A pilot pressure regulating combination device

Abstract

The present application belongs to the technical field of aviation fuel tank pressure control, and aims to solve the technical problems of single function of existing pressure regulating device, non-selectivity of attitude pressure regulation, and insufficient redundancy of overpressure protection. The pilot type pressure regulating combination device disclosed in the present application integrates four types of functional components, i.e. low-pressure safety valve, high-pressure safety valve, anti-vacuum valve and fueling exhaust valve. Selective attitude pressure regulation is realized by using a steel ball limiting baffle, three-stage overpressure protection is realized by designing the area difference of the valves, and the fueling exhaust channel is controlled by an electromagnetic valve. The present application realizes full-scene coverage of flight pressure regulation, fueling protection and ground pressure relief, can effectively balance the pressure of gas inside and outside the tank, avoids damage of the tank due to excessive pressure difference, ensures normal fueling and oil supply, greatly improves the reliability of the fuel system, reduces the connection points of the system pipeline, and reduces the overall weight. The present application is suitable for pressure control of fuel tanks of various civil and military aircrafts.

Description

Technical Field

[0001] This invention belongs to the technical field of aircraft fuel system pressure regulating devices, specifically relating to a pilot-operated pressure regulating combination device. Background Technology

[0002] Existing pressure regulating devices only support pressure regulation during flight. Ground refueling requires additional valve assemblies, resulting in a complex and heavy system. Existing ball-type pressure regulating devices trigger pressure increase in all attitudes, which is unnecessary and increases the pressure load on the fuel tank during aircraft pitch-up conditions. Existing pressure regulating devices only have two levels of overpressure protection, which is not reliable enough and cannot meet the high redundancy requirements of aviation products. The purely mechanical passive pressure regulating mode cannot achieve active intervention, and ground maintenance operations are cumbersome. The anti-clogging protection and sealing design only covers the core pressure regulating components, and there is room for improvement in the overall system reliability. Summary of the Invention

[0003] To address the aforementioned shortcomings of existing technologies, this invention provides a pilot-operated pressure regulating combination device. While retaining the core advantages of high reliability in mechanical attitude adaptive pressure regulation, it integrates refueling and venting functions, enabling precise pressure adjustment in all scenarios, while effectively improving the overall reliability of the system and the convenience of ground maintenance.

[0004] The technical solution adopted in this invention is as follows: A pilot-operated pressure regulating combination device includes a housing assembly and a valve seat fixedly installed inside the housing assembly. The housing assembly has at least one medium inlet and at least one medium outlet. A low-pressure safety valve assembly, a high-pressure safety valve assembly, an anti-vacuum valve assembly, and an electrically controlled exhaust valve assembly are integrated and installed on the valve seat. A pilot control module is provided above the low-pressure safety valve assembly. The pilot control module includes a valve seat fixed on the valve seat, a rolling trigger movably disposed on the valve seat, a pilot valve assembly that slides with the valve seat, and an elastic reset member for providing a reset force to the pilot valve assembly. The rolling trigger is configured to generate displacement with changes in the device's posture, triggering the opening and closing action of the pilot valve assembly through displacement changes, thereby precisely adjusting the opening pressure of the low-pressure safety valve assembly. The pressure relief channel of the electrically controlled exhaust valve assembly is controllably connected to an electrically controlled valve and is configured to actively open or close according to different working scenarios, realizing the functions of ground refueling and exhaust, full oil overflow, and ground pressure relief.

[0005] The rolling trigger is a steel ball. The pilot control module also includes a ball seat fixedly mounted on the valve seat and a top cover fixedly mounted on the housing assembly. The upper surface of the ball seat is an inclined structure, and the steel ball can roll freely along the inclined surface of the ball seat. The top cover is provided with a limiting structure on the side facing the steel ball. The limiting structure is configured to limit the rolling range of the steel ball. Only when the tilt angle of the device reaches a preset threshold, the steel ball rolls away from the trigger end of the pilot valve assembly, so that the pilot valve assembly closes the pressure relief hole under the action of the elastic reset member. The inner cavity of the low-pressure safety valve assembly establishes back pressure to increase the opening pressure.

[0006] The inclined plane of the ball seat has an inclination angle of 15°, and the preset threshold is 15°. The preset threshold is the tilt angle of the device relative to the horizontal position. The elastic reset element is a pilot valve spring, which is coaxially installed in the inner cavity of the pilot valve assembly. The limiting structure of the top cover is a baffle arranged along the rear side of the steel ball. The baffle is configured to restrict the steel ball to roll only in the forward, left, and right directions, so as to prevent the steel ball from moving backward and triggering pressure adjustment when the device is in a nose-up attitude. The steel ball is only allowed to roll forward, left, and right when the aircraft is in a nose-down or lateral flight attitude.

