A zero-load overload fuel supply device for basic trainer aircraft

Abstract

This invention discloses a zero-load overload fuel supply device for a basic trainer aircraft, belonging to the aircraft fuel system. It includes an inlet pipe, a fuel filter, an aerobatic fuel tank assembly, an auxiliary fuel pump, a check valve, a shut-off valve, a pressure sensor group, a limiter, and a return pipe. Its characteristic is that fuel in the fuel tank enters the aerobatic fuel tank assembly via the inlet pipe and fuel filter, reaching a certain pressure. The fuel is then supplied to the engine via a fuel delivery pendulum and a check valve. Excess fuel vapor in the assembly flows back to the fuel tank under pressure through the limiter, keeping the assembly continuously full of fuel. When the aircraft is briefly under zero-load overload and the fuel tank cannot supply fuel normally, the fuel delivery pendulum, under acceleration, points towards the fuel stored in the assembly. The engine's built-in fuel pump can draw the stored fuel to continue operation. The assembly can also monitor fuel temperature and remaining fuel level and output alarm signals. The fuel supply device is equipped with an auxiliary fuel pump, which can still provide sufficient flow and pressure of fuel when the main pump fails, ensuring normal system operation.

Description

Technical Field

[0001] This invention relates to the field of aircraft fuel systems, specifically a zero-load overload fuel supply device for basic trainer aircraft. Background Technology

[0002] To prevent engine shutdown due to insufficient or interrupted fuel supply, a continuous fuel supply to the engine must be ensured under various flight conditions. The fuel pump can only function properly with an uninterrupted fuel supply. Therefore, aircraft capable of aerobatic flight need to be equipped with zero-load fuel supply systems to guarantee a continuous fuel supply to the fuel pump.

[0003] Typical zero-overload oil supply devices include: mechanical type, position type (high and low pump arrangement, double-sided pump), and accumulator type.

[0004] The mechanical system consists of a negative overload chamber, a counterweight check valve, a fuel tank, and a fuel pump. During normal flight, fuel enters the fuel pump through the upper and lower intake ports of the fuel pump housing. Under zero negative overload conditions, the counterweight check valve closes the lower intake port of the fuel pump housing under the action of gravity, and fuel enters the pump through the upper intake port, thus ensuring that the aircraft can supply fuel to the engine normally under various flight conditions.

[0005] There are two types of positional fuel pumps: high-low pump arrangement and dual-sided pump. The similarity between the two is that fuel pumps are installed at the high and low positions of the fuel tank to ensure that the fuel pumps can stably supply fuel to the engine under different flight conditions. The difference is that the high-low pump arrangement has two independent fuel pumps installed at the top and bottom of the fuel tank, while the dual-sided pump has impellers installed at both the upper and lower ends of the fuel pump, which work simultaneously to supply fuel to the engine.

[0006] The accumulator type uses a bladder to divide the accumulator tank into upper and lower chambers. The upper chamber is the fuel chamber, connected to the fuel supply line, while the lower chamber is the gas chamber, connected to the pressurization system. When the aircraft enters zero- or negative-G flight, the pressure in the fuel supply line drops, and the gas pressure in the gas chamber pushes the bladder, forcing the fuel in the fuel chamber into the fuel supply line to supply the engine. When the aircraft exits zero- or negative-G flight, the fuel supply pump resumes normal operation, filling the accumulator tank with fuel, while the bleed switch releases the gas inside the accumulator tank.

[0007] Mechanical fuel supply systems are complex and heavy, and are rarely used nowadays. Position-type fuel supply systems can supply fuel to the engine under normal flight conditions and under negative overload or inverted flight conditions, but can only guarantee fuel supply for a short time under zero overload conditions. Accumulated fuel supply systems require bleed air from the engine, which reduces engine power and increases the bleed air pipeline, resulting in a complex structure. They are mostly used in fighter jets that emphasize maneuverability. Summary of the Invention

[0008] The purpose of this invention is to provide a zero-load overload fuel supply device for basic trainer aircraft, so as to solve the problems mentioned in the background art, such as the complex structure, high weight, and need to consume engine bleed air of typical zero-load overload fuel supply devices.

