An engine fuel control system automatic air release and ejector oil return integrated device and method

Abstract

The application discloses an automatic air release and injection oil return integrated device and method of an engine fuel control system and relates to the technical field of fuel regulation.The device comprises a differential pressure valve, a minimum pressure parking valve, a steel ball, a spring and an air release valve.The application designs an integrated system structure capable of realizing automatic air release before engine starting and injection oil return after engine starting.The application improves the previous mode of realizing the above-mentioned two functions by setting a separate air release valve and a separate injection oil return valve, guarantees the functions, reduces the number of parts of the engine metering device, makes the fuel system structure more compact, saves materials, realizes automatic switching of air release and injection oil return, saves manual air release time, improves the reliability of the fuel system and the working efficiency of the product.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fuel regulation, and particularly relates to an automatic air release and injection oil return integrated device and method of an engine fuel control system. BACKGROUND

[0002] In an aero-engine fuel control system, starting air release and injection oil return are important functions. The traditional engine pre-start exhaust work is usually responsible by a single air release valve, which is in an automatic or manual form. The injection oil return function is usually composed of a parking valve and a differential pressure valve, which returns the excess fuel provided by the fuel supply system to the aircraft fuel tank after the engine metering, ensures the import filling of the fuel supply system while taking away the excess heat, and reduces the temperature rise of the engine metering device. The above two functions are generally composed of four to five structures, which increases the complexity of the engine metering device and reduces its reliability. To solve this problem, the patent proposes an integrated method of engine pre-start air release and post-supply injection oil return. SUMMARY

[0003] Based on the above background, to meet the design requirements of lightweight, miniaturization and automation of the aero-engine, an integrated system structure is designed, which can realize automatic air release before engine starting and injection oil return after engine starting.

[0004] Therefore, according to an aspect of the embodiments of the present application, an engine fuel control system automatic bleeding and injection back oil integrated device is provided, comprising: a pressure difference valve 1, a minimum pressure parking valve 2, a steel ball 3, a spring 4, a bleeding valve 5; wherein the steel ball 3 is installed in the spring cavity of the bleeding valve 5 through the spring 4, forming an automatic bleeding device, the diameter of the steel ball 3 matches the inner diameter of the spring cavity, the steel ball 3 can block the spring cavity and move axially therein, the pressure difference valve 1 functions to ensure that the pressure difference before and after the fuel pump regulator metering valve is basically constant, the A port of the pressure difference valve 1 is an oil inlet port, the fuel after the gear pump flows into the pressure difference valve through the A port of the pressure difference valve 1; the B port of the pressure difference valve 1 is a back oil port, part of the fuel after the gear pump returns to the front of the gear pump through the B port of the pressure difference valve 1, the C port of the pressure difference valve 1 is an oil outlet port; the minimum pressure parking valve 2 functions to provide a certain pressure for the fuel inside the fuel pump regulator, the A port of the minimum pressure parking valve 2 is an oil inlet port, the D port of the minimum pressure parking valve 2 is an oil outlet port, the fuel after the metering valve flows into the minimum pressure parking valve through the A port of the minimum pressure parking valve, and then flows out to the engine combustion chamber through the D port of the minimum pressure parking valve after the valve core is moved; the B port of the minimum pressure parking valve 2 is an oil inlet port, the C port of the minimum pressure parking valve 2 is an oil outlet port, when the engine starts, the minimum pressure parking valve 2 is opened, the B port and the C port are only connected through the valve core annular cavity, the injection fuel enters the minimum pressure parking valve 2 through the B port of the minimum pressure parking valve 2, and then flows out to the bleeding valve through the valve core annular cavity from the C port of the minimum pressure parking valve 2; the bleeding valve 5 is arranged on the passage before the gear pump and the injection outlet, the A port of the bleeding valve 5 is a low-pressure fuel inlet port, the B port of the bleeding valve 5 is an injection fuel inlet port, and the C port of the bleeding valve 5 is an injection fuel outlet port, when the minimum pressure parking valve 2 is not opened, the B port and the C port of the minimum pressure parking valve 2 are not connected, the injection passage is in a closed state, the spring cavity of the bleeding valve 5 has no pressure, and the low-pressure fuel before the gear pump enters the flow passage through the A port of the bleeding valve 5 to return to the oil tank, thereby bleeding the system.

