Gas inlet float valve integrating ventilation, oil-gas two-way sealing and pressure maintaining

Abstract

The invention belongs to the technical field of aviation fuel systems, and provides a gas inlet float valve integrating ventilation, oil-gas double sealing and pressure maintaining, the gas inlet float valve comprises a shell, a valve seat, a valve assembly and a float assembly, the bottom of the shell is provided with a lower connector connected with a refueling pipeline, the valve seat is installed above the position, corresponding to the lower connector, of the shell, and the shell and the valve seat jointly form a valve element movement cavity; the valve assembly comprises a valve element and a valve rod, the upper side ring face of the valve element is matched with the top of the inner wall of the valve element movement cavity to form sealing, the bottom of the valve element is matched with the bottom of the inner wall of the valve element movement cavity to form sealing, and a gap is formed between the middle inner diameter of the valve element movement cavity and the outer diameter of the valve element. The top of the valve element is fixedly connected with the valve rod, the valve rod extends out of a through hole in the top of the valve seat, a small step face is arranged on the outer side of the extending part of the valve rod, the floater assembly is sleeved outside the small step face of the valve rod in a clearance mode, and the inner diameter of the floater assembly is smaller than the outer diameter of a large step face below the small step face of the valve rod. A spring is arranged between the top of the floater assembly and the valve rod. According to the invention, the requirements of opening ventilation, closing sealing, closing pressure maintaining and the like required by the system can be met under various working conditions of positive / negative pressure and different liquid levels, and the functions of oil-gas two-way sealing, ventilation and pressure maintaining can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation fuel system, and relates to a multifunctional valve used in a fuel filling pipeline in a fuel tank, and specifically to an air intake float valve integrating ventilation, oil and gas double sealing, and pressure maintenance. Background Art

[0002] A large section of the aircraft's refueling line is located in the fuel tank. In order to increase the flight range and use the fuel in the tank reasonably, air needs to be allowed to enter the refueling line during flight so that the residual fuel in the refueling line can be discharged back to the tank through the drain valve. Therefore, a valve product is needed to be installed in the refueling line to complete this task to minimize unusable fuel; during refueling and pressure / suction draining, the valve product should be closed when subjected to a large positive or negative pressure difference (pressure / suction) to prevent the pressure difference from failing to form; when the oil surface submerges the refueling line, the valve product should be closed to prevent the fuel from flowing back into the line.

[0003] Currently, no valve product can automatically complete this task, and since the refueling pipeline is located in the fuel tank, this valve product cannot be controlled by a solenoid valve because an electric plug cannot be introduced into the fuel tank. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an air intake float valve with ventilation, oil and gas dual sealing and pressure maintenance. The valve can be used as a conventional air intake valve with ventilation and two-way sealing to block oil, and can be installed and used in the refueling pipeline in the fuel tank.

[0005] The technical solution of the present invention is as follows:

[0006] An intake float valve with ventilation, oil and gas dual sealing and pressure maintenance, comprising a shell, a valve seat, a valve assembly and a float assembly, a lower interface connected to a refueling pipeline is provided at the bottom of the shell, a valve seat is installed above the shell corresponding to the lower interface, and the shell and the valve seat jointly form a valve core movement chamber; the valve assembly comprises a valve core and a valve stem, an upper side annular surface of the valve core cooperates with the top of the inner wall of the valve core movement chamber to form a seal, the bottom of the valve core cooperates with the bottom of the inner wall of the valve core movement chamber to form a seal, and a gap is provided between the middle inner diameter of the valve core movement chamber and the outer diameter of the valve core; the top of the valve core is fixedly connected to the valve stem, the valve stem extends from the through hole at the top of the valve seat, a small step surface is provided on the outer side of the extended part of the valve stem, a gap sleeve of the float assembly is placed outside the small step surface of the valve stem, and the inner diameter of the float assembly is smaller than the outer diameter of the large step surface below the small step surface of the valve stem; a spring is provided between the top of the float assembly and the valve stem.

