Hydraulic cylinder structure and method for quick, non-disassembly seal replacement at sea

Abstract

This invention discloses a hydraulic cylinder structure and method for quick, non-disassembly replacement of seals at sea. The structure includes a cylinder barrel, a piston rod disposed inside the cylinder barrel, and an initial sealing piston mounted at the end of the piston rod. The end face of the initial sealing piston has a shoulder and a stepped shaft arranged sequentially away from the piston rod. The stepped shaft has at least two locking elements along its circumference. A sealing spare is disposed at the end of the cylinder barrel away from the initial sealing piston. The sealing spare has a through hole along its axial direction that transitions with the stepped shaft. The inner wall of the through hole has an annular groove that mates with the locking elements. The end of the sealing spare near the initial sealing piston has a first stepped hole that transitions with the shoulder. The beneficial effect of this invention is that the initial sealing piston can be quickly and directly pushed into the sealing spare on-site without disassembly, directly connecting the initial sealing piston and the sealing spare, allowing the initial sealing piston to quickly restore its sealing performance and continue operation.

Description

Technical Field

[0001] This invention relates to the field of hydraulic cylinder technology, and in particular to a hydraulic cylinder structure and method for quick replacement of seals without disassembly at sea. Background Technology

[0002] Hydraulic cylinders are key actuators in hydraulic systems. Their working principle involves using the piston movement between the cylinder barrel and piston rod to deliver high-pressure hydraulic oil to the next stage of the hydraulic system; or vice versa, using hydraulic oil to drive the piston rod and cylinder barrel in relative motion, thereby driving or maintaining the function of other mechanical structures. The ability of hydraulic oil to drive piston movement, or for piston movement to deliver hydraulic oil, relies on the sealing elements between the cylinder barrel and piston rod; therefore, the service life of these sealing elements determines the service life and performance of the hydraulic cylinder. Two main factors affect the sealing elements of a hydraulic cylinder: the cleanliness of the hydraulic cylinder itself and the smoothness of the surfaces of the piston's mating structures.

[0003] The service life of a hydraulic cylinder fundamentally depends on the service life of its sealing rings. When the sealing rings reach the end of their service life, they must be replaced. While the material cost of sealing rings is relatively inexpensive, the difficulty and cost of replacing them gradually increase for large hydraulic cylinders, those operating in special environments, and especially those used in seawater. Furthermore, the natural environment can significantly impact the cost and time required for replacement, leading to project delays and wasted resources. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a hydraulic cylinder structure and method for quick replacement of sealing rings without disassembly at sea, mainly solving the problem that hydraulic cylinders require disassembly to replace the sealing piston.

[0005] To address the aforementioned technical problems, the first aspect of this invention proposes a hydraulic cylinder structure for quick, non-disassembly replacement of seals at sea, comprising a cylinder barrel, a piston rod disposed inside the cylinder barrel, and an initial sealing piston mounted on the end of the piston rod. The end face of the initial sealing piston is sequentially provided with a shoulder and a stepped shaft in the direction away from the piston rod. The stepped shaft is provided with at least two locking elements along its circumference. A sealing spare is provided at the end of the cylinder barrel away from the initial sealing piston. The sealing spare has a through hole along its axial direction that transitions with the stepped shaft. The inner wall of the through hole is provided with an annular groove that mates with the locking elements. The end of the sealing spare near the initial sealing piston has a first stepped hole that transitions with the shoulder.

[0006] In some embodiments, each of the locking elements includes a keyway, a spring disposed at the bottom of the keyway, and a locking key disposed at the upper end of the spring, with an annular retaining sleeve covering the upper end face of each locking key, causing the locking key to press the locking key completely into the keyway.

[0007] In some embodiments, a second stepped hole is further provided at the connection position between the through hole and the first stepped hole to transitionally engage with the annular retaining sleeve.

[0008] In some embodiments, the depth of the annular groove is less than the height of the key.

[0009] In some embodiments, the annular retaining sleeve is a silicone sealing ring.