[0007] The inner cavity of the low-pressure safety valve assembly has a smaller effective area than its inlet pressure-sensing area. It is configured such that even if the pressure relief hole is closed and back pressure is established, the low-pressure safety valve assembly can still be forced open by the medium pressure when the medium pressure exceeds the opening pressure of the high-pressure safety valve assembly, thus forming a dual-redundant safety structure.

[0008] Filter elements are installed at the medium inlet side of the low-pressure safety valve assembly, the medium inlet side of the electrically controlled exhaust valve assembly, and the pipe joint at the medium outlet, forming a full-path impurity protection structure to prevent the pilot orifice from becoming clogged. Specifically, the filters installed on the inlet side of the low-pressure safety valve assembly and the electrically controlled exhaust valve assembly prevent impurities from entering from the inlet and clogging the pilot orifice; the filter installed on the pipe joint on the outlet side of the device prevents impurities from flowing back from the outlet and clogging the pilot orifice.

[0009] The mating surfaces of the housing assembly and the valve seat, the high-pressure safety valve assembly and the valve seat, the low-pressure safety valve assembly and the valve seat, the electrically controlled exhaust valve assembly and the valve seat, and the anti-vacuum valve assembly and the housing assembly are all equipped with independent sealing elements, which can realize pressure isolation of each functional chamber and effectively avoid pressure crosstalk.

[0010] The housing assembly includes a lower housing and an upper housing fixedly connected by screws and washers. The medium inlet is located in the lower housing, and the medium outlet is located in the upper housing. Both the low-pressure safety valve assembly and the high-pressure safety valve assembly are fixedly installed in the upper housing, and the anti-vacuum valve assembly is installed in the lower housing. The anti-vacuum valve assembly is configured to automatically open to replenish air when the external pressure is higher than the internal pressure. The high-pressure safety valve assembly is configured as a redundant backup of the low-pressure safety valve assembly. It automatically opens when the low-pressure safety valve assembly is stuck or has insufficient air intake capacity to maintain stable internal pressure.

[0011] When the aircraft is in a horizontal or vertical position, the steel ball is pressed down on the pilot valve assembly by gravity, and the gas in the cavity of the low-pressure safety valve assembly can be depressurized through the pilot hole. At this time, the opening pressure of the low-pressure safety valve assembly is in the low threshold range. When the aircraft tilts more than 15°, the steel ball rolls off the pilot valve assembly along the ball seat slope. The pilot valve assembly is then pressed against the ball seat by the spring force of the pilot valve spring, closing the depressurization hole. Back pressure is established in the cavity of the low-pressure safety valve assembly, which raises its opening pressure to the high threshold range, thus achieving adaptive adjustment of the pressure regulation under changes in flight attitude.

[0012] The low-pressure safety valve assembly adopts a redundancy design: its inner cavity pressure-bearing area is smaller than the inlet pressure-sensing area. Even if the inner cavity pressure relief hole is closed and the back pressure is not released, when the oil tank pressure continues to rise to exceed the opening pressure of the high-pressure safety valve assembly, the low-pressure safety valve assembly can still be forced to open to replenish air to the oil tank, thus avoiding the failure of a single pressure regulation path.

[0013] The internal pressure relief channel of the electronically controlled exhaust valve assembly is controlled by a solenoid valve. The pressure-bearing area of ​​the internal cavity of the electronically controlled exhaust valve assembly is larger than the pressure-sensing area at the inlet. If the internal pressure is not relieved, the electronically controlled exhaust valve assembly cannot open. When refueling on the ground, the solenoid valve is energized to open the internal valve, the pressure relief channel is open, and the electronically controlled exhaust valve assembly can open normally to achieve exhaust. If the refueling shut-off valve fails after the fuel tank is full, the continuously injected fuel can be discharged through the refueling exhaust valve to achieve fuel tank overpressure protection. After the aircraft completes flight and lands, the solenoid valve can be energized to open the electronically controlled exhaust valve assembly, releasing excess pressure in the fuel tank.

[0014] The anti-vacuum valve assembly is installed on the lower housing. When the aircraft dives, the external air pressure rises sharply and exceeds the air pressure inside the fuel tank. The anti-vacuum valve assembly opens to replenish air into the fuel tank to prevent negative pressure damage. After the internal and external pressures are balanced, the anti-vacuum valve assembly resets and presses against the valve seat under the elastic force of the anti-vacuum spring.

