Buoyancy adjustment device for underwater vehicle

Abstract

A buoyancy adjustment device for an underwater vehicle, comprising a pressure-resistant cabin body, an assembly part is arranged on the outer side of the pressure-resistant cabin body, and an air bag and a liquid bag are installed on the assembly part; a hydraulic control unit, a pneumatic control unit and an oil tank are installed in the pressure-resistant cabin body; the hydraulic control unit is respectively communicated with the liquid bag and the oil tank to enable the oil liquid to flow between the liquid bag and the oil tank; the pneumatic control unit is respectively communicated with the air bag and the pressure-resistant cabin body to enable the gas to flow between the air bag and the pressure-resistant cabin body; the outer periphery of the liquid bag and the outer periphery of the air bag are both fixed on the assembly part, and the liquid bag wraps the air bag, so as to form a pneumatic cabin located between the air bag and the assembly part and a hydraulic cabin located between the air bag and the liquid bag. In the embodiment of the present invention, by arranging the air bag and the liquid bag, the form of buoyancy adjustment is more diversified, and compared with sucking and discharging seawater to change the self-weight, the energy consumption is less, there is no limitation, and the buoyancy can be adjusted larger or smaller; the air bag is nested in the liquid bag, which can reduce the occupation of the installation space and can be quickly emptied.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater robots, and particularly relates to a buoyancy adjustment device for an underwater vehicle. Background Art

[0002] An unmanned underwater vehicle is an underwater observation and detection platform, which has been widely used in the fields of marine scientific research and military detection. The buoyancy adjustment device is one of the core functional units of an underwater vehicle, and its performance directly affects the overall performance of the underwater vehicle. Since the density of seawater increases with the increase of depth, when an underwater vehicle dives or floats, it usually needs to adjust its own buoyancy.

[0003] Currently, small underwater vehicles usually use the method of discharging and sucking back oil to change their own volume size to achieve the purpose of adjusting buoyancy. This method has a single adjustment form; large underwater vehicles such as submarines usually use the method of sucking and discharging seawater to change their own gravity to achieve the purpose of diving and floating. This method is not applicable to small underwater vehicles and has disadvantages such as poor reliability, low efficiency, and high energy consumption; there are also some underwater vehicles that reduce their own weight by discarding some heavy objects to achieve the floating action. This method can only achieve floating and cannot achieve diving, with strong limitations. In summary, from the perspective of the prior art, the underwater buoyancy adjustment device has disadvantages such as a single adjustment form, large energy consumption, and strong limitations, and urgently needs to be solved by new technical means or invented devices. Summary of the Invention

[0004] In view of the deficiencies in the related art, the present invention provides a buoyancy adjustment device for an underwater vehicle to solve the problems of the current buoyancy adjustment device with a single form, large energy consumption, and strong limitations.

[0005] The present invention provides a buoyancy adjustment device for an underwater vehicle, including a pressure-resistant cabin body. An assembly part is arranged on the outer side of the pressure-resistant cabin body, and an airbag and a liquid bag are installed on the assembly part;

[0006] A hydraulic control unit, a pneumatic control unit, and an oil tank are installed in the pressure-resistant cabin body;

[0007] The hydraulic control unit is respectively connected to the liquid bag and the oil tank to enable the oil to flow between the liquid bag and the oil tank;

[0008] The pneumatic control unit is respectively connected to the airbag and the pressure-resistant cabin body to enable the gas to flow between the airbag and the pressure-resistant cabin body;

[0009] The outer periphery of the liquid bag and the outer periphery of the airbag are both fixed on the assembly part, and the liquid bag wraps the airbag, thereby forming a pneumatic cabin located between the airbag and the assembly part and a hydraulic cabin located between the airbag and the liquid bag.

[0010] In some of these embodiments, the airbag extends its interior through an opening formed in the outer periphery of the liquid sac, and a sealing flange arranged in a ring shape is pressed and fixed on the assembly part through an annular fixing member.

