Stretchable multi-section shaft core fan shaft oil throwing structure

Abstract

The application provides a stretchable multi-section shaft oil throwing structure of an axial fan, the oil throwing structure is circular and is arranged outside a fan shaft of a centrifugal ventilator, is located between a plunger pipe and a first bearing of the centrifugal ventilator, and can stretch and contract in the radial direction of the fan shaft; the oil throwing structure comprises at least two stages of oil throwing discs, a first-stage oil throwing disc is fixedly arranged outside the fan shaft, and a second-stage oil throwing disc is movably connected outside the first-stage oil throwing disc and can stretch outwards in the radial direction of the fan shaft under the centrifugal force. The oil throwing structure can better promote the separation of lubricating oil from an oil-gas mixture and promote ventilation oil return, and the oil throwing structure is a stretchable multi-section structure, which is novel in structure and can match ventilation oil return under different speed sections.

Description

Technical Field

[0001] This invention relates to the field of bearing cavity ventilation and oil return technology, specifically to a stretchable multi-segment shaft oil-throwing structure for a axial fan. Background Technology

[0002] The power transmission of an aero-engine primarily comes from the work done by gas on the turbine. Hot air from the combustion chamber rotates the main shaft and drives other accessories. These mechanical transmissions all require a lubrication system to ensure their reliability. During operation, pressurized air is used to seal the main bearing system of the aero-engine. Some of the air involved in the sealing process enters the bearing cavity, where it mixes with lubricating oil to form an oil-air mixture. Allowing this mixture to exit directly from the bearing cavity would result in significant oil loss. Since the lubricating oil reserve in an aero-engine is limited, excessive oil consumption will inevitably affect the engine's mechanical performance, thereby impacting other key performance characteristics.

[0003] Therefore, a ventilator is installed in the ventilation path between the bearing cavity and the outside to separate the lubricating oil from the air, thereby reducing lubricating oil consumption. Typical ventilators include centrifugal ventilators, impeller ventilators, and axial ventilators.

[0004] Large civilian aircraft engines have higher power outputs and generate more heat. Compared to the smaller engines in military aircraft, the larger engines used in civilian aircraft require more lubricating oil to lubricate and cool the components. Therefore, more efficient ventilator structures are needed to separate the lubricating oil and reduce oil consumption.

[0005] The most mature ventilator structure currently available is the plunger-tube type axial ventilator, which mainly consists of multiple plunger tubes and a fan shaft. Each plunger tube is installed in the through hole of the fan shaft. When the oil-gas mixture enters the plunger tube, the lubricating oil is separated by centrifugal force, flowing out from the oil return groove on the plunger tube. The gas, with its lower density and inertia, is discharged from the central channel of the fan shaft, thus completing the ventilation and oil return of the entire system.

[0006] The axial ventilator, a relatively mature centrifugal ventilator structure for aero engines, is mounted on the low-pressure shaft of the engine. This type of centrifugal ventilator has been widely used in various models and its structure is quite mature. However, during actual engine testing, noticeable white mist is still observed at the engine's central tail cone, indicating room for improvement in the centrifugal ventilator's oil separation capability. This invention addresses this issue by improving and optimizing the fan shaft structure that drives the entire centrifugal ventilator, thereby enhancing its separation efficiency.

[0007] In view of this, the inventors of this application have designed a stretchable multi-segment axial fan shaft oil-throwing structure in order to overcome the above-mentioned technical problems. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to overcome the deficiency of insufficient oil separation capacity of centrifugal ventilators in the prior art, and to provide a stretchable multi-segment axial fan shaft oil-throwing structure.

[0009] The present invention solves the above-mentioned technical problems through the following technical solution:

[0010] This invention provides a stretchable multi-segment axial fan shaft oil-throwing structure, characterized in that the oil-throwing structure is annular, surrounding and disposed on the outside of the fan shaft of a centrifugal ventilator, located between the plunger tube and the first bearing of the centrifugal ventilator, and the oil-throwing structure can extend and retract in the radial direction of the fan shaft; the oil-throwing structure includes at least two stages of oil-throwing discs, the first stage oil-throwing disc is fixedly disposed on the outside of the fan shaft, and the second stage oil-throwing disc is movably connected to the outside of the first stage oil-throwing disc, and under centrifugal force, the second stage oil-throwing disc can extend outward in the radial direction of the fan shaft.

[0011] According to one embodiment of the present invention, each stage of the oil slinger is provided with a plurality of oil return grooves in the radial direction, and each oil return groove penetrates the radial upper surface and the bottom reference surface of each stage of the oil slinger.

