A fuel distributor with oil and air draining functions

Abstract

The present invention provides a fuel distributor with oil and gas discharge functions, comprising a main housing and a one-way valve. The main housing is provided with a transverse passage and a longitudinal passage, which are cross-connected. One end of the transverse passage is an oil inlet, and the other end is an auxiliary oil passage, which is provided with a one-way valve. One end of the longitudinal passage is a main oil passage, and the other end is an oil discharge passage. When the auxiliary power unit combustion chamber adopts dual oil supply, the present invention provides fuel at a certain pressure and flow rate to the main and auxiliary oil passages as required. This not only meets the dual oil supply requirements of the auxiliary power unit combustion chamber, but also enables the discharge of oil seals and the release of gas inside the main body accessories when the aircraft auxiliary power unit is unsealed. The one-way valve can achieve positive sealing under low pressure and positive opening under high pressure. The fuel distributor proposed by the present invention has multiple functions, a simple structure, and high reliability.

Description

Technical Field

[0001] The invention belongs to the field of aviation auxiliary power devices and relates to a fuel distributor, in particular to a fuel distributor with oil and air discharge functions. Background Art

[0002] The main function of an aviation auxiliary power unit's fuel distributor is to rationally distribute fuel to each fuel line when the combustion chamber uses dual or multiple fuel lines, ensuring that the combustion chamber nozzle has a good atomization effect at a small fuel flow rate; and at a large fuel flow rate, the pressure in front of the nozzle is not too high. The fuel distributor in existing aviation auxiliary power units only has the function of distributing fuel to the nozzles of each fuel line on demand. In practice, when the fuel system of an aviation auxiliary power unit is unsealed, the oil seals filled in it need to be discharged. The traditional unsealing method is mainly to dismantle the fuel line in front of the combustion chamber and then discharge the oil seals out of the auxiliary power unit by faking the start of the operation. This unsealing method requires disassembling the fuel line after the auxiliary power unit is installed on the aircraft. However, the installation space of the auxiliary power unit is often relatively limited, and the disassembly operation is very inconvenient. At the same time, the auxiliary power unit is generally equipped with an oil drain and air vent valve at the interface with the aircraft fuel system to remove gas from the aircraft fuel supply pipeline, thereby improving the starting success rate of the auxiliary power unit. However, this method cannot effectively remove gas from the auxiliary power unit fuel system accessories. Often, after disassembling and installing the auxiliary power unit fuel system accessories, multiple false starts and cold runs are required to ensure the successful starting of the auxiliary power unit. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention meets the functional requirements of unsealing and draining oil of the auxiliary power unit and venting air of the main body accessories, improves the convenience of unsealing and the success rate of starting of the aviation auxiliary power unit, and provides a fuel distributor with oil draining and air venting functions, including a main shell and a one-way valve. A transverse passage and a longitudinal passage are arranged in the main shell, and the transverse passage and the longitudinal passage are cross-connected. One end of the transverse passage is an oil inlet passage, and the other end is an auxiliary oil passage, and the auxiliary oil passage is provided with a one-way valve; one end of the longitudinal passage is a main oil passage, and the other end is an oil drain passage; a three-way push rod, a first spring and a retaining ring are arranged in the oil drain passage, and the three-way push rod is provided in the oil drain passage. The rod is cylindrical, with a blind hole provided in the longitudinal direction at the upper end, and the bottom of the blind hole is open to both sides, forming a three-way structure; the first spring is sleeved outside the three-way push rod, with the upper end abutting against the annular protrusion at the upper end of the three-way push rod, and the lower end abutting against the hole shoulder at the lower part of the oil drain path; a retaining ring is provided above the three-way push rod; when the first spring is reset and the oil pressure is greater than the force of the second spring, the oil inlet path, the main oil path and the auxiliary oil path are connected; the oil drain tool is used to apply downward pressure on the three-way push rod, and the three-way push rod compresses the first spring to move downward, and the ball end of the three-way push rod is sealed with the end port of the main oil path, closing the main oil path, and the openings on both sides connect the oil inlet, the front chamber of the auxiliary oil path and the oil drain path;

[0004] The outer end of the oil drain passage is provided with a plugging cover, which is screwed to the outer end of the oil drain passage; a first sealing ring is sleeved in the groove at the root of the plugging cover; the plugging cover is connected to the outside of the oil drain passage through a chain.