[0005] Optionally, the automatic bleeding device is installed at the uppermost part of the fuel pump regulator.

[0006] According to another aspect of the embodiments of the present application, an engine fuel control system automatic bleeding and injection back oil integrated method is also provided, using any of the devices, comprising: when the engine starts, the minimum pressure parking valve is opened, the B port and the C port of the minimum pressure parking valve are connected, the injection passage is established, the injection fuel enters through the B port of the bleeding valve, passes through the spring cavity of the bleeding valve, and flows out to the aircraft oil tank from the C port, since the injection fuel is high-pressure fuel, the injection fuel together with the spring pushes the steel ball to move to the left, closes the low-pressure fuel from the A port, and realizes the automatic closing of the bleeding valve.

[0007] Optionally, the minimum pressure parking valve 2 is opened when the pressure after the metering reaches a specified value.

[0008] Optionally, before the fuel pump regulator is started, the post-pump fuel and the post-metering fuel are both low-pressure fuel, the low-pressure return fuel communicates with the air release valve 5A, the steel ball 3 overcomes the spring force of the spring 4, and the gas is discharged through the air release valve 5C.

[0009] Optionally, after the fuel pump regulator is started, the post-pump fuel and the post-metering fuel are both high-pressure fuel, the post-metering fuel communicates with the engine combustion chamber through the minimum pressure parking valve 2, is divided into two paths, one path returns to the front of the gear pump through the pressure difference valve 1B, and the other path enters the low-pressure cavity of the minimum pressure parking valve 2 through the pressure difference valve 1C, and then flows into the air release valve 5B through the minimum pressure parking valve 2C. At this time, the spring cavity of the air release valve 5 is high pressure, the steel ball 3 is pushed to move outward and close to the end surface of the air release valve 5, and the low-pressure fuel cannot flow into the air release valve 5C, thereby ending the automatic air release stage and realizing automatic air release and automatic switching to the injection return function.

[0010] Optionally, the post-pump fuel returns to the aircraft fuel tank through the pressure difference valve 1, the minimum pressure parking valve 2 and the spring cavity of the air release valve 5.

[0011] Optionally, when the engine is not started, since the minimum pressure parking valve is not opened, the B port and the C port of the minimum pressure parking valve are not communicated, the injection path is in the off state, the spring cavity of the air release valve is basically without pressure, and the low-pressure fuel before the gear pump overcomes the spring force and enters the flow path through the air release valve A port to return to the tank, thereby releasing the system. When the engine is started, the minimum pressure parking valve is opened, the B port and the C port of the minimum pressure parking valve are communicated, the injection path is established, the injection fuel enters through the air release valve B port, passes through the spring cavity of the air release valve and flows out from the C port to the aircraft fuel tank. Since the injection fuel is high-pressure fuel, the steel ball is pushed to move to the left together with the spring, the low-pressure fuel from the A port is closed, the automatic closing of the air release valve is realized, and the air release valve is realized.

[0012] The application adopts a method for realizing engine starting air release and injection return by cooperation of a spring, a steel ball, a pressure difference valve and a parking valve, and the innovation point lies in that:

[0013] 1. The method improves the previous way of realizing the two functions by setting a separate air release valve and a separate injection return valve, guarantees the functions, reduces the number of parts of the engine metering device, makes the fuel system structure more compact, and saves materials.

[0014] 2. The air release and the injection return can realize automatic switching function, saves the manual air release time, improves the reliability of the fuel system and the working efficiency of the product. DETAILED DESCRIPTION

[0015] Figure 1Structure diagram of an automatic air release and oil injection integrated device of an engine fuel control system according to the present application.