[0011] In some of these embodiments, a flow deflector is installed on the assembly part. The flow deflector has a communication port that can allow liquid to enter and exit, and sleeves the liquid sac.

[0012] The fixing member is a fixing flange provided for the flow deflector. The fixing flange is installed on the assembly part and presses the sealing flange.

[0013] In some of these embodiments, the flow deflector is cylindrical, and the communication port is the port at the outer end of the flow deflector.

[0014] In some of these embodiments, the assembly part presses and fixes the outer periphery of the airbag on the assembly part through a pressing ring installed. The outer periphery of the airbag has a sealing ring, and the sealing ring is pressed and fixed in a sealing groove formed in the assembly part through the pressing ring.

[0015] In some of these embodiments, a volume increasing groove is formed on the end face of the assembly part. The airbag forms an air storage space by recessing outward. The volume increasing groove and the air storage space are symmetrically arranged to enable the airbag to adhere to the inner wall of the volume increasing groove when the pressure cabin is emptied.

[0016] In some of these embodiments, the hydraulic control unit includes a hydraulic pump, a first one-way valve, and a first solenoid valve.

[0017] The assembly part is provided with an oil passage communicating with the liquid sac. The fuel tank is respectively connected to the oil passage through an oil delivery pipeline and an oil return pipeline.

[0018] The hydraulic pump and the first one-way valve are installed on the oil delivery pipeline, and the first solenoid valve is installed on the oil return pipeline.

[0019] In some of these embodiments, the pneumatic control unit includes an air pump, a second one-way valve, and a second solenoid valve.

[0020] The assembly part is provided with a gas passage communicating with the airbag. The pressure-resistant cabin body is respectively connected to the gas passage through a gas filling pipeline and an exhaust pipeline.

[0021] The air pump and the second one-way valve are installed on the gas filling pipeline, and the second solenoid valve is installed on the exhaust pipeline.

[0022] In some of these embodiments, the airbag is provided with a closed compensation chamber filled with gas.

[0023] In some of these embodiments, the fuel tank is a bellows with both ends closed.

[0024] Based on the above technical solution, in the embodiments of the present invention, by setting the airbag and the liquid bag, buoyancy adjustment can be performed by inflating and exhausting air at low pressure, and buoyancy adjustment can be performed by filling and draining liquid at high pressure. The airbag and the liquid bag can perform buoyancy adjustment in a variety of coordinated and complementary ways, making the form of buoyancy adjustment more diverse. Compared with sucking and discharging seawater to change the self-weight, the energy consumption is less, there are no limitations, and the buoyancy can be adjusted larger or smaller. The airbag is nested in the liquid bag, which can reduce the occupation of installation space and can achieve rapid evacuation, solving the problems of the current buoyancy adjustment device with a single form, large energy consumption, and strong limitations. Brief Description of the Drawings

[0025] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0026] Figure 1 It is a cross-sectional structure diagram of the buoyancy adjustment device for the underwater vehicle of the present invention;

[0027] Figure 2 It is a schematic structural diagram of the buoyancy adjustment device for the underwater vehicle of the present invention with a part of the pressure-resistant cabin hidden and cut open Figure 1 ;

[0028] Figure 3 It is a schematic structural diagram of the buoyancy adjustment device for the underwater vehicle of the present invention with a part of the pressure-resistant cabin hidden and cut open Figure 2 ;

[0029] Figure 4 It is a system structure diagram of the hydraulic control unit and the pneumatic control unit of the buoyancy adjustment device for the underwater vehicle of the present invention.

