A high-pressure large-flow oil cylinder system with prolonged maintenance period

Abstract

This invention relates to the technical field of hydraulic cylinder systems, and particularly to a high-pressure, high-flow hydraulic cylinder system that extends maintenance cycles. The system includes a cylinder body, a piston body, and a piston rod. Connectors one and two, communicating with the piston cavity, are installed on the side wall of the cylinder body. It also includes a movable sealing ring and a floating structure. The movable sealing ring is annular and can expand and contract radially. It is concentrically mounted on the piston body, with its outer surface sliding in contact with the inner wall of the cylinder body. The floating structure is concentrically mounted on the piston body and moves axially along the piston body under the pressure of hydraulic oil. The floating structure presses outward against the inner wall of the movable sealing ring, causing it to expand. The pressure between the expanded movable sealing ring and the inner wall of the cylinder body changes synchronously with the pressure of the hydraulic oil. By employing a floating structure and a movable sealing ring, a positive correlation and adaptive relationship between the sealing force and the hydraulic oil pressure are achieved, increasing sealing reliability and extending the maintenance cycle of the hydraulic cylinder system.

Description

Technical Field

[0001] This invention relates to the technical field of hydraulic cylinder systems, and in particular to a high-pressure, high-flow hydraulic cylinder system with extended maintenance cycles. Background Technology

[0002] High-pressure, high-flow hydraulic cylinder systems require stable operation over long periods, and regular maintenance can cause these systems to temporarily malfunction. Therefore, hydraulic cylinder systems with longer maintenance cycles have a greater advantage.

[0003] Currently, common technical approaches to extending maintenance cycles include improving the reliability of seals, purifying hydraulic oil, and using self-cleaning filters. Existing technologies have disclosed various hydraulic cylinder systems with extended maintenance cycles that employ techniques to improve the reliability of seals. For example, the dynamic balancing sealing method proposed in Chinese invention patent application CN118728961A includes step one: structural configuration. A spacer ring is installed between the first and second seals, and a hydraulic cylinder is installed with a dynamic balancing piston ring inside. The hydraulic cylinder is connected to the space between the medium and the seals via oil pipes. The hydraulic cylinder, dynamic balancing piston ring, and oil pipes are located outside the sealing duct and are concentric with it. Using the dynamic balancing piston ring and hydraulic cylinder structure can effectively balance medium pressure fluctuations, ensuring equal pressure at both ends of the first seal. This helps eliminate pressure differentials and prevents solid particles from intruding into the space between the seals, thereby improving the service life and stability of the seals.

[0004] Because the sealing pressure between the seal and the inner wall of the cylinder is fixed and cannot adapt to changes in hydraulic oil pressure, the sealing pressure between the traditional seal and the inner wall of the cylinder is usually high in order to adapt to high-pressure conditions. This results in greater wear under low-pressure and high-flow conditions. After the seal wears, its sealing effect naturally decreases and cannot be adaptively compensated, leading to seal failure under high-pressure and high-flow conditions, which is not conducive to extending the maintenance cycle of the hydraulic cylinder system. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention provides a high-pressure, high-flow hydraulic cylinder system that adopts a floating structure and a movable sealing ring, realizes positive correlation and adaptive behavior between sealing force and hydraulic oil pressure, increases sealing reliability, and extends the maintenance cycle of the hydraulic cylinder system.

