Sealing device for high-pressure-resistant piston rod of pure water hydraulic cylinder

Abstract

The high-pressure-resistant piston rod sealing device for the pure water hydraulic cylinder comprises an elastic layer, a bonding layer and a wear-resistant layer, and the elastic layer is arranged on the outer side of the wear-resistant layer and connected with the wear-resistant layer through the bonding layer. According to the high-pressure-resistant piston rod sealing device for the pure water hydraulic cylinder, the elastic layer, the wear-resistant layer and the bonding layer are combined, the good wear resistance and sealing performance are achieved under the condition that the size of the groove is not changed, and the service life of the piston rod sealing ring is prolonged.

Description

Technical Field

[0001] This utility model belongs to the field of sealing ring technology, specifically relating to a high-pressure piston rod sealing device for pure water hydraulic cylinders. Background Technology

[0002] The seal between the hydraulic cylinder and the piston rod needs to be achieved through a piston rod sealing ring. However, pure water hydraulic cylinders use pure water as the medium. Pure water has problems such as poor lubrication, high friction, low viscosity, and easy leakage compared to hydraulic fluid. Existing piston rod sealing rings are difficult to use in pure water hydraulic cylinders.

[0003] In the prior art, such as the piston rod buffer seal ring of a novel hydraulic cylinder disclosed in Chinese Patent CN 204610427 U, there is an annular groove. This groove forms an inner lip that contacts the piston rod and an outer lip that contacts the cylinder body of the flexible seal ring. The seal ring also has a retaining ring, which enhances the sealing effect between the inner lip and the piston rod. The flexible seal ring body of this utility model also has a preferred reinforcing structure. This reduces the frictional resistance of the seal ring to the piston rod without weakening the sealing effect. However, in the prior art, the poor lubricity of pure water as a medium greatly increases the frictional force between the seal ring and the piston rod, reducing the service life of the seal ring. Utility Model Content

[0004] The purpose of this invention is to provide a high-pressure piston rod sealing device for pure water hydraulic cylinders, which solves the problem in the prior art where the friction of the sealing ring and the piston rod greatly increases, reducing the service life of the sealing ring.

[0005] Therefore, this utility model provides a high-pressure piston rod sealing device for a pure water hydraulic cylinder, comprising: an elastic layer, a bonding layer and a wear-resistant layer, wherein the elastic layer is outside the wear-resistant layer and the elastic layer is connected to the wear-resistant layer through the bonding layer.

[0006] Preferably, the inner surface of the elastic layer is provided with a protrusion. The elastic layer provides sufficient sealing preload to the wear-resistant layer through the protrusion and also compensates for the wear-resistant layer, thereby improving the sealing performance of the piston rod seal ring.

[0007] Preferably, the thickness of the middle part of the protrusion is greater than the thickness of the two ends, and the thickness of the two ends of the protrusion is the same.

[0008] Preferably, the outer surface of the bonding layer is provided with a concave portion, which fits against the protrusion.

[0009] Preferably, the concave portion is provided with a mesh-like reinforcing strip. The fit between the concave portion of the bonding layer and the protrusion of the elastic layer, together with the mesh-like reinforcing strip on the concave portion, can strengthen the bonding force between the elastic layer and the bonding layer, preventing movement between the wear-resistant layer and the elastic layer.

[0010] Preferably, the inner surface of the wear-resistant layer is provided with a cylindrical surface, a first conical surface, and a second conical surface. The first conical surface and the second conical surface are connected and in opposite directions, forming a protruding lip structure. The cylindrical surface is connected to the second conical surface. The lip structure, while ensuring sealing, reduces the contact area between the wear-resistant layer and the piston rod, thereby reducing wear on the wear-resistant layer and lowering the pressure in the sealing area.

[0011] Preferably, the first conical surface extends from one end of the wear-resistant layer to the other end of the wear-resistant layer to one end of the second conical surface, with the thickness gradually increasing; the second conical surface extends from one end close to the first conical surface to the other end of the wear-resistant layer to the cylindrical surface, with the thickness gradually decreasing.

