structure of the driving component.

[0032] Figure label:

[0033] 10. Shock Absorption Component; 11. Outer Cylinder Unit; 111. Outer Cylinder Body; 112. Boss; 113. First Inlet; 114. Second Inlet; 115. Third Inlet; 12. Inner Cylinder Unit; 121. Inner Cylinder Body; 122. Mounting Groove; 123. Sealing Ring; 13. Piston Unit; 131. Piston Rod; 132. Piston Body; 14. Bottom Heat Exchanger Unit; 141. Bottom Heat Exchanger Module; 1411. First Valve Sill; 1412. Second Valve Sill; 1413. Flow Groove; 142. First Check Valve; 143. Second Check Valve; 15. End Cap Unit; 151. Connecting Ring; 152. Sealing Arc; 20. Drive Component; 21. Drive Unit; 211. Motor; 212. Hydraulic Pump; 22. First Support Unit; 30. Energy Storage Component; 31. Energy Storage Unit; 32. Second Support Unit. Detailed Implementation

[0034] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.

[0035] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0036] Example 1:

[0037] This embodiment proposes a dual-cylinder hydraulic active shock absorber, such as... Figure 1 , Figure 3 , Figure 4 As shown, the twin-cylinder hydraulic active shock absorber includes an outer cylinder 111, an inner cylinder 121, a piston unit 13, a bottom switching unit 14, and an end cap unit 15. The inner cylinder 121 is disposed within the hollow cavity of the outer cylinder 111. An outer cavity is formed between the inner cylinder 121 and the outer cylinder 111, providing an outer path for the storage and flow of oil.

[0038] Part of the piston unit 13 is movably disposed within the hollow cavity of the inner cylinder 121, dividing it into an upper inner cavity and a lower inner cavity. Both the upper and lower inner cavities are filled with hydraulic oil. When the carrier is vibrated, the piston unit 13 moves up and down along the inner wall of the inner cylinder 121. The smooth inner wall of the inner cylinder 121 can prevent the piston from shifting, ensuring that the piston always squeezes the oil vertically.

[0039] The bottom heat exchange unit 14 is connected to the end of the inner cylinder 121 away from the upper inner cavity. The outer peripheral wall of the bottom heat exchange unit 14 and the inner peripheral wall of the outer cylinder 111 are spaced apart to form a first channel.

[0040] The end cap unit 15 is configured as a hemispherical shell. The open end of the end cap unit 15 is connected to the end of the outer cylinder 111 away from the upper inner cavity. The end cap unit 15 and the bottom switching unit 14 are spaced apart to form a second channel on their circumferential side; the end cap unit 15 and the bottom switching unit 14 are spaced apart to form a third channel on their rounded end side. In this way, the end cap is no longer constrained by the internal structure of the outer cylinder 111, and can form the second channel and the third channel with the circumferential side and the rounded end side of the bottom switching unit 14, respectively. At the same time, the first channel formed by the bottom switching unit 14 and the inner circumferential wall of the outer cylinder 111 does not need to be compressed to accommodate the limited space of the end cap.

[0041] The lower inner cavity, bottom heat exchange unit 14, third channel, second channel, first channel, and outer cavity are sequentially connected to form an oil discharge channel. The minimum cross-sectional area of ​​the oil discharge channel is located in the first channel. This increases the narrowest part of the overall oil flow path. Compared to connecting the end cap between the outer cylinder 111 and the inner cylinder 121, the first channel has a larger cross-sectional area. Moreover, the overall oil flow path changes from a single narrow slit channel to multiple coordinated channels, significantly expanding the effective flow cross-sectional area and ensuring smooth and rapid oil flow within the channel. The oil can flow more quickly from the lower inner cavity through the bottom heat exchange unit 14, third channel, second channel, and first channel into the outer cavity; or quickly through the first channel, second channel, third channel, and bottom heat exchange unit 14 into the lower inner cavity, thereby reducing the shock absorber's response delay to vibration.

