Pressure control device between bottom-shared storage tanks and use method

Abstract

The invention provides a pressure control device between bottom-shared storage tanks and a using method. Pressurized gas in the high-pressure gas cylinder is adjusted to rated working pressure through the pressure reducing valve and then enters the storage box through the first gas port, the gas in the storage box enters the pressure sensing cavity of the difference control device through the second gas port of the storage box, and the gas inlet opening degree is controlled through the pressure difference in the pressure sensing cavity, so that the gas inlet rate and the pressure difference in the common-bottom storage box are controlled, and the gas inlet efficiency is improved. The exhaust principle is similar to the air inlet principle. The method is high in control precision and rapid in response, external pressure transmission is not needed, and pressure difference control in the common-bottom storage tank in the pressurization and deflation process can be achieved in a self-adaptive mode through an electric control valve and a control program.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressurized delivery of aircraft propulsion systems, and in particular, relates to a method for controlling the pressure between tanks during pressurization and depressurization of a common bottom tank. Background Art

[0002] The common bottom tank can enable the two-component system to effectively save the structural space of the aircraft, but the pressure-bearing capacity of the shared bottom in the middle is weak. If the common bottom is strengthened and thickened, the structural mass will increase sharply.

[0003] In the past, common bottom tanks were often used in rocket tanks. For example, Chinese patent document "Common Bottom Tank Propulsion System for Spacecraft" with publication number CN116280277A provides a common bottom tank propulsion system for spacecraft, including a parallel cross-air path system, a cross-supply liquid path system, a double-layer common bottom tank and its pressure replenishment and pressure relief system and a remaining amount measurement system; the parallel cross-air path system is used to realize air path cross-supply to the double-layer common bottom tank; the double-layer common bottom tank cross-supplies liquid path propellant to the engine through the cross-supply liquid path system; the pressure replenishment and pressure relief system is used to adjust the common bottom pressure difference and absolute pressure of the double-layer common bottom tank; the remaining amount measurement system is used to measure the remaining amount of propellant in orbit.

[0004] However, the rocket tank pressure is relatively low, only within 0.6MPa, while the rated working pressure of the space vehicle often reaches more than 2MPa. When the pressure difference between the two cavities is large, the diaphragm between the propellants will rupture, causing the oxygen-fuel propellant to mix, leading to catastrophic risks.

[0005] The Chinese patent document "Common bottom tank propulsion system for spacecraft" with publication number CN116280277A and the Chinese patent document "Pressure delivery system, liquid launch vehicle and control method of pressure delivery system" with publication number CN117569948A, both of which use the pressure difference control of the common bottom tank to monitor the pressure in each of the two cavities to determine the pressure difference, use program control software to open and close the electromagnetic valve to replenish air for control. This solution requires the addition of multiple electromagnetic valves, relies on external power supply, sensor accuracy, feedback control program, and even requires the addition of an additional system. At the same time, it stipulates that the pressure in one cavity must be greater than that in another cavity, and many other conditions, and the control means and logic are relatively complex. Summary of the invention

[0006] In view of the defects in the prior art, an object of the present invention is to provide a pressure control device between common-bottom storage tanks and a method for using the same.

[0007] A pressure control device for a common bottom storage tank provided by the present invention comprises: a high pressure gas cylinder 1, a high pressure self-locking valve 2, a pressure reducing valve 3, a one-way valve 4, and an intake pressure difference control device 5;

[0008] High-pressure gas is stored in a high-pressure gas cylinder 1, and is reduced in pressure to a set pressure value by a pressure reducing valve 3 after being output through a high-pressure self-locking valve 2. The high-pressure gas then passes through a one-way valve 4 for oxygen and fuel and enters an intake pressure difference control device 5 to adjust the intake rate of the pressurized gas. The pressurized gas enters an oxygen tank 11 and a fuel tank 12 having a common bottom tank 10, respectively, until the pressure of the oxygen tank 11 and the fuel tank 12 reaches the pressure setting value of the pressure reducing valve, thereby completing the pressurization of the tanks.