[0007] Furthermore, it also includes a spring seat, which is fixed on the top of the valve stem of the valve assembly. The spring is arranged between the spring seat and the float assembly, and the spring is sleeved outside the valve stem. The spring is a compression spring.

[0008] Furthermore, the spring force of the spring matches the gravity of the valve assembly, so that the valve assembly is located in the middle of the valve core movement chamber when not subjected to external force.

[0009] Furthermore, an outer circular structure is provided on the outer side of the shell, and a float core on the outer side of the float assembly is arranged above the outer circular structure on the outer side of the shell.

[0010] Furthermore, a guide groove is provided at the bottom of the outer circular structure, a through hole is provided at the bottom of the guide groove, and the through hole penetrates the shell.

[0011] Furthermore, the top and bottom through holes of the valve core movement cavity are both oblique conical surfaces, the top of the valve core is a conical surface, and the bottom side of the valve core is also a conical surface.

[0012] Furthermore, when the oil in the refueling line is drained, the oil pressure in the refueling line is low, and the oil level in the fuel tank is below the air intake float valve, so that the valve assembly is not under pressure or is under low pressure, and the valve core is in the middle of the valve core movement chamber. At this time, the valve core movement chamber is connected from top to bottom, and the air above the fuel tank enters the refueling line from the valve core movement chamber to discharge the residual oil in the refueling line.

[0013] Furthermore, when refueling the fuel tank through the refueling pipeline, positive pressure oil passes through the refueling pipeline. At this time, the valve assembly is subjected to downward pressure from the lower interface. The downward pressure is greater than or equal to the weight of the valve core + the weight of the float structure, so that the valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the refueling pipeline from flowing out of the intake float valve.

[0014] Furthermore, when the oil in the fuel tank is sucked through the refueling line, negative pressure oil passes through the refueling line. At this time, the valve assembly is subjected to upward pressure from the upper direction of the shell. The upper pressure + the gravity of the valve assembly is greater than or equal to the spring force, so that the valve core is in the lower limit position, thereby closing the valve core movement cavity, preventing air in the upper part of the fuel tank from entering the refueling line, resulting in a vacuum cannot be generated and the oil suction fails.

[0015] Furthermore, when the oil level in the fuel tank exceeds the installation position of the intake float valve, the float assembly is affected by the buoyancy of the oil, and the float buoyancy is greater than or equal to the weight of the valve assembly + the weight of the float structure. The valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the fuel tank from entering the refueling pipeline.

[0016] Technical effects of the present invention:

[0017] The above invention can meet the requirements of opening for ventilation, closing for sealing, closing for pressure maintenance and the like required by the system under various working conditions of positive / negative pressure and different liquid levels, and can realize the oil-gas two-way sealing, ventilation and pressure maintenance functions. When refueling, the present invention can ensure that the valve structure is automatically closed, thereby preventing the oil in the refueling line from leaking. When pumping oil, the present invention can ensure that the valve structure is automatically closed, thereby preventing leaks from appearing in the refueling line. When the fuel tank is full, the present invention can ensure that the valve is automatically closed, preventing the oil in the tank from flowing back into the refueling line. When emptying the refueling line, the valve of the present invention opens automatically, allowing air to enter the refueling line, thereby allowing all the fuel in the refueling line to be discharged, preventing oil accumulation and waste, and improving the efficiency of aircraft use. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a schematic diagram showing that the valve core of the air intake float valve of the present invention is in a middle position;

[0020] Figure 2 It is a schematic diagram showing that the valve core of the air intake float valve of the present invention is in the upper limit position;

[0021] Figure 3 It is a schematic diagram of the valve core of the air intake float valve of the present invention being in the lower limit position;

[0022] Among them, 1-housing; 2-valve seat; 3-valve assembly; 4-spring seat; 5-filter assembly; 6-spring; 7-float assembly; 8-elastic retaining ring; 9-sealing ring. DETAILED DESCRIPTION