[0012] Preferably, the ratio of the height of the lip structure to the total height of the wear-resistant layer is in the range of 1:2 to 1:4.

[0013] Preferably, the height ratio between the first conical surface and the second conical surface is in the range of 1:2 to 1:4.

[0014] Preferably, the ratio of the maximum thickness of the lip structure to the thickness of the cylindrical surface is in the range of 1:0.5-1:2.

[0015] Preferably, the elastic layer is made of rubber, and the wear-resistant layer is made of polyurethane.

[0016] More preferably, the wear-resistant layer is made of ultra-high molecular weight polyethylene.

[0017] Beneficial effects:

[0018] 1. This utility model provides a high-pressure piston rod sealing device for pure water hydraulic cylinders. Through the combination of an elastic layer, a wear-resistant layer and a bonding layer, it has good wear resistance and sealing performance without changing the groove size, thereby improving the service life of the piston rod sealing ring.

[0019] 2. In existing technologies, the piston rod seal ring does not have a wear-resistant layer. In pure water hydraulic cylinders, the lubrication of the pure water medium is poor, resulting in high friction between the piston rod seal ring and the piston rod, leading to rapid wear. This invention incorporates a wear-resistant layer inside the elastic layer, improving the wear resistance between the seal ring and the piston rod, and extending the seal ring's service life. However, the bond between the elastic layer and the wear-resistant layer is prone to shifting. This invention addresses this by using a bonding layer to connect the elastic layer and the wear-resistant layer, and incorporating a mesh-like reinforcing rib on the bonding layer to enhance the bonding strength between the elastic layer and the bonding layer, preventing shifting between them.

[0020] 3. The elastic layer provides sufficient sealing preload to the wear-resistant layer through the protrusions, and also compensates for the wear-resistant layer, thereby improving the sealing performance of the piston rod seal ring.

[0021] 4. The lip structure reduces the contact area between the wear-resistant layer and the piston rod while ensuring a tight seal, thereby reducing wear on the wear-resistant layer and lowering the pressure in the sealing area. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of an embodiment of a high-pressure piston rod sealing device for a pure water hydraulic cylinder provided by this utility model.

[0024] Figure 2 A cross-sectional view of the wear-resistant layer of an embodiment of a high-pressure piston rod sealing device for a pure water hydraulic cylinder provided by this utility model.

[0025] Figure 3 This is a schematic diagram of the bonding layer of an embodiment of a high-pressure piston rod sealing device for a pure water hydraulic cylinder provided by this utility model.

[0026] In the diagram: 1-elastic layer, 11-protrusion, 2-bonding layer, 21-recessed portion, 22-reinforcing strip, 3-wear-resistant layer, 31-cylindrical surface, 32-first conical surface, 33-second conical surface, H1-total height of wear-resistant layer, H2-height of lip structure, H3-height of first conical surface, H4-height of second conical surface, B1-maximum thickness of lip structure, B2-thickness of cylindrical surface. Detailed Implementation

[0027] The following detailed description of preferred embodiments of the present invention, along with the included examples, will make the content of the present invention more readily understood. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of any conflict, the definitions in this specification shall prevail.

[0028] Example 1:

[0029] Provided such as Figure 1-3 The present invention provides a high-pressure piston rod sealing device for a pure water hydraulic cylinder. Through the combination of an elastic layer, a wear-resistant layer and a bonding layer, it has good wear resistance and sealing performance without changing the groove size, thereby improving the service life of the piston rod sealing ring.

[0030] like Figure 1-2 As shown, a high-pressure piston rod sealing device for a pure water hydraulic cylinder includes: an elastic layer 1, a bonding layer 2, and a wear-resistant layer 3. The elastic layer 1 is located outside the wear-resistant layer 3 and is connected to the wear-resistant layer 3 through the bonding layer 2.

[0031] The inner surface of the elastic layer 1 is provided with a protrusion 11. The thickness of the protrusion 11 in the middle is greater than that at both ends, and the thickness at both ends of the protrusion 11 is the same. The elastic layer 1 provides sufficient sealing preload to the wear-resistant layer 3 through the protrusion 11, and also plays a compensating role for the wear-resistant layer 3, thereby improving the sealing performance of the piston rod sealing ring.

