Gas safety valve with liquid blocking function under upside-down flight working condition of airplane

Abstract

The utility model provides a gas safety valve with a liquid blocking function under an inverted flight working condition of an airplane. The gas safety valve comprises an upper component and a lower component, the upper assembly comprises a shell, a lining, a sealing disc and a spring. The lower component comprises a sliding sleeve, a base, a first sealing ring and a second sealing ring; the upper component and the lower component are fixedly connected through a bolt, a gasket and a nut; the bushing is arranged in the center of the top of the shell; the end part of the sealing disc guide shaft penetrates through the center of the bushing; a sliding sleeve is arranged in the base. When the aircraft is in an inverted flying condition, the fuel tank can prevent fuel from flowing out of the fuel tank.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft fuel system control, and in particular to a gas safety valve with a liquid-blocking function under an aircraft inverted flight condition. Background Art

[0002] When the fuel pump draws fuel from the tank, the tank level inevitably drops. If the tank is sealed, negative pressure forms inside. This negative pressure not only hinders the pump's ability to draw fuel but can also damage the tank's structure due to the increased pressure differential between the inside and outside. Therefore, fuel tanks are equipped with a ventilation system to introduce compressed air into the tank, maintaining a residual positive pressure. However, excessive positive pressure within the tank can damage the tank structure and increase the amount of fuel entering the engine's combustion chamber, reducing the air ratio and resulting in incomplete combustion and increased fuel consumption. Furthermore, excessive pressure causes more gas to dissolve into the fuel. When the pressure drops, the gas precipitates, causing rapid fuel evaporation and even gas locks.

[0003] Therefore, a safety valve is typically installed in aircraft fuel tanks or vent lines. When the air pressure in the fuel tank exceeds a specified value, the safety valve opens to release pressure, thereby ensuring that the fuel tank's pressurization pressure does not exceed a certain level. However, while existing safety valves can open and release pressure according to a set pressure, in certain operating conditions, such as when an aircraft is flying inverted, the fuel tank will be inverted, and the fuel inside will press against the safety valve's sealing disc. Once the weight of the fuel exceeds the spring thrust, the safety valve will open, and fuel will leak out of the tank through the safety valve, causing damage. Therefore, in the operating condition of an aircraft flying inverted, a safety valve is needed that can release air pressure according to a set pressure value when the aircraft is flying upright, thereby preventing fuel from flowing out of the safety valve when the aircraft is flying inverted. Utility Model Content

[0004] The present application provides a gas safety valve with a liquid-blocking function under an aircraft inverted flight condition, which can be used to solve the technical problem that the safety valve will open when the aircraft is inverted.

[0005] The present application provides a gas safety valve with a liquid-blocking function in an aircraft inverted flight condition, the gas safety valve comprising:

[0006] an upper assembly and a lower assembly;

[0007] The upper assembly includes: housing, bushing, sealing disc, spring;

[0008] The lower component includes: a sliding sleeve, a base, a first sealing ring, and a second sealing ring;

[0009] The upper assembly and the lower assembly are connected and fixed by bolts, washers and nuts; the bushing is set at the center of the top of the shell; the end of the sealing disk guide shaft passes through the center of the bushing;

[0010] The inner part of the base is provided with a sliding sleeve.

[0011] Further, the shell is a cylindrical part with a hollow structure, the bottom is provided with a flange, the flange is perpendicular to the side wall of the shell, and a plurality of shell bolt holes are uniformly distributed on the flange; two circular shell air holes are symmetrically arranged on the side wall of the shell, a machining hole is arranged on the top of the shell, and an inner thread of the shell is arranged in the machining hole.

[0012] Further, the bushing is an equal-thickness cylindrical part, a guide hole is arranged in the inner part, a bushing flange is arranged at the bottom, and an outer thread of the bushing is arranged on the outer side of the side wall of the bushing; the bushing is installed on the top of the shell through the connection of the outer thread of the bushing and the inner thread of the shell.

[0013] Further, the sealing disc is a disc-shaped part, a guide shaft is arranged on one side of the center of the disc, the guide shaft is perpendicular to the disc, and the spring is installed on the outer side of the guide shaft; the sealing disc with the spring is inserted into the guide hole of the bushing.