[0010] In some embodiments, the spring is a compression spring.

[0011] In some embodiments, a sealing ring is provided on the end face of the shoulder, and the sealing ring protrudes toward the sealing component.

[0012] In some embodiments, a limiting sleeve is also included, which is disposed on the rear end cover surface of the cylinder.

[0013] In some embodiments, the limiting sleeve is detachably connected to the rear end cover of the cylinder.

[0014] The second aspect of this invention proposes a method for quick, non-disassembly replacement of seals in marine hydraulic cylinders. A spare seal is pre-installed in the rodless cavity of the cylinder barrel. When the performance of the initial sealing piston at the piston rod end deteriorates, the initial sealing piston is pushed into the spare seal through the piston rod. The self-locking action of the initial sealing piston and the spare seal is used to form a new sealing piston.

[0015] The beneficial effects of this invention are as follows: a sealing spare part is reserved in the rodless cavity of the cylinder, and an annular groove is provided inside the sealing spare part. A matching locking part is provided on the end face of the initial sealing piston. When the initial sealing piston is worn or leaks oil, the initial sealing piston can be quickly and directly pushed into the sealing spare part on site without disassembly. Through the locking effect provided by the locking part and the annular groove, and the sealing effect provided by the shaft shoulder and the first step hole, the initial sealing piston and the sealing spare part are directly connected, so that the initial sealing piston can quickly restore its sealing performance and continue to work. This not only greatly reduces maintenance costs, but also extends the working cycle of the hydraulic cylinder. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the hydraulic cylinder structure for quick replacement of seals at sea without disassembly, as disclosed in Embodiment 1 of the present invention.

[0017] Figure 2 This is a schematic diagram of the structure of the initial sealing piston disclosed in Embodiment 1 of the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of the sealing spare part disclosed in Embodiment 1 of the present invention;

[0019] Figure 4 This is a schematic diagram of the installation of the initial sealing piston and sealing spare parts disclosed in Embodiment 1 of the present invention;

[0020] Figure 5 This is a schematic diagram of the locking component disclosed in Embodiment 1 of the present invention;

[0021] Figure 6 This is a schematic diagram of another hydraulic cylinder structure for quick, non-disassembly-resistant replacement of seals at sea, as disclosed in Embodiment 2 of the present invention.

[0022] Wherein: 1-cylinder, 2-piston rod, 3-initial sealing piston, 4-sealing spare part, 5-limiting sleeve, 301-shoulder, 302-stepped shaft, 303-locking part, 304-sealing ring, 401-through hole, 402-annular groove, 403-first step hole, 404-second step hole, 3031-keyway, 3032-spring, 3033-locking key, 3034-annular retaining sleeve. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the content of this invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to this invention are shown in the accompanying drawings, not all of them.

[0024] Example 1

[0025] This embodiment proposes a hydraulic cylinder structure for quick, non-disassembly seal replacement at sea, such as... Figure 1 As shown, it includes a cylinder 1, a piston rod 2 disposed inside the cylinder 1, and an initial sealing piston 3 installed at the end of the piston rod 2, as follows. Figure 2 As shown, the end face of the initial sealing piston 3 is provided with a shoulder 301 and a stepped shaft 302 in sequence in the direction away from the piston rod 2. The stepped shaft 302 is provided with at least two locking elements 303 along its circumference. A sealing element 4 is provided at the end of the cylinder 1 away from the initial sealing piston 3, such as... Figure 3As shown, the sealing spare part 4 has a through hole 401 along its own axial direction that transitions with the stepped shaft 302. This through hole 401 ensures the flow of hydraulic oil in the rodless chamber of the cylinder 1 when the sealing spare part 4 is not in use. The inner wall of the through hole 401 has an annular groove 402 that mates with the locking member 303. The end of the sealing spare part 4 near the initial sealing piston 3 has a first stepped hole 403 that transitions with the shaft shoulder 301. The locking relationship between the initial sealing piston 3 and the sealing spare part 4 is described in [reference missing]. Figure 4 .