[0015] The high-pressure safety valve assembly is a redundancy configuration device for the low-pressure safety valve assembly. When the low-pressure safety valve assembly is stuck or has insufficient air intake capacity, the high-pressure safety valve assembly automatically opens the air intake to maintain stable oil tank pressure.

[0016] The valve seat integrates four types of valve assemblies: a low-pressure safety valve assembly, a high-pressure safety valve assembly, a vacuum-proof valve assembly, and an electrically controlled exhaust valve assembly. The low-pressure safety valve assembly is equipped with a pilot attitude control structure, which adaptively adjusts the opening pressure of the low-pressure safety valve according to changes in aircraft attitude. The electrically controlled exhaust valve assembly is equipped with a solenoid valve control structure to control the opening and closing of the pressure relief channel within the refueling exhaust valve cavity. The vacuum-proof valve assembly is installed in the lower housing; when negative pressure occurs in the fuel tank, this assembly automatically opens to replenish air; after the pressure inside and outside the fuel tank is balanced, it resets and closes under spring force. The high-pressure safety valve assembly serves as a redundancy for the low-pressure safety valve assembly, providing backup pressure regulation capability in case of low-pressure safety valve failure. The electrically controlled valve is a solenoid valve, and its operating logic is set as follows: in ground refueling or ground depressurization scenarios, it is energized to open and conduct the electrically controlled exhaust valve assembly; in flight scenarios, it is de-energized and closed to prevent accidental depressurization of the fuel tank.

[0017] This application belongs to the field of aviation fuel tank pressure control technology, aiming to solve the technical problems of existing pressure regulating devices having single function, lack of selectivity in attitude pressure regulation, and insufficient redundancy in overpressure protection. The pressure regulating device disclosed in this application integrates four types of functional components: low-pressure safety valve, high-pressure safety valve, anti-vacuum valve, and electronically controlled exhaust valve. It uses a steel ball limit baffle to achieve selective attitude pressure regulation, realizing full-scenario coverage of flight pressure regulation, refueling protection, and ground pressure relief, which can effectively improve the reliability of the fuel system and reduce the overall weight.

[0018] The pilot-operated pressure regulating device of the present invention adopts a modular integrated design, and simultaneously installs a low-pressure safety valve assembly, a high-pressure safety valve assembly, a vacuum prevention valve assembly, and an electrically controlled exhaust valve assembly on the valve seat, thereby realizing four core functions: 1. All-attitude flight pressure regulation function: Retains the mechanical pressure regulation structure of steel ball-pilot valve linkage, optimizes the rolling logic of steel ball through top cover limit baffle, increases the opening pressure of low pressure safety valve only in the diving and side flight attitudes, and maintains normal pressure relief pressure in the pitching attitude, fully adapting to the needs of various flight attitudes. 2. Ground refueling protection function: The refueling vent valve is controlled by a solenoid valve. It actively vents air during refueling. If the refueling shut-off valve fails, the device can automatically overflow, effectively preventing the fuel tank from being damaged due to overpressure. 3. Convenient ground pressure relief function: After the aircraft lands, the refueling vent valve can be opened by power to quickly release the residual pressure in the fuel tank, greatly simplifying the ground maintenance operation process; 4. Multi-level redundancy safety functions: Through the design of low-pressure valve dual redundancy, high-pressure valve redundancy backup, full-path filter anti-clogging, independent chamber sealing and other designs, the reliability of system operation is improved in all aspects.

[0019] The beneficial effects of this invention are: Highly integrated design: The four functions of low-pressure safety regulation, high-pressure margin regulation, vacuum protection, and electronic exhaust protection are integrated into the same housing structure, which greatly reduces the space occupied by the fuel system pressure regulation module, reduces external pipeline connections, and lowers system maintenance costs.

[0020] Attitude adaptive pressure regulation: Through the mechanical sensing structure of the steel ball-pilot valve, it can automatically match the low-pressure safety valve opening pressure requirements under different aircraft attitudes without additional electronic control signals. The 15° tilt ball seat design and the limiting structure of the top cover baffle ensure the accuracy and reliability of attitude sensing, and are suitable for various maneuvering scenarios such as dive, side flight, and inverted flight.

[0021] Multiple redundancy safety design: The low-pressure safety valve has dual-path opening capability, and is equipped with an independent high-pressure safety valve as a backup. Together with the overpressure overflow function of the refueling and venting valve and the negative pressure protection function of the anti-vacuum valve, a multi-pressure protection system is formed, which greatly reduces the system risk caused by a single failure.