[0042] Furthermore, the maximum cross-sectional area of ​​the oil drain channel is located in the second channel. This makes the liquid flow path of the second channel wider, allowing it to adequately store high-pressure oil. This provides a more stable oil flow basis for the subsequent precise damping adjustment of the first channel, preventing untimely oil supply when the carrier experiences significant vibrations. Simultaneously, during shock absorber compression, the second channel can store more high-pressure oil, preventing the narrower first channel from bearing excessive oil pressure. This eliminates the need to increase the shock absorber's volume, enhancing pressure buffering and oil flow stabilization while further improving damping smoothness and damping adjustment accuracy.

[0043] Furthermore, the bottom switching unit 14 includes a first one-way valve 142 and a second one-way valve 143. The first one-way valve 142 is configured to allow fluid to flow unidirectionally from the lower inner cavity to the third channel; the second one-way valve 143 is configured to allow fluid to flow unidirectionally from the third channel to the lower inner cavity. The cross-sectional area of ​​the liquid flow channel of the first one-way valve 142 is smaller than that of the liquid flow channel of the second channel. Under the compression condition of the piston moving downward, the oil in the lower inner cavity needs to flow to the third channel through the first one-way valve 142, which has a smaller cross-sectional area. The small cross-sectional channel can form a moderate throttling damping, accurately control the oil flow rate, and avoid the damping force being too soft due to the oil being discharged too quickly during the compression process. At the same time, in conjunction with the second channel, it further stabilizes the pressure fluctuations in the lower inner cavity. During the recovery process as the piston moves upward, a negative pressure is formed in the lower inner cavity. The oil in the third channel can be quickly replenished through the second one-way valve 143, effectively preventing a vacuum from being generated in the lower inner cavity due to insufficient oil replenishment. This prevents cavitation from corroding the components and ensures a smooth recovery process without jamming, thereby improving the shock absorber's cushioning comfort and long-term reliability.

[0044] Furthermore, the cross-sectional area of ​​the outer cavity is smaller than the cross-sectional area of ​​the liquid flow channel of the first one-way valve 142. Since the first one-way valve 142 already has a larger flow cross-sectional area, it ensures efficient flow of oil from the lower inner cavity to the third channel under compression conditions. Therefore, there is no need to enlarge the outer cavity oil passage to compensate for the flow rate, avoiding an increase in volume due to oil passage expansion. Thus, without affecting the oil flow efficiency, by compressing the radial space of the outer cavity, the overall volume of the shock absorber can be reduced, making it more suitable for compact installation scenarios.

[0045] Furthermore, the inner peripheral wall of the open end of the end cap unit 15 is connected to the outer peripheral wall of the outer cylinder 111. In this way, the end cap unit 15, with its inner peripheral wall connected to the outer peripheral wall of the outer cylinder 111, only acts on the outer circumferential area of ​​the outer cylinder, and will not extend into the interior of the outer cylinder 111 or the annular oil passage between the inner cylinder 121 and the outer cylinder 111. This indirectly widens the oil drain channel, eliminating the need to increase the volume of the shock absorber to enlarge the oil passage. Moreover, this facilitates the installation of the end cap unit 15 during assembly.

[0046] In some embodiments, the end cap unit 15 includes a connecting ring 151 and a sealing arc portion 152. The sealing arc portion 152 seals one end of the connecting ring 151, and the connecting ring 151 and the sealing arc portion 152, when combined, form a hemispherical shell shape. The inner peripheral wall of the connecting ring 151 is welded and fixed to the outer peripheral wall of the outer cylinder 111. In this way, the connecting ring 151 only acts on the outside of the outer cylinder 111, completely avoiding the oil passage and completely eliminating the end cap from obstructing the oil passage. The welded fixing has high strength and can resist the vibration and impact during the operation of the shock absorber, improving the overall structural stability. At the same time, the sealing arc portion 152 can effectively block oil leakage from the end, taking into account both the unobstructed oil passage and the reliability of the seal.

[0047] Further, the bottom switching unit 14 includes a bottom switching module 141. The bottom switching module 141 includes a first valve stem 1411, a second valve stem 1412, and a flow channel 1413. The first valve stem 1411 and the second valve stem 1412 are connected at their ends away from the end cap unit 15. The outer diameter of the second valve stem 1412 is larger than the outer diameter of the first valve stem 1411. The flow channel 1413 penetrates the outer periphery of the second valve stem 1412 away from the first valve stem 1411. The third channel is at least partially formed by the flow channel 1413. The outer peripheral wall of the first valve stem 1411 abuts against the inner peripheral wall of the inner cylinder 121. The second valve stem 1412 is connected to the end of the inner cylinder 121 away from the upper inner cavity. The second valve stem 1412 has a larger outer diameter and can directly form a radial limiting and sealing fit with the end of the inner cylinder 121 away from the upper inner cavity. The first valve stem 1411 has a smaller outer diameter and abuts against the inner wall of the inner cylinder. The two work together to form a double positioning system. Without the need for additional complex fixing structures, the bottom replacement unit 14 can be quickly and stably assembled at the bottom of the inner cylinder, avoiding shaking and displacement during operation.