[0030] In the figure:

[0031] 1. Pressure-resistant cabin; 11. Assembly part; 12. Compression ring; 13. Sealing groove; 14. Oil passage; 15. Gas passage; 16. Step hole; 17. Volume increasing groove; 18. Mounting seat; 19. Tray; 10. Guide rod;

[0032] 2. Airbag; 2A. Pneumatic cabin; 21. Sealing ring; 22. Compensation chamber; 23. Air storage space;

[0033] 3. Liquid bag; 3A. Hydraulic cabin; 31. Open end; 32. Sealing flange;

[0034] 4. Hydraulic control unit; 41. Hydraulic pump; 42. First one-way valve; 43. First solenoid valve; 44. Oil pipeline; 45. Oil return pipeline;

[0035] 5. Pneumatic control unit; 51. Air pump; 52. Second one-way valve; 53. Second solenoid valve; 54. Inflation pipeline; 55. Exhaust pipeline;

[0036] 6. Fuel tank;

[0037] 7. Fairing; 71. Connecting port; 72. Fixed flange;

[0038] 8. Cable tension sensor. Detailed implementation manners

[0039] Next, the technical solutions in the embodiments will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0040] In the description of the present invention, it should be understood that the terms "center", "transverse", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0041] The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third" may explicitly or implicitly include one or more of such features.

[0042] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0043] As Figures 1 to 4 shown, in a schematic embodiment of the buoyancy adjustment device for an underwater vehicle of the present invention, the buoyancy adjustment device for an underwater vehicle includes a pressure-resistant cabin body 1, an assembly part 11 is arranged on the outer side of the pressure-resistant cabin body 1, and an airbag 2 and a liquid bag 3 are installed on the assembly part 11 so that the two are on the outer side.

[0044] A hydraulic control unit 4, a pneumatic control unit 5 and a fuel tank 6 are installed inside the pressure-resistant cabin 1. The hydraulic control unit 4 is respectively connected to the liquid bag 3 and the fuel tank 6 to enable the oil to flow between the liquid bag 3 and the fuel tank 6. The pneumatic control unit 5 is respectively connected to the air bag 2 and the pressure-resistant cabin 1 to enable the gas to flow between the air bag 2 and the pressure-resistant cabin 1.

[0045] The outer periphery of the liquid bag 3 and the outer periphery of the air bag 2 are both fixed on the assembly part 11. The outer periphery of the liquid bag 3 is located outside the air bag 2, so that the liquid bag 3 wraps the air bag 2, thereby forming a pneumatic cabin 2A between the air bag 2 and the assembly part 11 and a hydraulic cabin 3A between the air bag 2 outside the assembly part 11 and the liquid bag 3.

[0046] When the underwater vehicle is in a low-pressure underwater environment, the pneumatic control unit 5 sends the gas in the internal space of the pressure-resistant cabin 1 into the air bag 2, causing the air bag 2 to expand. The expanded air bag 2 directly contacts the liquid bag 3 and pushes it outward, or indirectly pushes it outward through the oil in the liquid bag 3, thereby causing the liquid bag 3 to expand, increasing the volume of the displaced liquid, and thus increasing the buoyancy. The pneumatic control unit 5 sends the gas filled in the air bag 2 back into the pressure-resistant cabin 1. The air bag 2 shrinks and stops pushing the liquid bag 3 outward. The liquid bag 3 shrinks under the action of the underwater liquid pressure and its internal negative pressure, and the volume of the displaced liquid decreases, thereby reducing the buoyancy. When the underwater vehicle is in a high-pressure underwater environment, the hydraulic control unit 4 sends the oil in the fuel tank 6 into the liquid bag 3, causing the liquid bag 3 to expand, increasing the volume of the displaced liquid, and increasing the buoyancy. The hydraulic control unit 5 sends the oil filled in the liquid bag 3 back into the fuel tank 6. The liquid bag 3 shrinks, and the volume of the displaced liquid decreases, thereby reducing the buoyancy.

[0047] The air bag 2 is wrapped in the liquid bag 3, enabling the air bag 2 and the liquid bag 3 to share the installation space, making the structure of the buoyancy adjustment device more compact, and realizing multi-functional buoyancy adjustment and energy consumption reduction without increasing the installation space. With the air bag 2 inside and the liquid bag 3 outside, the liquid in the liquid bag 3 maintains a stable volume under the action of the underwater liquid pressure and can directly transmit the underwater liquid pressure inward to the air bag 2. The power transmission process has minimal loss, enabling the air bag 2 to be emptied relatively quickly under the indirect action of the underwater liquid pressure, increasing the speed of buoyancy reduction, and ensuring that the buoyancy can be adjusted to the lowest level.

