可测量泄漏量的液压缸密封结构及液压缸
By employing a three-stage combined sealing structure in the hydraulic cylinder that allows for measurable leakage, the sealing effect can be monitored and adjusted in real time. This solves the leakage problem caused by wear of hydraulic cylinder seals, simplifies the maintenance process, reduces costs, and is suitable for harsh industrial environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIANGSU HENGLI HYDRAULIC
- Filing Date
- 2025-07-24
- Publication Date
- 2026-07-17
AI Technical Summary
Existing hydraulic cylinder sealing structures suffer from increased leakage due to seal wear after long-term use, affecting system performance. Furthermore, replacing seals is cumbersome and costly, and adjustments cannot be made based on the leakage situation.
A hydraulic cylinder sealing structure capable of measuring leakage is designed, employing a three-stage combined sealing assembly, including a V-resistance seal ring, a U-ring, and an O-ring. The leakage amount is monitored in real time through a leakage detection path, and the sealing effect can be adjusted to avoid replacing the seals.
It enables dynamic adjustment of the sealing effect during the operation of the hydraulic cylinder, simplifies the seal replacement process, reduces maintenance costs, and is suitable for harsh industrial scenarios such as tobacco leaf re-drying and food processing filter presses.
Smart Images
Figure CN224515527U_ABST
Abstract
Claims
1. A hydraulic cylinder seal structure with measurable leakage, comprising: The cylinder comprises a cylinder body, a piston rod, a guide sleeve, and a pressure cap. The cylinder body has an axially penetrating internal cavity. The piston rod is coaxially disposed within the cylinder body cavity and is axially movable. The guide sleeve is fitted around the piston rod and fixedly disposed at the end of the cylinder body. The pressure cap is connected to the guide sleeve. Its characteristic is that at least three stages of sealing structures are sequentially provided along the axial direction of the piston rod, namely: The main sealing assembly is located in the main sealing cavity formed by the piston rod and the guide sleeve, and includes a V-resist seal ring and a V-blocking ring that supports the V-resist seal ring. The axial position of the V-resist seal ring is adjustable. An intermediate sealing assembly is located in the secondary sealing cavity formed by the piston rod and the gland, and includes a U-ring A and a retaining ring A that supports the U-ring A; The rear sealing assembly is located in the buffer sealing cavity at the rear end of the secondary sealing cavity, and includes a U-ring B and a retaining ring B that supports the U-ring B. The guide sleeve has a radially arranged oil inlet and an oil outlet. The guide sleeve has an axially arranged oil outlet channel one, and the pressure cap has an axially arranged oil outlet channel two. The oil outlet, oil outlet channel one, and oil outlet channel two form a leakage detection path that runs through a three-stage sealing structure.
2. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, The sealing lip of the V-resistance sealing ring faces the high-pressure side. The V-resistance sealing ring forms an adjustable interference fit with the inner wall of the guide sleeve, and its axial compression is adjustable by the tightening of the gland.
3. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, The openings of both U-shaped rings A and B face the high-voltage side.
4. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, A slider assembly is provided between the main sealing assembly and the intermediate sealing assembly. The slider assembly includes a slider sleeved on the piston rod and a guide ring embedded in the inner cavity of the slider. The sliding surface mating with the guide sleeve and the gland is also provided with an O-ring and an O-ring retainer ring supporting the O-ring.
5. The hydraulic cylinder seal structure with measurable leakage according to claim 4, wherein The O-ring and O-ring retainer form an oil drain gap with the inner wall of the gland, and this gap is connected to the leak detection passage.
6. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, The guide sleeve is fitted around the outer periphery of the piston rod via a sliding bushing, and the sliding bushing and the piston rod form a sliding pair.
7. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein The pressure cap is threadedly connected to the guide sleeve, and the front end of the pressure cap is provided with an anti-loosening nut.
8. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, The piston rod is equipped with a dustproof component, which includes a felt and a dustproof ring arranged in sequence.
9. The hydraulic cylinder seal structure with measurable leakage according to claim 1, wherein, The leakage detection pathway includes: Leakage path of main seal: High-pressure oil seeps into the main seal cavity through the gap between the V-resistance seal ring and the piston rod, and flows to the oil discharge port through the oil discharge channel; Secondary seal leakage path: Residual oil enters the secondary seal cavity through the gap between U-ring A and piston rod, and flows into unloading channel one through unloading channel two; Leakage path of buffer seal: A small amount of oil enters the buffer seal cavity through the gap between the U-ring B and the piston rod, and flows back to the oil discharge port through the oil discharge channel 2 and the oil discharge channel 1.
10. A hydraulic cylinder characterized by Includes a hydraulic cylinder sealing structure with measurable leakage as described in any one of claims 1-9.