[0014] Further, the base is a cylindrical part, the inner part is a hollow structure for installing the sliding sleeve, the top is provided with a flange, the flange is perpendicular to the side wall of the base, a plurality of base bolt holes are uniformly distributed on the flange, and the distribution of the base bolt holes corresponds to the shell bolt holes on the flange of the shell; an annular groove region is arranged on the inner side of the flange, which is used for limiting the sliding sleeve.

[0015] Further, the sliding sleeve is a cylindrical part, an annular shoulder is arranged on the top, a sealing inclined groove is arranged on the upper end surface of the annular shoulder, and a sealing straight groove is arranged in the bottom region;

[0016] The first sealing ring is installed in the sealing inclined groove, which is used for sealing between the sealing disc and the sliding sleeve; the first sealing ring is in a stretched state in the sealing inclined groove;

[0017] The second sealing ring is installed in the sealing straight groove, which is used for sliding sealing between the sliding sleeve and the side wall of the base;

[0018] The sliding sleeve is installed in the base from top to bottom and is concentric with the base, the shoulder of the sliding sleeve is arranged in the annular groove on the inner side of the flange of the base, and the gravity of the sliding sleeve can overcome the friction between the second sealing ring and the inner wall of the base and move linearly in the base;

[0019] The second sealing ring is in contact with the sealing straight groove and the inner wall of the base at the same time.

[0020] Further, the flange of the base is butt-jointed with the flange of the shell, the sizes are matched; the shell bolt holes are combined and positioned with the base bolt holes; the bolts, gaskets and nuts connect the upper assembly and the lower assembly into a whole, and the upper assembly and the lower assembly remain coaxial.

[0021] The application is a pure mechanical device, the parts are simple in structure and easy to process, and the manufacturing cost is low. The device is easy to install and is installed on the upper wall plate of the aircraft fuel tank through bolts. In the normal flight condition of the aircraft, the function of the fuel tank gas overpressure safety valve can be realized; when the aircraft is in the inverted flight condition, the fuel can be prevented from leaking from the air vent hole of the application to the outside of the fuel tank. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a three-dimensional schematic view of the device of the application;

[0023] Figure 2 is a cross-sectional view of the application in the non-working state;

[0024] Figure 3 is a cross-sectional view of the application in the normal working state;

[0025] Figure 4 is a cross-sectional view of the application in the inverted flight condition;

[0026] Figure 5 is a cross-sectional view of the sliding sleeve 9 of the application;

[0027] Figure 6 is a cross-sectional view of the bushing 2 of the application.

[0028] In the figure: 1 housing; 2 bushing; 3 sealing disc; 4 spring; 5 bolt; 6 base; 7 first sealing ring; 8 second sealing ring; 9 sliding sleeve; 10 tank top plate; 11 gasket; 12 nut. 21 bushing external thread; 22 housing internal thread; 23 sealing inclined groove; 24 sealing straight groove; 25 housing air vent hole; 26 housing bolt hole; 27 base bolt hole; 28 guide hole; 29 bushing flange. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the application more clear, the embodiments of the application will be further described in detail below with reference to the drawings.

[0030] The application includes upper and lower parts, the upper assembly includes: housing 1, bushing 2, sealing disc 3, spring 4; the lower assembly of the application includes: sliding sleeve 9, base 6, first sealing ring 7, second sealing ring 8; the upper assembly and the lower assembly are connected and fixed through bolt 5, gasket 11 and nut 12; housing 1, bushing 2, sealing disc 3, base 6, sliding sleeve 9 are machined parts; bushing 2 is arranged at the top center position of housing 1;

[0031] Housing 1 is a cylindrical part, which is hollow inside, and a flange is arranged at the bottom, the flange is perpendicular to the side wall of housing 1, and a plurality of housing bolt holes 26 are uniformly arranged on the flange; two circular housing air vent holes 25 are symmetrically arranged on the side wall of housing 1, a machining hole is arranged at the top of housing 1, and housing internal thread 22 is arranged in the machining hole.

[0032] The bushing 2 is an equal-thickness cylindrical part, provided with a guide hole 28 inside and a bushing flange 29 at the bottom, and provided with a bushing external thread 21 outside the side wall; the bushing 2 is installed on the top of the shell 1 by connecting the bushing external thread 21 with the shell internal thread 22.

