Large-gap piston sealing structure of hydraulic cylinder

Abstract

The utility model provides a hydraulic cylinder large-gap piston sealing structure which comprises a piston and a cylinder barrel, and the piston is matched with the cylinder barrel. A piston seal, a check ring and a guide ring are arranged on the piston, the piston seal, the check ring and the guide ring are arranged on the side close to the cylinder barrel, the piston seal comprises an O-shaped ring sealing piece and a square sealing piece, the check ring is arranged close to the piston seal, and the guide ring is arranged close to the check ring; the check rings made of high-strength materials are arranged on the two sides of the piston seal to make up gaps so as to prevent the piston seal from being squeezed into the gaps to be damaged under high pressure, and the service life of the piston sealing structure is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of sealing structures, in particular to a large-clearance piston sealing structure of a hydraulic cylinder. Background Art

[0002] The hydraulic cylinder is an important actuator of the hydraulic system. If internal leakage occurs, the working medium flow inside the hydraulic cylinder will be insufficient, resulting in reduced system efficiency and affecting the normal operation of the equipment.

[0003] Internal leakage can be caused by hydraulic cylinder overload or excessive side loads, piston seal extrusion damage, and piston damage to the cylinder bore. To prevent direct contact and friction between the piston and the cylinder, hydraulic cylinders are typically designed with a clearance fit and a piston seal. However, under extreme operating conditions (hydraulic shock or high side loads), a large gap can occur, forcing the piston seal into the gap and causing damage, leading to internal leakage. Utility Model Content

[0004] The purpose of the utility model is to solve the above problems and provide a large-gap piston seal structure for a hydraulic cylinder. By arranging high-strength material retaining rings on both sides of the piston seal, the gap is filled to prevent the piston seal from being squeezed into the gap and damaged under high pressure, thereby improving the service life of the piston seal structure.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions.

[0006] A large-clearance piston sealing structure of a hydraulic cylinder includes a piston and a cylinder barrel, wherein the piston cooperates with the cylinder barrel; a piston seal, a retaining ring and a guide ring are provided on the piston, wherein the piston seal, the retaining ring and the guide ring are arranged on a side close to the cylinder barrel, and the piston seal includes an O-ring seal and a square seal, wherein the retaining ring is arranged close to the piston seal, and the guide ring is arranged close to the retaining ring.

[0007] Furthermore, the guide ring is arranged away from the piston seal.

[0008] Furthermore, the O-ring seal is arranged away from the retaining ring.

[0009] Furthermore, two retaining rings are provided.

[0010] Furthermore, two guide rings are provided.

[0011] Furthermore, the guide ring is made of phenolic cloth.

[0012] Furthermore, the retaining ring is made of modified polyoxymethylene.

[0013] Furthermore, the retaining ring is made of nylon.

[0014] The positive effects of the large-clearance piston sealing structure of a hydraulic cylinder of the utility model are:

[0015] When there is a large lateral load on the hydraulic cylinder and a larger gap must be designed between the piston and the cylinder, high-strength retaining rings are installed on both sides of the piston seal to fill the gap and prevent the piston seal from being squeezed into the gap and damaged under high pressure, effectively avoiding the risk of the cylinder bore being strained; the guide ring is made of phenolic cloth-reinforced material, which has high dynamic compression strength, good heat resistance and wear resistance, strong guiding support, and improves the service life of the sealing structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram provided by an embodiment of the present utility model.

[0017] The numbers in the figure are:

[0018] 1. Piston; 2. Piston seal; 3. Retaining ring; 4. Guide ring; 5. Cylinder barrel. DETAILED DESCRIPTION

[0019] The following is a specific implementation of a large-clearance piston sealing structure for a hydraulic cylinder of the present invention, in conjunction with the accompanying drawings. However, it should be noted that the specific implementation is not intended to limit the specific implementation of the present invention. All similar structures and similar variations of the present invention should be included in the scope of protection of the present invention. The following descriptions of the embodiments are with reference to the attached drawings to illustrate specific embodiments in which the present invention can be implemented. The directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", "top", "bottom", etc., are only with reference to the directions of the attached drawings. Therefore, the directional terms used are used to illustrate and understand the present invention, rather than to limit the present invention.