[0006] This invention discloses a high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles, comprising a cylinder body, an internal piston chamber, a piston body slidably mounted within the piston chamber, a fixed sealing ring on the outer wall of the piston body to seal the piston body and the inner wall of the cylinder body, a piston rod mounted on the piston body, the end of the piston rod extending outward through a seal at the end of the cylinder body, and two connectors, a first connector and a second connector, communicating with the piston chamber, mounted on the side wall of the cylinder body, respectively located on opposite sides of the piston body; the system also includes a movable sealing ring and a floating structure, the movable sealing ring being annular and capable of radial expansion and contraction, and concentrically mounted on the piston body. On the piston body, the outer surface of the movable sealing ring slides in contact with the inner wall of the cylinder. The floating structure is concentrically mounted on the piston body. Under the pressure of hydraulic oil, the floating structure moves axially along the piston body. The floating structure presses outward against the inner wall of the movable sealing ring, causing the movable sealing ring to expand. After the movable sealing ring expands, the pressure between it and the inner wall of the cylinder changes synchronously with the pressure of the hydraulic oil. Connectors one and two are connected to an external hydraulic oil delivery system. When hydraulic oil enters the piston chamber of the cylinder through connector one and exits through connector two, the piston body and piston rod move towards connector two. Similarly, hydraulic oil enters the piston chamber of the cylinder through connector two and exits through connector two. When the connector is discharged, the piston body and piston rod move towards the connector, enabling the hydraulic cylinder system to operate. During operation, the fixed sealing ring between the piston body and the inner wall of the cylinder provides a fixed basic sealing performance. Simultaneously, under the pressure of hydraulic oil, the floating structure moves closer to the piston body along its axial direction, causing the floating structure to squeeze the inner wall of the movable sealing ring from the inside out. This causes the movable sealing ring to expand radially. After the movable sealing ring expands, the sealing pressure between its outer surface and the inner wall of the cylinder increases. The greater the hydraulic oil pressure, the greater the internal squeezing force of the floating structure on the movable sealing ring, further increasing the expansion of the movable sealing ring. The larger the expansion size, the greater the sealing pressure between the outer surface of the movable sealing ring and the inner wall of the cylinder. This achieves self-adaptation between the sealing effect of the movable sealing ring and the hydraulic oil pressure. This allows for setting a smaller initial sealing pressure between the movable sealing ring and the inner wall of the cylinder, achieving stable operation and reduced wear under low-pressure conditions, and preventing sealing failure under high-pressure conditions. It realizes a positive correlation and self-adaptation between sealing force and hydraulic oil pressure. Furthermore, when the wear of the movable sealing ring is within the set range, its expansion can adaptively compensate for the wear, thereby ensuring that the sealing performance does not decline, increasing sealing reliability, and extending the maintenance cycle of the cylinder system.

[0007] Preferably, the floating structure includes a short rod and a push ring 1. Two movable sealing rings are provided, which are concentrically mounted on the upper and lower end faces of the piston body, respectively. The short rod is concentrically mounted on the lower end face of the piston body. The two push ring 1s are slidably fitted onto the short rod and the piston rod, respectively. The push ring 1s are annular and are located on the upper and lower sides of the two movable sealing rings, respectively. Fixed sealing rings that seal against the inner wall of the cylinder are installed on the outer circular surface of the two push ring 1s, and fixed sealing rings that seal against the short rod and the piston rod are installed on the inner circular surface of the two push ring 1s, respectively. Spring 1s are installed on the ends of the two push ring 1s facing the piston body, and the other ends of the two spring 1s are connected to the upper and lower end faces of the piston body, respectively. A pressing part is provided on the end face of the push ring 1 facing the movable sealing ring. A pressure-bearing part matching the pressing part of the push ring 1 is provided on the inner wall of the two movable sealing rings. The pressing part presses against the pressure-bearing part, causing the movable sealing ring to expand radially outward.

[0008] Preferably, it also includes two spring seats, which are respectively mounted on the end faces of the two push rings and the movable sealing ring by multiple screws, and the two springs are respectively mounted on the two spring seats.

[0009] Preferably, it also includes two filler nozzles, and each of the two push rings has a through-hole for filling oil, and two filler nozzles are installed on the oil filling holes of the two push rings respectively.

[0010] Preferably, it also includes two retaining rings, which are respectively installed on two push rings. Each retaining ring is provided with a high-density sponge ring, which is used to clean the inner wall of the cylinder.

[0011] Preferably, the piston body includes a lower cover plate and an upper cover plate, which are installed at the lower end of the piston rod. A mounting cavity is provided between the lower and upper cover plates. A fixed sealing ring is provided on the outer surface of both the lower and upper cover plates to seal against the inner wall of the cylinder. An oil passage hole is provided on both the lower and upper cover plates. Two movable sealing rings are provided, concentrically mounted on opposite end faces of the lower and upper cover plates. The oil passage hole is located inside the two movable sealing rings and close to the piston rod. The floating structure includes a second push ring, which is located on the inner side of the two movable sealing rings and close to the piston rod. Between the sealing rings, push ring two is slidably sleeved on the piston rod. The outer surface of push ring two is provided with a fixed sealing ring five that seals against the inner wall of the cylinder. The inner wall of push ring two is provided with a fixed sealing ring six that seals against the piston rod. Both the upper and lower ends of push ring two are provided with extrusion parts. The inner walls of the two movable sealing rings are provided with pressure-bearing parts that match the two extrusion parts of push ring two. The extrusion parts extrude the pressure-bearing parts, causing the movable sealing rings to expand radially outward. Both the upper and lower ends of push ring two are installed with spring two. The other ends of the two spring two are connected to the lower cover plate and the upper cover plate, respectively.

[0012] Preferably, the oil perforations on the lower and upper cover plates are circular, circular groove-shaped, or arc-shaped.