[0009] Preferably, it also includes: a first air port 6 and a second air port 7;

[0010] The intake pressure difference control device 5 comprises: a pressure sensing chamber 51, an intake chamber 52, a pressure sensing membrane box 53, an intake valve core 54, an intake valve seat 55, and a dynamic seal 56;

[0011] The air cavities of the oxygen tank 11 and the fuel tank 12 are both provided with two air ports, namely a first air port 6 and a second air port 7;

[0012] The first gas port 6 realizes the gas charging and discharging port of the oxygen fuel storage tank;

[0013] The second air hole 7 is connected to the pressure-sensing chamber 51 of the air intake pressure difference control device 5 and the air outlet pressure difference control device 8, and the real-time pressure value in the oxygen-fuel storage tank is fed back to the respective pressure-sensing membrane boxes 53. The pressure-sensing membrane box 53 is rigidly connected to the air intake valve core 54, and the oxygen and fuel air intake valve cores 54 are also rigidly connected; the air intake valve core 54 and the pressure-sensing chamber 51 and the air intake chamber 52 are isolated from the outside world through the dynamic seal 56 to maintain the sealing state of the cavity.

[0014] Preferably, when the tank is taking in air, if the pressure of the oxygen tank is too high, the pressure-sensitive diaphragm box 53 on the oxygen side will be compressed, and the pressure-sensitive diaphragm box 53 on the fuel side will relax, which will drive the intake valve core 54 to move toward the oxygen side of the intake pressure difference control device 5. Due to the matching structure of the intake valve core 54 and the intake valve seat 55, the boost channel gradually decreases, and the intake channel on the fuel side gradually increases.

[0015] Preferably, if the pressure difference between the oxygen tank 11 and the fuel tank 12 sensed in the oxygen-side and fuel-side pressure-sensing chambers 51 exceeds a set threshold, the pressure-sensitive membrane box 53 is compressed and relaxed to completely close the intake valve core 54 and the intake valve seat 55 on the side with high pressure, thereby locking the intake and achieving the maximum opening on the other side with low pressure.

[0016] Preferably, it also includes: an outlet pressure difference control device 8;

[0017] When releasing air and relieving pressure, the exhaust pressure difference control device 8 is used to control the exhaust speed on both sides of the oxygen and fuel to maintain the pressure difference between the oxygen and fuel tanks on both sides; during the pressure relief process, the high-pressure self-locking valve 2 is closed, and the exhaust valves 9 on the oxygen side and the fuel side are opened; when the pressure on one side is higher, the exhaust pressure difference control device 8 will increase the opening on the corresponding side, and reduce the opening on the other side with lower pressure, reduce the exhaust speed, or close the device without exhausting, until the pressure on both sides of the oxygen and fuel is maintained within the set diaphragm safety pressure difference range.

[0018] Preferably, the air pressure in the pressure-sensing chamber 51 will cause the pressure-sensing membrane box 53 to deform, thereby driving the valve core in the device to produce lateral displacement. The valve cores and valve stems of the two air intake pressure difference control devices 5 for oxygen and gas are connected. The pressure difference in the pressure-sensing chamber 51 is used to control the movement direction of the valve core and the air intake opening, thereby controlling the air intake rate and the pressure difference in the common bottom tank.

[0019] Preferably, if the pressure difference reaches the set red line, the valve core and the base of the air inlet chamber on the side with higher pressure are closed, thereby locking the air intake of the chamber. When the pressure on the other side rises to within the allowable pressure difference range, the ventilation channel is gradually opened to continuously maintain the pressure between the two chambers.

[0020] Preferably, the pressure sensing chamber 51, the air inlet chamber 52, the pressure sensing membrane box 53 and the air inlet valve core 54 are on the same axis;

[0021] The pressure sensing chamber 51 and the air inlet chamber 52 are fixed to the position of the system product and cannot move. The air inlet valve core 54 is connected to the pressure sensing chamber 51 and the air inlet chamber 52 in a dynamic sealing manner.

[0022] The pressure-sensitive membrane box 53 is in a pre-compressed state when installed and can be compressed and extended;

[0023] The inner cavity of the pressure-sensitive membrane box 53 is connected to the atmosphere, and the outer portion thereof is exposed to the pressure-sensitive cavity 51, and is elastically deformed by the pressure in the pressure-sensitive cavity.

