An active sealing device for an underwater, closed volume
The active sealing device, designed with a modular liquid bladder array and a split chassis, enables real-time monitoring and dynamic adjustment of the underwater sealed cavity, solving the failure problem of traditional sealing devices in the deep-sea environment and improving the reliability and stability of the sealing system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA STATE SHIPBUILDING CORP LTD RESEARCH INSTITUTE 719
- Filing Date
- 2025-09-12
- Publication Date
- 2026-07-14
AI Technical Summary
Traditional underwater sealed cavity sealing devices are prone to failure in deep-sea environments, lack real-time monitoring and fault early warning capabilities, resulting in insufficient equipment safety and reliability. Furthermore, the failure modes of single-unit sealing devices are prone to expansion, affecting the safe operation of the equipment.
It adopts a modular elastic liquid bladder array and a split chassis passage design, combined with hydraulic sensors and flow control valves, to achieve real-time monitoring and dynamic adjustment of the sealing status. Through active water injection and air pressure regulation of the liquid bladder group, a continuous sealing surface is formed, which enhances the sealing stability and reliability.
It effectively isolates the risk of local failure, prevents the propagation of faults, improves the redundancy and reliability of the sealing system, adapts to the long-term stable sealing requirements in the deep-sea environment, and improves equipment safety and operating efficiency.
Smart Images
Figure CN120819634B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of underwater sealing structure design technology, and specifically to a sealing device for underwater cavities. Background Technology
[0002] In the field of marine engineering, underwater sealed cavities are key components of equipment such as deep-sea probes, underwater robots, and subsea pipeline connection devices, and their sealing performance directly affects the reliability and safety of the equipment. In deep-water operating environments, due to the significant increase in external seawater pressure with depth, a large pressure difference easily forms between the inside and outside of the cavity. Traditional passive sealing devices rely on material deformation or friction to achieve a sealing effect, lacking the ability to monitor the sealing status and environmental pressure difference in real time. This makes it difficult to predict sealing failures, posing a risk of sudden equipment damage. Once a single-unit sealing device experiences a partial failure (such as material fatigue, wear, or cracks), its failure mode can easily propagate along the sealing path, causing a sharp drop in overall sealing performance and threatening the safe operation of the equipment.
[0003] As marine engineering equipment develops towards deep-sea and intelligent directions, the problem of insufficient adaptability of traditional sealing technology has become increasingly prominent. It is difficult to meet the requirements of high reliability and long service life, and it has shortcomings in real-time performance, durability and fault tolerance, which limits the application scope of underwater sealed cavities in deep-water operations.
[0004] Therefore, developing a sealing device with active adjustment function, split structure design and adaptability to various working conditions can effectively improve the controllability of sealing performance, thereby meeting the higher requirements of marine engineering equipment for safety and efficiency in deep-water operations. Summary of the Invention
[0005] In view of this, the present invention provides an active sealing device for underwater sealed cavities. Through the synergistic effect of modular sealing units, it can realize independent pressure detection and adjustment of blocks. The multi-layer liquid bladder array significantly improves the redundancy and reliability of the sealing system, effectively overcomes the failure propagation defects of traditional single-unit sealing structures, and is suitable for long-term stable sealing requirements in deep-sea environments.
[0006] An active sealing device for an underwater sealed cavity includes an adaptive sealing assembly and a cavity pressure regulating system; the adaptive sealing assembly includes an array of elastic liquid bladders, a flexible sealing strip, a sealing ring, and a pressure regulating system disposed on its top. A sealing ring is used; the adaptive sealing assembly is installed between the cavity body and the cavity cover of the sealed cavity; when the pressure of the liquid bladders in the elastic liquid bladder array is lower than a set threshold, the air pressure regulating pipeline in the cavity pressure regulating system indirectly increases the water injection pressure of the liquid bladders through a pressure compensator. The elastic liquid bladder array expands in volume by injecting fluid medium (such as seawater or pressure-resistant liquid), driving the sealing ring to move axially, so that... The shaped sealing ring and the cavity cover form an interference fit and establish a sealing interface.