[0048] The flow groove 1413 is opened on the outer periphery of the second valve column 1412 and forms a third channel. The second valve column 1412 is connected to the end of the inner cylinder, and the first valve column 1411 abuts against the inner wall of the inner cylinder. Both avoid the area of ​​the flow groove 1413, which can ensure that the oil flows smoothly into and out of the third channel along the flow groove 1413 and is not blocked by the fixed structure.

[0049] Furthermore, such as Figure 5As shown, the dual-cylinder hydraulic active shock absorber includes a shock-absorbing assembly 10. The shock-absorbing assembly 10 includes an outer cylinder unit 11 and an inner cylinder unit 12. The outer cylinder unit 11 includes a boss portion 112 and an outer cylinder body 111. The boss portion 112 is circumferentially disposed on the inner wall of the outer cylinder body 111. The inner cylinder unit 12 includes a mounting groove 122, a sealing ring 123, and an inner cylinder body 121. The mounting groove 122 is circumferentially disposed on the outer peripheral wall of the inner cylinder body 121. The sealing ring 123 abuts against the bottom wall of the mounting groove 122 and the boss portion 112 respectively, dividing the outer cavity into an upper outer cavity and a lower outer cavity. The upper outer cavity communicates with the upper inner cavity. The lower outer cavity communicates with the first channel. The boss 112 and the sealing ring 123 in the mounting groove 122 form a precise abutment. The radial clamping force of the boss 112 on the sealing ring 123 can reliably isolate the upper and lower outer cavities, preventing fluid cross-flow between the two chambers. This ensures that the drive unit 21 can accurately and effectively regulate the flow rate of the upper and lower cavities through the first port 113 and the second port 114, fundamentally guaranteeing the accuracy of damping force adjustment. Simultaneously, it can limit the axial movement of the inner cylinder within the outer cylinder 111. Combined with the elastic contact of the sealing ring 123, it can compensate for minor dimensional deviations between the outer and inner cylinders during processing or assembly, ensuring sealing reliability while avoiding structural wear caused by rigid contact. Furthermore, the sealing ring 123 is constrained within the mounting groove 122 and stably abuts against the boss 112, preventing displacement or overturning of the sealing ring 123 under high-pressure fluid impact or relative movement of the inner cylinder. This extends the service life of the sealing ring 123 and reduces the degradation of damping performance due to seal failure.

[0050] Furthermore, such as Figure 2 The outer cylinder unit 11 shown also includes a first port 113, a second port 114, and a third port 115. The second port 114 communicates with the lower outer cavity. The first port 113 and the third port 115 communicate with the upper outer cavity. The twin-cylinder hydraulic active shock absorber also includes a drive assembly 20 and an energy storage assembly 30. The inlet and outlet of the drive assembly 20 are respectively connected to the first port 113 and the second port 114. The energy storage assembly 30 is connected to the third port 115.

[0051] When the damper needs increased damping, the drive assembly 20 can pump oil into the lower outer cavity through the first port 113 to increase the pressure, or limit the flow of oil through the second port 114 to reduce the outflow of oil, thereby changing the motion resistance of the inner cylinder unit 12. When the damping needs to be reduced, the drive assembly 20 reverses the oil flow.

[0052] When the shock absorber is in compression mode, the piston moves downward, the volume of the upper inner cavity increases and the volume of the lower inner cavity decreases. The oil in the lower inner cavity flows into the upper inner cavity through the oil discharge channel. The upper outer cavity needs to be replenished with oil due to the increase in volume. The energy storage component 30 can release oil through the third port 115 to replenish the upper inner cavity, avoiding oil circuit cavitation caused by low pressure.

