Aero-piston engine lubrication labyrinth

Abstract

The application relates to the technical field of aero-engines and discloses a lubricating labyrinth device for an aero-piston engine, which comprises a dry oil sump, an oil inlet pipe, an oil tank, and an oil filtering device; the lower part of the side end of the dry oil sump is horizontally connected to the oil tank through the oil inlet pipe; the oil tank is connected to the lower end surface of the dry oil sump through the oil filtering device; the oil filtering device comprises a first oil return pipe, an oil filter, and a second oil return pipe; one end of the first oil return pipe is connected to the lower end surface of the oil tank, the other end of the first oil return pipe is detachably connected to one end of the oil filter, one end of the second oil return pipe is detachably connected to one end of the oil filter, and the other end of the oil filter is connected to the lower end surface of the dry oil sump; the application is convenient for assisting in filtering and removing impurities from the circulating lubricating oil.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, specifically to a lubrication bypass device for an aero-engine piston. Background Technology

[0002] The lubrication system of an aircraft piston engine is a key part of ensuring the normal operation of the engine. Its main function is to provide the appropriate amount and viscosity of lubricating oil to various moving parts to achieve lubrication, cooling, sealing and cleaning. Because the working environment of aircraft engines is relatively harsh and the requirements for lubrication reliability are high, dry lubrication bypass devices for aircraft piston engines are used to ensure the lubrication reliability of the engine.

[0003] Dry lubrication systems (also known as dry oil lubrication systems or dry sump lubrication systems) are a lubrication technology that contrasts with traditional wet lubrication systems. Their key feature is that instead of storing large amounts of lubricating oil in the oil pan at the bottom of the engine, they use an external, independent oil tank to store the lubricating oil. An oil supply pump draws oil from the external tank, pressurizes it, and delivers it to various friction points on the engine. Then, a return pump (or a multi-stage return pump) quickly draws the lubricated oil back from the crankcase or engine block to the oil tank, ensuring that the crankshaft area remains "dry." This prevents lubrication interruptions caused by oil sloshing during severe turbulence or tilting in the air, thus improving the engine's stability and reliability under complex operating conditions.

[0004] However, in the actual use of the lubrication bypass device for aviation piston engines, when the engine oil is used inside the engine, it will generate metal debris and sludge impurities from inside the engine. Over time, these can easily affect the flow of oil and the lubrication effect, which is a shortcoming and makes it difficult to perform auxiliary filtration and impurity removal on the flowing lubricating oil. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a lubrication bypass device for aircraft piston engines, which facilitates auxiliary filtration and impurity removal of circulating lubricating oil.

[0006] This invention proposes a lubrication bypass device for an aircraft piston engine, comprising a dry oil pan, an oil inlet pipe, a lubricating oil tank, and an oil filter device;

[0007] The lower part of the side of the dry oil pan is horizontally connected to the lubricating oil tank through the oil inlet pipe. The dry oil pan and the lubricating oil tank form a torsion device. The positive pressure of the engine crankcase delivers the engine lubricating oil inside the dry oil pan into the lubricating oil tank through the oil inlet pipe.

[0008] The oil tank is connected to the lower end face of the dry oil pan through an oil filter device. After cooling and settling, the lubricating oil is filtered through the oil filter device and flows back into the dry oil pan for the oil pump to draw and lubricate the engine.

[0009] The oil filtration device includes a first return oil pipe, an oil filter, and a second return oil pipe; one end of the first return oil pipe is connected to the lower end face of the lubricating oil tank, and the other end of the first return oil pipe is detachably connected to one end of the oil filter; one end of the second return oil pipe is detachably connected to one end of the oil filter, and the other end of the oil filter is connected to the lower end face of the dry oil pan.

[0010] The oil filter includes a tubular cavity, a filter element support frame, a filter element, a first flange, and a second flange. The first flange and the second flange are detachably aligned and sealed to the open end faces on both sides of the tubular cavity by bolts. The first flange and the second flange are respectively aligned and fixedly connected to one end of the first return oil pipe and one end of the second return oil pipe. The filter element support frame is housed in the inner circumferential sidewall of the tubular cavity. The filter element is limited and seated in the filter element support frame. Lubricating oil flows into one end of the tubular cavity through the first return oil pipe, then flows through the filter element and through the opening of the filter element support frame through the other end of the tubular cavity into the second return oil pipe and into the dry oil pan, completing the filtration of lubricating oil. The oil filter can be repeatedly disassembled and the filter element replaced to avoid oil circuit blockage.