[0009] The technical solution of this invention includes: an inlet pipe, a fuel filter, a special fuel tank assembly, an auxiliary fuel pump, a first check valve, a shut-off valve assembly, a pressure sensor group, a first limiter, a second limiter, a second check valve, and a return pipe. The fuel filter includes a fuel filter, a first drain valve, and a first check valve. The special fuel tank assembly includes a second drain valve, a fuel delivery pendulum, a level sensor, a temperature sensor, and a special fuel tank. The fuel delivery pendulum includes a fuel delivery conduit, a clamp, and the pendulum itself, supplying fuel from the tank through the inlet pipe and fuel filter. The fuel enters the aerobatic fuel tank assembly and reaches a certain pressure. The fuel in the assembly is then supplied to the engine through the fuel delivery pendulum and check valve one. Under pressure, the fuel vapor in the assembly flows back to the fuel tank through limiter one and limiter two, and the aerobatic fuel tank assembly is continuously filled. When the aircraft is in a zero-load overload state for a short time and cannot supply fuel normally, the fuel delivery pendulum is affected by the overload and points to the fuel in the assembly to continue supplying fuel to the engine. The fuel supply device is equipped with an auxiliary fuel pump, which can still provide sufficient flow and pressure of fuel when the main pump fails, to ensure the normal operation of the system.

[0010] Furthermore, when the fuel filter becomes clogged, mechanical and electrical alarms can be used to remind maintenance personnel to perform maintenance. When the filter becomes clogged to a certain extent, the increased flow resistance causes the fuel to open the check valve three, thus achieving bypass conduction. During maintenance, the residual fuel in the fuel filter can be drained through the drain valve two, and the filter can be replaced.

[0011] Furthermore, the fuel supply tank outputs a much larger amount of fuel than the engine consumes, ensuring that the special effects fuel tank assembly is continuously filled. This maintains a certain pressure in the fuel within the special effects fuel tank assembly. The fuel in the special effects fuel tank assembly is output in two ways: one way is supplied to the engine via check valve one, shut-off valve, and pressure sensor group; the other way is returned to the fuel supply tank from the top of the special effects fuel tank assembly via the return line, limiter one, limiter two, and so on, ensuring that the assembly is always in a full fuel state.

[0012] Furthermore, the special fuel tank assembly has two return lines on top, each equipped with a limiter. This ensures the return of excess fuel gas within the assembly and maintains a certain pressure within the assembly. At the same time, the two limiters effectively prevent air from being trapped in the assembly due to dirt or debris clogging the limiters, which would cause air bubbles to form in the fuel and affect the fuel supply.

[0013] Furthermore, a check valve is installed on the main pipeline after the two return oil lines of the special effects fuel tank assembly converge, which can prevent fuel in the fuel tank from entering the return oil line.

[0014] Furthermore, when the fuel tank fails to supply fuel normally, the auxiliary fuel pump after the aerobatic fuel tank assembly automatically works, the pressure in the downstream pipeline of the fuel pump increases, and the check valve is closed, so that sufficient flow and pressure of fuel can continue to be output to the engine to ensure that the aircraft can perform normal flight except for aerobatic maneuvers.

[0015] Furthermore, the shut-off valve is installed between the engine and the firewall and is controlled to shut off by the throttle control panel. In the event of a fire in the engine compartment, the pilot can close the valve to effectively prevent the fire from spreading.

[0016] Furthermore, the pressure sensor group is installed on the fuel supply line directly in front of the engine and firewall, which can monitor the fuel inlet pressure in real time and output alarm information through the controller when the fuel pressure is low.