[0007] Furthermore, the elastic liquid bladder array includes multiple liquid bladder groups and a chassis. Each liquid bladder group consists of three different arrangement patterns of liquid bladders arranged repeatedly. Each liquid bladder group contains nine hexagonal liquid bladders distributed in the outer, middle, and inner layers. The hexagonal liquid bladders expand after being filled with water, seamlessly fitting with adjacent liquid bladder groups to form a continuous sealing surface. The chassis includes a chassis base and a chassis shell. The chassis base is fixedly installed on the cavity of the sealed chamber, and a liquid bladder group inlet is provided below it. The liquid bladder group inlet is connected to the water inlet pipe of the cavity. The chassis shell is installed above the chassis base in a nested manner, and multiple liquid bladder injection ports are provided on its top for injecting fluid into the bottom of the liquid bladders. The liquid bladder group inlet and the liquid bladder injection port are connected through a chassis passage, which is formed by the merging of semi-circular channels on the contact surface of the chassis base and the chassis shell, ensuring that the fluid is evenly distributed to each liquid bladder group.
[0008] Furthermore, the chassis passage adopts a split processing technology, and the complete passage is achieved by assembling the chassis base and the chassis shell; each chassis passage is equipped with a flow control valve to adjust the water injection rate of the outer and inner liquid bladders, and a hydraulic sensor is provided at the end of the passage to monitor the pressure change of the liquid bladder group in real time, providing feedback data for dynamic adjustment of sealing performance.
[0009] Furthermore, a flexible sealing membrane is provided between the outer layer and the middle layer, and between the middle layer and the inner layer of the hexagonal elastic liquid bladder array. The bottom of the flexible sealing membrane is fixedly installed on the chassis shell, and the top is connected to the sealing ring. The flexible sealing membrane deforms synchronously when the liquid bladder expands, which enhances the sealing stability between the liquid bladder assembly and the sealing ring, and at the same time prevents fluid leakage between the liquid bladders.
[0010] Furthermore, each group of liquid bladders in the hexagonal elastic liquid bladder array corresponds to a liquid bladder group inlet on the chassis base. This inlet is connected to four liquid bladder injection ports via two chassis passages, ultimately achieving synchronous water injection into the nine hexagonal liquid bladders. After water injection, the axial force generated by the expansion of the liquid bladders pushes the sealing ring towards the cavity cover, thus... The O-ring fits tightly against the surface of the cavity cover, forming an interference-fit sealing interface.
[0011] Furthermore, the coordinated operation of the adaptive sealing assembly and the cavity pressure regulation system achieves dynamic balance of pressure inside and outside the sealed cavity and active adjustment of sealing performance. Initially, the liquid bladder assembly is unfilled and in a relaxed state, with no interference fit between the sealing ring and the cavity cover. When a pressure difference occurs inside and outside the cavity, the hydraulic sensor detects the pressure change in the liquid bladder assembly, and the signal is transmitted to the control system, triggering the opening of the seawater inlet in the liquid bladder pressure regulation branch. Seawater enters the liquid bladder assembly, pushing the elastic hexagonal liquid bladder array to expand and adhere to adjacent liquid bladders, forming a continuous sealing surface. The axial force generated by the expansion of the liquid bladders drives the sealing ring to move axially along the cavity, causing... The sealing ring fits tightly against the surface of the cavity cover, establishing an interference-sealed interface. The cavity pressure regulation system further optimizes the sealing effect through the linkage of the air pressure regulation pipeline and the water pressure regulation path. The air compressor in the air pressure regulation pipeline delivers gas to or discharges from the air storage chamber, and the pressure compensator transmits the air pressure change to the water pressure regulation path. The end of the liquid bladder pressure regulating branch is connected to the pressure compensator. When the pressure of the liquid bladder group is lower than the set threshold, the air pressure regulation pipeline indirectly increases the water injection pressure of the liquid bladder through the pressure compensator. The water storage chamber pressure regulating branch of the water pressure regulation path actively injects or discharges seawater through a water pump to regulate the water pressure difference inside and outside the cavity. The flexible sealing membrane in the liquid bladder group deforms synchronously during the expansion process, enhancing the sealing stability between the liquid bladder and the sealing ring and preventing fluid leakage.