[0005] The one-way valve comprises a first valve body, a second valve body and a ball head push rod, the first valve body and the second valve body are provided with a through hole, one end of the first valve body is connected to the auxiliary oil circuit, and the second valve body is connected to the other end of the first valve body; the ball head push rod is arranged in the first valve body, and a second spring is sleeved on the tail of the ball head push rod, one end of the second spring abuts against the annular protrusion on the ball head push rod, and the other end abuts against the hole shoulder in the second valve body; when the oil pressure is less than the elastic force of the second spring, the second spring resets, and the top spherical surface of the ball head push rod abuts and seals against the pointed edge orifice in the first valve body; when the oil pressure is greater than the elastic force of the second spring, pressure is applied to the ball head push rod, and the ball head push rod compresses the second spring to move outward, and the first valve body and the second valve body are connected to the auxiliary oil circuit.

[0006] A conical filter screen is provided at the inlet of the through hole of the first valve body of the one-way valve, and the outside of the conical filter screen is fixed by a clamping ring.

[0007] The first valve body of the one-way valve is threadedly connected to the auxiliary oil circuit connecting hole, and a second sealing ring is provided between the first valve body of the one-way valve and the auxiliary oil circuit connecting hole.

[0008] The first valve body and the second valve body of the one-way valve are connected by screws, and a light elastic gasket is provided at the screw connection; a third sealing ring is provided between the first valve body and the second valve body.

[0009] An adjusting washer is provided between the second spring and the annular protrusion of the ball head push rod, for adjusting the elastic force of the second spring.

[0010] The working principle and working process of the present invention:

[0011] When the engine is stopped and the oil is drained, the plug cap is unscrewed and the oil drain tool is screwed in. The oil drain tool exerts a downward force on the three-way push rod, compressing the first spring, and the three-way push rod moves downward to the lower end spherical surface and the port seal of the main oil circuit to close the main oil circuit; at the same time, since the oil pressure in the oil circuit is less than the elastic force of the second spring of the one-way valve, the second spring is reset, and the top spherical surface of the ball head push rod abuts and seals with the sharp edge orifice in the first valve body of the one-way valve. At this time, the main oil circuit and the auxiliary oil circuit are both in a closed state, the oil drain circuit is connected with the oil inlet circuit, and the oil draining starts; after the oil draining is completed, the tool is removed, the first spring resets the three-way push rod, the oil inlet circuit is connected with the main oil circuit, the plug cap is re-screwed to complete the sealing, and oil is supplied from the oil inlet circuit. The oil pressure in the oil circuit is greater than the elastic force of the second spring of the one-way valve, pressuring the ball head push rod, and the ball head push rod compresses the second spring to move outward, and the one-way valve is connected to the auxiliary oil circuit.

[0012] When the auxiliary power unit combustion chamber adopts dual oil circuits for oil supply, the present invention provides fuel of a certain pressure and flow rate to the main and auxiliary oil circuits as required; it can not only meet the requirements of dual oil circuits for oil supply to the auxiliary power unit combustion chamber, but also discharge the oil seal and release the gas inside the main body accessories when the aviation auxiliary power unit is unsealed.

[0013] The one-way valve sealing method of the present invention adopts a line seal between the tip of the first valve body and the spherical surface of the ball head push rod. In order to improve the processing quality of the tip of the first valve body, the one-way valve is designed as a split structure connected by screws. At the same time, a third sealing ring is used to ensure that the connection between the two split parts does not leak oil. A conical filter is added at the inlet of the one-way valve. Compared with the flat filter structure, it can not only meet the pressure loss index of the system, but also effectively prevent foreign matter from entering the inside of the one-way valve and damaging the sealing surface of the first valve body and the ball head push rod, causing the one-way valve seal to fail or the push rod to get stuck. An adjustment washer is added to the bottom end of the second spring of the one-way valve to adjust the elastic force of the second spring to ensure that the one-way valve can smoothly open and reliably close the oil circuit under the corresponding pressure index, which is convenient for product debugging.