[0013] Preferably, the extrusion part is a chamfer one of an annular structure concentrically arranged on one end face of the push ring, and the pressure bearing part is a chamfer two provided on the inner wall edge of the movable sealing ring, with chamfer two matching and sliding contact with chamfer one.

[0014] Preferably, the movable sealing ring includes an elastic support layer and an elastic friction layer. The inner surface of the elastic support layer has a chamfered edge, and the outer surface of the elastic support layer has an arc-shaped groove. The elastic friction layer is fitted onto the outer arc-shaped groove of the elastic support layer.

[0015] Preferably, the elastic support layer is nitrile rubber, hydrogenated nitrile rubber, or a metal skeleton; the elastic friction layer is polytetrafluoroethylene, polyurethane, or polyetheretherketone.

[0016] Compared with the prior art, the beneficial effects of the present invention are: to achieve stable operation and reduced wear under low pressure conditions, and to achieve the effect of sealing without failure under high pressure conditions; to achieve positive correlation and adaptive adaptation between sealing force and hydraulic oil pressure; and to ensure that the wear of the movable sealing ring is within the set range, its expansion can adaptively compensate for the wear, thereby ensuring that the sealing performance does not decline, thereby increasing the sealing reliability and extending the maintenance cycle of the cylinder system. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall partial cross-sectional structure of Embodiment 1 of the present invention; Figure 2 This is an isometric structural diagram of the floating structure and movable sealing ring, etc., of Embodiment 1 of the present invention; Figure 3 This is a partial cross-sectional view of the floating structure and movable sealing ring, etc., of Embodiment 1 of the present invention. Figure 4 This is a structural diagram showing the exploded state of the floating structure and movable sealing ring, etc., of Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the overall partial cross-sectional structure of Embodiment 2 of the present invention; Figure 6 This is an isometric structural diagram of the floating structure and movable sealing ring, etc., of Embodiment 2 of the present invention; Figure 7 This is a partial cross-sectional view of the floating structure and movable sealing ring, etc., of Embodiment 2 of the present invention; Figure 8 This is a structural diagram showing the exploded state of the floating structure and movable sealing ring, etc., of Embodiment 1 of the present invention; Figure 9 This is a partial cross-sectional view of the movable sealing ring.

[0018] The following are labels in the attached diagram: 1. Cylinder body; 2. Connector 1; 3. Connector 2; 4. Piston body; 5. Piston rod; 6. Movable sealing ring; 7. Fixed sealing ring; 8. Push ring 1; 9. Spring 1; 10. Spring seat ring; 11. Screw; 12. Oil nozzle; 13. Retaining ring; 14. High-density sponge ring; 15. Lower cover plate; 16. Upper cover plate; 17. Push ring 2; 18. Spring 2; 19. Elastic support layer; 20. Elastic friction layer; 21. Short rod. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0020] Example 1, as Figure 1 , Figure 5 and Figure 9 As shown, a high-pressure, high-flow hydraulic cylinder system with extended maintenance cycles includes a cylinder body 1. A piston chamber is provided inside the cylinder body 1, and a piston body 4 is slidably mounted in the piston chamber. A fixing seal ring 7 is provided on the outer wall of the piston body 4, sealing the piston body 4 and the inner wall of the cylinder body 1. A piston rod 5 is mounted on the piston body 4, with its end passing through a seal at the end of the cylinder body 1 and extending to the outside. Connectors 1-2 and 2-3, communicating with the piston chamber, are installed on the side wall of the cylinder body 1, respectively located on both sides of the piston body 4. It also includes a movable sealing ring 6 and a floating structure. The movable sealing ring 6 is annular and can expand and contract radially. The movable sealing ring 6 is concentrically mounted on the piston body 4. The outer surface of the movable sealing ring 6 slides in contact with the inner wall of the cylinder body 1. The floating structure is concentrically mounted on the piston body 4. Under the pressure of hydraulic oil, the floating structure moves axially along the piston body 4. The floating structure presses the inner wall of the movable sealing ring 6 outward, causing the movable sealing ring 6 to expand. After the movable sealing ring 6 expands, the pressure between it and the inner wall of the cylinder body 1 changes synchronously with the pressure of the hydraulic oil.

[0021] The end face on the piston body 4 where the piston rod 5 is mounted is designated as the upper end face, and the end face on the piston body 4 facing away from the piston rod 5 is designated as the lower end face.

[0022] The movable sealing ring 6 includes an elastic support layer 19 and an elastic friction layer 20. The inner surface of the elastic support layer 19 has a chamfered edge, and the outer surface of the elastic support layer 19 has an arc groove. The elastic friction layer 20 is fitted onto the outer arc groove of the elastic support layer 19.