[0026] In this embodiment, a sealing spare part 4 is reserved in the rodless cavity of the cylinder 1, and an annular groove 402 is provided inside the sealing spare part 4. A matching locking part 303 is provided on the end face of the initial sealing piston 3. When the initial sealing piston 3 is worn or leaks oil, the initial sealing piston 3 can be quickly and directly pushed into the sealing spare part 4 on site without disassembly. Through the locking effect provided by the locking part 303 and the annular groove 402, and the sealing effect provided by the shoulder 301 and the first stepped hole 403, the initial sealing piston 3 and the sealing spare part 4 are directly connected, so that the initial sealing piston 3 can quickly restore its sealing performance and continue to work. This not only greatly reduces maintenance costs, but also extends the working cycle of the hydraulic cylinder.

[0027] By referring to the above method, multiple sealing spare parts 4 can be reserved, which can effectively extend the design working cycle by two times or more. However, too many sealing spare parts 4 will shorten the stroke of the piston rod 2. Furthermore, when there are more than two sealing spare parts 4, corresponding locking units should be set for two adjacent sealing spare parts 4. Specifically, refer to the locking element 303 and the annular groove 402 mentioned above.

[0028] The aforementioned locking element 303 can be any mechanical unit capable of providing radial extension and retraction. In one example, such as... Figure 5 As shown, the stepped shaft 302 has three locking elements 303 arranged circumferentially. Each locking element 303 includes a keyway 3031, a spring 3032 placed at the bottom of the keyway 3031, and a locking key 3033 placed at the upper end of the spring 3032. An annular retaining sleeve 3034 covers the upper surface of each locking key 3033, allowing the locking key 3033 to be fully pressed into the keyway 3031. In the above scheme, the annular retaining sleeve 3034 is fitted around the periphery of the stepped shaft 302 and needs to cover all the keyways 3031 to ensure that the locking key 3033 is fully pressed into the keyway 3031. The annular retaining sleeve 3034 can be a silicone sealing ring or a metal ring. If a metal ring is used, the metal ring is interference-fitted to the periphery of the stepped shaft 302.

[0029] To accommodate the locking element 303 mentioned in the above example, a second step hole 404 is also provided at the connection position between the through hole 401 and the first step hole 403 to transitionally engage with the annular retaining sleeve 3034. In this embodiment, the space reserved in the second step hole 404 is used to avoid the annular retaining sleeve 3034 during the process of the initial sealing piston 3 being pushed into the sealing spare part 4.

[0030] By implementing the above implementation scheme, during the advancement of the initial sealing piston 3, the annular retaining sleeve 3034 is first limited by the end face of the second stepped hole 404 and cannot enter the through hole 401. It can only remain in the second stepped hole 404 as the first seal. After the retaining key 3033 loses the limitation of the annular retaining sleeve 3034, the inner wall of the through hole 401 continues to provide radial limitation. Finally, the shoulder 301 abuts against the first stepped hole 403, and the initial sealing piston 3 is axially limited. At the same time, the retaining key 3033 is pushed into the annular groove 402 by the elastic force of the spring 3032, and the initial sealing piston 3 and the sealing spare part 4 are locked.

[0031] Specifically, the depth of the annular groove 402 is less than the height of the key 3033. Therefore, after the key 3033 is subjected to the elastic force of the spring 3032, only a portion of it is pushed into the annular groove 402. Thus, the upper and lower ends of the key 3033 are located within the annular groove 402 and the keyway 3031, respectively, achieving the initial locking of the sealing piston 3 and the sealing spare part 4. More preferably, the end face of the key 3033 is machined into an arc surface.

[0032] Specifically, the spring 3032 mentioned above is a compression spring, which continuously provides radial outward thrust to the retaining key 3033. Other elastic components can also be used.