[0012] Beneficial effects:
[0013] 1. This invention utilizes a modular elastic liquid bladder array and a split chassis passage design. By combining a ring-shaped multi-layer liquid bladder assembly with a split manufacturing process, the unitized liquid bladder assembly design can effectively isolate the risk of local failure and prevent the fault from propagating to the entire sealing system. The chassis is composed of a chassis base and a chassis shell nested together. The split chassis structure facilitates processing and maintenance, and supports independent module replacement, significantly improving system reliability and maintenance efficiency.
[0014] 2. The active water injection and flow control mechanism of the liquid bladder assembly in this invention can dynamically adjust the displacement of the sealing ring. The synergistic effect of air pressure regulation and seawater injection enables the pressure compensator to automatically match external water pressure fluctuations, avoiding failure of the sealing interface due to pressure imbalance. The synchronous deformation of the flexible sealing membrane further enhances the overall sealing stability of the liquid bladder assembly.
[0015] 3. This invention improves the intelligence and reliability of the device by integrating hydraulic sensors and flow control valves. By monitoring the pressure gradient of the liquid bladder in real time, it can intervene in advance to prevent local failure risks. The modular liquid bladder group design supports fault isolation and rapid response, ensuring the long-term stable operation of the deep-water sealed cavity. It solves the problems of failure propagation, difficulty in reliability prediction, and insufficient adaptability of traditional sealing devices in deep-water environments. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention;
[0017] Figure 2 This is a schematic diagram of the sealing structure;
[0018] Figure 3 This is a diagram showing the arrangement of a hexagonal liquid bladder array;
[0019] Figure 4 This is a schematic diagram of the sealing assembly structure;
[0020] Figure 5 This is a schematic diagram of the base plate and the outer shell;
[0021] Figure 6 This is one of the diagrams showing the arrangement of the liquid bladder group;
[0022] Figure 7 This is the second diagram showing the arrangement of the liquid bladder group;
[0023] Figure 8 This is the third diagram showing the arrangement of the liquid bladder group.
[0024] Wherein, 1-first speed regulating valve; 2-pressure compensator; 3-second speed regulating valve; 4-seawater inlet; 5-filter; 6-first check valve; 7-first solenoid valve; 8-first water pump; 9-first flow meter; 10-second solenoid valve; 11-cavity; 12-sealing assembly; 1201- 1202-Sealing ring; 1203-Hexagonal liquid bladder; 1204-Flexible sealing strip; 1205-Liquid bladder water inlet; 1206-Liquid bladder assembly water inlet; 1207-Chassis base; 1208-Chassis shell; 1209-Chassis passage; 13-Cavity cover; 14-Partition; 15-Third solenoid valve; 16-Second water pump; 17-Fourth solenoid valve; 18-Second flow meter; 19-Third water pump; 20-Fifth solenoid valve; 21-Fourth water pump; 22-Third speed control valve; 23-Sixth solenoid valve; 24-Gas tank; 25-Second check valve; 26-Air compressor; 27-Hydraulic sensor; 28-Flow control valve; 29-Seawater outlet. Detailed Implementation
[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0026] As attached Figure 1 , 2 As shown in Figure 3, the present invention provides an active sealing device for an underwater sealed cavity, including an adaptive sealing assembly and a cavity pressure regulating system; the adaptive sealing assembly includes an array of elastic liquid bladders composed of hexagonal liquid bladders, a flexible sealing strip 1204, a sealing ring 1202, and a sealing ring disposed on its top. A sealing ring 1201 is used; an adaptive sealing assembly is installed between the cavity 11 and the cavity cover 13 of the sealed cavity. The cavity is the entire underwater chamber, which is internally separated by a partition 14, with an air storage chamber below and a water storage chamber above. The water storage chamber contains seawater, while the air storage chamber does not contain seawater and relies solely on an air compressor and high-pressure gas to balance the pressure.