[0017] Furthermore, the main body of the stunt fuel tank is a composite material structure. The second drain valve, the fuel pendulum, the liquid level sensor, and the temperature sensor are installed on the side of the stunt fuel tank and are grounded through a lightning protection plate. During maintenance, fuel can be drained from the assembly through the second drain valve. The main body of the fuel pendulum is a non-rigid structure. One end of the fuel pendulum is installed at the output end of the stunt fuel tank, and the other end is suspended inside the stunt fuel tank and immersed in fuel under the action of gravity. When the liquid level is low, the liquid level sensor can output an alarm message through the controller to limit stunt flight. The temperature sensor monitors the fuel temperature in real time to ensure fuel supply safety.

[0018] Furthermore, the oil delivery conduit at one end of the oil delivery pendulum is installed at the outlet end of the special effects oil tank, while the pendulum at the other end is suspended in the air. The two are connected by a clamp. The oil delivery conduit is a non-rigid structure. When overloaded, the pendulum is affected by acceleration and drives the oil delivery conduit toward the oil stored in the assembly to continue supplying oil to the engine.

[0019] This invention provides a zero-load overload fuel supply device for basic trainer aircraft, which has the following improvements and advantages compared with the prior art:

[0020] Unlike mechanical or positional (high / low pump arrangement, dual-sided pump) fuel supply devices that need to be placed inside the fuel tank, which reduces the size of the fuel tank and structural weight, this invention also differs from accumulator-type devices that require bleed air from the engine, reducing engine power. This invention also integrates an auxiliary fuel pump that can be automatically switched on. When the main fuel pump of the fuel system fails, the auxiliary fuel pump automatically switches on to provide the engine with sufficient flow and pressure of fuel, ensuring normal flight of the aircraft except for aerobatic maneuvers. Attached Figure Description

[0021] The present invention will be further explained below with reference to the accompanying drawings and embodiments:

[0022] Figure 1 This is a structural diagram of the present invention;

[0023] Figure 2 This is a schematic diagram of the present invention;

[0024] Figure 3 The structural diagram of the special fuel tank assembly of the present invention.

[0025] Explanation of reference numerals in the attached diagram: 1. Inlet pipe; 2. Fuel filter; 3. Special effects fuel tank assembly; 4. Auxiliary fuel pump; 5. Check valve one; 6. Shut-off valve assembly; 7. Pressure sensor group; 8a. Limiter one; 8b. Limiter two; 9. Check valve two; 10. Return pipe; 2.1. Fuel filter; 2.2. Drain valve one; 2.3. Check valve three; 3.1. Drain valve two; 3.2. Fuel delivery pendulum; 3.3. Optical level sensor; 3.4. Temperature sensor; 3.5. Special effects fuel tank; 3.2.1. Fuel delivery conduit; 3.2.2. Clamp; 3.2.3. Pendulum; a. Fuel supply tank; b. Controller; c. Engine; d. Throttle control panel. Detailed Implementation

[0026] The following will be combined with the appendix Figures 1 to 3 This invention will be described in detail, and the technical solutions in the embodiments of this invention will be clearly and completely described. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0027] This invention provides an improved zero-load overload fuel supply device for a basic trainer aircraft.

[0028] Example 1, as Figures 1-3 As shown, the assembly includes an inlet pipe 1, a fuel filter 2, a special fuel tank assembly 3, an auxiliary fuel pump 4, a check valve 1 5, a shut-off valve assembly 6, a pressure sensor group 7, a limiter 1 8a, a limiter 2 8b, a check valve 2 9, and a return pipe 10. The fuel filter 2 includes a fuel filter 2.1, a drain valve 1 2.2, and a check valve 3 2.3. The special fuel tank assembly 3 includes a drain valve 2 3.1, a fuel delivery pendulum 3.2, a level sensor 3.3, a temperature sensor 3.4, and a special fuel tank 3.5. The fuel delivery pendulum 3.2 includes a fuel delivery conduit 3.2.1 and a clamp 3.2.2. The fuel in fuel tank a enters the special effects fuel tank assembly 3 through fuel inlet pipe 1 and fuel filter 2, and reaches a certain pressure. The fuel in the assembly is then supplied to engine c through fuel delivery pendulum 3.2 and check valve 5. Under pressure, the fuel vapor in the assembly flows back to fuel tank a through limiter 8a and limiter 8b. When the aircraft is in a zero-overload state for a short time and cannot supply fuel normally, the fuel delivery pendulum 3.2 is affected by the overload and points to the fuel in the assembly to continue supplying fuel to the engine. The fuel supply device is equipped with an auxiliary fuel pump, which can still provide sufficient flow and pressure of fuel when the main pump fails, to ensure the normal operation of the system.