[0033] The sealing disc 3 is a disc-shaped part, provided with a guide shaft at the center of one side of the disc, which is perpendicular to the disc; the spring 4 is installed outside the guide shaft, and the guide shaft of the sealing disc with the spring 4 is inserted into the guide hole 28 of the bushing 2; the sealing disc 3, the spring 4, the bushing 2 and the shell 1 form the upper assembly of the application. The base 6 is a cylindrical part with a hollow structure inside for installing the sliding sleeve 9, and is provided with a flange flange at the top, which is perpendicular to the side wall of the base 6, and is provided with a plurality of base bolt holes 27 on the flange flange, which are distributed correspondingly to the shell bolt holes 26 on the flange flange of the shell 1; the inner side of the flange flange is provided with an annular groove area for limiting the sliding sleeve 9.

[0034] The sliding sleeve 9 is a cylindrical part, provided with an annular shoulder at the top, and provided with a sealing inclined groove 23 on the upper end surface of the annular shoulder and a sealing straight groove 24 at the bottom area; the first sealing ring 7 is installed in the sealing inclined groove 23 for sealing between the sealing disc 3 and the sliding sleeve 9; the first sealing ring 7 is in a stretched state in the sealing inclined groove 23, and the reaction force of the sealing inclined groove 23 on the first sealing ring 7 can hinder the upward movement trend of the first sealing ring 7, preventing the first sealing ring 7 from falling off; the second sealing ring 8 is installed in the sealing straight groove 24 for sliding sealing between the sliding sleeve 9 and the side wall of the base 6; the sliding sleeve 9 is installed in the base 6 from top to bottom and is concentric with the base 6, and the sliding sleeve shoulder is placed in the annular groove inside the base flange flange, and the gravity of the sliding sleeve 9 can overcome the friction between the second sealing ring 8 and the inner wall of the base 6, and move linearly in the base 6; the second sealing ring 8 is in contact with the sealing straight groove 24 and the inner wall of the base 6 at the same time to ensure the sealing performance. The first sealing ring 7, the second sealing ring 8, the sliding sleeve 9 and the base 6 form the lower assembly of the application.

[0035] The flange flange of the base 6 is in butt joint with the flange flange of the shell 1, and the sizes are matched; the shell bolt holes 26 are positioned in combination with the base bolt holes 27; the bolt 5, the gasket 11 and the nut 12 connect the upper assembly and the lower assembly of the application into a whole, and the upper assembly and the lower assembly remain coaxial; the spring 4 is placed between the lower surface of the bushing flange 29 and the upper surface of the sealing disc 3 and is in a compressed state, and the compression amount of the spring 4 is adjusted by rotating the bushing 2, and then the opening pressure of the safety valve is adjusted.

[0036] When the aircraft is in normal flight state, the function of the present application is the same as the existing safety valve. Once the gas pressure in the fuel tank exceeds the set value, the sealing disc 3 is pushed open and the fuel tank gas pressure is released. The gas is discharged from the through-hole 25 in the shell, as shown in Figure 3 When the aircraft is in inverted flight state, the device is immersed in fuel. At this time, the fuel gravity acts on the lower surface of the sealing disc 3. If the fuel gravity acting on the sealing disc 3 is less than the spring force of the spring 4, the sealing disc 3 does not displace, and the device does not leak. If the fuel gravity acting on the sealing disc 3 is greater than the spring force of the spring 4, the sealing disc 3 is pushed open, and the spring 4 is further compressed. At this time, the sliding sleeve 9 is always pressed against the lower surface of the sealing disc 3 due to gravity and moves together with the sealing disc 3. The first sealing ring 7 blocks the fuel from flowing out of the gap between the sealing disc 3 and the sliding sleeve 9. The second sealing ring 8 blocks the fuel from flowing out of the gap between the outer wall of the sliding sleeve 9 and the inner wall of the base 6. The fuel leakage gap is sealed by the sealing ring. At this time, the working state of the device is as shown in Figure 4 Therefore, the present application can prevent fuel from flowing out of the fuel tank when the aircraft is in inverted flight state. When the aircraft returns to normal flight state, the sliding sleeve 9 falls back due to gravity, and the sealing disc 3 resets due to the spring force. The present application returns to the Figure 2 state.