[0024] The intake valve core 54 includes: a live connection tail, a pressure sensing portion and a sealing head cone;

[0025] The movable connection tail enables the valve core to be relatively connected, and the pressure sensing part is subjected to the gas pressure in the tank in the pressure sensing cavity 51, thereby pressing the pressure sensing membrane box 53 to elastically deform;

[0026] The intake valve seat 55 and the head cone of the intake valve core 54 have different flow cross-sectional areas under different strokes;

[0027] The closer the head cone of the intake valve core 54 is to the intake valve seat 55, the smaller the flow cross-sectional area becomes, until they fit perfectly together, and the air path can be completely closed and circulated;

[0028] The deformation direction of the pressure-sensitive membrane box 53 is opposite to the direction in which the flow area of ​​the intake pressure difference control device 5 increases and decreases.

[0029] According to a method for using the common bottom tank pressure control device provided by the present invention, the following steps are included:

[0030] Step 1: The pressurized gas in the high-pressure gas cylinder 1 is adjusted to the rated working pressure through the pressure reducing valve 3;

[0031] Step 2: The gas enters the storage tank through the first gas port 6;

[0032] Step 3: The gas in the tank will enter the pressure sensing cavity of the intake pressure difference control device 5 through the second gas port 7 of the tank;

[0033] Step 4: The air pressure will cause the pressure-sensitive membrane box 53 to deform, thereby driving the air inlet valve core 54 in the device to produce lateral displacement;

[0034] Step 5: The intake valve core 54 and the valve stem at both ends of the intake pressure difference control device 5 are connected, and the moving direction of the intake valve core 54 is controlled by the pressure difference in the pressure sensing chamber 51, and the intake opening is controlled, so as to control the intake rate and the pressure difference in the common bottom tank.

[0035] Preferably, the method further comprises the following steps:

[0036] Step 6: When the working pressure of the oxygen-fuel tank is inconsistent or the gas volume caused by the oxygen-fuel mixing ratio is inconsistent, adapt to it by changing the pre-compression force of the pressure-sensitive membrane box 53, the intake valve seat 55, the vent size of the exhaust valve 9 and the relative size of the intake valve core 54 head cone.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The present invention does not require external sensors, power supplies, and control host to perform logical judgment and then send the control model to the valve to perform logical adjustment to balance the opening and closing of the valve.

[0039] 2. The present invention can quickly and real-time balance the pressure in the oxygen combustion chamber during the process of pressurization and depressurization of the common bottom tank.

[0040] 3. For space vehicles, system complexity and weight need to be given priority consideration. The present invention only requires adding an intake pressure difference control device and an exhaust pressure difference control device to the air path delivery system of the original propulsion system, and the device can be designed and manufactured to be smaller in size without the need to add a set of complex additional systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0042] Figure 1 It is a schematic diagram of the overall structure of the pressure control device between common bottom tanks;

[0043] Figure 2 It is a schematic diagram of the structure of the intake pressure difference control device;

[0044] Figure 3 It is a schematic diagram of the exhaust pressure difference control device structure.

[0045] The figure shows:

[0046] DETAILED DESCRIPTION

[0047] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0048] The working principle of the present invention is:

[0049] The oxygen tank 11 and the fuel tank 12 of the common bottom tank 10 share a common bottom. Generally speaking, the common bottom tank 10 can reduce the requirements of space layout, the overall mass, the thermal control requirements between the oxygen and fuel tanks, etc. However, since the bottom structure between the oxygen tank 11 and the fuel tank 12 is flat, its pressure resistance is relatively weak. If the common bottom tank 10 as the middle bottom is damaged, it will cause devastating damage to the entire spacecraft. Therefore, it is necessary to control the pressure difference between the two chambers of the oxygen tank 11 and the fuel tank 12 during the pressurization and depressurization of the common bottom tank 10.

[0050] In actual applications, the initial liquid levels and air cavity sizes in the oxygen tank 11 and the fuel tank 12 are not exactly the same, and the volume flow requirements of the pressurized / exhaust gas in the oxygen tank 11 and the fuel tank 12 during engine operation and at the end of system operation are not completely consistent, which increases the difficulty of pressure control between the oxygen tank 11 and the fuel tank 12, that is, between the oxygen and fuel tanks.