[0029] Example 2, as Figures 1-3 As shown, when fuel filter 2 becomes clogged, it can trigger mechanical and electrical alarms. The flow resistance of filter 2.1 increases, and fuel overcomes the opening pressure of check valve 2.3, achieving bypass conduction. Fuel filter 2 can drain residual fuel through drain valve 2.2. Filter 2.1 is replaced, and the fuel output from fuel tank a is much greater than the fuel consumption of engine c. The special fuel tank assembly 3 is continuously filled, maintaining a certain fuel pressure within the assembly. Fuel 1 is supplied from the assembly through check valve 5, shut-off valve 6, and pressure sensor group 7. The oil flows from the return line at the top of the special effects oil tank assembly 3, through limiter 1 8a and limiter 2 8b, back to the supply tank a, ensuring that the special effects oil tank assembly 3 is always full of oil. There are two return lines at the top of the special effects oil tank assembly 3, and each return line is equipped with a limiter. This ensures that excess oil and gas in the assembly can flow back, and also ensures that there is a certain pressure in the assembly. At the same time, the two limiters can effectively prevent air from being unable to escape from the special effects oil tank assembly 3 due to dirt clogging the limiters, which would affect the oil supply effect.

[0030] Example 3, as Figures 1-3 As shown, a check valve 2 9 is installed on the return line of the special effects fuel tank assembly 3 to prevent fuel from the supply tank a from entering the return line. When the supply tank a cannot supply fuel normally, the auxiliary fuel pump 4 after the special effects fuel tank assembly 3 works, the pressure in the downstream line of the fuel pump increases, and the check valve 1 5 is closed. It can still output enough flow and pressure of fuel to the engine c. The shut-off valve 6 is installed between the engine and the firewall and is controlled by the throttle control panel d to close the valve. In the event of a fire in the engine compartment, the pilot can close the valve to prevent the fire from spreading. A pressure sensor group 7 is installed on the fuel supply line directly in front of the engine and the firewall to monitor the fuel inlet pressure. When the fuel pressure is low, the controller b outputs an alarm message.

[0031] Example 4, as Figures 1-3As shown, the main body of the stunt fuel tank 3.5 is a composite material structure. The drain valve 3.1, fuel transfer pendulum 3.2, level sensor 3.3, and temperature sensor 3.4 are installed on the side of the stunt fuel tank 3.5, connected to the ground via a lightning protection plate. Fuel can be drained from the assembly through the drain valve 3.1 for maintenance and repair. The fuel transfer pendulum 3.2 is a non-rigid structure; one end of the pendulum 3.2 is installed at the output end of the stunt fuel tank 3.5, and the other end is suspended inside the tank. When the fuel level is low, the level sensor 3.3 can output an alarm message through controller b, limiting flight. The temperature sensor... Sensor 3.4 monitors fuel temperature to ensure fuel supply safety. The fuel supply pendulum 3.2 consists of fuel supply pipe 3.2.1, clamp 3.2.2, and pendulum 3.2.3. One end of the fuel supply pipe 3.2.1 is installed at the outlet of the special fuel tank 3.5, and the other end is connected to the pendulum 3.2.3 through clamp 3.2.2. The fuel supply pipe 3.2.1 is a non-rigid structure. The pendulum 3.2.3 hangs below the center line of the fuel tank due to gravity. When overloaded, the pendulum 3.2.3 drives the fuel supply pipe 3.2.1 towards the fuel in the assembly under the action of acceleration to continue to draw fuel and ensure that the engine can work normally for a short time under zero-load overload.