[0027] The elastic fluid-filled bladder array comprises multiple bladder groups and a chassis. Each bladder group consists of three different arrangements of bladders arranged repeatedly to form an outer, middle, and inner three-layered hexagonal ring array. These three arrangements correspond to three basic units, as shown in the attached diagram. Figure 6 , 7 As shown in Figure 8, when multiple basic units are combined, the liquid bladders at the contact positions are matched end to end to avoid uneven pressure caused by end to end or end to end. Each liquid bladder group contains nine hexagonal liquid bladders. After water is injected, the hexagonal liquid bladders expand and fit seamlessly with the adjacent liquid bladder groups to form a continuous sealing surface.
[0028] As attached Figure 4 As shown, the chassis includes a chassis base 1207 and a chassis shell 1208. The chassis base 1207 is fixedly installed on the cavity 11 of the sealed chamber, and a liquid bladder assembly inlet 1206 is provided below it. The liquid bladder assembly inlet 1206 is connected to the water inlet pipe of the cavity 11. The chassis shell 1208 is installed above the chassis base 1207 in a nested manner, and nine liquid bladder injection ports 1205 are provided on its top for injecting fluid into the bottom of the liquid bladders. The liquid bladder assembly inlet 1206 and the liquid bladder injection ports 1205 are connected through a chassis passage 1209. The chassis passage 1209 is formed by the merging of semi-circular channels on the contact surface of the chassis base 1207 and the chassis shell 1208, ensuring that the fluid is evenly distributed to each liquid bladder assembly, as shown in the attached figure. Figure 5 As shown, the chassis shell 1208 is in a semi-sectional state. Except for the liquid bladder inlet 1206, the hexagonal grooves at other locations do not penetrate the chassis base 1207. When the chassis shell 1208 and the chassis base 1207 are engaged, except for the liquid bladder inlet 1205 directly above the liquid bladder inlet 1206, the other eight liquid bladder inlets are connected to the liquid bladder inlet 1206 via the chassis passage 1209.
[0029] The active sealing device achieves active control of the sealing interface by dynamically adjusting the water injection state of the hexagonal liquid bladder 1203. Its operation is coordinated with the cavity pressure regulation system to maintain pressure balance inside and outside the sealed cavity. Initially, the liquid bladder 1203 is in an uninjected state, and the array of hexagonal liquid bladders 1203 remains relaxed on the chassis housing 1208. The sealing ring 1202 and... The sealing ring 1201 does not form an interference fit with the cavity cover 11, and the internal pressure of the cavity is initially balanced with the external seawater pressure. The hydraulic sensor 27 monitors the pressure of the liquid bladder group in real time and uses it as a reference value.
[0030] When a sealed cavity is required, the control system initiates the water injection process of the liquid bladder pressure regulating branch. The inlet end of the liquid bladder pressure regulating branch is connected to the seawater inlet 4, and sequentially integrates a filter 5, a first one-way valve 6, and a first solenoid valve 7. The filter 5 is used to remove impurities and protect downstream components. The first one-way valve 6 prevents backflow of liquid. The first solenoid valve 7 actively opens and closes based on the pressure signal of the liquid bladder 1203 fed back by the hydraulic sensor 27, precisely controlling the amount of seawater injected. After seawater is injected into the liquid bladder 1203, the elastic hexagonal liquid bladders 1203 array expands, increasing in volume and fitting adjacent hexagonal liquid bladders 1203 to form a continuous sealing surface. The axial force generated by the expansion pushes the sealing ring 1202 to move axially along the cavity, making... The O-ring 1201 fits tightly against the cavity cover 11, establishing an interference-fit sealing interface.