[0051] The high-pressure gas of the space propulsion system is stored in the high-pressure gas cylinder 1. When the high-pressure self-locking valve 2 is opened, the system starts to pressurize. The high-pressure gas in the high-pressure gas cylinder 1 is output and reduced to a set pressure value by the pressure reducing valve 3. Then, it passes through the one-way valves 4 for oxygen and fuel respectively and enters the intake pressure difference control device 5 to adjust the intake rate. Finally, the pressurized gas enters the oxygen tank 11 and the fuel tank 12 of the common bottom tank 10 respectively, until the pressure of the oxygen tank 11 and the fuel tank 12 are fully increased to the pressure setting value of the pressure reducing valve, thereby completing the pressurization of the tanks.

[0052] The present invention provides two air ports, a first air port 6 and a second air port 7, in the air cavities of the oxygen tank 11 and the fuel tank 12. The first air port 6 is used for charging and discharging the oxygen-fuel tank, and the second air port 7 is connected to the pressure-sensing cavity 51 of the air inlet pressure difference control device 5 and the air outlet pressure difference control device 8, and the real-time pressure value in the oxygen-fuel tank is fed back to the respective pressure-sensing membrane box 53. The pressure-sensing membrane box 53 is fixedly connected to the air inlet valve core 54, and the air inlet valve core 54 of oxygen and fuel is also rigidly fixedly connected. The air inlet valve core 54 and the pressure-sensing cavity 51 and the air inlet cavity 52 are isolated from the outside by maintaining the sealed state of the cavity through the dynamic seal 56. When the tanks are inhaled, if the pressure of the oxygen tank is too high, the pressure-sensitive membrane box 53 on the oxygen side will be compressed, and the pressure-sensitive membrane box 53 on the fuel side will be relaxed, which will drive the intake valve core 54 to move toward the oxygen side of the intake pressure difference control device 5. Due to the special matching structure of the intake valve core 54 and the intake valve seat 55, the boost passage will gradually decrease to reduce the intake amount, while the intake passage on the fuel side will gradually increase to increase the intake amount and control the pressure difference. If the pressure difference between the oxygen tank 11 and the fuel tank 12 sensed in the oxygen / fuel pressure-sensitive cavity 51 is too large, the intake valve core 54 and the intake valve seat 55 on the side with high pressure will be completely closed through the compression and relaxation of the pressure-sensitive membrane box 53 to achieve locked intake, and the opening of the other side with low pressure will reach the maximum, and air will be quickly inhaled, thereby gradually balancing the pressure in the tanks on both sides. Thus, the pressure balance of the oxygen and fuel tanks in the process of controlling the boosting of the common bottom tank 10 is achieved.

[0053] When the propulsion system finishes working and is passivated, the system will be vented and depressurized. During depressurization, the oxygen / fuel tank depressurization speed will be different, just like the supercharging. The exhaust pressure difference control device 8 needs to be used to control the deflating speed on both sides to maintain the pressure difference between the oxygen / fuel tanks on both sides. During the depressurization process, the high-pressure self-locking valve 2 is closed, and the oxygen / fuel deflating valve 9 is opened. The exhaust pressure difference control device 8 has a similar working structure principle to the intake pressure difference control device 5. The difference is that the exhaust valve core 82 and the exhaust valve seat 83 in the exhaust chamber 81 are in the opposite matching structure to the intake valve core 54 and the intake valve seat 55. When the pressure on one side is high, the corresponding side of the exhaust pressure difference control device 8 will increase the opening, thereby increasing the exhaust volume and quickly reducing the pressure on that side. If the pressure on the other side is low, the opening will be reduced, the exhaust speed will be reduced, and even closed without exhausting, until the pressure on both sides is maintained within the set diaphragm safety pressure difference range.

[0054] The present invention is described in more detail below.

[0055] A liquid oxygen-methane system using a common bottom tank has a rated working pressure of 2.5 MPa for the oxygen tank and a rated working pressure of 2.3 MPa for the fuel tank. Two pressure reducing valves 3 are used. The pressurized gas in the high-pressure gas cylinder 1 is adjusted to the rated working pressure in the respective chambers through the respective pressure reducing valves 3, and the gas enters the oxygen tank 11 and the fuel tank 12 respectively through the first gas port 6.

[0056] The gas in the tank will enter the pressure sensing chamber 51 of the intake pressure difference control device 5 through the second gas port 7 of the tank.