[0037] The surface roughness of all sealing grooves of the present application is required to be high to avoid damage to the sealing ring.

[0038] The above-described embodiments of the present application do not constitute a limitation on the scope of protection of the present application.

Claims

1. A gas safety valve with a liquid-blocking function for an aircraft inverted flight condition, characterized in that: The gas safety valve comprises: an upper assembly and a lower assembly; The upper component comprises: a housing (1), a bushing (2), a sealing disc (3), and a spring (4); The lower component comprises: a sliding sleeve (9), a base (6), a first sealing ring (7), and a second sealing ring (8); The upper component and the lower component are connected and fixed by bolts (5), washers (11) and nuts (12); the bushing (2) is arranged at the top center of the housing (1); the end of the guide shaft of the sealing disk (3) passes through the center of the bushing (2); A sliding sleeve (9) is arranged inside the base (6).

2. The gas safety valve according to claim 1, characterized in that The shell (1) is a cylindrical part with a hollow structure inside. A flange is provided at the bottom. The flange is perpendicular to the side wall of the shell (1). A number of shell bolt holes (26) are evenly distributed on the flange. Two circular shell vent holes (25) are symmetrically provided on the side wall of the shell (1). A machined hole is provided on the top of the shell (1), and a shell internal thread (22) is provided in the machined hole.

3. The gas safety valve according to claim 1, characterized in that The bushing (2) is a cylindrical part of equal thickness, with a guide hole (28) provided inside, a bushing flange (29) provided at the bottom, and a bushing external thread (21) provided on the outer side of the bushing side wall; the bushing (2) is installed on the top of the shell (1) through the connection between the bushing external thread (21) and the shell internal thread (22).

4. The gas safety valve according to claim 1, characterized in that The sealing disc (3) is a disc-shaped part. A guide shaft is arranged on one side of the center of the disc. The guide shaft is perpendicular to the disc. The spring (4) is installed on the outside of the guide shaft. The sealing disc guide shaft with the spring (4) is inserted into the guide hole (28) of the bushing (2).

5. The gas safety valve according to claim 1, characterized in that: The base (6) is a cylindrical part with an internal hollow structure for mounting a sliding sleeve (9). A flange flange is provided on the top. The flange flange is perpendicular to the side wall of the base (6). A plurality of base bolt holes (27) are evenly distributed on the flange flange. The distribution of the base bolt holes (27) corresponds to the housing bolt holes (26) on the flange flange of the housing (1). An annular groove area is provided on the inner side of the flange flange for limiting the sliding sleeve (9).

6. The gas safety valve according to claim 1, characterized in that The sliding sleeve (9) is a cylindrical part, with an annular boss provided on the top, a sealing inclined groove (23) provided on the upper end surface of the annular boss, and a sealing straight groove (24) provided on the bottom area; The first sealing ring (7) is installed in the sealing inclined groove (23) and is used for sealing between the sealing disc (3) and the sliding sleeve (9); the first sealing ring (7) is in a stretched state in the sealing inclined groove (23); The second sealing ring (8) is installed in the sealing straight groove (24) and is used for sliding sealing between the sliding sleeve (9) and the side wall of the base (6); The sliding sleeve (9) is installed in the base (6) from top to bottom and is concentric with the base (6). The sliding sleeve boss is placed in the annular groove on the inner side of the base flange. The weight of the sliding sleeve (9) can overcome the friction between the second sealing ring (8) and the inner wall of the base (6), and the sliding sleeve (9) moves in a straight line in the base (6). The second sealing ring (8) contacts the sealing straight groove (24) and the inner wall of the base (6) simultaneously.

7. The gas safety valve according to claim 1, characterized in that The flange of the base (6) is butted against the flange of the shell (1) and the sizes are matched; the bolt holes (26) of the shell and the bolt holes (27) of the base are aligned and positioned; the bolts (5), the washers (11) and the nuts (12) connect the upper assembly and the lower assembly into a whole, and the upper assembly and the lower assembly remain coaxial.

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