[0022] Full-scenario coverage and adaptation: It simultaneously meets the dynamic pressure regulation requirements during flight, the exhaust and overflow protection requirements during ground refueling, and the fuel tank depressurization requirements after landing, achieving pressure regulation and protection coverage for all usage scenarios.

[0023] Multi-stage anti-clogging design: Equipped with inlet and outlet dual-path filters, it can effectively block impurities and avoid clogging of the pilot hole, significantly improving the operational stability and service life of the device.

[0024] It adopts a dual control mode of mechanical + electrical: it retains the high reliability of mechanical voltage regulation, and can realize active function intervention through electrical control, thus taking into account both operational safety and ease of maintenance. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are only some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without inventive effort.

[0026] Figure 1 A perspective view of the pilot-operated voltage regulating assembly provided by the present invention; Figure 2 A cross-sectional view of the low-pressure valve assembly of the pilot-operated pressure regulating combination device provided by the present invention; Figure 3 A cross-sectional view of the high-pressure valve assembly of the pilot-operated pressure regulating combination device provided by the present invention; Figure 4 A cross-sectional view of the electrically controlled exhaust valve assembly of the pilot-operated pressure regulating combination device provided by the present invention; Figure 5 Cross-sectional view of the anti-vacuum valve assembly of the pilot-operated pressure regulating combination device provided by the present invention; Figure 6 A cross-sectional view of the solenoid valve assembly of the pilot-operated pressure regulating combination device provided by the present invention; Figure 7 This is a schematic diagram of the pilot-operated voltage regulating combination device provided by the present invention; Figure 8 for Figure 7 Cross-sectional view along the AA direction; Figure 9 for Figure 8 Cross-sectional view along the BB direction; Figure 10 for Figure 8 Cross-sectional view along the CC direction; Figure 11 for Figure 8 Cross-sectional view along the DD direction; Figure 12 for Figure 9 Structure diagram in the G direction; Figure 13 A schematic diagram of the structure of the solenoid valve assembly provided by the present invention; Figure 14 This is a state diagram of the pilot-operated pressure regulating assembly during aircraft flight. Figure 15 This is a state diagram of the pilot-operated pressure regulating assembly during aircraft inverted flight. Wherein: 1-Solenoid valve assembly, 2-Lower housing, 3-Valve seat, 4-Screw one, 5-Washer one, 7-Upper housing, 8-Low-pressure valve assembly, 9-Low-pressure valve spring, 10-Low-pressure valve gasket, 11-Pipe connector, 18-Pilot valve spring, 19-Pilot valve assembly, 20-Steel ball, 21-Top cover, 22-Ball seat, 23-Valve seat, 24-Screw two, 26-Washer two, 27-High-pressure valve gasket, 28-High-pressure valve assembly, 29-High-pressure valve spring, 33 - Electrically controlled exhaust valve assembly, 34 - Electrically controlled exhaust valve spring, 35 - Electrically controlled exhaust valve gasket, 36 - Spring seat, 37 - Gasket, 38 - Anti-friction ring, 39 - Anti-vacuum spring, 40 - Anti-vacuum valve assembly, A - Outlet 1, B - Outlet 2, C - Inlet 1, D - Inlet 2, 101 - Socket, 102 - Plug, 103 - Tail accessory, 104 - Base, 105 - Spring, 106 - Solenoid valve seat, 107 - Valve seat, 108 - Valve rod, 109 - Solenoid valve. Detailed Implementation

[0027] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. Exemplary embodiments may take many forms and should not be limited to the examples shown herein; rather, these embodiments are provided to make the disclosure of the invention more comprehensive and complete, thereby fully conveying the core concepts of the exemplary embodiments to those skilled in the art.

