A sealing structure of an oil cylinder and a lifting oil cylinder

Abstract

This application relates to the field of hydraulic cylinders, specifically providing a cylinder sealing installation structure and a lifting cylinder, including a cylinder barrel, a cylinder head, a piston rod, a sealing ring assembly, and a pressure cap. The cylinder barrel is hollow to form a drive chamber for injecting pressurized fluid. The cylinder head is connected to one axial side of the cylinder barrel, and a sealing groove is provided on the side of the cylinder head away from the cylinder barrel. The piston rod is disposed in the drive chamber, and one end of the piston rod passes through the side wall of the cylinder barrel and the cylinder head in sequence. The sealing ring assembly is sleeved on the piston rod and located in the sealing groove, and the sealing ring is slidably connected to the piston rod. The pressure cap has a through hole for the piston rod to pass through, and the pressure cap is threadedly connected to the sealing groove and contacts the sealing ring assembly. This utility model allows for convenient adjustment of the sealing ring force, thereby avoiding the problem of decreased sealing performance due to wear of the cylinder head.

Description

Technical Field

[0001] This application relates to the field of hydraulic cylinder technology, and in particular to a cylinder sealing installation structure and a lifting cylinder. Background Technology

[0002] A hydraulic cylinder (also known as a hydraulic cylinder) is the core actuator in a hydraulic system. It is mainly used to convert hydraulic energy into mechanical energy and drive equipment to complete linear reciprocating motion.

[0003] The quality of the sealing ring on the cylinder head directly affects the cylinder's sealing performance. Existing cylinder heads mainly use a single-layer seal, where the sealing ring contacts the piston rod to achieve a seal. Long-term reciprocating motion can easily cause the sealing ring to wear out and loosen between it and the piston rod. This not only leads to a decrease in the cylinder's working performance but also causes material waste, environmental pollution, and affects production efficiency.

[0004] Therefore, there is an urgent need for a hydraulic cylinder sealing structure that can quickly adjust the sealing effect of the sealing ring according to the degree of wear of the sealing ring. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a hydraulic cylinder sealing installation structure and a lifting hydraulic cylinder, which aims to solve the problem that the existing hydraulic cylinder cannot conveniently adjust the sealing ring force, resulting in a decrease in the sealing performance of the hydraulic cylinder.

[0006] The technical solution adopted by this application to solve the technical problem is as follows: A hydraulic cylinder sealing installation structure, comprising:

[0007] A cylinder barrel, the interior of which is hollow to form a drive chamber for injecting hydraulic oil;

[0008] A cylinder head is connected to one axial side of the cylinder barrel. A sealing groove is provided on the side of the cylinder head away from the cylinder barrel, and the inner wall of the sealing groove is threaded.

[0009] A piston rod is disposed in the drive chamber, and one end of the piston rod passes through the side wall of the cylinder and the cylinder head in sequence;

[0010] A sealing ring assembly is sleeved on the piston rod and located in the sealing groove, and the sealing ring assembly is slidably connected to the piston rod;

[0011] A pressure cap is provided with a through hole for the piston rod to pass through. The pressure cap is threadedly connected to the sealing groove and is in contact with the sealing ring.

[0012] Optionally, the bottom of the sealing groove is provided with a raised sealing part, the cross-sectional profile of which matches the cross-sectional profile of the sealing ring assembly.

[0013] Optionally, the sealing ring assembly includes multiple V-shaped sealing rings, which are coaxially arranged and interlocked with each other.

[0014] Optionally, the outer diameter of the gland is equal to the diameter of the sealing groove.

[0015] Optionally, the pressure cap is annular, and multiple screw holes are provided on the outer periphery of the pressure cap. An adjusting screw is detachably installed in the through hole, and the adjusting screw is in contact with the sealing ring assembly.

[0016] Optionally, the pressure cap further includes an annular pressure plate, which is disposed in the sealing groove and contacts the adjusting screw.

[0017] Optionally, a scale extending axially along the piston rod is provided on the outer wall of the gland for observing the position of the gland.

[0018] Optionally, the cylinder head is bolted to the cylinder barrel.

[0019] Optionally, the cylinder head may form at least one plane in its circumferential direction.

[0020] This embodiment also proposes a lifting cylinder, including the cylinder sealing mounting structure as described in any of the preceding embodiments.

[0021] Compared with the prior art, the embodiments of this application, after machining a sealing groove on the cylinder head, thread the inner wall of the sealing groove and install a pressure cap. By adjusting the depth of the pressure cap entering the sealing groove through the thread, the sealing ring assembly in the sealing groove is pressurized. This allows for convenient adjustment of the combined sealing ring force, making the sealing ring tighter and gripping the piston rod, thus avoiding the problem of decreased sealing performance of the cylinder due to wear of the sealing ring over a long period of time. Attached Figure Description

[0022] Figure 1 This is a three-dimensional schematic diagram of a hydraulic cylinder sealing installation structure proposed in an embodiment of this application;

[0023] Figure 2 This is an exploded schematic diagram of a hydraulic cylinder sealing installation structure proposed in an embodiment of this application;

[0024] Figure 3 This is a side view of a cylinder sealing installation structure proposed in an embodiment of this application;

[0025] Figure 4 yes Figure 2 A magnified view of a portion of point C in the middle;

[0026] Figure 5 yes Figure 3 A partial sectional view cut along section AA.