[0048] In the above-described exemplary embodiments, the buoyancy adjustment device for the underwater vehicle has two buoyancy-changing structures, namely an airbag and a liquid bag. The two buoyancy adjustment structures can work together to diversify the working modes of buoyancy adjustment. In a low-pressure underwater environment, the gas will not be significantly compressed under a large pressure, and at this time, by inflating and deflating the airbag, the volume of the airbag can be effectively changed to adjust the buoyancy. Moreover, the gas has stronger fluidity than the liquid, and the buoyancy adjustment is faster. In a high-pressure underwater environment, the liquid can withstand a large pressure and maintain the relative stability of its own volume. At this time, by filling and discharging the liquid bag with liquid, the volume of the liquid bag can be effectively changed to adjust the buoyancy, and the influence of the external pressure on the buoyancy adjustment is smaller. The buoyancy adjustment device can adapt to high-pressure and low-pressure external environments, and the buoyancy can be increased or decreased, with less working limitations. Compared with the buoyancy adjustment method of sucking and discharging seawater to change the self-weight, the energy consumption is less. Moreover, in a low-pressure environment, the gas can be filled into the airbag without a large force, and the load of the air pressure control unit is small, and the energy consumption can be further reduced. In addition, the pressure in the underwater environment can act on the liquid bag to indirectly and directly send the filled gas and liquid back to the pressure-resistant cabin and the fuel tank, reducing the active action of the air pressure control unit and the hydraulic control unit on the gas and liquid, and reducing the energy consumption. The airbag is nested in the liquid bag, sharing the installation space, and the device structure is more compact, solving the problems of the current buoyancy adjustment device with a single form, large energy consumption, and strong limitations.

[0049] In order to further reduce the energy consumption and make it easier for the gas and liquid to be discharged from the airbag 2 and the liquid bag 3, the internal space of the pressure-resistant cabin 1 is always in a negative pressure state. The gas filled in the airbag 2 is sucked back into the internal space of the pressure-resistant cabin 1 under the action of the negative pressure, and the liquid filled in the liquid bag 3 flows back into the fuel tank 6 in the pressure-resistant cabin 3 under the action of the negative pressure and the external underwater liquid pressure. The air pressure control unit 5 and the hydraulic control unit 4 do not need to actively act on the gas and liquid, thereby reducing the energy consumption. When the air pressure control unit 5 fills the air in the pressure-resistant cabin 1 into the airbag 2, the air in the pressure-resistant cabin 1 decreases and a negative pressure is generated, which can also achieve the same effect of reducing the energy consumption of the air flowing back.

[0050] In some embodiments, the airbag 2 extends into its interior through an opening 31 formed on the outer periphery of the liquid bag 3, that is, the liquid bag 3 sleevs the airbag 2 through the opening 31. The sealing flange 32 provided around the opening 31 is pressed and fixed on the assembly part 11 by a circular fixing member to achieve the sealed connection between the liquid bag 2 and the assembly part 11.

[0051] In some embodiments, a fairing 7 is installed on the assembly part 11. The fairing 7 sleeves the liquid bladder 3, so that the liquid bladder 3 and the airbag 2 inside it are both located within the fairing 7. The fairing 7 makes the overall shape of the underwater vehicle streamlined, allowing water to flow smoothly over it and reducing the navigation resistance. To ensure that the expandable and contractible liquid bladder 3 can change the volume of the displaced liquid and thus change the buoyancy, the fairing 7 has a communication port 71 through which liquid can enter.