[0028] Please see Figure 1-15 A pilot-operated pressure regulating device includes a housing assembly and a valve seat 3 fixedly installed inside the housing assembly. The housing assembly has at least one medium inlet and at least one medium outlet. The valve seat 3 integrates and installs a low-pressure safety valve assembly 8, a high-pressure safety valve assembly 28, a vacuum anti-vacuum valve assembly 40, and an electrically controlled exhaust valve assembly 33. Specifically, the housing assembly includes a lower housing 2 and an upper housing 7. The lower housing 2, upper housing 7, and valve seat 3 are fixedly connected by screw 4 and washer 5. The middle part of the upper housing 7 and valve seat 3 is fixedly connected by screw 24 and washer 26. Medium inlet 1 C and inlet 2 D are located in the lower housing 2, and medium outlet 1 A and outlet 2 B are located in the upper housing 7. The low-pressure safety valve assembly 8 and the high-pressure safety valve assembly 28 are both fixedly installed in the upper housing 7. The anti-vacuum valve assembly 40 is configured to automatically open to replenish air when the external pressure is higher than the internal pressure of the device. The high-pressure safety valve assembly 28 serves as a redundant backup for the low-pressure safety valve assembly 8. When the low-pressure safety valve assembly 8 jams or has insufficient air intake, it will automatically open to maintain stable internal pressure. The low-pressure safety valve assembly 8 is equipped with a low-pressure valve spring 9 and a low-pressure valve gasket 10, and the high-pressure safety valve assembly 28 is equipped with a high-pressure valve spring 29 and a high-pressure valve gasket 27.

[0029] like Figure 2 , Figure 3 , Figure 9As shown, a pilot control module is installed above the low-pressure safety valve assembly 8. The pilot control module includes a valve seat 23 fixed on the valve seat, a rolling trigger movably mounted on the valve seat 23, a pilot valve assembly 19 slidingly engaged with the valve seat 23, and an elastic reset member for providing a reset force to the pilot valve assembly 19. The elastic reset member is a pilot valve spring 18. The pilot valve assembly 19 is installed in the guide groove of the valve seat 23, and the pilot valve spring 18 is built into the inner cavity of the pilot valve assembly 19, allowing the pilot valve to move freely within the guide groove of the valve seat 23. The rolling trigger is configured to move with changes in the device's posture, triggering the opening and closing of the pilot valve assembly 19 by means of this displacement change, thereby adjusting the opening pressure of the low-pressure safety valve assembly 8. The pressure relief channel of the electrically controlled exhaust valve assembly 33 is controllably connected to the electrically controlled valve 1, and can be actively opened or closed according to different working scenarios, thereby completing the functions of ground refueling and exhaust, full oil overflow, and ground pressure relief.

[0030] The rolling trigger is a steel ball 20. The pilot control module also includes a ball seat 22 fixedly installed on the valve seat 23 and a top cover 21 fixed on the housing assembly. The upper surface of the ball seat 22 is a slope structure, and the steel ball 20 can roll freely along the slope of the ball seat 22. The top cover 21 is provided with a limit structure on the side facing the steel ball. The limit structure is configured to limit the rolling range of the steel ball 20. Only when the tilt angle of the device reaches a preset threshold, the steel ball 20 rolls away from the trigger end of the pilot valve assembly 19, so that the pilot valve assembly 19 closes the pressure relief hole under the force of the pilot valve spring 18, and the inner cavity of the low-pressure safety valve assembly 8 establishes back pressure to increase the opening pressure.

[0031] The inclined plane of ball seat 22 has an inclination angle of 15°, and the preset threshold is the 15° tilt angle of the device relative to the horizontal position; the elastic reset element is the pilot valve spring 18, which is coaxially installed in the inner cavity of the pilot valve assembly 19; the limiting structure of the top cover 21 is a baffle arranged along the rear side of the steel ball, which is configured to restrict the steel ball 20 to roll only in the forward, left and right directions, so as to prevent the steel ball from moving backward when the device is in the head-up position, thereby triggering unnecessary pressure adjustment action.

[0032] When the device is placed vertically, the steel ball 20 presses down the pilot valve assembly 19, and the gas in the cavity of the low-pressure safety valve assembly 8 is configured to be depressurized through the pilot hole. When the device tilts at an angle greater than 15°, after the steel ball 20 rolls, the pilot valve assembly 19 is in contact with the ball seat 22 under the action of the pilot valve spring 18, closing the depressurization hole. Back pressure is established in the cavity of the low-pressure safety valve assembly, and the opening pressure of the low-pressure safety valve assembly increases. It is configured that when the oil tank pressure is greater than the opening pressure of the high-pressure safety valve assembly 28, the low-pressure safety valve assembly 8 opens to replenish the oil tank with gas.

[0033] The inner cavity of the low-pressure safety valve assembly 8 has a smaller effective area than its inlet pressure-sensing area. It is configured such that even if the pressure relief hole is closed and back pressure is established, the low-pressure safety valve assembly 8 can still be forced open by the medium pressure when the medium pressure exceeds the opening pressure of the high-pressure safety valve assembly 28, thus forming a dual-redundant safety structure.

[0034] Filter elements are installed at the medium inlet side of the low-pressure safety valve assembly 8, the medium inlet side of the electrically controlled exhaust valve assembly 33, and the pipe joint 11 at the medium outlet, forming a full-path impurity protection structure to prevent the pilot hole from becoming blocked.