[0016] Legend of reference signs:

[0017] 1 - pressure difference valve, 2 - minimum pressure parking valve, 3 - steel ball, 4 - spring, 5 - air release valve. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be apparently and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present application.

[0019] According to an aspect of the embodiments of the present application, an automatic air release and oil injection integrated device of an engine fuel control system is provided, which comprises a pressure difference valve 1, a minimum pressure parking valve 2, a steel ball 3, a spring 4, and an air release valve 5. The steel ball 3 is installed in a spring cavity of the air release valve 5 by the spring 4 to form an automatic air release device. The diameter of the steel ball 3 matches the inner diameter of the spring cavity, and the steel ball 3 can block the spring cavity and move axially in the spring cavity. The pressure difference valve 1 functions to ensure that the pressure difference before and after a metering valve of a fuel pump regulator is basically constant. The A port of the pressure difference valve 1 is an oil inlet port, and the fuel after the gear pump flows into the pressure difference valve through the A port. The B port of the pressure difference valve 1 is an oil return port, and part of the fuel after the gear pump returns to the front of the gear pump through the B port. The C port of the pressure difference valve 1 is an oil outlet port. The minimum pressure parking valve 2 functions to provide a certain pressure for the fuel inside the fuel pump regulator. The A port of the minimum pressure parking valve 2 is an oil inlet port, and the D port of the minimum pressure parking valve 2 is an oil outlet port. The fuel after the metering valve flows into the minimum pressure parking valve through the A port, pushes the valve core to move, and then flows out to the engine combustion chamber through the D port. The B port of the minimum pressure parking valve 2 is an oil inlet port, and the C port of the minimum pressure parking valve 2 is an oil outlet port. When the engine starts, the minimum pressure parking valve 2 is opened, the B port and the C port are only connected through the annular cavity of the valve core, the injection fuel enters the minimum pressure parking valve 2 through the B port, passes through the annular cavity of the valve core, and then flows out to the air release valve through the C port. The air release valve 5 is arranged on the passage before the gear pump and the injection outlet. The A port of the air release valve 5 is a low-pressure fuel inlet port, the B port of the air release valve 5 is an injection fuel inlet port, and the C port of the air release valve 5 is an injection fuel outlet port. When the minimum pressure parking valve 2 is not opened, the B port and the C port of the minimum pressure parking valve 2 are not connected, the injection passage is in a closed state, the spring cavity of the air release valve 5 has no pressure, and the low-pressure fuel before the gear pump enters the flow passage through the A port of the air release valve 5 to return to the oil tank to release the system.

[0020] Further, the automatic air release device is installed at the uppermost part of the fuel pump regulator.

[0021] According to another aspect of the embodiments of the present application, an engine fuel control system automatic air release and ejection oil return integrated method is also provided, using any of the devices, comprising: when the engine starts, the minimum pressure parking valve opens, the B port and the C port of the minimum pressure parking valve are communicated, the ejection passage is established, the ejection fuel enters through the B port of the air release valve, passes through the air release valve spring cavity, and flows out from the C port to the aircraft fuel tank. Since the ejection fuel is high-pressure fuel, the ejection fuel together with the spring will push the steel ball to move to the left, close the low-pressure fuel from the A port, and achieve automatic closing of the air release valve.

[0022] Further, the minimum pressure parking valve opens when the metered post-pressure reaches a specified value.

[0023] Further, before the fuel pump regulator starts, the post-pump fuel and the metered post-fuel are both low-pressure fuel, the low-pressure oil return communicates the A port of the air release valve 5, the steel ball 3 overcomes the spring force of the spring 4, and the gas is discharged through the C port of the air release valve 5.