[0052] The fixing part is a fixing flange 72 provided for the fairing 7. The fixing flange 72 is installed on the assembly part 11, pressing and fixing the sealing flange 32 on the assembly part 11, realizing the sealing of the liquid bladder 3 by the assembly part 11. The fairing 7 not only conducts the flow of water but also plays a fixing role, reducing the number of device components and the overall weight of the underwater vehicle, making the underwater vehicle more flexible in floating and diving.

[0053] The assembly part 11 is provided with a stepped hole 16. The airbag 2 is installed on the step of the stepped hole 16. The open end 31 of the liquid bladder 3 is pressed by the fixing part around the outside of the stepped hole 16. The liquid bladder 3 covers the stepped hole 16, causing the airbag 2 and the liquid bladder 3 to be axially offset to a certain extent. When the liquid bladder 3 contracts, it can sink into the stepped hole 16, and the buoyancy can be adjusted to a lower level, making the underwater vehicle dive faster.

[0054] In some embodiments, the fairing 7 is cylindrical, and the communication port 71 is the port at the outer end of the fairing, having a relatively large inner diameter. Underwater liquid can flow in and out of the fairing 7 quickly and fully contact the liquid bladder 3, efficiently changing the volume of the displaced liquid and flexibly adjusting the buoyancy.

[0055] In some embodiments, the assembly part 11 presses and fixes the outer periphery of the airbag 2 on the assembly part 11 through a clamping ring 12 installed, thereby closing the airbag 2 to form a pressure cabin 2A. The outer periphery of the airbag 2 has a sealing ring 21. The sealing ring 21 is pressed and fixed in a sealing groove 13 opened on the assembly part 11 through the clamping ring 12, thereby increasing the airtightness of the airbag 2.

[0056] In some embodiments, a volume increasing groove 17 is opened on the end face of the assembly part 11. The airbag 2 forms an air storage space 23 by indenting outward. Both the volume increasing groove 17 and the air storage space 23 increase the volume of the pressure cabin, raising the upper limit of the adjustable buoyancy. The volume increasing groove 17 and the air storage space 23 are symmetrically arranged, with the same shape and opposite directions. The inner wall of the airbag 2 can completely adhere to the surface of the volume increasing groove 17 without generating wrinkles, so that all the gas in the airbag 2 is emptied in this state, ensuring that the buoyancy can be adjusted to the lowest level.

[0057] In some embodiments, such as Figures 2 to 4As shown in the figure, the hydraulic control unit 4 includes a hydraulic pump 41, a first check valve 42, and a first solenoid valve 43. The assembly part 11 is provided with an oil passage 14 communicating with the liquid bladder 3. The fuel tank 6 is respectively communicated with the oil passage 14 through an oil delivery pipeline 44 and an oil return pipeline 45. The hydraulic pump 41 and the first check valve 42 are installed on the oil delivery pipeline 44, and the first solenoid valve 43 is installed on the oil return pipeline 45. The oil delivery pipeline 44, the oil return pipeline 45, and the oil passage 14 can be connected through a tee.

[0058] When the first solenoid valve 43 closes the oil return pipeline 45, the hydraulic pump 41 pumps the oil in the fuel tank 6 and sends it into the liquid bladder 3 through the oil delivery pipeline 44. The liquid bladder 3 expands, increasing the buoyancy. The first check valve 42 uses its one-way passing function to prevent the oil from flowing back through the oil delivery pipeline 44. At the same time, by using the first solenoid valve 43 to close the oil return pipeline 45, the expanded state of the liquid bladder 3 is maintained when the hydraulic pump 41 stops running, saving energy consumption. When the first solenoid valve 43 opens the oil return pipeline 45, under the action of the expanded liquid bladder 3 and the underwater liquid pressure, the oil filled in the liquid bladder 3 returns to the fuel tank 6 through the oil return pipeline 45. The liquid bladder 3 shrinks, and the buoyancy decreases. Without additional power, the energy consumption is small.