[0035] like Figure 4 , Figure 10 As shown, the electrically controlled exhaust valve assembly 33 is placed inside the upper housing 7, and an electrically controlled exhaust valve spring 34 is provided on its inner side. A spring seat 36 is provided on the top of the electrically controlled exhaust valve spring 34. An electrically controlled exhaust valve gasket 35 is provided between the electrically controlled exhaust valve spring 34 and the spring seat 36. The spring seat 36 is fixed to the top of the upper housing 7 by screws.

[0036] like Figure 11 As shown, the anti-vacuum valve assembly 40 is equipped with a gasket 37 and an anti-vacuum spring 39. The anti-vacuum spring 39 is pre-compressed to ensure reliable opening of the device. When a negative pressure is formed in the oil tank and the absolute value exceeds the threshold, the anti-vacuum spring 39 is compressed, the valve core is disengaged from the valve seat, and outside air enters the oil tank through the filter element, thereby maintaining the pressure balance inside the oil tank, preventing the oil tank from being sucked down, and preventing the oil tank structure from becoming unstable. Independent sealing elements are provided at the mating surfaces of the housing assembly and valve seat 3, the high-pressure safety valve assembly 28 and valve seat 3, the low-pressure safety valve assembly 8 and valve seat 3, the electrically controlled exhaust valve assembly 33 and valve seat 3, and the anti-vacuum valve assembly 40 and housing assembly, to achieve pressure isolation between the functional chambers and avoid pressure crosstalk.

[0037] The upper housing 7, valve seat 23, ball seat 22, and low-pressure safety valve assembly 8 are all equipped with sealing rings. These sealing rings are used to effectively establish pressure in the back pressure chamber of the low-pressure safety valve assembly 8. Each sealing ring is made of fluororubber, which is oil-resistant and high-temperature resistant.

[0038] like Figure 6 As shown, the electronically controlled valve is a solenoid valve 1, which is configured to open when energized in ground refueling or ground depressurization scenarios to conduct the electronically controlled exhaust valve assembly 33; and to close when de-energized in flight scenarios to prevent accidental depressurization.

[0039] like Figure 13As shown, the solenoid valve assembly 1 includes a socket 101 and a plug 102, a tail accessory 103, and is fixed to a base 104 by screws and washers. The base 104 is fixed to a solenoid valve seat 106 by screws and washers. A spring 105 is provided between the solenoid valve seat 106 and the base 104. A valve seat 107 and an axially sliding valve rod 108 are provided inside the solenoid valve seat 106. A solenoid valve 109 is fitted at the end of the valve rod 108. When the solenoid valve 109 is energized, it generates magnetic force, attracting the valve rod 108 to move axially, compressing the spring 105, and causing the end of the valve rod to disengage from the sealing surface of the valve seat 107, thus opening the exhaust passage. After the power is cut off, the spring 105 returns to its original position, pushing the valve rod 108 to press against the valve seat 107, achieving reliable shut-off.

[0040] Under normal level flight conditions, The device remains vertical. Under the influence of gravity, steel ball 20 presses down on pilot valve assembly 19, opening the pilot hole and connecting the inner cavity of the low-pressure safety valve to the outlet. With no back pressure in the inner cavity, low-pressure safety valve assembly 8 immediately opens fully, allowing for a large flow of air intake to quickly balance the pressure difference between the inside and outside of the oil tank. At this time, both high-pressure safety valve assembly 28 and anti-vacuum valve assembly 40 are closed, maintaining stable oil tank pressure. When the oil tank pressure is too high, the high-pressure safety valve opens to release pressure; when the oil tank pressure is lower than the external air pressure, the anti-vacuum valve opens to replenish air.

[0041] Dive / side flight conditions When the device tilts at an angle exceeding 15°, the steel ball 20 rolls along the inclined surface of the ball seat 22 and disengages from the pilot valve assembly 19. Under the action of the pilot valve spring 18, the pilot valve closes the pressure relief hole and pressure relief channel, creating back pressure within the low-pressure safety valve cavity. This, in turn, increases the opening pressure of the low-pressure safety valve assembly. Because the inner cavity area of ​​the low-pressure safety valve assembly is smaller than the inlet pressure-sensing area, even if the inner cavity pressure is not released, when the oil tank pressure continues to increase to a certain value, this pressure exceeds the opening pressure of the high-pressure safety valve assembly, preventing insufficient oil intake from the oil tank due to posture changes. At this time, the limit baffle restricts the steel ball from rolling away from the valve seat, ensuring that the steel ball can smoothly reset when the posture returns to normal, and the low-pressure safety valve assembly can still open normally to replenish gas to the oil tank.