[0012] According to one embodiment of the present invention, the oil-throwing structure includes three-stage oil-throwing discs. The first-stage oil-throwing disc is fixedly disposed on the outside of the fan shaft, the second-stage oil-throwing disc is movably connected to the outside of the first-stage oil-throwing disc, and the third-stage oil-throwing disc is movably connected to the outside of the second-stage oil-throwing disc. Under the action of centrifugal force, the second-stage oil-throwing disc and the third-stage oil-throwing disc can extend outward in the radial direction of the fan shaft.

[0013] According to one embodiment of the present invention, the oil-slinging structure is integrally connected to the fan shaft.

[0014] According to one embodiment of the present invention, the oil return groove has a rotation direction, and the rotation direction of the oil return groove is consistent with the rotation direction of the fan shaft.

[0015] According to one embodiment of the present invention, the rotation direction, included angle and width of each of the oil return grooves are the same.

[0016] According to one embodiment of the present invention, a plurality of oil return grooves are simultaneously provided on the left end face and the right end face of each stage of the oil slinger, and the number of oil return grooves on the left end face and the right end face are the same and symmetrically arranged.

[0017] According to one embodiment of the present invention, the depth of the oil return groove is 1mm to 2mm.

[0018] According to one embodiment of the present invention, the oil return grooves on the secondary oil slinger and the oil return grooves on the primary oil slinger are distributed alternately.

[0019] According to one embodiment of the present invention, the oil return grooves on the third-stage oil slinger and the oil return grooves on the second-stage oil slinger are distributed alternately.

[0020] According to one embodiment of the present invention, each stage of the oil slinger has a vent hole between every two adjacent oil return grooves.

[0021] According to one embodiment of the present invention, the diameter of the vent hole is 1 mm to 3 mm.

[0022] According to one embodiment of the present invention, the vent is positioned higher than the inlet end face of the plunger tube.

[0023] According to one embodiment of the present invention, the central axes of the oil slingers at each stage coincide.

[0024] According to one embodiment of the present invention, the width of each oil-slinging disc decreases progressively.

[0025] The positive and progressive effects of this invention are as follows:

[0026] The stretchable multi-segment axial fan shaft oil-throwing structure of the present invention has at least the following advantages:

[0027] First, it breaks through the traditional form of aero-engine fan shaft structure and proposes a brand-new form of fan shaft structure, opening up new ideas for the design of the entire lubrication system of aero-engines.

[0028] Second, an oil-slinging structure is installed on the fan shaft to better promote the separation of lubricating oil from the oil-gas mixture and facilitate ventilation and oil return.

[0029] Third, the oil slinger structure on the fan shaft is a stretchable multi-segment structure with a novel structural form, which can match the ventilation oil return at different speed ranges.

[0030] Fourth, because oil return grooves and ventilation holes are opened on the surface of each section of the oil-slinging structure, the structure can both sling oil and provide ventilation.

[0031] Fifth, it can further improve the performance of the centrifugal ventilator on the original basis, increase the oil return capacity, reduce the lubricating oil consumption, especially the lubricating oil of the main shaft bearing in the front bearing cavity, while not affecting the ventilation function of the centrifugal ventilator. Attached Figure Description

[0032] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always denote the same features, wherein:

[0033] Figure 1A This is a schematic diagram illustrating the working principle of a centrifugal ventilator using existing technology.

[0034] Figure 1B yes Figure 1A Enlarged schematic diagram of part A.

[0035] Figure 2A This is a schematic diagram illustrating the working principle of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0036] Figure 2B yes Figure 2A Enlarged schematic diagram of part B.

[0037] Figure 3A This is a schematic diagram of the single-segment state of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0038] Figure 3B This is a schematic diagram of the two-section state of the stretchable multi-section shaft oil-throwing structure of the present invention.

[0039] Figure 3C This is a schematic diagram of the three-section state of the stretchable multi-section shaft oil-throwing structure of the present invention.

[0040] Figure 4A This is a schematic diagram of the structural relationship between the stretchable multi-segment axial fan shaft oil-throwing structure and the fan shaft of the present invention.

[0041] Figure 4B yes Figure 4A Enlarged schematic diagram of part C.

[0042] Figure 5A This is a three-dimensional schematic diagram of the structural relationship between the oil return groove and the fan shaft of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0043] Figure 5B yes Figure 5A Enlarged schematic diagram of part D.