[0027] Figure 6 This is a cross-sectional view of the sealing ring assembly in an embodiment of this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 10. Cylinder barrel; 11. Drive chamber; 20. Cylinder head; 21. Sealing groove; 30. Piston rod; 40. Sealing ring assembly; 41. V-shaped sealing ring; 50. Pressure cap; 51. Adjusting screw. Detailed Implementation

[0030] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0031] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0033] Whether it's a differential hydraulic cylinder or a single-rod or double-rod hydraulic cylinder, they all use a hydraulic pump to drive high-pressure oil to move the piston rod and achieve mechanical lifting. Therefore, one end of the piston cylinder is located inside the cylinder barrel, and the other end protrudes from the cylinder head. A sealing ring is installed between the cylinder head and the cylinder barrel, which is fitted onto the piston rod to prevent high-pressure oil from leaking from the opening at the cylinder head. Because the piston rod will constantly rub against the sealing ring during movement, gaps will form between the sealing ring and the piston, causing it to loosen and reducing the sealing effect. Therefore, after the hydraulic cylinder has been used for a period of time, the sealing ring needs to be replaced. Existing hydraulic cylinder sealing rings are usually located on the inside and outside of the cylinder barrel opening, making replacement inconvenient.

[0034] Based on this, see Figure 1 and Figure 2 In this embodiment, by pressurizing the sealing ring, the sealing ring is compressed and expanded, further tightening the piston rod 30. To achieve linear pressurization and convenient sealing ring replacement, this application proposes a hydraulic cylinder sealing installation structure, including a cylinder barrel 10, a cylinder head 20, a piston rod 30, a sealing ring assembly 40, and a pressure cap 50. The cylinder barrel 10 is hollow to form a drive chamber 11 for injecting hydraulic oil; the cylinder head 20 is connected to one axial side of the cylinder barrel 10, and a sealing groove 21 is provided on the side of the cylinder head 20 away from the cylinder barrel 10. The inner wall of the sealing groove 21 is provided with threads; the piston rod 30 is disposed in the driving cavity 11, and one end of the piston rod 30 passes through the side wall of the cylinder 10 and the cylinder head 20 in sequence; the sealing ring assembly 40 is sleeved on the piston rod 30 and located in the sealing groove 21, and the sealing ring assembly 40 is slidably connected to the piston rod 30; the pressure cap 50 is provided with a through hole for the piston rod 30 to pass through, and the pressure cap 50 is disposed in the sealing groove 21 by threaded connection and is in contact with the sealing ring assembly 40. One end of the cylinder barrel 10 has an opening through which the piston rod 30 passes. The cylinder head 20 has an inwardly extending sealing groove 21. The bottom of the sealing groove 21 also has an opening through which the piston rod 30 passes. That is, a channel for the piston rod 30 to pass through is formed in the middle of the cylinder head 20. A step is formed in the middle of the channel, so that the opening diameters on both sides of the channel are different. The sealing ring assembly 40 is fitted on the piston rod 30 and placed in the sealing groove 21 to isolate the inside of the cylinder barrel 10 from the outside. An annular pressure cap 50 is provided and machined on the outside of the pressure cap 50. The gland 50 is installed in the sealing groove 21 via screws. The gland 50 presses down on the sealing ring assembly 40, causing the sealing ring assembly 40 to open and tightly grip the piston rod 30, effectively improving the sealing performance. Because the gland 50 is installed in the sealing groove 21 via threads, the pressure change adjustment of the gland 50 on the sealing ring assembly 40 is linear, allowing for more accurate application of pressure to the sealing ring assembly 40 and preventing excessive or insufficient force on the sealing ring assembly 40. The gland 50 also has a through hole in the middle for the piston rod 30 to pass through. See also... Figure 5By setting the threaded connection between the gland 50 and the sealing ring assembly 40, on the one hand, by tightening the gland 50, the pressure on the sealing ring assembly 40 can be gradually increased after the sealing ring assembly 40 wears, so that the sealing ring assembly 40 is in the best sealing state. On the other hand, the sealing groove 21 can be easily opened to replace the sealing ring assembly 40, reducing maintenance costs.

[0035] In some embodiments, the bottom of the sealing groove 21 is provided with a raised sealing portion, the cross-sectional profile of which matches the cross-sectional profile of the sealing ring assembly 40. The sealing portion is annularly disposed at the bottom of the sealing groove 21, and its diameter matches that of the sealing ring assembly 40. In this embodiment, the cross-sectional profile of the sealing portion is triangular, so that the sealing portion fits snugly against the bottom of the sealing ring assembly 40, thereby improving the sealing effect.