[0024] Further, after the fuel pump regulator starts, the post-pump fuel and the metered post-fuel are both high-pressure fuel, the metered post-fuel communicates the engine combustion chamber through the minimum pressure parking valve 2, and is divided into two paths, one path returns to the front of the gear pump through the B port of the pressure difference valve 1, and the other path enters the low-pressure cavity of the minimum pressure parking valve 2 through the C port of the pressure difference valve 1, and then flows into the B port of the air release valve 5 through the C port of the minimum pressure parking valve 2. At this time, the spring cavity of the air release valve 5 is high pressure, which pushes the steel ball 3 to move outward and close to the end surface of the air release valve 5, and the low-pressure fuel cannot flow into the C port of the air release valve 5, ending the automatic air release stage, thereby realizing automatic air release and automatic conversion to ejection oil return function.

[0025] Further, the post-pump fuel returns to the aircraft fuel tank through the pressure difference valve 1, the minimum pressure parking valve 2, and the spring cavity of the air release valve 5.

[0026] Further, when the engine is not started, since the minimum pressure parking valve is not opened, the B port and the C port of the minimum pressure parking valve are not communicated, the ejection passage is in a closed state, the air release valve spring cavity is basically under no pressure, and the low-pressure fuel before the gear pump overcomes the spring force to enter the flow passage through the A port of the air release valve and return to the fuel tank, thereby releasing the system; when the engine starts, the minimum pressure parking valve opens, the B port and the C port of the minimum pressure parking valve are communicated, the ejection passage is established, the ejection fuel enters through the B port of the air release valve, passes through the air release valve spring cavity, and flows out from the C port to the aircraft fuel tank. Since the ejection fuel is high-pressure fuel, the ejection fuel together with the spring will push the steel ball to move to the left, close the low-pressure fuel from the A port, and achieve automatic closing of the air release valve.

[0027] Example

[0028] like Figure 1 As shown, the integrated device of the present invention consists of a differential pressure valve 1, a minimum pressure stop valve 2, a steel ball 3, a spring 4, and a vent valve 5. The steel ball 3 and spring 4 are installed in the vent valve 5, forming an automatic venting device, which is placed at the top of the fuel pump regulator for easy gas discharge. Before the fuel pump regulator is started, since the high-pressure pump is not started, both the fuel after the pump and the fuel after metering are low-pressure fuel. The low-pressure return fuel enters through the vent valve 5A port, pushing the steel ball 3 to overcome the spring force of the spring 4, and the gas is discharged through the vent valve 5C port.

[0029] After the fuel pump regulator starts, both the post-pump fuel and the post-metered fuel are high-pressure fuel. The post-metered fuel enters the engine combustion chamber through the minimum pressure stop valve. The post-pump fuel first meets the engine's metered fuel needs, and the excess fuel is divided into two paths, one of which passes through the differential pressure valve 1B. The fuel returned to the gear pump is used to fill the gear pump inlet. Another path enters the low-pressure chamber of the minimum pressure stop valve 2 through the differential pressure valve 1C, and then flows into the vent valve 5B through the minimum pressure stop valve 2D. At this time, the spring chamber of the vent valve 5 is under high pressure, pushing the steel ball 3 to the left and close to the end face of the vent valve 5. The low-pressure fuel cannot flow into the vent valve 5C, ending the automatic venting stage. This realizes the automatic venting and automatic conversion to ejector fuel return function. The fuel after pumping returns to the aircraft fuel tank through the differential pressure valve 1, the minimum pressure stop valve 2, and the spring chamber of the vent valve 5. Because some of the fuel after pumping flows out of the fuel pump regulator, it does not cause a temperature rise in the fuel pump regulator, thus reducing the temperature rise. At the same time, the ejector fuel can reverse heat the fuel in the fuel tank, reducing the probability of fuel icing during high-altitude flight.