[0032] Working principle: Fuel in fuel tank a enters the special fuel tank assembly 3 through fuel inlet pipe 1 and fuel filter 2, and reaches a certain pressure. The fuel in the assembly is then supplied to engine c through fuel delivery pendulum 3.2 and check valve 5. Under pressure, the fuel vapor in the assembly flows back to fuel tank a through limiter 8a and limiter 8b. When the aircraft is in a zero-load overload state for a short time and cannot supply fuel normally, the fuel delivery pendulum 3.2 is affected by the overload and points to the fuel in the assembly to continue supplying fuel to the engine. The fuel supply device is equipped with an auxiliary fuel pump, which can still provide sufficient flow and pressure of fuel when the main pump fails, ensuring the normal operation of the system.

[0033] When fuel filter 2 becomes clogged, mechanical and electrical alarms are triggered. The flow resistance of filter 2.1 increases, allowing fuel to overcome the opening pressure of check valve 2.3, thus bypassing the flow. The fuel output from fuel tank a is significantly greater than the fuel consumption of engine c, ensuring the special fuel tank assembly 3 is continuously filled. This maintains a certain fuel pressure within the assembly. Fuel is supplied to engine c via two routes: one from the assembly through check valve 5, shut-off valve 6, and pressure sensor group 7; and another from the return line at the top of the special fuel tank assembly 3, through limiter 8a, and limiter 8b, returning to fuel tank a. This ensures the special fuel tank assembly 3 remains full. The top of the special fuel tank assembly 3 has two return lines, each equipped with a limiter. This ensures the return of excess fuel vapors and maintains a certain pressure within the assembly. Simultaneously, the two limiters effectively prevent air from escaping the special fuel tank assembly 3 due to dirt or debris clogging the limiters, thus avoiding interference with fuel supply.

[0034] When fuel tank a fails to supply fuel normally, the auxiliary fuel pump 4 after the special effects fuel tank assembly 3 works, the pressure in the downstream pipeline of the fuel pump increases, and the check valve 5 is closed. It can still output enough flow and pressure of fuel to engine c. The shut-off valve 6 is installed between the engine and the firewall and is controlled by the throttle control panel d to close the valve. In the event of a fire in the engine compartment, the pilot can close the valve to prevent the fire from spreading. A pressure sensor group 7 is installed on the fuel supply line directly in front of the engine and the firewall to monitor the fuel inlet pressure. When the fuel pressure is low, the controller b outputs an alarm message.

[0035] Meanwhile, the level sensor 3.3 can output an alarm message through the controller b when the fuel level is low, limiting flight. The temperature sensor 3.4 monitors the fuel temperature to ensure fuel supply safety. The fuel pendulum 3.2 consists of the fuel delivery pipe 3.2.1, the clamp 3.2.2, and the pendulum 3.2.3. One end of the fuel delivery pipe 3.2.1 is installed at the outlet of the special effects fuel tank 3.5, and the other end is connected to the pendulum 3.2.3 through the clamp 3.2.2. The fuel delivery pipe 3.2.1 is a non-rigid structure. The pendulum 3.2.3 hangs below the center line of the fuel tank due to gravity. When overloaded, the pendulum 3.2.3 drives the fuel delivery pipe 3.2.1 towards the fuel in the assembly under the action of acceleration to continue to draw fuel and ensure that the engine can work normally for a short time under zero-load overload.