[0036] See Figure 3 and Figure 6 In some embodiments, the sealing ring assembly 40 includes a plurality of V-shaped sealing rings 41, which are coaxially arranged and interlocked with each other. Since the upper and lower sides of the V-shaped sealing rings 41 are respectively provided with protrusions and matching grooves, when multiple V-shaped sealing rings 41 are stacked, they can fully fill the gaps between the sealing rings, thus improving the sealing performance.

[0037] See Figure 4 In some embodiments, the outer diameter of the gland 50 is equal to the diameter of the sealing groove 21. The gland 50 can be screwed into the sealing cap, and the structure of the gland 50 is simple and easy to manufacture.

[0038] See Figure 4 In some embodiments, the pressure cap 50 is annular, and multiple screw holes are provided on the outer periphery of the pressure cap 50. Adjusting screws 51 are detachably installed in the through holes, and the adjusting screws 51 are in contact with the sealing ring assembly 40. By providing several adjusting screws 51, the sealing ring assembly 40 can be further pressed down, making it easy to adjust the pressing force, thereby allowing the sealing ring assembly 40 to grip the piston rod 30.

[0039] In an optional embodiment, the pressure cap 50 further includes an annular pressure plate disposed in the sealing groove 21 and in contact with the adjusting screw 51.

[0040] In some embodiments, a scale extending axially along the piston rod 30 is provided on the outer wall of the pressure cap 50 for observing the position of the pressure cap 50. By comparing the depth of entry indicated by the scale, the depth to which the pressure cap 50 enters the sealing groove 21 can be seen more intuitively, thereby determining the tightness of the sealing ring and facilitating adjustment by the worker.

[0041] In some embodiments, the cylinder head 20 is bolted to the cylinder barrel 10. The bolted connection facilitates the disassembly and installation of the cylinder head 20.

[0042] In some embodiments, the cylinder head 20 has at least one circumferential plane. By providing a plane, the cylinder head 20 can be more easily installed onto the cylinder barrel 10.

[0043] This application also proposes a lifting cylinder, including the cylinder sealing mounting structure as described in any of the preceding claims. Therefore, the lifting cylinder has all the aforementioned beneficial effects, which will not be repeated here.

[0044] In this embodiment, after machining a sealing groove on the cylinder head, threads are cut into the inner wall of the sealing groove and a pressure cap is installed. The depth of the pressure cap entering the sealing groove is adjusted by the threads to pressurize the sealing ring assembly in the sealing groove. This allows for convenient adjustment of the combined sealing ring force, making the sealing ring tighter and gripping the piston rod, thus preventing the cylinder from experiencing a decrease in sealing performance due to sealing ring wear over a long period of time.

[0045] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A hydraulic cylinder sealing installation structure, characterized in that, include: A cylinder barrel, the interior of which is hollow to form a drive chamber for injecting hydraulic oil; A cylinder head is connected to one axial side of the cylinder barrel. A sealing groove is provided on the side of the cylinder head away from the cylinder barrel, and the inner wall of the sealing groove is threaded. A piston rod is disposed in the drive chamber, and one end of the piston rod passes through the side wall of the cylinder and the cylinder head in sequence; A sealing ring assembly is sleeved on the piston rod and located in the sealing groove, and the sealing ring assembly is slidably connected to the piston rod; A pressure cap is provided with a through hole for the piston rod to pass through. The pressure cap is threadedly connected to the sealing groove and is in contact with the sealing ring.

2. The cylinder sealing installation structure according to claim 1, characterized in that, The bottom of the sealing groove is provided with a raised sealing part, and the cross-sectional profile of the sealing part matches the cross-sectional profile of the sealing ring assembly.

3. The cylinder sealing installation structure according to claim 1, characterized in that, The sealing ring assembly includes multiple V-shaped sealing rings, which are coaxially arranged and interlocked with each other.

4. The cylinder sealing installation structure according to claim 1, characterized in that, The outer diameter of the gland is equal to the diameter of the sealing groove.

5. The cylinder sealing installation structure according to claim 1, characterized in that, The pressure cap is annular, and multiple screw holes are provided on the outer periphery of the pressure cap. An adjusting screw is detachably installed in the through hole, and the adjusting screw is in contact with the sealing ring assembly.

6. The cylinder sealing installation structure according to claim 5, characterized in that, The pressure cap also includes an annular pressure plate, which is disposed in the sealing groove and contacts the adjusting screw.

7. The cylinder sealing installation structure according to claim 1, characterized in that, A scale extending axially along the piston rod is provided on the outer wall of the pressure cap for observing the position of the pressure cap.

8. The cylinder sealing installation structure according to claim 1, characterized in that, The cylinder head is bolted to the cylinder barrel.

9. The cylinder sealing installation structure according to claim 1, characterized in that, The cylinder head forms at least one plane in its circumferential direction.

10. A lifting cylinder, characterized in that, Includes the cylinder sealing mounting structure as described in any one of claims 1 to 9.

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