[0059] In some embodiments, as Figures 2 to 4 shown in the figure, the pneumatic control unit 5 includes an air pump 51, a second check valve 52, and a second solenoid valve 53. The assembly part 11 is provided with a gas passage 15 communicating with the airbag 2. The pressure-resistant cabin 1 is respectively communicated with the gas passage 15 through an air filling pipeline 54 and an exhaust pipeline 55. The air pump 51 and the second check valve 52 are installed on the air filling pipeline 54, and the second solenoid valve 53 is installed on the exhaust pipeline 55. The air filling pipeline 54, the exhaust pipeline 55, and the gas passage 15 can be connected through a tee.

[0060] When the first solenoid valve 53 closes the exhaust pipeline 55, the air pump 51 pumps the gas in the internal space of the pressure-resistant cabin 1 and sends it into the airbag 2 through the air filling pipeline 54. The airbag 2 expands, increasing the buoyancy. The second check valve 52 uses its one-way passing function to prevent the gas from flowing back through the air filling pipeline 54. At the same time, by using the second solenoid valve 53 to close the exhaust pipeline 55, the expanded state of the airbag 2 is maintained when the air pump 51 stops running, saving energy consumption. When the second solenoid valve 53 opens the exhaust pipeline 55, under the action of the expanded airbag 2 and the underwater liquid pressure, the gas filled in the airbag 2 returns to the internal space of the pressure-resistant cabin 1 through the exhaust pipeline 55. The airbag shrinks, and the buoyancy decreases. Without additional power, the energy consumption is small.

[0061] When the airbag 2 is covered in the liquid bladder 3, the liquid bladder 3 contacts the underwater liquid. The underwater liquid pressure acts on the airbag 2 through the liquid bladder 3 and the oil in it, so as to discharge the gas in the airbag 2 when the second solenoid valve 53 is opened.

[0062] In some embodiments, the airbag 2 is provided with a closed compensation chamber 22 filled with gas, which keeps the compensation chamber 22 in a full state. When the underwater vehicle dives to a certain depth, as the diving depth increases, the pressure of the underwater liquid increases and acts on the compensation chamber 22 directly or indirectly, causing the gas in the compensation chamber 22 to be compressed under the pressure, reducing the volume of the compensation chamber 22, achieving the effect of reducing buoyancy, and thus enabling the underwater vehicle to dive faster. At the same time, as the diving depth increases, the ambient temperature decreases, and the volume of the gas in the compensation chamber 22 will also be compressed due to thermal expansion and contraction, achieving the effect of further reducing buoyancy. When the underwater vehicle floats, as the pressure of the underwater liquid decreases and the temperature rises, the compensation chamber 22 can gradually expand, increasing buoyancy and accelerating the floating speed.

[0063] In some embodiments, the fuel tank 6 is a corrugated pipe with both ends closed, enabling the fuel tank 6 to axially expand and contract. When the hydraulic control unit 4 pumps out the oil in it, the fuel tank 6 can shorten under the action of negative pressure, avoiding excessive negative pressure in the fuel tank and preventing the load of the hydraulic control unit 4 from increasing when pumping out the oil. When the oil flows back into the fuel tank 6, the fuel tank 6 can elongate. By the elongation and shortening of the fuel tank 6, the change in the volume of the fuel tank 6 can be obtained, and then the capacity of the oil in the fuel tank 6 can be monitored.

[0064] To ensure the axial contraction of the fuel tank 6, a mounting seat 18 is fixedly installed in the pressure-resistant cabin 1. One end of the fuel tank 6 is installed on the mounting seat 18, and the other end is installed with a tray 19. A plurality of axially arranged guide rods 10 are installed on the mounting seat 18, and the guide rods 10 all pass through the corresponding guide holes of the tray 19. Through the guidance of the guide rods 10, the tray 19 moves axially, thereby realizing the axial contraction of the fuel tank 6 and making the change in the fuel tank volume proportional to the change in its length. To measure the change in the length of the fuel tank 6, a wire-pulling sensor 8 is installed on the mounting seat. The measuring wire of the wire-pulling sensor 8 is connected to the tray 19 or the inner end of the fuel tank 6. When the length of the fuel tank 6 changes, the length of the measuring wire pulled out will also change accordingly, and then the change in the fuel tank length can be obtained.