[0031] The liquid bladder pressure regulating branch is connected to the pressure compensator 2, forming a closed-loop control through the air pressure regulating branch. When the pressure of the hexagonal liquid bladder 1203 is lower than the set threshold, the air pressure regulating pipeline inflates the pressure compensator 2 through the air compressor 26, the second one-way valve 25, the air tank 24, and the first speed regulating valve 1, indirectly increasing the pressure of the hexagonal liquid bladder 1203 through the second speed regulating valve 3. Conversely, the pressure is released by draining water through the third solenoid valve 15, the second water pump 16, and the seawater outlet 20. The water storage chamber pressure regulating branch, through the coordinated action of the water pump and the air compressor, enables the active injection or discharge of seawater into the water storage chamber, assisting in regulating the pressure difference inside and outside the chamber. The flexible sealing membrane of the liquid bladder sealing device deforms synchronously when the hexagonal liquid bladder 1203 expands, enhancing the sealing stability between the liquid bladder assembly and the sealing ring and preventing fluid leakage between the liquid bladders 1203. At the same time, the split chassis passage divides the liquid bladder assembly into independent modules, avoiding the collapse of the entire sealing structure due to the failure of a single hexagonal liquid bladder 1203.
[0032] The cavity pressure regulation system further reduces the impact of the pressure difference between the inside and outside of the cavity on the liquid bladder 1203 through active regulation of air and water pressure: When the internal pressure of the cavity is lower than that of the external environment, the air pressure regulation pipeline controls the pressure of the air storage chamber through the air compressor 26, the second one-way valve 25, the air tank 24, and the third speed regulating valve 22, and simultaneously increases the water injection pressure of the liquid bladder 1203 through the pressure compensator 2, enhancing the interference fit of the sealing interface; the first solenoid valve 7 and the second solenoid valve 10 of the liquid bladder pressure regulation branch precisely control the seawater injection volume according to real-time pressure data, increasing the pressure of the water storage chamber while ensuring that the expansion rate of the liquid bladder 1203 is synchronized with the changes in cavity pressure. When the liquid bladder group is working for a long time, the pressure of the liquid bladder group is increased by replenishing seawater, effectively reducing energy consumption. Hydraulic sensor 27 is embedded at the end of the pressure regulating branch of the liquid bladder to continuously monitor the pressure distribution of the outer, middle and inner hexagonal liquid bladders 1203. The data is uploaded to the control system. By analyzing the pressure gradient, the system determines whether there is a risk of local failure in the liquid bladder group (such as an abnormal drop in pressure of a certain layer of liquid bladders) and activates the emergency adjustment mechanism (such as directional water injection or local drainage). The system also prevents pressure leakage by closing the corresponding flow control valve 28, ensuring that the other hexagonal liquid bladders 1203 can still work normally.