[0033] More preferably, a sealing ring 304 is provided on the end face of the shoulder 301. The sealing ring 304 protrudes towards the sealing component 4. During the process of the initial sealing piston 3 being pushed towards the sealing component 4, the sealing ring 304 is squeezed by the shoulder 301 and the first stepped hole 403 to form a second seal.

[0034] Example 2

[0035] Based on Embodiment 1, in order to ensure the normal working stroke of the hydraulic cylinder and to avoid premature use of spare parts, a preferred embodiment further includes a limiting sleeve 5, such as... Figure 6 As shown, the limiting sleeve 5 is installed on the surface of the rear end cover of the cylinder 1. The limiting sleeve 5 is detachably connected to the rear end cover of the cylinder 1. Removing the limiting sleeve 5 allows the piston rod 2 to be pressed and the sealing spare part 4 to be activated to continue operation.

[0036] Example 3

[0037] This embodiment proposes a method for quick replacement of seals in marine hydraulic cylinders without disassembly. A spare seal 4 is reserved in the rodless cavity of the cylinder 1. When the performance of the initial sealing piston 3 at the end of the piston rod 2 deteriorates, the initial sealing piston 3 is pushed into the spare seal 4 through the piston rod 2. The self-locking effect of the initial sealing piston 3 and the spare seal 4 is used to form a new sealing piston.

[0038] One method for quick replacement without disassembly can refer to the structure described in Embodiment 1, but the implementation is not limited to the structure described in Embodiment 1. Any structure that sets up multi-stage sealing spare parts 4 in the cylinder 1 and makes the initial sealing piston 3 and sealing spare parts 4 self-lock by controlling the one-way stroke of the piston rod 2 can be considered as an equivalent and replaceable solution.

[0039] The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made based on the essence of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A hydraulic cylinder structure for quick, non-disassembly seal replacement at sea, comprising a cylinder barrel, a piston rod disposed inside the cylinder barrel, and an initial sealing piston mounted at the end of the piston rod, characterized in that, The end face of the initial sealing piston is provided with a shoulder and a stepped shaft in sequence in the direction away from the piston rod. The stepped shaft is provided with at least two locking members along its circumference. A sealing spare is provided at the end of the cylinder away from the initial sealing piston. The sealing spare is provided with a through hole along its axial direction that transitions with the stepped shaft. The inner wall of the through hole is provided with an annular groove that mates with the locking members. The end of the sealing spare near the initial sealing piston is provided with a first stepped hole that transitions with the shoulder.

2. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 1, characterized in that, Each of the locking elements includes a keyway, a spring placed at the bottom of the keyway, and a locking key placed at the upper end of the spring. An annular retaining sleeve covers the upper surface of each locking key, causing the locking key to be fully pressed into the keyway.

3. The hydraulic cylinder structure for quick, non-disassembly-based replacement of seals at sea as described in claim 2, characterized in that, The connection position between the through hole and the first stepped hole is also provided with a second stepped hole that transitions with the annular retaining sleeve.

4. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 2, characterized in that, The depth of the annular groove is less than the height of the key.

5. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 2, characterized in that, The annular retaining sleeve is a silicone sealing ring.

6. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 2, characterized in that, The spring is a compression spring.

7. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 1, characterized in that, A sealing ring is provided on the end face of the shoulder, and the sealing ring protrudes in the direction close to the sealing component.

8. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 1, characterized in that, It also includes a limiting sleeve, which is disposed on the surface of the rear end cover of the cylinder.

9. The hydraulic cylinder structure for quick-change of seals without disassembly at sea as described in claim 8, characterized in that, The limiting sleeve is detachably connected to the rear end cover of the cylinder.

10. A method for quick, non-disassembly replacement of seals on a marine hydraulic cylinder, characterized in that... A sealing spare is reserved in the rodless chamber of the cylinder. When the performance of the initial sealing piston at the end of the piston rod deteriorates, the initial sealing piston is pushed into the sealing spare through the piston rod. The self-locking effect of the initial sealing piston and the sealing spare is used to form a new sealing piston.

Images