[0053] When the shock absorber returns to its original operating condition, the piston moves upward, the volume of the upper inner cavity decreases, and the energy storage component 30 can absorb excess oil and pressure in the upper outer cavity through the third port 115 to prevent the pressure from rising suddenly and damaging the seals or affecting the damping adjustment accuracy.

[0054] When the oil in the inner cavity is squeezed into the lower outer cavity, the pressure in the upper outer cavity may increase due to the displacement of the piston unit 13. The energy storage component 30 can absorb the excess oil and pressure in the upper outer cavity through the third port 115 to prevent the pressure from rising suddenly and damaging the seals or affecting the damping adjustment accuracy.

[0055] Furthermore, such as Figure 6 As shown, the drive assembly 20 includes a drive unit 21 and a first support unit 22. The first support unit 22 is connected to both the outer cylinder 111 and the drive unit 21. The drive unit 21 includes a motor 211 and a hydraulic pump 212. The hydraulic pump 212 is driven by the motor 211, and its inlet and outlet ports are connected to a first port 113 and a second port 114, respectively.

[0056] The drive unit 21 actively adjusts the flow rate, pressure, or direction of the fluid based on the vibration signal fed back by the sensor. This is done by increasing the fluid flow resistance to enhance damping and suppress severe vibrations, or by reducing the resistance to enhance the buffering effect, thereby adjusting the vibration damping performance in real time.

[0057] Driven by motor 211, the oil flow rate of hydraulic pump 212 can be adjusted in real time. By changing the flow rate, the pressure difference in the chamber is changed, thereby dynamically adjusting the damping force of piston movement. This achieves continuous stepless adjustment of the damping force from minimum to maximum, rather than the fixed damping or graded damping of a passive shock absorber. It can accurately match the shock absorption requirements under different dynamic conditions such as vehicle acceleration, braking, steering, and bumps.

[0058] Furthermore, the energy storage assembly 30 includes an energy storage unit 31 and a second support unit 32. The inner cavity of the energy storage unit 31 is connected to the upper outer cavity. The energy storage unit 31 is connected to the outer peripheral wall of the outer cylinder 111 through the second support unit 32. The energy storage unit 31 and the drive unit 21 are located on opposite sides of the outer cylinder 111.

[0059] When the piston moves upward, the volume of the upper inner cavity decreases, and the volume of the upper outer cavity changes accordingly. The energy storage unit 31 can absorb excess fluid through its own elastic contraction. When the piston moves downward, the volume of the upper inner cavity increases, and the energy storage unit 31 releases fluid to replenish it, avoiding drastic fluctuations in chamber pressure due to sudden volume changes. This provides a stable fluid environment for the drive unit 21 to accurately adjust the damping force, ensuring smooth damping response. The drive unit 21 and the energy storage unit 31 are located on opposite sides of the outer cylinder 111, allowing the overall center of gravity of the shock absorber to be as close as possible to the axis of the outer cylinder 111, preventing the center of gravity from shifting to one side. This balanced design significantly reduces the eccentric torque during shock absorber operation.

[0060] In some embodiments, the piston unit 13 includes a piston rod 131 and a piston body 132. The piston body 132 is disposed within the hollow cavity of the inner cylinder 121, dividing it into an upper inner cavity and a lower inner cavity. The piston rod 131 is movably connected to the piston body 132. Under the pressure adjustment action of the drive unit 21, the piston body 132 drives the piston rod 131 to partially extend outside the outer cylinder 111 or partially retract into the inner cylinder 121. When the active shock absorber is installed in a vehicle, the piston body 132 can increase the support stiffness or increase the buffer stroke by moving, thereby improving driving and riding comfort.

[0061] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes can be made in form and detail without departing from the scope of this disclosure.