[0042] Heading up under working conditions The device tilts away from the valve seat, and the steel ball is blocked by the limit baffle, keeping the pilot valve assembly pressed down. The low-pressure safety valve opens normally, avoiding unnecessary pressure increases.

[0043] Ground refueling conditions When the solenoid valve is energized, the pressure relief channel inside the electrically controlled exhaust valve opens, the electrically controlled exhaust valve opens, and excess gas in the fuel tank is discharged. The steel ball 20 is stably centered under the action of gravity, the pilot valve assembly 19 is fully open, and the back pressure of the low-pressure safety valve assembly 8 is reduced to zero. If the aircraft refueling shut-off valve fails after the fuel tank is full, the continuously added fuel can be discharged through the electrically controlled exhaust valve, thereby protecting the fuel tank and preventing overpressure during refueling.

[0044] Ground pressure relief conditions After the aircraft completes its flight mission and lands on the ground, there is still some pressure in the fuel tank. At this time, the solenoid valve is energized, and the electronically controlled exhaust valve assembly opens to release the excess pressure in the fuel tank, thus completing the depressurization operation.

[0045] Under overpressure protection conditions, Under normal operating conditions, the low-pressure safety valve serves as the first level of protection. When the low-pressure valve jams and the pressure difference across the valve is too high, the force generated by the area difference will overcome the spring force and force the low-pressure valve to open, forming the second level of protection. When the low-pressure valve completely fails, the high-pressure safety valve will open to release pressure when the pressure exceeds the set value, forming the third level of protection. The three-level redundancy design can fully ensure system safety.

[0046] like Figure 14 As shown, when the aircraft is cruising horizontally, the steel ball is pressed down by gravity, which opens the pilot pressure relief channel of the low-pressure safety valve assembly. At this time, the opening pressure of the low-pressure safety valve assembly is the set pressure. When the pressure inside the fuel tank is lower than the external air pressure difference and reaches the set pressure of the low-pressure safety valve assembly, the low-pressure safety valve assembly opens to replenish air to the fuel tank and maintain the fuel tank pressure.

[0047] like Figure 15 As shown, when the aircraft is in a dive or side-flight attitude with a tilt angle exceeding 15°, the steel ball rolls along the ball seat slope and disengages from the pilot valve assembly, closing the pressure relief channel. Back pressure is established in the inner cavity of the low-pressure safety valve assembly, at which point its opening pressure increases to meet the fuel tank replenishment requirements under large-attitude flight. If the low-pressure safety valve assembly becomes stuck and cannot open during flight, when the pressure difference between the inside and outside of the fuel tank increases to a pressure greater than the opening pressure of the high-pressure safety valve assembly, the high-pressure safety valve assembly automatically opens to replenish fuel as a redundancy guarantee.

[0048] When the aircraft dives, causing a sudden increase in external air pressure and creating negative pressure inside the fuel tank, the anti-vacuum valve assembly opens under the pressure difference to replenish air into the fuel tank, preventing it from being crushed. After the internal and external pressures are balanced, it automatically resets under the action of the anti-vacuum spring.

[0049] During ground refueling, the control system energizes the solenoid valve, opening the pressure relief channel inside the electronically controlled exhaust valve assembly. Gas in the fuel tank can be discharged through the electronically controlled exhaust valve assembly during refueling. If the refueling shut-off valve fails, fuel continuously injected after the tank is full can overflow through the electronically controlled exhaust valve assembly to prevent overpressure in the fuel tank. After refueling is completed or the aircraft lands, the solenoid valve can be energized to open, releasing excess pressure in the fuel tank through the electronically controlled exhaust valve assembly, thus completing the depressurization operation.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, are all covered within the scope of the claims of the present invention.