[0014] Beneficial effects of the present invention:

[0015] The present invention adds an oil drain function to the fuel distributor, enabling the release of seal oil from the auxiliary power unit during unsealing without disassembling the distributor. This also prevents the seal oil from entering the main fuel system circuit during draining. The one-way valve provides positive sealing under low pressure and positive opening under high pressure. A filter screen is added to the inlet of the one-way valve to effectively prevent foreign matter from entering the valve, thereby avoiding potential seal failure and sticking hazards. The split design of the one-way valve facilitates the machining of the first valve body's sharp edge opening, ensuring effective sealing between the first valve body's sharp edge and the ejector rod's spherical surface. The fuel distributor proposed by the present invention offers multiple functions, a simple structure, and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic cross-sectional view of the overall structure of the present invention;

[0017] Figure 2 It is a schematic cross-sectional view of the one-way valve structure of the present invention;

[0018] 1. Main housing 2. Check valve 3. Oil inlet line 4. Auxiliary oil line 5. Main oil line 6. Oil drain line 7. Three-way push rod 8. First spring 9. Retaining ring 10. First valve body 11. Second valve body 12. Ball push rod 13. Second spring 14. Plug cover 15. First sealing ring 16. Chain 17. Conical filter 18. Retaining ring 19. Second sealing ring 20. Screw 21. Light elastic washer 22. Third sealing ring 23. Adjusting washer. DETAILED DESCRIPTION

[0019] See Figure 1-2 As shown:

[0020] The present invention provides a fuel distributor with oil drain and air release functions, comprising a main housing 1 and a one-way valve 2. The transverse passage and the longitudinal passage in the main housing 1 are vertically cross-connected. The left end of the transverse passage is the oil inlet passage 3, and the right end is the auxiliary oil passage 4. The auxiliary oil passage 4 is provided with a one-way valve 2; the lower end of the longitudinal passage is the main oil passage 5, and the upper end is the oil drain passage 6; a three-way push rod 7, a first spring 8 and a retaining ring 9 are provided in the oil drain passage 6. The three-way push rod 7 is columnar, and a blind hole is provided at the upper end along the longitudinal direction downward, and the bottom of the blind hole is open to the left and right sides to form a three-way structure; the first spring 8 is sleeved on the outside of the three-way push rod 7, and the upper end is connected to the three-way push rod The annular protrusion at the upper end of the rod 7 abuts against the hole shoulder at the lower part of the oil drain path 6; the retaining ring 9 is arranged above the three-way push rod 7 and is threadedly connected to the inner wall of the oil drain path hole, for clamping the three-way push rod 7 and limiting the three-way push rod 7; when the first spring 8 is reset and the oil pressure is greater than the force of the second spring 13, the oil inlet path 3, the main oil path 5 and the auxiliary oil path 4 are connected, and the oil drain tool is used to press the three-way push rod 7 downward, and the three-way push rod 7 compresses the first spring 8 and moves downward. The ball end of the three-way push rod 7 is sealed with the upper end of the main oil path 5, closing the main oil path 5. The openings on both sides connect the oil inlet and the front section of the auxiliary oil path 4 with the oil drain path 6;

[0021] The outer end of the oil drain line 6 is provided with a plugging cover 14, which is screwed to the outer end of the oil drain line 6; a first sealing ring 15 is sleeved in the groove at the root of the plugging cover 14; the plugging cover 14 is connected to the outside of the oil drain line 6 through a chain 16.