[0023] This section is an embodiment of the present invention, which is used to explain and illustrate the technical solution of the present invention. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the orientations or positional relationships in the accompanying 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 case referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implying the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be interpreted in a broad sense, for example, it can be a fixed connection, a detachable connection or an integrated connection; it can be a mechanical connection or a point connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0026] Embodiment 1:

[0027] An air intake float valve with ventilation, oil and gas double sealing and pressure maintenance, comprising a shell 1, a valve seat 2, a valve assembly 3 and a float assembly 7. The bottom of the shell 1 is provided with a lower interface connected to a refueling pipeline, and the valve seat 2 is installed above the shell 1 corresponding to the lower interface, and the shell 1 and the valve seat 2 jointly form a valve core movement chamber; the valve assembly 3 comprises a valve core and a valve stem, the upper side annular surface of the valve core cooperates with the top of the inner wall of the valve core movement chamber to form a seal, the bottom of the valve core cooperates with the bottom of the inner wall of the valve core movement chamber to form a seal, and a gap is provided between the middle inner diameter of the valve core movement chamber and the outer diameter of the valve core; the top of the valve core is fixedly connected to the valve stem, the valve stem extends from the through hole at the top of the valve seat 2, and a small step surface is provided on the outer side of the extended part of the valve stem, the float assembly 7 is gap-covered outside the small step surface of the valve stem, and the inner diameter of the float assembly 7 is smaller than the outer diameter of the large step surface below the small step surface of the valve stem; a spring 6 is provided between the top of the float assembly 7 and the valve stem.

[0028] It also includes a spring seat 4, which is fixed on the top of the valve stem of the valve assembly 3. A spring 6 is arranged between the spring seat 4 and the float assembly 7. The spring 6 is sleeved outside the valve stem, and the spring 6 is a compression spring.

[0029] The spring force of the spring 6 matches the gravity of the valve assembly 3, so that the valve assembly 3 is located in the middle of the valve core movement chamber in the absence of external force.

[0030] An outer circular structure is provided on the outer side of the housing 1 , and a float core 9 on the outer side of the float assembly 7 is arranged above the outer circular structure on the outer side of the housing 1 .

[0031] A guide groove is provided at the bottom of the outer circular structure, and a through hole is provided at the bottom of the guide groove, and the through hole penetrates the shell 1.

[0032] The top and bottom through holes of the valve core movement cavity are both oblique conical surfaces, the top of the valve core is a conical surface, and the bottom side of the valve core is also a conical surface.

[0033] When the oil in the refueling line is drained, the oil pressure in the refueling line is low, and the oil level in the fuel tank is below the air inlet float valve, so that the valve assembly 3 is not under pressure or is under low pressure, and the valve core is in the middle of the valve core movement chamber. At this time, the valve core movement chamber is connected from top to bottom, and the air above the fuel tank enters the refueling line from the valve core movement chamber to discharge the residual oil in the refueling line.

[0034] When refueling the fuel tank through the refueling pipeline, positive pressure oil flows through the refueling pipeline. At this time, the valve assembly 3 is subjected to downward pressure from the lower interface. The downward pressure is greater than or equal to the weight of the valve core + the weight of the float structure, so that the valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the refueling pipeline from flowing out of the intake float valve.

[0035] When the oil in the fuel tank is sucked through the refueling line, negative pressure oil passes through the refueling line. At this time, the valve assembly 3 is subjected to upward pressure from the upper direction of the shell. The upper pressure + the gravity of the valve assembly 3 is greater than or equal to the spring force, so that the valve core is in the lower limit position, thereby closing the valve core movement cavity, preventing the air above the fuel tank from entering the refueling line, resulting in the failure of generating a vacuum and thus the failure of oil suction.

[0036] When the oil level in the oil tank exceeds the installation position of the intake float valve, the float assembly 7 is affected by the buoyancy of the oil, and the float buoyancy is greater than or equal to the gravity of the valve assembly 3 + the gravity of the float structure. The valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the oil tank from entering the refueling pipeline.