[0044] Figure 5C This is a front view schematic diagram showing the structural relationship between the oil return groove and the fan shaft of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0045] Figure 5D This is an enlarged schematic diagram showing the structural relationship between the oil return groove and the fan shaft in the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0046] Figure 6A This is a front view schematic diagram of the layout of the oil return groove of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention on the oil-throwing structure.

[0047] Figure 6B This is a frontal perspective three-dimensional schematic diagram of the layout of the oil return groove of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention on the oil-throwing structure.

[0048] Figure 6C This is a rear-view three-dimensional schematic diagram of the layout of the oil return groove of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention on the oil-throwing structure.

[0049] Figure 7A This is a schematic diagram showing the positional relationship between the oil return grooves on both ends of the oil-throwing structure of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0050] Figure 7B yes Figure 7A Enlarged schematic diagram of part F.

[0051] Figure 8A This is a first three-dimensional schematic diagram showing the positional relationship of the ventilation holes of the stretchable multi-segment axial fan shaft oil-throwing structure on both sides of the oil-throwing structure.

[0052] Figure 8B This is a second three-dimensional schematic diagram showing the positional relationship of the ventilation holes of the stretchable multi-segment axial fan shaft oil-throwing structure on both sides of the oil-throwing structure.

[0053] Figure 8C yes Figure 8B Enlarged schematic diagram of part G.

[0054] Figure 8D This is a front view schematic diagram showing the positional relationship of the ventilation holes of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention on both ends of the oil-throwing structure.

[0055] Figure 9A This is a schematic diagram showing that the ventilation hole of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention is positioned radially higher than the inlet end face of the plunger tube.

[0056] Figure 9B This is a schematic diagram showing that the ventilation hole of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention is located radially below the inlet end face of the plunger tube.

[0057] Figure 10A This is a first partial cross-sectional schematic diagram of the complete structure of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0058] Figure 10B This is a front view schematic diagram of the complete structure of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0059] Figure 10C This is a side view schematic diagram of the complete structure of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0060] Figure 10D This is a second partial cross-sectional schematic diagram of the complete structure of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention.

[0061] [Attached image labels]

[0062] Fan shaft 100

[0063] Fan shaft radial end face 110

[0064] 200 plunger tube

[0065] 210 Plunger tube inlet end face

[0066] First bearing 300

[0067] Oil return port 400

[0068] Oil-slinging structure 500

[0069] 510a First-stage oil slinger

[0070] Secondary oil slinger 510b

[0071] 510c Three-stage oil-slinging disc

[0072] Oil return tank 520

[0073] Vent 530

[0074] Radial upper surface 540

[0075] Bottom reference plane 550

[0076] Second bearing 600

[0077] Rear vent 700

[0078] Front vent 800

[0079] Oil supply pipe 900

[0080] 1000 oil nozzle

[0081] Nozzle 1100 Detailed Implementation

[0082] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0083] Embodiments of the invention will now be described in detail with reference to the accompanying drawings. Preferred embodiments of the invention will now be described in detail, examples of which are shown in the drawings. Wherever possible, the same reference numerals will be used in all the drawings to denote the same or similar parts.

[0084] Furthermore, although the terminology used in this invention is selected from commonly known and used terms, some terms mentioned in this specification may have been selected by the applicant in his or her judgment, and their detailed meanings are explained in the relevant sections of the description herein.

[0085] Furthermore, the invention should be understood not only through the actual terminology used, but also through the meaning implied by each term.

[0086] Figure 1A and Figure 1B The working principle of a centrifugal ventilator is demonstrated. The centrifugal ventilator mainly consists of two parts: a fan shaft 100 and several plunger tubes 200. After the oil-air mixture passes through the plunger tubes 200, under the centrifugal force generated by the high-speed rotation of the fan shaft 100, the lubricating oil is separated and flows out from the oil return port 400, while the air flows out from the channel in the center of the fan shaft 100. This is the working principle and process of the entire ventilation and oil return system.

[0087] Regarding the sources of the oil-air mixture, the air mainly comes from two places: the front vent 800 and the rear vent 700. The lubricating oil also mainly comes from two places: the first bearing 300 and the second bearing 600. The first bearing 300 is usually a rod bearing, and the second bearing 600 is usually a ball bearing.

