A hydraulic cylinder with a piston with an end face seal
Patent Information
- Application Number
- CN202522314463.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-31
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-10-31
AI Technical Summary
[0004]为了克服上述现有技术的不足之处，本实用新型提供本实用新型的目的在于克服现有技术中液压缸静密封结构单一、易装切且内泄风险高的不足，提供一种活塞带端面密封的液压缸，通过优化密封结构设计，实现双重静密封保压效果，提升油缸密封性能和可靠性
[0010]本实用新型的有益效果是：密封性能优异：通过活塞杆静密封与端面静密封构成的双重静密封结构，显著提高了静密封的密封效果，即使其中一道静密封失效，另一道静密封仍能保证油缸密封性能，尤其适用于高压高频使用工况。
Smart Images
Figure CN224835643U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of hydraulic cylinder technology, specifically to a hydraulic cylinder with a piston and end face seal. Background Technology
[0002] With the continuous development of the hydraulic industry, the application range of hydraulic cylinders is becoming increasingly wide, design requirements are showing a diversified trend, and operating conditions are becoming increasingly complex, which places higher demands on the reliability and stability of hydraulic cylinders. Among the various failure modes of hydraulic cylinders, internal leakage is the most common problem, and the failure of the static seal between the piston and piston rod is one of the main causes of internal leakage. Therefore, ensuring the high reliability of the static seal between the piston and piston rod has become a key aspect of hydraulic cylinder design.
[0003] In existing technologies, the static seals of pistons and piston rods are primarily either piston static seals or piston rod static seals, without employing end-face seals between the piston and piston rod. This single static seal structure has significant drawbacks: static seals are highly susceptible to breakage during assembly, and because factory testing is typically brief, these issues are difficult to identify promptly. In practical applications, internal leakage caused by static seal failure often only becomes apparent after the main unit has been in use for a period of time. This not only affects the normal operation of the equipment but also leads to significant customer complaints and economic losses due to downtime and repairs. Utility Model Content
[0004] In order to overcome the shortcomings of the prior art, the present invention aims to overcome the shortcomings of the existing hydraulic cylinder static sealing structure being simple, easy to install and cut, and having a high risk of internal leakage. It provides a hydraulic cylinder with piston end face sealing, which achieves a double static sealing pressure holding effect by optimizing the sealing structure design, thereby improving the sealing performance and reliability of the cylinder.
[0005] This utility model is achieved through the following technical solution: a hydraulic cylinder with a piston and an end face seal, comprising a piston, a support ring, a main seal, a piston rod static sealing groove, an end face static sealing groove, a piston rod, and a cylinder barrel; the piston and piston rod mating end faces are provided with the end face static sealing groove, and an O-ring is adapted to be installed in the end face static sealing groove; a dynamic sealing structure composed of the support ring and the main seal is provided between the piston and the cylinder barrel, and a static sealing structure composed of the piston rod static sealing groove and the end face static sealing groove.
[0006] Furthermore, the piston rod static sealing groove and the end face static sealing groove form a double static seal, which together seals the large and small cavities of the oil cylinder.
[0007] Furthermore, when the piston and the piston rod are connected by threads, and the difference between the thread diameter and the mating stop diameter is small, the O-ring in the static sealing groove of the end face can still achieve effective sealing.
[0008] Furthermore, the O-ring is made of oil-resistant rubber, and the cross-sectional diameter of the O-ring is adapted to the width and depth of the static sealing groove on the end face.
[0009] Furthermore, the outer circumferential surface of the piston is provided with an annular groove for installing the support ring and the main seal, and the support ring and the main seal are arranged sequentially along the axial direction of the piston.
[0010] The beneficial effects of this utility model are: excellent sealing performance: the double static sealing structure formed by the piston rod static seal and the end face static seal significantly improves the sealing effect of the static seal. Even if one static seal fails, the other static seal can still ensure the sealing performance of the cylinder, which is especially suitable for high-pressure and high-frequency operating conditions.
[0011] Easy assembly and no cutting risk: The static sealing groove design on the end face of the piston and piston rod makes the assembly process simple and avoids the problem of easy cutting of traditional static seals, thus avoiding the risk of internal leakage due to cutting.