[0020] See also Figure 1 A large-clearance piston seal 2 structure for a hydraulic cylinder includes a piston 1 and a cylinder barrel 5, wherein the piston 1 cooperates with the cylinder barrel 5; a piston seal 2, a retaining ring 3, and a guide ring 4 are provided on the piston 1, wherein the piston seal 2, the retaining ring 3, and the guide ring 4 are arranged on a side close to the cylinder barrel 5; the piston seal 2 includes an O-ring seal and a square seal, wherein the retaining ring 3 is arranged close to the piston seal 2, and the guide ring 4 is arranged close to the retaining ring 3. The guide ring 4 is arranged away from the piston seal 2. The O-ring seal is arranged away from the retaining ring 3.

[0021] A piston seal groove is provided on piston 1. The piston seal groove matches the size of piston seal 2. Piston seal 2 includes an O-ring seal and a square seal. In the figure, the O-ring seal is located below the square seal. The diameter of the O-ring seal is smaller than that of the square seal.

[0022] Piston 1 is provided with a retaining ring groove that matches the dimensions of retaining ring 3. Two retaining rings 3 are provided, one on the left and one on the right side of piston seal 2 as shown. Retaining rings 3 are made of modified polyoxymethylene or nylon to prevent piston seal 2 from being squeezed into the gap and damaged under high pressure.

[0023] Piston 1 is provided with a guide ring groove, which is sized to match guide ring 4. Two guide rings 4 are provided, one on the left and one on the right side of piston seal 2 and retaining ring 3. The guide rings 4 are constructed of phenolic fabric sandwich panels, offering high dynamic compression strength, excellent heat and wear resistance, and provide precise guidance and support for the hydraulic cylinder.

[0024] During installation of the large-gap piston seal 2 in a hydraulic cylinder, the piston seal 2 is installed in the piston seal groove, the guide ring 4 is installed in the guide ring groove, and the retaining rings 3 are installed in the retaining ring grooves on both sides of the piston seal 2. The piston 1 is then completely installed in the cylinder barrel 5. The guide rings 4 are positioned between the piston 1 and the cylinder barrel 5 to prevent direct contact and friction between the two, and provide support and guidance during the reciprocating motion of the hydraulic cylinder. When the piston 1 is subjected to large side loads or high pressure, the retaining rings 3 fill the gap between the piston 1 and the cylinder barrel 5, preventing the piston seal 2 from being squeezed into the gap and causing seal damage.

[0025] When there is a large lateral load on the hydraulic cylinder and a large gap must be designed between the piston 1 and the cylinder 5, a high-strength material retaining ring 3 is set on both sides of the piston seal 2 to fill the gap and prevent the piston seal 2 from being squeezed into the gap and damaged under high pressure, effectively avoiding the risk of the inner hole of the cylinder 5 being strained; the guide ring 4 is made of phenolic cloth-reinforced material, which has high dynamic compression strength, good heat resistance and wear resistance, strong guiding support, and improves the service life of the sealing structure.

Claims

1. A large clearance piston sealing structure for a hydraulic cylinder, characterized in that: The invention comprises a piston and a cylinder, wherein the piston cooperates with the cylinder; a piston seal, a retaining ring and a guide ring are provided on the piston, wherein the piston seal, the retaining ring and the guide ring are arranged on a side close to the cylinder, and the piston seal comprises an O-ring seal and a square seal, wherein the retaining ring is arranged close to the piston seal, the guide ring is arranged close to the retaining ring, the guide ring is arranged away from the piston seal, and the O-ring seal is arranged away from the retaining ring. Two retaining rings are provided, and two guide rings are provided. The guide ring adopts a phenolic cloth-cladded part, the retaining ring adopts a modified polyformaldehyde part, and the retaining ring adopts a nylon part. The piston is provided with a piston sealing groove, and the piston sealing groove matches the size of the piston seal; The piston is provided with a retaining ring groove, and the retaining ring groove matches the size of the retaining ring; A guide ring groove is provided on the piston, and the guide ring groove matches the size of the guide ring.

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