[0011] The diameter of the middle cavity of the tubular cavity is larger than the diameter of the cavities on both sides of the inner wall of the tubular cavity. The filter element support frame is a hollow frustum structure. The diameter of the inlet end of the filter element support frame is larger than the diameter of the outlet end of the filter element support frame, forming a funnel-shaped flow channel structure. The filter element is fitted into the funnel-shaped flow channel structure of the filter element support frame. The outer wall of the inlet end of the filter element support frame is fixed to the middle cavity wall of the tubular cavity. The large diameter in the middle of the inner wall of the tubular cavity can ensure that the flow rate of lubricating oil entering the tubular cavity is slowed down, increasing the filtration of impurities in the lubricating oil by the filter element.

[0012] The second return oil pipe is equipped with a one-way shut-off valve to prevent the filtered lubricating oil flowing into the dry oil pan from flowing back into the lubricating oil tank.

[0013] The oil tank includes a conformal cylinder to reasonably ensure the oil outlet space of the oil tank according to the space of the aircraft engine compartment. The lower end face of the conformal cylinder is provided with an oil return port, and the lower part of the side wall of the conformal cylinder is provided with an oil inlet. One end of the oil inlet pipe is connected to the oil inlet, and one end of the first oil return pipe is connected to the oil return port.

[0014] A fuel pressure relief valve is fixedly connected to the upper end face of the conformal cylinder. The fuel pressure relief valve opens at 450 kPa to release pressure and prevent high-pressure gas from being generated in the lubricating oil tank in high temperature, which could damage the lubricating oil tank.

[0015] The upper end face of the conformal cylinder is connected to the turbocharger return oil pipeline, which can guide the oil after the turbocharger is lubricated and cooled into the lubricating oil tank.

[0016] A lubrication bypass device for an aircraft piston engine, further comprising a lubricating oil detection device, which includes an inner cylinder with an open upper end. The outer wall of the upper part of the inner cylinder is screwed onto the upper end face of a conformal cylinder body. The lower end of the inner cylinder is housed within the inner cavity of the conformal cylinder body, and the lower end face of the inner cylinder is suspended above the bottom wall of the conformal cylinder body. Several inlets are circumferentially opened on the lower part of the inner cylinder side wall, allowing lubricating oil to enter the inner cylinder. The upper end of the inner cylinder protrudes outside the upper end face of the conformal cylinder body. The upper end of the outer wall of the inner cylinder can be threaded and fixed to an end cap to maintain a relatively sealed state of the conformal cylinder body, facilitating the flow of lubricating oil back to the dry oil pan through a filter. A float is housed in contact with the bottom wall of the inner cylinder. A scale plate is fixedly connected to the upper end of the float, and the upper end of the scale plate contacts the inner top wall of the end cap. The float and the scale plate can limit... The float is located within the space where the end cap and inner cylinder are fastened together. The float can move the scale plate up and down along the inner wall of the inner cylinder. When the lubricating oil in the cavity of the conformal cylinder is full, it can flow into the inner wall of the inner cylinder through several inlets. When the end cap is not open, the float and scale plate are limited by the end cap, and the upper end of the lubricating oil level rises synchronously to the corresponding position in the inner cylinder, submerging the float and scale plate limited by the end cap. When it is necessary to test the lubricating oil of a stationary aircraft, the end cap is unscrewed, and the float and scale plate rise under the buoyancy of the lubricating oil. The upper part of the scale plate is exposed outside the upper end of the inner cylinder opening, and the float can float and rotate on the upper end of the lubricating oil. The operator can easily read the oil position information from any angle, and at the same time, judge whether the lubricating oil has deteriorated and needs to be replaced from the color of the lubricating oil attached to the scale plate.