[0036] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A zero-load overload fuel supply device for a basic trainer aircraft, characterized in that: The assembly includes an inlet pipe (1), a fuel filter (2), a special effects fuel tank assembly (3), an auxiliary fuel pump (4), a check valve (5), a shut-off valve (6), a pressure sensor group (7), a limiter (8a), a limiter (8b), a check valve (9), a return pipe (10), and a fuel supply tank (a). Fuel in the fuel supply tank (a) enters the special effects fuel tank assembly (3) via the inlet pipe (1) and the fuel filter (2), reaching a certain pressure. The fuel in the assembly then... The fuel supply pendulum (3.2) and check valve 1 (5) supply fuel to the engine (c). Under pressure, the oil and gas in the assembly flow back to the fuel tank (a) through limiter 1 (8a) and limiter 2 (8b). When the aircraft is in a state of zero negative overload for a short time and cannot supply fuel normally, the fuel supply pendulum (3.2) is affected by the overload and points to the oil in the assembly to continue supplying fuel to the engine. The fuel supply device is equipped with an auxiliary oil pump. When the main pump fails, it can still provide enough flow and pressure of fuel to ensure the normal operation of the system. The fuel supply tank (a) outputs much more fuel than the engine (c) consumes, so the special effects fuel tank assembly (3) is continuously filled, keeping the fuel in the assembly at a certain pressure. One fuel line runs from the assembly through check valve (5), shut-off valve (6), and pressure sensor group (7) to the engine (c), while another line runs from the return line at the top of the special effects fuel tank assembly (3), limiter one (8a), and limiter two (8b) back to the fuel supply tank (a), ensuring that the special effects fuel tank assembly (3) is always full of fuel. When the fuel tank (a) fails to supply fuel normally, the auxiliary fuel pump (4) after the special fuel tank assembly (3) works, the pressure in the downstream pipeline of the fuel pump increases, and the check valve (5) is closed, so that sufficient flow and pressure of fuel can still be output to the engine (c).

2. The zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: When the fuel filter (2) becomes clogged, it can be alerted by mechanical and electrical means, and bypass can be achieved through check valve three (2.3). It can also drain residual oil through drain valve one (2.2) and replace filter (2.1).

3. The zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: The stunt fuel tank assembly (3) has two return oil lines on the top. Each return oil line is equipped with a limiter, which ensures that excess oil and gas in the assembly can flow back and that there is a certain pressure in the assembly. At the same time, the two limiters can effectively prevent the air in the stunt fuel tank assembly (3) from being unable to be discharged due to dirt clogging the limiters, thus affecting the fuel supply effect.

4. A zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: The special effects fuel tank assembly (3) has a check valve (9) installed on the return line to prevent fuel from the fuel tank (a) from entering the return line.

5. A zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: The shut-off valve (6) is installed between the engine and the firewall and is controlled to shut off by the throttle control panel (d). In the event of a fire in the engine compartment, the pilot can close the valve to prevent the fire from spreading.

6. A zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: The pressure sensor group (7) is installed on the fuel supply line directly in front of the engine and firewall to monitor the fuel inlet pressure. When the fuel pressure is low, the controller (b) outputs an alarm message.

7. A zero-load overload fuel supply device for a basic trainer aircraft according to claim 1, characterized in that: The main body of the stunt fuel tank (3.5) is a composite material structure. The second drain valve (3.1), the fuel pendulum (3.2), the liquid level sensor (3.3), and the temperature sensor (3.4) are installed on the side of the stunt fuel tank (3.5). They are grounded through the lightning protection plate. The fuel can be drained from the assembly through the second drain valve (3.1) for maintenance and repair. The main body of the fuel pendulum (3.2) is a non-rigid structure. One end of the fuel pendulum (3.2) is installed at the output end of the stunt fuel tank (3.5), and the other end of the fuel pendulum (3.2) is suspended inside the stunt fuel tank (3.5). When the liquid level sensor (3.3) is low, it can output an alarm message through the controller (b) to restrict flight. The temperature sensor (3.4) monitors the fuel temperature to ensure fuel supply safety.

8. A zero-load overload fuel supply device for a basic trainer aircraft according to claim 7, characterized in that: The oil delivery pipe (3.2.1) at one end of the oil delivery pendulum (3.2) is installed at the outlet end of the special fuel tank (3.5), and the pendulum (3.2.3) at the other end of the oil delivery pendulum (3.2) is suspended in the air. The two are connected by a clamp (3.2.2). The oil delivery pipe (3.2.1) is a non-rigid structure. When overloaded, the pendulum (3.2.3) is affected by acceleration and drives the oil delivery pipe (3.2.1) toward the oil stored in the assembly to continue supplying oil to the engine.

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