[0057] Due to the setting of the mixing ratio, the oxygen consumed when the engine is working is consistent with the gas flow required by the methane fuel gas. Therefore, the vent sizes of the intake valve seat 55 and the outlet valve seat, the valve core, the pressure sensing chamber 51, the intake chamber, the outlet chamber, the installation spacing, etc. are all the same. Since the rated working pressure of the oxygen storage tank 11 is 0.2 MPa higher than the working pressure of the fuel storage tank 12, when the pressure sensing membrane box 53 is pre-compressed, the oxygen path pressure sensing membrane box is pre-compressed by 0.2 MPa more than the methane pressure sensing membrane box.

[0058] The air pressure in the pressure-sensing chamber 51 will cause the pressure-sensing membrane box 53 to deform, thereby driving the valve core in the device to produce lateral displacement. The valve core and valve stem of the oxygen and gas intake pressure difference control devices 5 are connected. The pressure difference in the pressure-sensing chamber 51 is used to control the movement direction of the valve core and the intake opening, thereby controlling the intake rate and the pressure difference in the common bottom tank. If the pressure difference reaches the set red line, the valve core will close with the base of the intake chamber on the side with higher pressure, thereby locking the intake of the chamber. When the pressure on the other side rises to within the allowable pressure difference range, the ventilation channel will gradually open to continuously maintain the pressure between the two chambers. The exhaust principle is similar to the intake principle.

[0059] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0060] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A pressure control device for a common bottom storage tank, characterized in that: include: High-pressure gas cylinder (1), high-pressure self-locking valve (2), pressure reducing valve (3), one-way valve (4), and intake pressure difference control device (5); High-pressure gas is stored in a high-pressure gas cylinder (1), and is output through a high-pressure self-locking valve (2) and then reduced in pressure by a pressure reducing valve (3) to a set pressure value. The high-pressure gas then passes through a one-way valve (4) for oxygen and a one-way valve (4) for fuel and enters an intake pressure difference control device (5) to adjust the intake rate of the pressurized gas. The pressurized gas enters an oxygen tank (11) and a fuel tank (12) having a common bottom tank (10) until the pressure of the oxygen tank (11) and the fuel tank (12) reaches the pressure setting value of the pressure reducing valve, thereby completing the pressurization of the tanks.

2. The pressure control device for common bottom tanks according to claim 1, characterized in that: Also includes: A first gas port (6) and a second gas port (7); The intake pressure difference control device (5) comprises: a pressure sensing chamber (51), an intake chamber (52), a pressure sensing membrane box (53), an intake valve core (54), an intake valve seat (55), and a dynamic seal (56); The air cavities of the oxygen storage tank (11) and the fuel storage tank (12) are both provided with two air ports, namely a first air port (6) and a second air port (7); The first gas port (6) is used to charge and discharge the oxygen fuel tank; The second air hole (7) is connected to the pressure-sensing chamber (51) of the air intake differential pressure control device (5) and the air outlet differential pressure control device (8), and the real-time pressure value in the oxygen-fuel storage tank is fed back to the respective pressure-sensing membrane boxes (53). The pressure-sensing membrane box (53) is fixedly connected to the air intake valve core (54), and the air intake valve cores (54) of oxygen and fuel are also rigidly connected. The air intake valve core (54) and the pressure-sensing chamber (51) and the air intake chamber (52) are sealed and isolated from the outside through the dynamic seal (56).

3. The pressure control device for common bottom tanks according to claim 1, characterized in that: When the tank is taking in air, if the pressure of the oxygen tank is too high, the pressure-sensitive diaphragm box (53) on the oxygen side will be compressed, and the pressure-sensitive diaphragm box (53) on the fuel side will be relaxed, which will drive the intake valve core (54) to move toward the oxygen side of the intake pressure difference control device (5). Due to the matching structure of the intake valve core (54) and the intake valve seat (55), the boost channel is gradually reduced, and the intake channel on the fuel side is gradually increased.

4. The pressure control device for common bottom tanks according to claim 3, characterized in that: If the pressure difference between the oxygen tank (11) and the fuel tank (12) sensed in the oxygen-side and fuel-side pressure-sensing chambers (51) exceeds a set threshold, the pressure-sensing membrane box (53) is compressed and relaxed to completely close the intake valve core (54) and the intake valve seat (55) on the side with higher pressure, thereby locking the intake, and the opening degree on the other side with lower pressure reaches the maximum.