[0017] The oil inlet pipe, lubricating tank, and oil filtration device are all made of aluminum alloy. The filter element is made of glass fiber composite filter media, synthetic composite fiber, stainless steel sintered mesh, and / or magnetic composite structure filter media. The glass fiber composite filter media is specifically designed to intercept tiny metal shavings from pistons and bearings. The synthetic composite fiber is a polyester + wood pulp blend impregnated with resin, with a precision of 10-20μm, dense pleats, large dust holding capacity, low pressure loss, and high cost performance. The stainless steel sintered mesh is made of 304 / 316 stainless steel multi-layer sintering, which can be washed and reused, and is resistant to high pressure and heavy oil corrosion. It has a precision of 25-50μm and intercepts large particulate impurities. The magnetic composite structure filter media has built-in permanent magnets that physically adsorb iron filings, providing double protection when combined with the glass fiber main filter.

[0018] Beneficial effects

[0019] This invention facilitates auxiliary filtration and impurity removal of circulating lubricating oil. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a three-dimensional exploded view of the oil filtration device of the present invention.

[0022] Figure 3 This is a cross-sectional structural diagram of the oil filtration device of the present invention.

[0023] Figure 4 This is a schematic diagram of the cross-sectional structure of the lubricating oil tank of the present invention.

[0024] Figure 5 This is a schematic diagram of the structure of the lubricating oil detection device of the present invention.

[0025] Figure 6 This is a schematic diagram of the float and scale plate structure of the present invention.

[0026] In the picture:

[0027] 1. Dry sump;

[0028] 2. Oil inlet pipe;

[0029] 3. Lubricating oil tank;

[0030] 31. Irregularly shaped cylindrical body;

[0031] 32. Oil return port;

[0032] 33. Oil inlet;

[0033] 34. Fuel pressure relief valve;

[0034] 35. Turbocharger return oil line;

[0035] 4. Oil filtration device;

[0036] 41. First return oil pipe;

[0037] 42. Oil filter;

[0038] 421. Tubular cavity;

[0039] 422. Filter element support frame;

[0040] 423. Filter element;

[0041] 424. First flange;

[0042] 425. Second flange;

[0043] 43. Second return oil pipe;

[0044] 5. Lubricating oil testing device;

[0045] 51. Inner cylinder;

[0046] 52. Liquid inlet;

[0047] 53. End cap;

[0048] 54. Float;

[0049] 55. Scale plate. Detailed Implementation

[0050] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0051] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0052] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0053] Example 1

[0054] See Figures 1-6 As shown, a lubrication and ventilation device for an aircraft piston engine includes a dry oil pan 1, an oil inlet pipe 2, an oil tank 3, and an oil filter device 4.

[0055] The lower part of the side end of the dry oil pan 1 is horizontally connected to the lubricating oil tank 3 through an oil inlet pipe;

[0056] The lubricating oil tank 3 is connected to the lower end face of the dry oil pan 1 through the oil filter device 4.

[0057] The oil filtration device 4 includes a first return oil pipe 41, an oil filter 42, and a second return oil pipe 43. One end of the first return oil pipe 41 is connected to the lower end face of the lubricating oil tank 3, and the other end of the first return oil pipe 41 is detachably connected to one end of the oil filter 42. One end of the second return oil pipe 43 is detachably connected to one end of the oil filter 42, and the other end of the oil filter 42 is connected to the lower end face of the dry oil pan.

[0058] The oil filter 42 includes a tubular cavity 421, a filter element support frame 422, a filter element 423, a first flange 424, and a second flange 425. The first flange 424 and the second flange 425 are respectively detachably aligned and sealed to the open end faces on both sides of the tubular cavity 421 by bolts. The first flange 424 and the second flange 425 are respectively aligned and fixedly connected to one end of the first return oil pipe 41 and one end of the second return oil pipe 43. The filter element support frame 422 is housed in the inner circumferential side wall of the tubular cavity 421, and the filter element 423 is limited and seated in the filter element support frame 422.

[0059] The diameter of the middle cavity of the inner wall of the tubular cavity 421 is larger than the diameter of the cavities on both sides of the inner wall of the tubular cavity 421. The filter element support frame 422 is a hollow frustum structure. The diameter of the inlet end of the filter element support frame 422 is larger than the diameter of the outlet end of the filter element support frame 422, forming a funnel-shaped flow channel structure. The filter element 423 is fitted into the funnel-shaped flow channel structure of the filter element support frame 422 in a matching shape. The outer side wall of the inlet end of the filter element support frame 422 is fixed to the middle cavity wall of the inner wall of the tubular cavity 421.