[0023] It is important to understand that connector 2 and connector 3 are connected to an external hydraulic oil delivery system. When hydraulic oil enters the piston chamber of cylinder 1 through connector 2 and exits through connector 3, the piston body 4 and piston rod 5 move towards connector 3. Similarly, when hydraulic oil enters the piston chamber of cylinder 1 through connector 2 and exits through connector 2, the piston body 4 and piston rod 5 move towards connector 2, thus enabling the operation of the hydraulic cylinder system.

[0024] The elastic support layer 19 is used to elastically support the elastic friction layer 20. The arc-shaped groove structure makes the connection between the elastic friction layer 20 and the elastic support layer 19 more secure and improves reliability. The elastic support layer 19 is made of nitrile rubber, hydrogenated nitrile rubber or elastic metal skeleton, and the elastic friction layer 20 is made of polytetrafluoroethylene, polyurethane or polyetheretherketone. The actual configuration is reasonably adjusted and combined according to the actual working conditions.

[0025] As an alternative, the elastic support layer 19 can also be made of silicone rubber or fluororubber to accommodate a wider temperature range. In addition, the interfaces of exposed moving parts such as joint 1 2 and joint 2 3 are equipped with sealing gaskets to prevent hydraulic oil leakage. The end of the cylinder body 1 and the penetration point of the piston rod 5 are equipped with high-pressure resistant sealing rings and filled with high-temperature resistant sealing grease. The sliding mating surfaces of the piston body 4 and the inner wall of the cylinder body 1 are equipped with wear-resistant guide rings (not shown in the figure) to reduce friction and ensure smooth sliding over a long period of time. High-wear parts such as the fixed sealing ring 7 and the movable sealing ring 6 adopt a detachable snap-fit ​​structure for easy replacement after wear. During long-term operation, the heat generated by the high-pressure hydraulic oil is dissipated through the heat dissipation fins on the outer wall of the cylinder body 1. Electrical components such as the controllers of external hydraulic pumps and sensors are all encapsulated in a waterproof and dustproof control box with a protection level of not less than IP55.

[0026] During operation, the fixed sealing ring 7 between the piston body 4 and the inner wall of the cylinder 1 provides a fixed basic sealing performance. Simultaneously, under the pressure of hydraulic oil, the floating structure moves axially towards the piston body 4, causing it to press against the inner wall of the movable sealing ring 6 from the inside out. This causes the movable sealing ring 6 to expand radially. After expansion, the sealing pressure between the outer surface of the movable sealing ring 6 and the inner wall of the cylinder 1 increases. Furthermore, the greater the hydraulic oil pressure, the greater the internal compressive force of the floating structure on the movable sealing ring 6, resulting in a larger expansion dimension of the movable sealing ring 6, i.e., the larger the outer surface of the movable sealing ring 6. The greater the sealing pressure on the inner wall of cylinder 1, the more adaptive the sealing effect of the movable sealing ring 6 is to the hydraulic oil pressure. The initial sealing pressure between the movable sealing ring 6 and the inner wall of cylinder 1 can be set to be relatively small, achieving stable operation and reduced wear under low-pressure conditions, while ensuring that the seal does not fail under high-pressure conditions. This achieves a positive correlation and adaptive relationship between the sealing force and the hydraulic oil pressure. Furthermore, when the wear of the movable sealing ring 6 is within the set range, its expansion can adaptively compensate for the aforementioned wear, thereby ensuring that the sealing performance does not decline. This increases the sealing reliability and extends the maintenance cycle of the cylinder system.

[0027] Example 2, as Figures 1 to 4 As shown, based on Embodiment 1, the floating structure includes a short rod 21 and a push ring 8. Two movable sealing rings 6 are provided, and the two movable sealing rings 6 are concentrically mounted on the upper and lower end faces of the piston body 4, respectively. The short rod 21 is concentrically mounted on the lower end face of the piston body 4. The two push rings 8 are slidably fitted on the short rod 21 and the piston rod 5, respectively. The push rings 8 are annular, and the two push rings 8 are located on the upper and lower sides of the two movable sealing rings 6, respectively. Springs 9 are installed on the ends of the two push rings 8 facing the piston body 4, and the other ends of the two springs 9 are connected to the upper and lower end faces of the piston body 4, respectively. A pressing part is provided on the end face of the push ring 8 facing the movable sealing ring 6. The inner wall of the two movable sealing rings 6 is provided with a pressure-bearing part that matches the pressing part of the push ring 8. The pressing part presses the pressure-bearing part, causing the movable sealing ring 6 to expand radially outward.

[0028] It also includes two filler nozzles 12, and each of the two push rings 8 has a through-hole for filling oil, with two filler nozzles 12 installed on each of the two filling holes.