[0012] Compact structure: The opening of the static sealing groove on the end face does not require increasing the total length of the piston, ensuring the overall compactness of the hydraulic cylinder structure and meeting the installation space requirements in different scenarios. Attached Figure Description
[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0014] Figure 1 This is a schematic diagram of the structure of this utility model; In the diagram: 1-piston, 2-support ring, 3-main seal, 4-piston rod static seal groove, 5-end face static seal groove, 6-piston rod, 7-cylinder. Detailed Implementation
[0015] like Figure 1 The hydraulic cylinder shown is a piston with an end-face seal, mainly composed of a piston 1, a support ring 2, a main seal 3, a piston rod static sealing groove 4, an end-face static sealing groove 5, a piston rod 6, and a cylinder 7. The piston 1 and piston rod 6 are connected by threads, and an end-face static sealing groove 5 is specially designed on their mating end faces. An O-ring is installed in this groove to achieve the end-face static sealing function. Between the piston 1 and the cylinder 7, on the one hand, a dynamic sealing structure is formed by the support ring 2 and the main seal 3 to ensure the sealing effect when the piston reciprocates within the cylinder; on the other hand, a double static sealing structure is formed by the piston rod static sealing groove 4 and the end-face static sealing groove 5, creating a double sealing barrier.
[0016] In actual operation, when the hydraulic cylinder is under high-pressure and high-frequency use, if the static seal at the piston rod static seal groove 4 fails, the O-ring in the end face static seal groove 5 can still effectively block the flow of media between the large and small chambers of the cylinder, preventing internal leakage and ensuring normal operation of the cylinder. Furthermore, since the end face static seal groove 5 is located on the mating end face of the piston and piston rod, there is no need to increase the overall length of the piston 1, making the overall structure of the hydraulic cylinder compact. At the same time, during assembly, the end face seal structure is less prone to cutting during assembly, solving the hidden danger of traditional static seal cutting problems that are difficult to identify during factory testing, further improving the reliability of the cylinder.
[0017] This invention creates a double static seal structure by adding a static sealing groove to the mating end face of the piston and piston rod and using an O-ring. Without increasing the piston size and ensuring a compact structure, it significantly improves the sealing performance and reliability of the hydraulic cylinder, effectively reduces the risk of internal leakage due to static seal failure, and avoids economic losses caused by downtime and repairs. It is suitable for various single-acting or double-acting piston structures and double-acting hydraulic cylinders with high sealing performance requirements.
Claims
1. A hydraulic cylinder with a piston and an end face seal, characterized in that: The system includes a piston (1), a support ring (2), a main seal (3), a piston rod static sealing groove (4), an end face static sealing groove (5), a piston rod (6), and a cylinder (7). The piston (1) and the piston rod (6) have the end face static sealing groove (5) on their mating end faces, and an O-ring is fitted inside the end face static sealing groove (5). A dynamic sealing structure composed of the support ring (2) and the main seal (3) is provided between the piston (1) and the cylinder (7), as well as a static sealing structure composed of the piston rod static sealing groove (4) and the end face static sealing groove (5).
2. A hydraulic cylinder with a piston and end face seal according to claim 1, characterized in that, The piston rod static sealing groove (4) and the end face static sealing groove (5) form a double static seal, which together seal the large and small cavities of the oil cylinder.
3. A hydraulic cylinder with a piston and end face seal according to claim 1, characterized in that, When the piston (1) and the piston rod (6) are connected by threads, and the difference between the thread and the diameter of the mating stop is small, the O-ring in the static sealing groove (5) on the end face can still achieve effective sealing.
4. A hydraulic cylinder with a piston and end face seal according to claim 1, characterized in that, The O-ring is made of oil-resistant rubber, and the cross-sectional diameter of the O-ring is adapted to the width and depth of the end face static sealing groove (5).
5. A hydraulic cylinder with a piston and end face seal according to claim 1, characterized in that, The piston (1) has an annular groove on its outer circumferential surface for installing the support ring (2) and the main seal (3). The support ring (2) and the main seal (3) are arranged sequentially along the axial direction of the piston (1).