[0033] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. An active sealing device for underwater sealed cavities, characterized in that, It includes an adaptive sealing assembly and a cavity pressure regulating system; the adaptive sealing assembly includes an array of elastic liquid bladders, a flexible sealing diaphragm, a sealing ring, and a component disposed on top of the sealing ring. A sealing ring is formed; the adaptive sealing assembly is installed between the cavity body and the cavity cover of the sealed cavity; when the pressure of the liquid bladders in the elastic liquid bladder array is lower than a set threshold, the air pressure regulating pipeline in the cavity pressure regulating system indirectly increases the water injection pressure of the liquid bladders through a pressure compensator, and the elastic liquid bladder array expands in volume through water injection, driving the sealing ring to move axially, so that... The sealing ring and the cavity cover form an interference fit and establish a sealing interface; The elastic liquid bladder array includes multiple bladder groups and a chassis. Each bladder group consists of three different arrangement patterns of bladders arranged repeatedly. Each bladder group contains nine hexagonal bladders distributed in three layers: outer, middle, and inner. The hexagonal bladders expand after being filled with water, seamlessly fitting with adjacent bladder groups to form a continuous sealing surface. The chassis includes a chassis base and a chassis shell. The chassis base is fixedly installed on the cavity of the sealed chamber, and a bladder group inlet is provided below it, which is connected to the water inlet pipe of the cavity. The chassis shell is installed above the chassis base in a nested manner, and multiple bladder injection ports are provided on its top for injecting fluid into the bottom of the bladders. The bladder group inlets and bladder injection ports are connected through a chassis passage, which is formed by the merging of semi-circular channels on the contact surface of the chassis base and the chassis shell, ensuring that the fluid is evenly distributed to each bladder group. The hexagonal elastic liquid bladder array has flexible sealing membranes between the outer and middle layers, and between the middle and inner layers. The bottom of the flexible sealing membrane is fixedly installed on the chassis shell, and the top is connected to the sealing ring. The flexible sealing membrane deforms synchronously when the liquid bladder expands, which enhances the sealing stability between the liquid bladder assembly and the sealing ring, and prevents fluid leakage between the liquid bladders.
2. The active sealing device for an underwater sealed cavity as described in claim 1, characterized in that, The chassis passage adopts a split processing technology, and the complete passage is achieved by assembling the chassis base and the chassis shell. Each chassis passage is equipped with a flow control valve to adjust the water injection rate of the outer and inner liquid bladders. At the same time, a hydraulic sensor is installed at the end of the passage to monitor the pressure change of the liquid bladder group in real time, providing feedback data for dynamic adjustment of sealing performance.
3. The active sealing device for an underwater sealed cavity as described in claim 2, characterized in that, Each group of liquid bladders in the hexagonal elastic liquid bladder array corresponds to a liquid bladder group inlet on the chassis base. This inlet is connected to four liquid bladder injection ports via two chassis passages, ultimately achieving synchronous water injection into the nine hexagonal liquid bladders. After water injection, the axial force generated by the expansion of the liquid bladders pushes the sealing ring towards the cavity cover, thus... The O-ring fits tightly against the surface of the cavity cover, forming an interference-fit sealing interface.
4. The active sealing device for an underwater sealed cavity as described in claim 3, characterized in that, The adaptive sealing assembly and the cavity pressure regulation system work together to achieve dynamic balance of pressure inside and outside the sealed cavity and active adjustment of sealing performance. Initially, the liquid bladder assembly is unfilled and in a relaxed state, with no interference fit between the sealing ring and the cavity cover. When a pressure difference occurs inside and outside the cavity, the hydraulic sensor detects the pressure change in the liquid bladder assembly and transmits the signal to the control system, triggering the opening of the seawater inlet in the liquid bladder pressure regulation branch. Seawater enters the liquid bladder assembly, pushing the elastic hexagonal liquid bladder array to expand and adhere to adjacent liquid bladders, forming a continuous sealing surface. The axial force generated by the expansion of the liquid bladders drives the sealing ring to move axially along the cavity, causing... The sealing ring fits tightly against the surface of the cavity cover, establishing an interference-sealed interface. The cavity pressure regulation system further optimizes the sealing effect through the linkage of the air pressure regulation pipeline and the water pressure regulation path. The air compressor in the air pressure regulation pipeline delivers gas to or discharges from the air storage chamber, and the pressure compensator transmits the air pressure change to the water pressure regulation path. The end of the liquid bladder pressure regulating branch is connected to the pressure compensator. When the pressure of the liquid bladder group is lower than the set threshold, the air pressure regulation pipeline indirectly increases the water injection pressure of the liquid bladder through the pressure compensator. The water storage chamber pressure regulating branch of the water pressure regulation path actively injects or discharges seawater through a water pump to regulate the water pressure difference inside and outside the cavity. The flexible sealing membrane in the liquid bladder group deforms synchronously during the expansion process, enhancing the sealing stability between the liquid bladder and the sealing ring and preventing fluid leakage.