[0029] Both the upper and lower end faces of the piston body 4 are provided with concentric annular grooves. Both the end faces of the two movable sealing rings 6 facing the piston body 4 are provided with annular elastic retaining rings, and the elastic retaining rings are respectively fitted and locked in the two annular grooves, so as to realize the movable installation of the two movable sealing rings 6 with the upper and lower end faces of the piston body 4. Preferably, the width of the annular groove is greater than the width of the elastic retaining ring, and the cross-section of the annular groove and the elastic retaining ring are both dovetail-shaped. The dovetail structure ensures that the movable sealing rings 6 will not detach from the piston body 4.

[0030] Two fixed sealing rings are installed on the outer surfaces of the two push rings 8 to seal against the inner wall of the cylinder 1. Two fixed sealing rings are installed on the inner surfaces of the two push rings 8 to seal against the short rod 21 and the piston rod 5, respectively, to ensure that a sealed cavity is formed between the push rings 8 and the piston body 4. The elastic force of the two springs 9 pulls the two push rings 8 toward the piston body 4, thereby creating a certain initial pressure on the two movable sealing rings 6. Two oil fillers 12 and two oil injection holes are connected to the two sealed cavities between the two push rings 8 and the piston body 4, respectively. High-pressure lubricating oil is injected into the two sealed cavities through the two oil fillers 12 to lubricate the movable sealing rings 6 and reduce the wear of the two movable sealing rings 6.

[0031] Fixed sealing rings two and three are made of the same material as fixed sealing ring 7, but have different specifications and models, in order to simplify design and assembly.

[0032] When hydraulic oil is input into cylinder 1, the pressure of the hydraulic oil acts on a push ring-8 and is transmitted to the piston body 4, causing the piston body 4 and piston rod 5 to move. At the same time, the push ring-8 compresses the spring-9 and squeezes the pressure-bearing part of the movable sealing ring 6 through the extrusion part, causing the movable sealing ring 6 to expand radially outward. This causes the sealing pressure between the outer surface of the movable sealing ring 6 and the inner wall of cylinder 1 to increase adaptively. When the input hydraulic oil pressure decreases, the spring-9 pushes the push ring-8 to move adaptively, thereby reducing the extrusion force on the movable sealing ring 6 and causing the sealing pressure between the outer surface of the movable sealing ring 6 and the inner wall of cylinder 1 to decrease adaptively.

[0033] The extrusion part is a chamfer one of an annular structure concentrically arranged on the end face of the push ring 8, and the pressure bearing part is a chamfer two set on the inner wall edge of the movable sealing ring 6. The chamfer two matches and slides in contact with the chamfer one, and the angle of the chamfer one is preferably 35 degrees.

[0034] It also includes two spring seats 10, which are respectively mounted on the end faces of the two push rings 8 and the movable sealing rings 6 via multiple screws 11. Two springs 9 are respectively mounted on the two spring seats 10. By rotating the multiple screws 11, the distance between the two spring seats 10 and the two push rings 8 is adjusted, thereby adjusting the initial pressure of the two springs 9, and then adjusting the initial extrusion pressure of the two push rings 8 on the two movable sealing rings 6, thereby adjusting the initial sealing pressure between the outer wall surface of the two movable sealing rings 6 and the inner wall of the cylinder body 1 to adapt to different pressure conditions of the oil cylinder.

[0035] It also includes two retaining rings 13, which are respectively installed on two push rings 8. Each retaining ring 13 is provided with a high-density sponge ring 14. The two high-density sponge rings 14 scrape the inner wall of the cylinder body 1. The two retaining rings 13 are preferably detachably installed on the two push rings 8 by bolts. When the cylinder is running, the two retaining rings 13 drive the two high-density sponge rings 14 to move, so that the two high-density sponge rings 14 scrape and clean the inner wall of the cylinder body 1, thereby wiping away and adsorbing the attached debris, reducing the wear of debris on the movable sealing ring 6 and the fixed sealing ring 7.

[0036] As an alternative, spring 9 can also be replaced with a gas spring or a hydraulic damper to provide a more stable initial pressure; in addition, the high-density sponge ring 14 is a detachable snap-fit ​​installation, which is convenient for replacement during maintenance.