[0060] A one-way shut-off valve is installed on the second return oil pipe 43.

[0061] The lubricating oil tank 3 includes a conformal cylindrical body 31, with an oil return port 32 on the lower end face of the conformal cylindrical body 31, an oil inlet 33 on the lower part of the side wall of the conformal cylindrical body 31, one end of the oil inlet pipe 2 being connected to the oil inlet 33, and one end of the first oil return pipe 41 being connected to the oil return port 32.

[0062] The upper end face of the conformal cylinder 31 is connected to the turbocharger return oil pipeline 35.

[0063] The oil inlet pipe 2, the lubricating oil tank 3, and the oil filtration device 4 are all made of aluminum alloy. The filter element 423 is made of glass fiber composite filter material, synthetic composite fiber, stainless steel sintered mesh, and / or magnetic composite structure filter material.

[0064] Example 2

[0065] See Figure 1 As shown, a lubrication bypass device for an aircraft piston engine differs from other embodiments in that a fuel pressure relief valve 34 is fixedly connected to the upper end face of the conformal cylinder 31, and the fuel pressure relief valve 34 opens to relieve pressure at 450 kPa.

[0066] Example 3

[0067] See Figure 1 , Figures 4-6As shown, a lubrication bypass device for an aircraft piston engine also includes a lubricating oil detection device 5. The lubricating oil detection device 5 includes an inner cylinder 51 with an open upper end. The upper outer wall of the inner cylinder 51 is screwed onto the upper end face of a conformal cylindrical body 31. The lower end of the inner cylinder 51 is housed within the inner cavity of the conformal cylindrical body 31, and the lower end face of the inner cylinder 51 is suspended above the inner bottom wall of the conformal cylindrical body 31. Twenty-six liquid inlets 52 are circumferentially opened on the lower part of the side wall of the inner cylinder 51. The upper end of the inner cylinder 51 is exposed... Located outside the upper end face of the conformal cylindrical body 31, the upper end of the outer wall of the inner cylinder 51 can be threaded and fixed to the end cap 53. The inner bottom wall of the inner cylinder 51 is in contact with and accommodates a float 54. The upper end of the float 54 is fixedly connected to a scale plate 55. The upper end of the scale plate 55 is in contact with the inner top wall of the end cap 53. The float 54 and the scale plate 55 can be limited and accommodated in the space where the end cap 53 and the inner cylinder 51 are fastened and fixed. The float 54 can drive the scale plate 55 to move up and down along the inner side wall of the inner cylinder 51.

[0068] Working principle

[0069] The dry sump 1 provides continuous oil supply during equipment tilting or severe shaking, preventing lubrication failure. The external oil tank 3 has a larger capacity, storing more oil. When the crankcase system is operating, the positive pressure of the engine crankcase allows the lubricating oil inside the dry sump 1 to be transported into the oil tank 3 via the inlet pipe 2. Then, it flows back to the dry sump 1 via the first return pipe 41 and the second return pipe 43 for lubrication by the oil pump. During the return process, the oil drawn from inside the engine enters the tubular cavity 421, where it is further lubricated. The filter element 423 installed inside the body 421 can filter and clean the oil containing debris and impurities, reducing the impurity content in the oil. In addition, when the through-flow system is installed and used, after unscrewing the end cap 53 through the lubricating oil detection device 5, the float 54 inside the inner cylinder 51 can move upward under the push of the oil, and at the same time push the scale plate 55 out of the upper opening of the inner cylinder 51. The preset scale on the scale plate 55 can be used to quickly detect the oil level in the oil tank 3 and judge the oil quality, avoiding the inconvenience of inspection in a dark environment during maintenance.

[0070] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A lubrication bypass device for an aircraft piston engine, characterized in that: Includes a dry oil sump (1), an oil inlet pipe (2), a lubricating oil tank (3), and an oil filter device (4); The lower part of the side end of the dry oil pan (1) is horizontally connected to the lubricating oil tank (3) through the oil inlet pipe. The lubricating oil tank (3) is connected to the lower end face of the dry oil pan (1) through the oil filter device (4).