Claims

1. A pilot-operated voltage regulating combination device, characterized in that: The device includes a housing assembly and a valve seat (3) fixedly installed inside the housing assembly. The housing assembly has at least one medium inlet and at least one medium outlet. The valve seat (3) is equipped with a low-pressure safety valve assembly (8), a high-pressure safety valve assembly (28), a vacuum valve assembly (40), and an electrically controlled exhaust valve assembly (33). A pilot control module is provided above the low-pressure safety valve assembly (8). The pilot control module includes a valve seat (23) fixed on the valve seat, a rolling trigger movably disposed on the valve seat (23), a pilot valve assembly (19) slidingly engaged with the valve seat (23), and an elastic reset member for providing a reset force to the pilot valve assembly (19). The rolling trigger is configured to generate displacement with the change of device posture, and triggers the opening and closing action of the pilot valve assembly (19) through its own displacement change, thereby adjusting the opening pressure of the low-pressure safety valve assembly (8). The pressure relief channel of the electrically controlled exhaust valve assembly (33) is controllably connected to the electrically controlled valve (1) and is configured to be actively opened or closed according to the working scenario, thereby realizing the functions of ground refueling and exhaust, full oil overflow, and ground pressure relief.

2. The pilot-operated voltage regulating device according to claim 1, characterized in that, The rolling trigger is a steel ball (20). The pilot control module also includes a ball seat (22) fixedly installed on the valve seat (23) and a top cover (21) fixed on the housing assembly. The upper surface of the ball seat (22) is a slope structure, and the steel ball (20) can roll freely along the slope of the ball seat (22). The top cover (21) is provided with a limit structure on the side facing the steel ball. The limit structure is configured to limit the rolling range of the steel ball (20). Only when the tilt angle of the device reaches a preset threshold, the steel ball (20) rolls away from the trigger end of the pilot valve assembly (19), so that the pilot valve assembly (19) closes the pressure relief hole under the action of the elastic reset member, and the inner cavity of the low-pressure safety valve assembly (8) establishes back pressure to increase the opening pressure.

3. The pilot-operated voltage regulating device according to claim 2, characterized in that, The inclined angle of the ball seat (22) is 15°, and the preset threshold is the 15° tilt angle of the device relative to the horizontal position; the elastic reset element is a pilot valve spring (18), which is coaxially installed in the inner cavity of the pilot valve assembly (19); the limiting structure of the top cover (21) is a baffle arranged along the rear side of the steel ball, which is configured to restrict the steel ball (20) to roll only in the front, left and right directions, and prevent the steel ball from moving backward and triggering pressure adjustment when the device is in the head-up posture.

4. The pilot-operated voltage regulating combination device according to claim 1, characterized in that, The inner cavity of the low-pressure safety valve assembly (8) is smaller than its inlet pressure sensing area. It is configured such that even if the pressure relief hole is closed and back pressure is established, when the medium pressure exceeds the opening pressure of the high-pressure safety valve assembly (28), the low-pressure safety valve assembly (8) can still be forced to open by the medium pressure, forming a double-redundant safety structure.

5. The pilot-operated voltage regulating combination device according to claim 1, characterized in that, The low-pressure safety valve assembly (8), the medium inlet side of the electric exhaust valve assembly, and the pipe joint (11) of the medium outlet are all equipped with filter elements to construct a full-path impurity protection structure, which can effectively prevent the pilot hole from being blocked.

6. The pilot-operated voltage regulating combination device according to claim 1, characterized in that, Independent sealing elements are provided on the mating surfaces of the housing assembly and the valve seat (3), the mating surfaces of the high-pressure safety valve assembly (28) and the valve seat (3), the mating surfaces of the low-pressure safety valve assembly (8) and the valve seat (3), the mating surfaces of the electrically controlled exhaust valve assembly (33) and the valve seat (3), and the mating surfaces of the anti-vacuum valve assembly (40) and the housing assembly, so as to realize the pressure isolation of each functional chamber and avoid pressure crosstalk.

7. The pilot-operated voltage regulating device according to claim 1, characterized in that, The housing assembly includes a lower housing (2) and an upper housing (7) fixedly connected by screws (4) and washers (5). The medium inlet is located on the lower housing (2), and the medium outlet is located on the upper housing (7). The low-pressure safety valve assembly (8) and the high-pressure safety valve assembly (28) are both fixedly installed on the upper housing (7), and the vacuum valve assembly (40) is installed on the lower housing (2). The vacuum valve assembly (40) is configured to automatically open to replenish air when the external pressure is higher than the internal pressure. The high-pressure safety valve assembly (28) is configured as a redundant backup of the low-pressure safety valve assembly (8). When the low-pressure safety valve assembly (8) is stuck or the air intake capacity is insufficient, it will automatically open to maintain the internal pressure stability.

8. The pilot-operated voltage regulating combination device according to claim 1, characterized in that, The electrically controlled valve is a solenoid valve (1), which is configured to: open when energized in ground refueling or ground depressurization scenarios to conduct the electrically controlled exhaust valve assembly (33); and close when de-energized in flight scenarios to prevent the device from experiencing unexpected depressurization.

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