Claims

1. A dual-cylinder hydraulic active shock absorber, characterized in that, The dual-cylinder hydraulic active shock absorber includes: outer cylinder; An inner cylinder is disposed within the hollow cavity of the outer cylinder; an outer cavity is formed between the inner cylinder and the outer cylinder; A piston unit, part of which is movably disposed within the hollow cavity of the inner cylinder, dividing it into an upper inner cavity and a lower inner cavity; A bottom heat exchange unit is connected to the end of the inner cylinder away from the upper inner cavity; the outer peripheral wall of the bottom heat exchange unit and the inner peripheral wall of the outer cylinder are spaced apart to form a first channel; An end cap unit is configured as a hemispherical shell; the open end of the end cap unit is connected to the end of the outer cylinder away from the upper inner cavity; the end cap unit and the bottom switching unit are spaced apart on the circumferential side to form a second channel; the end cap unit and the bottom switching unit are spaced apart on the circular end side to form a third channel. The lower inner cavity, the bottom heat exchange unit, the third channel, the second channel, the first channel, and the outer cavity are sequentially connected to form an oil drain channel; the minimum cross-sectional area of ​​the oil drain channel is located in the first channel portion; The maximum cross-sectional area of ​​the oil drain channel is located in the second channel portion.

2. The dual-cylinder hydraulic active shock absorber according to claim 1, characterized in that, The bottom switching unit includes a first check valve and a second check valve; the first check valve is configured to allow fluid to flow unidirectionally from the lower inner cavity to the third channel; the second check valve is configured to allow fluid to flow unidirectionally from the third channel to the lower inner cavity; The cross-sectional area of ​​the liquid flow channel of the first check valve is smaller than the cross-sectional area of ​​the liquid flow channel of the second channel.

3. A twin-cylinder hydraulic active shock absorber according to claim 2, characterized in that, The cross-sectional area of ​​the outer cavity is smaller than the cross-sectional area of ​​the liquid flow channel of the first one-way valve.

4. A dual-cylinder hydraulic active shock absorber according to claim 1, characterized in that, The inner peripheral wall of the opening end of the end cap unit is connected to the outer peripheral wall of the outer cylinder.

5. A twin-cylinder hydraulic active shock absorber according to claim 1, characterized in that, The bottom switching unit includes a first valve stem, a second valve stem, and a flow groove; the first valve stem and the second valve stem are connected at their ends away from the end cap unit; the outer diameter of the second valve stem is larger than the outer diameter of the first valve stem; the flow groove passes through the outer periphery of the second valve stem away from the first valve stem; the third channel is at least partially composed of the flow groove; the outer peripheral wall of the first valve stem abuts against the inner peripheral wall of the inner cylinder; the second valve stem is connected to the end of the inner cylinder away from the upper inner cavity.

6. A twin-cylinder hydraulic active shock absorber according to claim 5, characterized in that, The dual-cylinder hydraulic active shock absorber includes a shock-absorbing assembly; the shock-absorbing assembly includes an outer cylinder unit and an inner cylinder unit; the outer cylinder unit includes a boss portion and an outer cylinder body; the boss portion is circumferentially disposed on the inner wall of the outer cylinder body; The inner cylinder unit includes a mounting groove, a sealing ring, and the inner cylinder body; the mounting groove is arranged around the outer peripheral wall of the inner cylinder body; the sealing ring abuts against the bottom wall and the boss portion of the mounting groove respectively, so as to divide the outer cavity into an upper outer cavity and a lower outer cavity; the upper outer cavity is connected to the upper inner cavity; the lower outer cavity is connected to the first channel.

7. A twin-cylinder hydraulic active shock absorber according to claim 6, characterized in that, The outer cylinder unit further includes a first port, a second port, and a third port; the second port is connected to the lower outer cavity; the first port and the third port are connected to the upper outer cavity; The dual-cylinder hydraulic active shock absorber also includes a drive assembly and an energy storage assembly; The inlet and outlet of the drive component are connected to the first port and the second port, respectively; the energy storage component is connected to the third port.

8. A twin-cylinder hydraulic active shock absorber according to claim 7, characterized in that, The drive assembly includes a drive unit and a first support unit; the first support unit is connected to the outer cylinder and the drive unit respectively; the drive unit includes a motor and a hydraulic pump; the hydraulic pump is driven by the motor, and the inlet and outlet of the hydraulic pump are connected to the first port and the second port respectively.

9. A twin-cylinder hydraulic active shock absorber according to claim 8, characterized in that, The energy storage assembly includes an energy storage unit and a second support unit; the inner cavity of the energy storage unit is connected to the upper outer cavity; the energy storage unit is connected to the outer peripheral wall of the outer cylinder through the second support unit; the energy storage unit and the drive unit are located on opposite sides of the outer cylinder.

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