[0022] The one-way valve 2 includes a first valve body 10, a second valve body 11 and a ball head push rod 12. The first valve body 10 and the second valve body 11 are provided with through holes. The rear end of the first valve body 10 is a protruding hole with a sharp edge opening in the hole. The front end of the first valve body 10 is connected to the auxiliary oil circuit 4. The second valve body 11 is connected to the rear end of the first valve body 10 and is sleeved on the protruding hole at the rear end of the first valve body 10. The ball head push rod 12 is provided in the first valve body 10. The tail of the ball head push rod 12 is sleeved with a second spring 13. The second spring 13 The front end abuts against the annular protrusion on the ball head push rod 12, and the rear end abuts against the hole shoulder in the second valve body 11; when the oil pressure is less than the elastic force of the second spring 13, the second spring 13 resets, and the top spherical surface of the ball head push rod 12 abuts and seals against the sharp edge orifice in the first valve body 10; when the oil pressure is greater than the elastic force of the second spring 13, pressure is applied to the ball head push rod 12, and the ball head push rod 12 compresses the second spring 13 to move backward, and the first valve body 10 and the second valve body 11 are connected to the auxiliary oil circuit 4.

[0023] A conical filter screen 17 is provided at the entrance of the through hole of the first valve body 10 of the one-way valve 2 , and the outside of the conical filter screen 17 is fixed by a clamping ring 18 .

[0024] The first valve body 10 of the one-way valve 2 is screwed to the connecting hole of the auxiliary oil circuit 4 , and a second sealing ring 19 is provided between the first valve body 10 of the one-way valve 2 and the connecting hole of the auxiliary oil circuit 4 .

[0025] The first valve body 10 and the second valve body 11 of the one-way valve 2 are connected by screws 20 , and a light elastic washer 21 is provided at the connection of the screws 20 ; a third sealing ring 22 is provided between the first valve body 10 and the second valve body 11 .

[0026] An adjusting washer 23 is provided between the second spring 13 and the annular protrusion of the ball head push rod 12 for adjusting the elastic force of the second spring 13 .

[0027] The working principle and working process of the present invention:

[0028] When the engine is stopped and the oil is drained, the plug cap 14 is unscrewed and the oil drain tool is screwed in. The oil drain tool exerts a downward force on the three-way push rod 7, compressing the first spring 8. The three-way push rod 7 moves downward until the lower end spherical surface seals with the upper end of the main oil circuit 5 and closes the main oil circuit 5; at the same time, since the oil pressure in the oil circuit is less than the elastic force of the second spring 13 of the one-way valve 2, the second spring 13 resets, and the top spherical surface of the ball head push rod 12 abuts and seals with the sharp edge orifice in the first valve body 10 of the one-way valve 2. At this time, the main oil circuit 5 and the auxiliary oil circuit 4 are all in the closed state, the oil drain path 6 is connected with the oil inlet path 3 and the front chamber of the auxiliary oil path 4, and the oil and air are drained. After the oil is drained, the oil drain tool is removed, the first spring 8 resets the three-way push rod 7, the oil inlet path 3 is connected with the main oil path 5, and the plug 14 is screwed in again to complete the seal. Oil is supplied from the oil inlet path 3. The oil pressure in the oil path is greater than the elastic force of the second spring 13 of the one-way valve 2, and pressure is applied to the ball head push rod 12. The ball head push rod 12 compresses the second spring 13 and moves outward, and the one-way valve 2 is connected with the auxiliary oil path 4.

[0029] The sealing form of the one-way valve 2 of the present invention adopts a line seal between the sharp edge of the first valve body 10 and the spherical surface of the ball head push rod 12. In order to improve the processing quality of the sharp edge orifice of the first valve body 11, the one-way valve 2 is designed as a split structure connected by screws 20. At the same time, a third sealing ring 22 is used to ensure that the connection between the two splits does not leak oil. A conical filter 17 is added at the inlet of the one-way valve 2. Compared with the flat filter structure, it can not only meet the pressure loss index of the system, but also effectively prevent foreign matter from entering the inside of the one-way valve 2 and damaging the sealing surface of the first valve body 10 and the ball head push rod 12, causing the one-way valve 2 to fail to seal or the push rod to get stuck. An adjustment washer 23 is added to the bottom end of the second spring 13 of the one-way valve 2 to adjust the elasticity of the second spring 13 to ensure that the one-way valve 2 can smoothly open and reliably close the oil circuit under the corresponding pressure index, which is convenient for product debugging.