2. The lubrication bypass device for an aircraft piston engine according to claim 1, characterized in that: The oil filtration device (4) includes a first return oil pipe (41), an oil filter (42), and a second return oil pipe (43). One end of the first return oil pipe (41) is connected to the lower end face of the lubricating oil tank (3), and the other end of the first return oil pipe (41) is detachably connected to one end of the oil filter (42). One end of the second return oil pipe (43) is detachably connected to one end of the oil filter (42), and the other end of the oil filter (42) is connected to the lower end face of the dry oil pan.

3. The lubrication bypass device for an aircraft piston engine according to claim 2, characterized in that: The oil filter (42) includes a tubular cavity (421), a filter element support frame (422), a filter element (423), a first flange (424), and a second flange (425). The first flange (424) and the second flange (425) are respectively detachably aligned and sealed to the open end faces on both sides of the tubular cavity (421) by bolts. The first flange (424) and the second flange (425) are respectively aligned and fixedly connected to one end of the first return oil pipe (41) and one end of the second return oil pipe (43). The filter element support frame (422) is housed in the inner side wall of the tubular cavity (421), and the filter element (423) is limited and seated in the filter element support frame (422).

4. The lubrication bypass device for an aircraft piston engine according to claim 3, characterized in that: The diameter of the middle cavity of the inner wall of the tubular cavity (421) is larger than the diameter of the cavities on both sides of the inner wall of the tubular cavity (421). The filter element support frame (422) is a hollow frustum structure. The diameter of the inlet end of the filter element support frame (422) is larger than the diameter of the outlet end of the filter element support frame (422), forming a funnel-shaped liquid flow channel structure. The filter element (423) is fitted in the funnel-shaped liquid flow channel structure of the filter element support frame (422) with a matching shape. The outer side wall of the inlet end of the filter element support frame (422) is fixed to the middle cavity wall of the inner wall of the tubular cavity (421).

5. The lubrication bypass device for an aircraft piston engine according to claim 4, characterized in that: A one-way shut-off valve is installed on the second return oil pipe (43).

6. The lubrication bypass device for an aircraft piston engine according to claim 5, characterized in that: The lubricating oil tank (3) includes a conformal cylindrical body (31), with an oil return port (32) on the lower end face of the conformal cylindrical body (31) and an oil inlet (33) on the lower part of the side wall of the conformal cylindrical body (31). One end of the oil inlet pipe (2) is connected to the oil inlet (33), and one end of the first oil return pipe (41) is connected to the oil return port (32).

7. The lubrication bypass device for an aircraft piston engine according to claim 6, characterized in that: A fuel pressure relief valve (34) is fixedly connected to the upper end face of the conformal cylinder (31), and the fuel pressure relief valve (34) opens to relieve pressure at 450 kPa.

8. The lubrication bypass device for an aircraft piston engine according to claim 7, characterized in that: The upper end face of the conformal cylinder (31) is connected to the turbocharger return oil pipeline (35).

9. A lubrication bypass device for an aircraft piston engine according to claim 8, characterized in that: It also includes a lubricating oil detection device (5), which includes an inner cylinder (51) with an open upper end. The upper outer wall of the inner cylinder (51) is screwed to the upper end face of the conformal cylinder (31). The lower end of the inner cylinder (51) is housed in the inner cavity of the conformal cylinder (31), and the lower end face of the inner cylinder (51) is suspended above the inner bottom wall of the conformal cylinder (31). Several liquid inlets (52) are circumferentially opened on the lower part of the side wall of the inner cylinder (51), and the upper end of the inner cylinder (51) is exposed outside the upper end face of the conformal cylinder (31). The upper end of the outer wall of the inner cylinder (51) can be threaded and fixed to the end cap (53). The bottom wall of the inner cylinder (51) is in contact with and accommodates a float (54). The upper end of the float (54) is fixedly connected to a scale plate (55). The upper end of the scale plate (55) is in contact with the top wall of the end cap (53). The float (54) and the scale plate (55) can be limited and accommodated in the space where the end cap (53) and the inner cylinder (51) are fastened and fixed. The float (54) can drive the scale plate (55) to move up and down along the inner wall of the inner cylinder (51).

10. A lubrication bypass device for an aircraft piston engine according to claim 9, characterized in that: The oil inlet pipe (2), lubricating oil tank (3) and oil filtration device (4) are all made of aluminum alloy. The filter element (423) is made of glass fiber composite filter material, synthetic composite fiber, stainless steel sintered mesh and / or magnetic composite structure filter material.

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