[0037] Example 3, as Figures 5 to 8 As shown, based on Embodiment 1, the piston body 4 includes a lower cover plate 15 and an upper cover plate 16. The lower cover plate 15 and the upper cover plate 16 are installed at the lower end of the piston rod 5. An installation cavity is provided between the lower cover plate 15 and the upper cover plate 16. The outer surfaces of the lower cover plate 15 and the upper cover plate 16 are provided with fixed sealing rings 4 that are in sealing contact with the inner wall of the cylinder body 1. The lower cover plate 15 and the upper cover plate 16 are provided with oil passage holes. Two movable sealing rings 6 are provided. The two movable sealing rings 6 are respectively concentrically and movably installed on the opposite end faces of the lower cover plate 15 and the upper cover plate 16. The oil passage holes are located inside the two movable sealing rings 6 and arranged close to the piston rod 5.

[0038] The floating structure includes a second push ring 17, which is located between the movable sealing rings 6. The second push ring 17 is slidably sleeved on the piston rod 5. The outer surface of the second push ring 17 is provided with a fixed sealing ring 5 that seals against the inner wall of the cylinder 1. The inner wall of the second push ring 17 is provided with a fixed sealing ring 6 that seals against the piston rod 5. The upper and lower ends of the second push ring 17 are provided with extrusion parts. The inner walls of the two movable sealing rings 6 are provided with pressure-bearing parts that match the two extrusion parts of the second push ring 17. The extrusion parts extrude the pressure-bearing parts, causing the movable sealing rings 6 to expand radially outward. The upper and lower ends of the second push ring 17 are each equipped with a second spring 18. The other ends of the two second springs 18 are connected to the lower cover plate 15 and the upper cover plate 16, respectively.

[0039] Fixed sealing rings four, five, and six are made of the same material as fixed sealing ring 7, but have different specifications and models to simplify design and assembly.

[0040] The oil perforations on the lower cover plate 15 and the upper cover plate 16 are circular, circular groove, or arc groove.

[0041] It should be clear that the elastic force of the two springs 18 keeps the push ring 17 between the two movable sealing rings 6. Adjusting the distance between the two lower cover plates 15 and the upper cover plate 16 keeps the push ring 17 under a certain initial pressure on the two movable sealing rings 6, thereby keeping a certain initial sealing pressure between the two movable sealing rings 6 and the inner wall of the cylinder 1. The push ring 217, under the action of the fixed sealing ring 5 and the fixed sealing ring 6, divides the mounting cavity into an open upper oil cavity and a lower oil cavity; Since the push ring 2 17 moves up and down synchronously with the piston body 4, the push ring 2 17 only undergoes slight relative displacement with the piston rod 5 under the pressure difference of the upper and lower hydraulic oils of the piston body 4. Therefore, the friction between the inner wall of the push ring 2 17 and the fixed sealing ring 6 between the piston rod 5 is extremely small, and its wear is far less than that of the fixed sealing ring 5 (existing technology). Therefore, it will not introduce new sealing problems. Furthermore, the fixed sealing ring 6 is set as an elastic annular elastic steel sheet ring structure. The inner edge of the annular elastic steel sheet ring structure is welded or interference-sealed to the piston rod 5, and the outer edge of the annular elastic steel sheet ring structure is welded to the push ring 2 17. This can achieve a better isolation effect while ensuring the movement of the push ring 2 17. When hydraulic oil is input into the piston chamber of cylinder 1, it enters the upper or lower oil chamber through the oil passage of the lower cover plate 15 or the upper cover plate 16, respectively. This causes the pressure of the hydraulic oil to act on the upper or lower end face of the push ring 17, thereby pushing the push ring 17 to move. The push ring 17 is transmitted to the lower cover plate 15 and the upper cover plate 16 through two springs 18, thereby moving the piston rod 5. At the same time, under the action of hydraulic oil, the push ring 17 moves radially relative to the lower cover plate 15 and the upper cover plate 16 along the piston rod 5, thereby squeezing the pressure-bearing part of a movable sealing ring 6 through the extrusion part, causing the movable sealing ring 6 to expand radially outward. This causes the sealing pressure between the outer surface of the movable sealing ring 6 and the inner wall of cylinder 1 to increase adaptively. When the input hydraulic oil pressure decreases, the elastic force of the two springs 18 pushes the push ring 17 to move adaptively, thereby reducing the extrusion pressure on the movable sealing ring 6.

[0042] The extrusion part is a chamfer one of an annular structure concentrically arranged on the end face of the push ring 17, and the pressure bearing part is a chamfer two set on the inner wall edge of the movable sealing ring 6. The chamfer two matches and slides in contact with the chamfer one, and the angle of the chamfer one is preferably 75 degrees.

[0043] As an alternative, the floating drive of the second thrust ring 17 can also use hydraulic oil to act directly on the end face of the second thrust ring 17 to achieve more direct force transmission; in addition, the diameter of the oil passage hole can be selectively designed according to the viscosity and flow requirements of the hydraulic oil to ensure the sensitivity of pressure transmission.