[0037] Embodiment 2:

[0038] Figure 1 The present invention is a structural principle diagram of an air-ventilating, oil-gas dual-sealing, pressure-maintaining air intake float valve according to an embodiment of the present invention.

[0039] Among them, the housing 1; the valve seat 2; the valve assembly 3; the spring seat 4; the filter assembly 5; the spring 6; the float 6; the float core 7; the elastic retaining ring 9; and the sealing ring 10.

[0040] The present invention reasonably designs the structures of the valve assembly, the housing assembly and the support frame. The valve assembly and the housing are sealed by wire, and the valve assembly and the support frame are sealed by hard sealing and soft contact, so as to ensure the sealing of the product when both sides are closed.

[0041] The invention ensures that the product is in a normally open state by rationally designing the spring, and does not close under a relatively small negative pressure range, which does not affect the ventilation function of the product, and closes and seals under a relatively large negative pressure, which does not affect the sealing of the product;

[0042] The shell assembly uses non-metallic materials to connect the metal materials on both sides to ensure the connection between internal parts and pipelines, as well as the welding of external parts and filters;

[0043] The float structure is reasonably designed, and a gap is set between the float structure and the valve assembly. When the valve core is in the middle position, the bottom of the float structure contacts the shell, the spring is compressed between the float structure and the valve core, and the valve core is in the middle position under the balance of spring force and gravity; when the valve core is in the lower limit position, the pressure + gravity is required to be greater than or equal to the spring force; and when the valve core is in the upper limit position under the action of pressure, the pressure below is greater than or equal to the weight of the valve core + the weight of the float structure; when the valve core is in the upper limit position under the action of the float structure, the buoyancy of the float structure is greater than or equal to the weight of the valve core + the weight of the float structure. When the oil level reaches a certain level, the product is closed without leakage. When the oil level is low, the float does not affect the opening and closing of the product. The connection between the float structure and the valve core has a step, which is set on the valve core to ensure that when the valve core is upward, the valve core carries the float structure upward through the step, and the gravity of the float structure also acts on the valve core through the step of the valve core.

[0044] Reasonable design of the valve seat and support frame, the structure of the shell assembly, and the structure of the float assembly and the shell assembly ensures that the product can automatically find the upper and lower seals.

[0045] The inlet uses a filter to filter impurities inside the oil tank to prevent product clogging.

[0046] A groove is set in the shell assembly and an elastic retaining ring is installed to limit the up and down movement of the support frame without affecting the discharge of oil above the product.

[0047] Type II seals are set at the shell assembly and the support frame to maintain the sealing of the product, and a small movement of the support frame will not affect its sealing.

[0048] Multiple weight-reducing holes and drainage holes are provided in the shell assembly to reduce weight and prevent oil or water droplets from remaining on the product.

[0049] The air intake float valve of the present invention is arranged in the refueling pipeline, specifically at the highest point of the refueling pipeline in the fuel tank, and includes the following four use states:

[0050] 1. When the valve core is not under pressure or is under low pressure, the valve core is in the middle state, and the valve body is ventilated from top to bottom. At this time, it is used for top air intake to facilitate the discharge of fuel in the refueling line.

[0051] 2. When refueling, positive pressure oil passes through the refueling pipeline. At this time, the valve core is under pressure from below, which makes it in the upper limit position, thereby closing the valve body and preventing the oil in the refueling pipeline from flowing out of the valve.

[0052] 3. When the refueling line is absorbing oil, negative pressure is transmitted in the refueling line. At this time, the valve core is under pressure from above, causing it to be in the lower limit position, thereby closing the valve body to prevent air from above from entering the refueling line, resulting in a vacuum that cannot be generated and oil absorption fails.