Claims

1. A fuel distributor with oil and air draining functions, characterized by: The invention comprises a main housing (1) and a one-way valve (2). The main housing (1) is provided with a transverse passage and a longitudinal passage, the transverse passage and the longitudinal passage are cross-connected, one end of the transverse passage is an oil inlet passage (3), the other end is an auxiliary oil passage (4), and the auxiliary oil passage (4) is provided with a one-way valve (2); one end of the longitudinal passage is a main oil passage (5), and the other end is an oil discharge passage (6); a three-way push rod (7), a first spring (8) and a retaining ring (9) are provided in the oil discharge passage (6); the three-way push rod (7) is columnar, and a blind hole is provided at the upper end along the longitudinal direction, and the bottom of the blind hole is open to both sides to form a three-way structure; the first spring (8) is sleeved on the three-way push rod (7) ), the upper end of the tee push rod (7) abuts against the annular protrusion at the upper end of the tee push rod (7), and the lower end abuts against the hole shoulder at the lower part of the oil drain path (6); the retaining ring (9) is arranged above the tee push rod (7); when the first spring (8) is reset and the oil pressure is greater than the force of the second spring (13), the oil inlet path (3), the main oil path (5) and the auxiliary oil path (4) are connected; the oil drain tool is used to press the tee push rod (7) downward, the tee push rod (7) compresses the first spring (8) and moves downward, the ball end of the tee push rod (7) is sealed with the upper end of the main oil path (5), closing the main oil path (5), and the openings on both sides connect the oil inlet, the front section of the auxiliary oil path (4) and the oil drain path (6).

2. A fuel distributor with oil and air draining functions according to claim 1, characterized in that: The outer end of the oil drain passage (6) is provided with a blocking cover (14), which is screwed to the outer end of the oil drain passage (6); a first sealing ring (15) is sleeved in a groove at the root of the blocking cover (14); and the blocking cover (14) is connected to the outside of the oil drain passage (6) via a chain (16).

3. The fuel distributor with oil and air draining function according to claim 1, characterized in that: The one-way valve (2) comprises a first valve body (10), a second valve body (11) and a ball-end push rod (12). Through holes are provided inside the first valve body (10) and the second valve body (11). One end of the first valve body (10) is connected to the auxiliary oil circuit (4), and the second valve body (11) is connected to the other end of the first valve body (10). The ball-end push rod (12) is arranged in the first valve body (10). A second spring (13) is sleeved on the tail of the ball-end push rod (12). One end of the second spring (13) is connected to the annular ring on the ball-end push rod (12). The protrusion abuts against the second end, and the other end abuts against the hole shoulder in the second valve body (11); when the oil pressure is less than the elastic force of the second spring (13), the second spring (13) is reset, and the top spherical surface of the ball head push rod (12) abuts against the sharp edge hole in the first valve body (10) to seal; when the oil pressure is greater than the elastic force of the second spring (13), pressure is applied to the ball head push rod (12), and the ball head push rod (12) compresses the second spring (13) to move outward, and the first valve body (10) and the second valve body (11) are connected to the auxiliary oil circuit (4).

4. A fuel distributor with oil and air draining functions according to claim 3, characterized in that: A conical filter screen (17) is provided at the through hole entrance of the first valve body (10) of the one-way valve (2), and the outside of the conical filter screen (17) is fixed by a clamping ring (18).

5. The fuel distributor with oil and air draining function according to claim 3, characterized in that: The first valve body (10) of the one-way valve (2) is screwed to the connecting hole of the auxiliary oil circuit (4), and a second sealing ring (19) is provided between the first valve body (10) of the one-way valve (2) and the connecting hole of the auxiliary oil circuit (4).

6. The fuel distributor with oil and air draining function according to claim 3, characterized in that: The first valve body (10) and the second valve body (11) of the one-way valve (2) are connected via screws (20), and a light elastic washer (21) is provided at the connection of the screws (20); and a third sealing ring (22) is provided between the first valve body (10) and the second valve body (11).

7. The fuel distributor with oil and air draining function according to claim 3, characterized in that: An adjusting washer (23) is provided between the second spring (13) and the annular protrusion of the ball head push rod (12) for adjusting the elastic force of the second spring (13).

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