[0044] like Figures 1 to 9As shown, this invention provides a high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles. During operation, the external hydraulic oil delivery system first introduces hydraulic oil into the piston chamber of cylinder 1 through connector 2 and discharges it through connector 3. Simultaneously, the piston body 4 and piston rod 5 move towards connector 3. Similarly, when hydraulic oil is introduced into the piston chamber of cylinder 1 through connector 3 and discharged through connector 2, the piston body 4 and piston rod 5 move towards connector 2. During this process, the fixed sealing ring 7 between the piston body 4 and the inner wall of cylinder 1 provides a fixed basic sealing performance, while the floating structure... Under pressure, the floating structure moves axially towards the piston body 4, causing the inner wall of the movable sealing ring 6 to be squeezed from the inside out, thus expanding the movable sealing ring 6 radially. After the movable sealing ring 6 expands, the sealing pressure between its outer surface and the inner wall of the cylinder body 1 increases. Furthermore, the greater the pressure of the hydraulic oil, the greater the internal squeezing force of the floating structure on the movable sealing ring 6, which in turn makes the expansion size of the movable sealing ring 6 larger. This means that the sealing pressure between the outer surface of the movable sealing ring 6 and the inner wall of the cylinder body 1 is greater, thus achieving self-adaptation between the sealing effect of the movable sealing ring 6 and the hydraulic oil pressure, and extending the maintenance cycle of the cylinder system.

[0045] The main beneficial effects achieved by this invention include: 1. The use of a floating structure and a movable sealing ring achieves a positive correlation and adaptive relationship between sealing force and hydraulic oil pressure, increasing sealing reliability and extending the maintenance cycle of the cylinder system; 2. To achieve stable operation and reduced wear under low-pressure conditions, while maintaining seal without failure under high-pressure conditions; 3. When the wear of the movable sealing ring is within the set range, its expansion can adaptively compensate for the wear, thereby ensuring that the sealing performance does not decrease; 4. Two high-density sponge rings scrape the inner wall of the cylinder to remove and absorb the attached debris, reducing the wear of debris on the movable sealing ring and the fixed sealing ring; 5. High-pressure lubricating oil is injected into the two sealed cavities through two oil fillers to lubricate the movable sealing rings and reduce the wear of the two movable sealing rings; 6. Adjust the initial sealing pressure between the outer wall of the two movable sealing rings and the inner wall of the cylinder to adapt to cylinders under different pressure conditions and improve versatility.

[0046] Although embodiments of the present invention have been shown and described, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments disclosed, but rather allows for changes, modifications, substitutions, and variations without departing from the principles of the present invention. For example, the elastic support layer may be replaced with silicone rubber or fluororubber to accommodate a wider temperature range; spring one may be replaced with a gas spring or a hydraulic damper to provide a more stable initial pressure; the floating drive of push ring two may be replaced with hydraulic oil acting directly on the end face of push ring two to achieve a more direct force transmission. The scope of protection of the present invention is defined by the appended claims and their equivalents.

[0047] The high-pressure, high-flow hydraulic cylinder system of the present invention, which extends the maintenance cycle, uses common mechanical methods for installation, connection, or setting. Any method that achieves the beneficial effect can be implemented. The cylinder body 1, connector 1, connector 2, piston body 3, piston rod 5, fixed sealing ring 7, spring 1, spring seat ring 10, screw 11, oil filler 12, retaining ring 13, high-density sponge ring 14, spring 2 18, elastic support layer 19, elastic friction layer 20, and short rod 21 of the high-pressure, high-flow hydraulic cylinder system of the present invention are commercially available. Technical personnel in this industry only need to install and operate it according to the accompanying instruction manual, without requiring any creative work from those skilled in the art.

[0048] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle, comprising a cylinder body (1), a piston chamber provided inside the cylinder body (1), a piston body (4) slidably installed in the piston chamber, a fixed sealing ring (7) provided on the outer wall of the piston body (4), the fixed sealing ring (7) sealing the piston body (4) and the inner wall of the cylinder body (1), a piston rod (5) installed on the upper end face of the piston body (4), the end of the piston rod (5) extending outward through the seal at the end of the cylinder body (1), and a connector one (2) and a connector two (3) communicating with the piston chamber installed on the side wall of the cylinder body (1), the connector one (2) and the connector two (3) being located on both sides of the piston body (4); characterized in that, It also includes a movable sealing ring (6) and a floating structure. The movable sealing ring (6) is annular and can expand and contract radially. The movable sealing ring (6) is concentrically mounted on the piston body (4). The outer surface of the movable sealing ring (6) slides in contact with the inner wall of the cylinder (1). The floating structure is concentrically mounted on the piston body (4). Under the pressure of the hydraulic oil, the floating structure moves along the axial direction of the piston body (4). The floating structure squeezes the inner wall of the movable sealing ring (6) outward, causing the movable sealing ring (6) to expand. After the movable sealing ring (6) expands, the pressure between it and the inner wall of the cylinder (1) changes synchronously with the pressure of the hydraulic oil.