[0053] 4. When the oil level in the oil tank exceeds the position of this valve body, the valve core is in the upper limit position through the action of the float, thereby closing the valve body to prevent the oil in the oil tank from entering the refueling pipeline.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. An air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance, characterized in that: The invention comprises a housing (1), a valve seat (2), a valve assembly (3) and a float assembly (7); the bottom of the housing (1) is provided with a lower interface for connecting to a refueling pipeline; the valve seat (2) is installed above the housing (1) corresponding to the lower interface; the housing (1) and the valve seat (2) together form a valve core movement chamber; the valve assembly (3) comprises a valve core and a valve stem; the upper side annular surface of the valve core cooperates with the inner wall top of the valve core movement chamber to form a seal; the bottom of the valve core cooperates with the inner wall bottom of the valve core movement chamber to form a seal; a gap is provided between the middle inner diameter of the valve core movement chamber and the outer diameter of the valve core; the top of the valve core is fixedly connected to the valve stem; the valve stem extends from a through hole at the top of the valve seat (2); a small step surface is provided on the outer side of the extended part of the valve stem; the float assembly (7) is spaced outside the small step surface of the valve stem; the inner diameter of the float assembly (7) is smaller than the outer diameter of the large step surface below the small step surface of the valve stem; a spring (6) is provided between the top of the float assembly (7) and the valve stem; the spring (6) is a compression spring.

2. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1 is characterized in that: The spring force of the spring (6) matches the gravity of the valve assembly (3), so that the valve assembly (3) is located in the middle of the valve core movement chamber when not subjected to external force.

3. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1 is characterized in that: It also includes a spring seat (4), which is fixed on the top of the valve stem of the valve assembly (3), a spring (6) is arranged between the spring seat (4) and the float assembly (7), and the spring (6) is sleeved outside the valve stem.

4. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1 is characterized in that: An outer circular structure is provided on the outer side of the shell (1), and a float core on the outer side of the float assembly (7) is arranged above the outer circular structure on the outer side of the shell (1).

5. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 4, characterized in that: A guide groove is provided at the bottom of the outer circular structure, and a through hole is provided at the bottom of the guide groove, and the through hole penetrates the shell (1).

6. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1, characterized in that: The top and bottom through holes of the valve core movement cavity are both oblique conical surfaces, the top of the valve core is a conical surface, and the bottom side of the valve core is also a conical surface.

7. The air inlet float valve with integrated ventilation, oil and gas double sealing and pressure maintenance according to claim 2, characterized in that: When the oil in the refueling pipeline is emptied, the oil pressure in the refueling pipeline is low, and the oil level in the oil tank is located below the air inlet float valve, so that the valve assembly (3) is not under pressure or is under low pressure, and the valve core is in the middle of the valve core movement chamber. At this time, the valve core movement chamber is connected from top to bottom, and the air above the oil tank enters the refueling pipeline from the valve core movement chamber to discharge the residual oil in the refueling pipeline.

8. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1, characterized in that: When refueling the fuel tank through the refueling pipeline, positive pressure oil flows through the refueling pipeline. At this time, the valve assembly (3) is subjected to downward pressure from the lower interface. The downward pressure is greater than or equal to the weight of the valve core + the weight of the float structure, so that the valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the refueling pipeline from flowing out of the air inlet float valve.

9. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1, characterized in that: When the oil in the oil tank is sucked through the refueling pipeline, negative pressure oil passes through the refueling pipeline. At this time, the valve assembly (3) is subjected to upward pressure from the upper direction of the shell. The upward pressure + the gravity of the valve assembly (3) is greater than or equal to the spring force, so that the valve core is in the lower limit position, thereby closing the valve core movement cavity, preventing the air in the upper part of the oil tank from entering the refueling pipeline, resulting in the inability to generate a vacuum and thus the failure of oil suction.

10. The air inlet float valve with ventilation, oil and gas dual sealing and pressure maintenance according to claim 1, characterized in that: When the oil level in the oil tank exceeds the installation position of the intake float valve, the float assembly (7) is subjected to the buoyancy of the oil, and the float buoyancy is greater than or equal to the weight of the valve assembly (3) + the weight of the float structure, and the valve core is in the upper limit position, thereby closing the valve core movement cavity and preventing the oil in the oil tank from entering the refueling pipeline.

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