[0065] Finally, it should be noted that the embodiments in this specification are described in a progressive manner, and the key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the specific implementation manners of the present invention can still be modified or some technical features can be equivalently replaced without departing from the spirit of the technical solutions of the present invention, and they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A buoyancy adjustment device for an underwater vehicle, characterized in that, it includes a pressure-resistant cabin body, an assembly part is arranged on the outer side of the pressure-resistant cabin body, and an airbag and a liquid bag are installed on the assembly part; a hydraulic control unit, a pneumatic control unit and a fuel tank are installed in the pressure-resistant cabin body; the hydraulic control unit is respectively communicated with the liquid bag and the fuel tank to enable the oil to flow between the liquid bag and the fuel tank; the pneumatic control unit is respectively communicated with the airbag and the pressure-resistant cabin body to enable the gas to flow between the airbag and the pressure-resistant cabin body; the outer periphery of the liquid bag and the outer periphery of the airbag are both fixed on the assembly part, and the liquid bag covers the airbag, thereby forming a pneumatic cabin located between the airbag and the assembly part and a hydraulic cabin located between the airbag and the liquid bag.

2. The buoyancy adjustment device for an underwater vehicle according to claim 1, characterized in that, the airbag extends into its interior through an opening provided on the outer periphery of the liquid bag, and the sealing flange provided with the opening in a ring shape is pressed and fixed on the assembly part through an annular fixing member.

3. The buoyancy adjustment device for an underwater vehicle according to claim 2, characterized in that, a fairing is installed on the assembly part, the fairing has a communication port that can allow liquid to enter and exit, and the liquid bag is sleeved; the fixing member is a fixing flange provided on the fairing, and the fixing flange is installed on the assembly part and presses the sealing flange.

4. The buoyancy adjustment device for an underwater vehicle according to claim 3, characterized in that, the fairing is in a cylindrical shape, and the communication port is the port at the outer end of the fairing.

5. The buoyancy adjustment device for an underwater vehicle according to claim 1, characterized in that, the assembly part presses and fixes the outer periphery of the airbag on the assembly part through a tightening ring installed, the outer periphery of the airbag has a sealing ring, and the sealing ring is pressed and fixed in a sealing groove provided on the assembly part through the tightening ring.

6. The buoyancy adjustment device for an underwater vehicle according to claim 1, characterized in that, a volume increasing groove is provided on the end face of the assembly part, the airbag forms an air storage space by recessing outward, and the volume increasing groove and the air storage space are symmetrically arranged, so that when the pneumatic cabin is emptied, the airbag adheres to the inner wall of the volume increasing groove.

7. The buoyancy adjustment device for an underwater vehicle according to claim 1, characterized in that, the hydraulic control unit includes a hydraulic pump, a first one-way valve and a first solenoid valve; the assembly part is provided with an oil passage communicated with the liquid bag, and the fuel tank is respectively communicated with the oil passage through an oil delivery pipeline and an oil return pipeline; the hydraulic pump and the first one-way valve are installed on the oil delivery pipeline, and the first solenoid valve is installed on the oil return pipeline.

8. The buoyancy adjustment device for an underwater vehicle according to claim 1, characterized in that, the pneumatic control unit includes an air pump, a second one-way valve and a second solenoid valve; the assembly part is provided with a gas passage communicated with the airbag, and the pressure-resistant cabin body is communicated with the gas passage through an air filling pipeline and an exhaust pipeline; The air pump and the second one-way valve are installed on the charging pipeline, and the second electromagnetic valve is installed on the exhaust pipeline.

9. The buoyancy adjustment device for an underwater vehicle according to claim 1, wherein, the airbag is provided with a closed compensation cavity filled with gas.

10. The buoyancy adjustment device for an underwater vehicle according to claim 1, wherein, the fuel tank is a corrugated pipe with both ends closed.

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