2. The high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles as described in claim 1, characterized in that, The floating structure includes a short rod (21) and two push rings (8). Two movable sealing rings (6) are provided, and the two movable sealing rings (6) are respectively concentrically installed on the upper end face and the lower end face of the piston body (4). The short rod (21) is concentrically installed on the lower end face of the piston body (4). The two push rings (8) are respectively slidably fitted on the short rod (21) and the piston rod (5). The push rings (8) are annular, and the two push rings (8) are respectively located on the two movable sealing rings (6). On the upper and lower sides, springs (9) are installed on the ends of the two push rings (8) facing the piston body (4). The other ends of the two springs (9) are connected to the upper and lower end faces of the piston body (4) respectively. A squeezing part is provided on the end face of the push ring (8) facing the movable sealing ring (6). The inner walls of the two movable sealing rings (6) are provided with a pressure bearing part that matches the squeezing part of the push ring (8). The squeezing part squeezes the pressure bearing part, causing the movable sealing ring (6) to expand radially outward.

3. The high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles as described in claim 2, characterized in that, It also includes two spring seats (10), which are respectively mounted on the end faces of the two push rings (8) and the movable sealing ring (6) by multiple screws (11), and two springs (9) are respectively mounted on the two spring seats (10).

4. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle as described in claim 2, characterized in that, It also includes two oil filler nozzles (12), and each of the two push rings (8) has a through oil filling hole, and two oil filler nozzles (12) are installed on the oil filling holes of the two push rings (8).

5. A high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles as described in claim 2, characterized in that, It also includes two retaining rings (13), which are respectively installed on two push rings (8). High-density sponge rings (14) are provided on both retaining rings (13). The two high-density sponge rings (14) are used to clean the inner wall of the cylinder (1).

6. A high-pressure, high-flow hydraulic cylinder system for extending maintenance cycles as described in claim 1, characterized in that, The piston body (4) includes a lower cover plate (15) and an upper cover plate (16). The lower cover plate (15) and the upper cover plate (16) are installed at the lower end of the piston rod (5). An installation cavity is provided between the lower cover plate (15) and the upper cover plate (16). Oil passage holes are provided on both the lower cover plate (15) and the upper cover plate (16). Two movable sealing rings (6) are provided. The two movable sealing rings (6) are concentrically installed on the opposite end faces of the lower cover plate (15) and the upper cover plate (16). The oil passage holes are located inside the two movable sealing rings (6) and are arranged close to the piston rod (5). The floating structure includes a push ring. The second (17) push ring is located between the two movable sealing rings (6). The second push ring (17) is sleeved on the piston rod (5). The upper and lower ends of the second push ring (17) are provided with extrusion parts. The inner walls of the two movable sealing rings (6) are provided with pressure bearing parts that match the two extrusion parts of the second push ring (17). The extrusion parts extrude the pressure bearing parts, causing the movable sealing rings (6) to expand radially outward. The upper and lower ends of the second push ring (17) are both equipped with springs (18). The other ends of the two springs (18) are connected to the lower cover plate (15) and the upper cover plate (16) respectively.

7. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle as described in claim 6, characterized in that, The oil perforations on the lower cover plate (15) and the upper cover plate (16) are circular, circular groove, or arc groove.

8. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle as described in any one of claims 2 to 7, characterized in that, The extrusion part is a chamfer one of an annular structure concentrically arranged on the end face of the push ring (8), and the pressure bearing part is a chamfer two set on the inner wall edge of the movable sealing ring (6). The chamfer two matches and slides in contact with the chamfer one.

9. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle as described in any one of claims 1 to 8, characterized in that, The movable sealing ring (6) includes an elastic support layer (19) and an elastic friction layer (20). The inner surface of the elastic support layer (19) is chamfered, and the outer surface of the elastic support layer (19) is provided with an arc groove. The elastic friction layer (20) is fitted onto the outer arc groove of the elastic support layer (19).

10. A high-pressure, high-flow hydraulic cylinder system with extended maintenance cycle as described in claim 9, characterized in that, The elastic support layer (19) is made of nitrile rubber, hydrogenated nitrile rubber, or an elastic metal skeleton; the elastic friction layer (20) is made of polytetrafluoroethylene, polyurethane, or polyether ether ketone.

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