[0030] The differential pressure valve is designed to maintain a relatively constant pressure difference across the fuel pump regulator metering valve. It has three oil passages: Port A is the inlet, through which fuel from the gear pump flows into the differential pressure valve; Port B is the return port, through which some of the pumped fuel returns to the front of the gear pump; and Port C is the outlet, through which some of the pumped fuel is converted into ejector return fuel during engine operation and flows into the aircraft fuel tank via the minimum pressure stop valve and vent valve.

[0031] The minimum pressure parking valve functions to provide a certain pressure for fuel in the fuel pump regulator to ensure normal operation of the system. The minimum pressure parking valve opens when the pressure after metering reaches a specified value. Four oil passage holes are provided, A is an oil inlet hole, D is an oil outlet hole, fuel after the metering valve flows into the minimum pressure parking valve through A, pushes the valve core to move and then flows out through D to the engine combustion chamber; B is an oil inlet hole, C is an oil outlet hole, when the engine starts, the minimum pressure parking valve opens, B and C are connected through the valve core annular cavity, injection fuel enters the minimum pressure parking valve through B, and then flows out through C to the air release valve.

[0032] The air release valve is arranged on the passage between the gear pump and the injection outlet, and three oil passage holes are provided, A is a low pressure fuel inlet hole, B is an injection fuel inlet hole, and C is an injection fuel outlet hole. When the aircraft / vehicle platform booster pump starts and the engine does not start, the minimum pressure parking valve does not open, B and C of the minimum pressure parking valve are not connected, the injection passage is in a closed state, the spring cavity of the air release valve is basically under no pressure, and the low pressure fuel before the gear pump overcomes the spring force to enter the flow passage through the air release valve A and return to the oil tank to release the system. When the engine starts, the minimum pressure parking valve opens, B and C of the minimum pressure parking valve are connected, the injection passage is established, injection fuel enters through the air release valve B, passes through the spring cavity of the air release valve, and flows out from C to the aircraft oil tank. Since the injection fuel is high pressure fuel, the injection fuel together with the spring pushes the steel ball to move to the left, closes the low pressure fuel from A, and realizes automatic closing of the air release valve.

[0033] The above is only a specific embodiment of the present application, which is described in detail, and the part not described is a conventional technology. However, the protection scope of the present application is not limited to this, any changes or replacements within the technical range disclosed by the present application can be easily thought by those skilled in the art, which should be covered in the protection scope of the present application. The protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An integrated device for automatic bleed-out and ejector fuel return in an engine fuel control system, characterized in that, include: The system consists of a differential pressure valve (1), a minimum pressure stop valve (2), a steel ball (3), a spring (4), and a vent valve (5). The steel ball (3) is installed in the spring cavity of the vent valve (5) via the spring (4), forming an automatic vent device. The diameter of the steel ball (3) matches the inner diameter of the spring cavity. The steel ball (3) can block the spring cavity and move axially within it. The differential pressure valve (1) ensures that the pressure difference before and after the fuel pump regulator metering valve remains basically constant. Port A of the differential pressure valve (1) is the fuel inlet. The gear pump then... Oil flows into the differential pressure valve (1) through port A; port B of the differential pressure valve (1) is the return port, and some of the fuel after pumping returns to the front of the gear pump through port B of the differential pressure valve (1), and port C of the differential pressure valve (1) is the outlet port; the function of the minimum pressure stop valve (2) is to ensure that the fuel inside the fuel pump regulator has a certain pressure, port A of the minimum pressure stop valve (2) is the inlet port, and port D of the minimum pressure stop valve (2) is the outlet port. After metering, the fuel flows into the minimum pressure stop valve (2) through port A of the minimum pressure stop valve (2), pushing... After the moving valve core moves, it flows out through the D port of the minimum pressure stop valve (2) to the engine combustion chamber; the B port of the minimum pressure stop valve (2) is the oil inlet, and the C port of the minimum pressure stop valve (2) is the oil outlet. When the engine starts, the minimum pressure stop valve (2) opens, and the B port and the C port are connected only through the valve core annular cavity. The ejected fuel enters the minimum pressure stop valve (2) through the B port of the minimum pressure stop valve (2), flows out through the valve core annular cavity, and flows out through the C port of the minimum pressure stop valve (2) to the vent valve (5). The vent valve (5) is set in the passage between the gear pump and the ejector outlet. Port A is the low-pressure fuel inlet, port B is the ejector fuel inlet, and port C is the ejector fuel outlet. When the minimum pressure stop valve (2) is not open, ports B and C of the minimum pressure stop valve (2) are not connected, the ejector passage is closed, the spring chamber of the vent valve (5) is pressureless, and the low-pressure fuel in front of the gear pump overcomes the spring force and enters the flow passage through port A of the vent valve (5) to return to the fuel tank, thus venting the system.