[0032] The outer surface of the bonding layer 2 has a recessed portion 21 that fits against the protrusion 11. A mesh-like reinforcing strip 22 is provided on the recessed portion 21. The fit between the recessed portion 21 of the bonding layer 2 and the protrusion 11 of the elastic layer 1, along with the mesh-like reinforcing strip 22 on the recessed portion 21, strengthens the bond between the elastic layer 1 and the bonding layer 2, preventing movement between the wear-resistant layer 3 and the elastic layer 1.

[0033] The inner surface of the wear-resistant layer 3 is provided with a cylindrical surface 31, a first conical surface 32, and a second conical surface 33. The first conical surface 32 and the second conical surface 33 are connected and in opposite directions, forming a protruding lip structure. The cylindrical surface 31 is connected to the second conical surface 33. The first conical surface 32 extends from one end of the wear-resistant layer 3 to the other end of the wear-resistant layer 3, and its thickness gradually increases. The second conical surface 33 extends from the end near the first conical surface 32 to the other end of the wear-resistant layer 3, and its thickness gradually decreases. The ratio of the height H2 of the lip structure to the total height H1 of the wear-resistant layer 3 is 1:3. The ratio of the height H3 of the first conical surface 32 to the height H4 of the second conical surface 33 is 1:3. The ratio of the maximum thickness B1 of the lip structure to the thickness B2 of the cylindrical surface 31 is 1:1. Under the condition of ensuring sealing, the lip structure reduces the contact area between the wear-resistant layer 3 and the piston rod, thereby reducing the wear of the wear-resistant layer 3 and reducing the pressure in the sealing area.

[0034] The elastic layer 1 is made of rubber, and the wear-resistant layer 3 is made of ultra-high molecular weight polyethylene.

[0035] As shown in the figure, the piston rod seal ring in this embodiment is used in a pure water hydraulic cylinder. The pure water hydraulic cylinder has a sealing groove, and the piston rod seal ring is placed within the sealing groove, through which the piston rod passes. The rubber layer is located within the sealing groove, and the wear-resistant layer 3 contacts the piston rod. The rubber layer provides preload to the wear-resistant layer 3, pressing it against the piston rod. The lip structure of the wear-resistant layer 3 ensures a tight seal with the piston rod, guaranteeing its sealing performance and providing good wear resistance, thus extending the service life of the piston rod seal ring.

Claims

1. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder, characterized in that, The application relates to a wear-resistant layer, a bonding layer and an elastic layer. The inner side of the elastic layer is provided with a convex part.

2. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 1, characterized in that The thickness of the middle of the convex part is greater than the thickness of the two ends, and the thickness of the two ends is the same.

3. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 2, characterized in that The outer side of the bonding layer is provided with an inner recess part which is matched with the convex part.

4. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 3, characterized in that The inner recess part is provided with a mesh-shaped reinforcing strip.

5. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 4, characterized in that The inner side of the wear-resistant layer is provided with a cylindrical surface, a first taper surface and a second taper surface, the first taper surface is connected with the second taper surface and has opposite directions, forms a convex lip structure, and the cylindrical surface is connected with the second taper surface.

6. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 1, characterized in that, The first taper surface extends from one end of the wear-resistant layer to the other end of the wear-resistant layer to one end of the second taper surface, and the thickness gradually increases, and the second taper surface extends from one end close to the first taper surface to the other end of the wear-resistant layer to the cylindrical surface, and the thickness gradually decreases.

7. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 6, characterized in that The height ratio of the lip structure to the total height of the wear-resistant layer is 1:2-1:

4.

8. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 7, characterized in that The height ratio of the first taper surface to the second taper surface is 1:2-1:

4.

9. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 8, characterized in that The maximum thickness ratio of the lip structure to the thickness of the cylindrical surface is 1:0.5-1:

2.

10. A high pressure resistant piston rod sealing device for a pure water hydraulic cylinder according to claim 7, characterized in that, ​

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