5. The pressure control device for common bottom tanks according to claim 1, characterized in that: Also includes: An outlet pressure difference control device (8); During the air release and pressure relief, the exhaust pressure differential control device (8) is used to control the air release speed on both sides of the oxygen-fuel tank to maintain the pressure difference between the oxygen-fuel tanks on both sides; during the pressure relief process, the high-pressure self-locking valve (2) is closed, and the air release valves (9) on the oxygen side and the fuel side are opened; when the pressure on one side is higher, the exhaust pressure differential control device (8) will increase the opening of the corresponding side, and reduce the opening of the other side with lower pressure, reduce the exhaust speed, or close and do not exhaust, until the pressure on both sides of the oxygen-fuel tank is maintained within the set diaphragm safety pressure differential range.

6. The pressure control device for common bottom tanks according to claim 1, characterized in that: The air pressure in the pressure sensing chamber (51) causes the pressure sensing membrane box (53) to deform, thereby driving the valve core in the device to produce a lateral displacement. The valve cores and valve stems of the oxygen and fuel gas intake pressure difference control devices (5) are connected. The pressure difference in the pressure sensing chamber (51) is used to control the movement direction of the valve core and the intake opening, thereby controlling the intake rate and the pressure difference in the common bottom storage tank.

7. The pressure control device for common bottom tanks according to claim 6, characterized in that: If the pressure difference reaches the set red line, the valve core and the base of the air inlet chamber on the side with higher pressure will close, thereby locking the air intake of the chamber. When the pressure on the other side rises to within the allowable pressure difference range, the ventilation channel will gradually open to continuously maintain the pressure between the two chambers.

8. The pressure control device for common bottom tanks according to claim 2, characterized in that: The pressure-sensing cavity (51), the air intake cavity (52), the pressure-sensing membrane box (53) and the air intake valve core (54) are on the same axis; The pressure sensing chamber (51) and the air intake chamber (52) are fixed to the position of the system product and cannot move, and the air intake valve core (54) is respectively connected to the pressure sensing chamber (51) and the air intake chamber (52) in a dynamic sealing manner; The pressure-sensitive membrane box (53) is in a pre-compressed state when installed and can be compressed and extended; The inner cavity of the pressure-sensitive membrane box (53) is connected to the atmosphere, and the outer portion thereof is exposed to the pressure-sensitive cavity (51), and is elastically deformed by the pressure in the pressure-sensitive cavity; The air intake valve core (54) comprises: a flexible connection tail, a pressure sensing portion and a sealing head cone; The movable connection tail can make the valve core relatively connected, and the pressure sensing part is subjected to the gas pressure in the storage tank in the pressure sensing cavity (51), thereby pressing the pressure sensing membrane box (53) to elastically deform; The intake valve seat (55) and the head cone of the intake valve core (54) have different flow cross-sectional areas under different strokes; The closer the head cone of the intake valve core (54) is to the intake valve seat (55), the smaller the flow cross-sectional area becomes, until they are completely fitted together, and the air path can be completely closed and circulated; The deformation direction of the pressure-sensitive membrane box (53) is opposite to the direction in which the flow area of ​​the intake pressure difference control device (5) increases and decreases.

9. A method for using the pressure control device between common bottom tanks according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: The pressurized gas in the high-pressure gas cylinder (1) is adjusted to the rated working pressure through the pressure reducing valve (3); Step 2: The gases enter the storage tanks through the first gas ports (6); Step 3: The gas in the tank will enter the pressure sensing chamber of the intake pressure difference control device (5) through the second gas port (7) of the tank; Step 4: The air pressure causes the pressure-sensitive membrane box (53) to deform, thereby driving the air inlet valve core (54) in the device to produce lateral displacement; Step 5: The intake valve core (54) and the valve stem at both ends of the intake pressure difference control device (5) are connected, and the moving direction of the intake valve core (54) is controlled by the pressure difference in the pressure sensing chamber (51), thereby controlling the intake opening, thereby achieving the control of the intake rate and the pressure difference in the common bottom tank.

10. The method for using the pressure control device between common bottom tanks according to claim 9, characterized in that: The following steps are also included: Step 6: When the working pressure of the oxygen-fuel tank is inconsistent or the gas volume caused by the oxygen-fuel mixing ratio is inconsistent, the pre-compression force of the pressure-sensitive membrane box (53), the air intake valve seat (55), the air vent size of the air release valve (9) and the relative size of the head cone of the air intake valve core (54) are changed to adapt.

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