2. The apparatus according to claim 1, characterized in that, The automatic bleed device is installed at the top of the fuel pump regulator.

3. A method for integrating automatic bleed-out and ejector fuel return in an engine fuel control system, characterized in that, The automatic venting and ejector return integrated device for an engine fuel control system as described in any one of claims 1-2 includes: when the engine is started, the minimum pressure stop valve (2) is opened, the B port of the minimum pressure stop valve (2) is connected to the C port, the ejector passage is established, the ejector fuel enters through the B port of the venting valve (5), passes through the spring cavity of the venting valve (5), and flows out from the C port to the aircraft fuel tank. Since the ejector fuel is high-pressure fuel, the ejector fuel together with the spring will push the steel ball to move outward, closing the low-pressure fuel from the A port, thereby realizing the automatic closing of the venting valve (5).

4. The method according to claim 3, characterized in that, The minimum pressure stop valve (2) opens when the pressure reaches the specified value after metering.

5. The method according to claim 3, characterized in that, Before the fuel pump regulator is started, both the fuel after the pump and the fuel after metering are low-pressure fuel. The low-pressure return oil is connected to the vent valve (5) port A. The steel ball (3) overcomes the spring force of the spring (4), and the gas is discharged through the vent valve (5) port C.

6. The method according to claim 3, characterized in that, After the fuel pump regulator is started, both the fuel after pumping and the fuel after metering are high-pressure fuel. The fuel after metering is connected to the engine combustion chamber through the minimum pressure stop valve (2). The fuel after pumping is divided into two paths. One path returns to the front of the gear pump through the B port of the differential pressure valve (1), and the other path enters the annular cavity of the valve core of the minimum pressure stop valve (2) through the C port of the differential pressure valve (1). Then it flows into the B port of the vent valve (5) through the C port of the minimum pressure stop valve (2). At this time, the spring cavity of the vent valve (5) is under high pressure, which pushes the steel ball (3) to move outward close to the end face of the vent valve (5). The low-pressure fuel cannot flow into the C port of the vent valve (5), and the automatic venting stage ends, thereby realizing the automatic venting and automatic conversion to the ejector return function.

7. The method according to claim 3, characterized in that, After pumping, the fuel returns to the aircraft fuel tank through the spring chamber of the differential pressure valve (1), the minimum pressure stop valve (2), and the vent valve (5).

8. The method according to claim 3, characterized in that, When the engine is not started, the minimum pressure stop valve is not open, and ports B and C of the minimum pressure stop valve are not connected, so the ejector passage is closed. The bleed valve spring chamber is essentially pressureless. Low-pressure fuel before the gear pump overcomes the spring force and enters the flow path through port A of the bleed valve to return to the fuel tank, bleeding the system. When the engine starts, the minimum pressure stop valve opens, and ports B and C of the minimum pressure stop valve are connected, establishing the ejector passage. Ejector fuel enters through port B of the bleed valve, passes through the bleed valve spring chamber, and flows out through port C to the aircraft fuel tank. Since the ejector fuel is high-pressure fuel, the ejector fuel, along with the spring, pushes the steel ball outward, closing the low-pressure fuel from port A, thus achieving automatic closure of the bleed valve.

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