[0088] Taking a first bearing 300 as a bar bearing and a second bearing 600 as a ball bearing as an example: the ball bearing 600 uses an under-ring oil supply method and is far from the inlet of the plunger tube 200. Under the centrifugal force of the fan shaft 100, most of the lubricating oil from the ball bearing can smoothly return to the oil return port 400. However, the lubricating oil flowing out of the bar bearing 300 is closer to the plunger tube 200 and can enter the plunger tube 200 in a very short time, which will have a certain impact on the separation efficiency of the centrifugal fan.

[0089] The lubricating oil for the rod bearing 300, the first bearing, is supplied by the oil supply pipe 900. Under pressure, the lubricating oil flows from the oil supply pipe 900 into the lubricating oil nozzle 1000, and finally exits from the spray hole 1100. This is a typical jet lubrication method for lubricating the rod bearing. Therefore, some lubricating oil will flow out of the rod bearing and into the centrifugal ventilator, requiring return through the ventilator, and finally flowing out from the return port 400. Because the lubricating oil exiting the rod bearing is relatively close to the plunger pipe 200, a significant amount of lubricating oil may flow into the plunger pipe 200 in a short period of time. This can cause some lubricating oil to fail to be separated and flow out with the airflow from the central channel of the fan shaft 100, potentially increasing lubricating oil consumption.

[0090] To address the aforementioned risks, this invention improves the structure of the fan shaft 100 by adding an oil-throwing structure 500 to the original fan shaft 100. This structure blocks the lubricating oil flowing out of the rod bearing, which serves as the first bearing 300. Instead of directly entering the plunger tube 200, the lubricating oil bypasses the oil-throwing structure 500 and is thrown onto the wall of the bearing cavity. The lubricating oil then flows out through the return oil system due to gravity and the suction of the return oil pump, thus achieving the effect of oil return.

[0091] like Figures 2A-2B , Figures 3A-3C As shown, the present invention discloses a stretchable multi-segment axial fan shaft oil-throwing structure. The oil-throwing structure 500 is annular and is arranged around the outside of the fan shaft 100 of the centrifugal ventilator, located between the plunger tube 200 and the first bearing 300 of the centrifugal ventilator. The oil-throwing structure 500 can extend and retract along the radial direction of the fan shaft 100.

[0092] The oil slinger structure 500 includes at least two stages of oil slinger discs. The first stage oil slinger disc 510a is fixedly disposed on the outside of the fan shaft 100, and the second stage oil slinger disc 510b is movably connected to the outside of the first stage oil slinger disc 510a. Under centrifugal force, the second stage oil slinger disc 510b can extend outward in the radial direction of the fan shaft 100.

[0093] Under the centrifugal force generated by the rotation of the fan shaft 100, the oil-throwing structure 500 is stretched into different states. Therefore, the state of the oil-throwing structure 500 will be different at different speeds. When the oil-throwing structure 500 is stretched to its limit, its surface area is the largest, and its oil-throwing capacity is the strongest. At the same time, under higher speed conditions, the oil supply is larger, and more oil leaks from the rod bearing, which is the first bearing 300. Therefore, a matching state of the oil-throwing structure 500 is needed to throw away the oil, thereby enabling better oil return and ventilation.

[0094] Since the oil-slinging structure 500 of the present invention is set on the fan shaft 100, located between the plunger tube 200 and the first bearing 300 of the centrifugal ventilator, it can better promote the separation of lubricating oil from the oil-gas mixture and promote ventilation oil return.

[0095] Since the oil-slinging structure 500 of the present invention is a stretchable multi-segment structure, its structural form is novel and can match the ventilation oil return at different speed ranges.

[0096] The oil-slinging structure 500 of the present invention can further improve the performance of the centrifugal ventilator on the original basis, increase the oil return capacity, reduce the lubricating oil consumption, especially the lubricating oil of the main shaft bearing in the front bearing cavity, and at the same time, it does not affect the ventilation function of the centrifugal ventilator.

[0097] like Figures 5A to 5D As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, each stage of the oil-throwing disc is provided with a plurality of oil return grooves 520 along the radial direction, and each oil return groove 520 penetrates the radial upper surface 540 and the bottom reference surface 550 of each stage of the oil-throwing disc.

[0098] The difference between the oil-slinging structure 500 in the above embodiment and the oil-slinging structure 500 in the prior art is that multiple oil return grooves 520 are opened on the oil-slinging structure 500, which can increase the flow area of ​​lubricating oil on the oil-slinging structure 500. The purpose of this design is to enable better oil return.

[0099] like Figure 5A and Figure 5B The diagram shows the structural relationship between the oil return groove 520 on the oil slinger structure 500 and the fan shaft 100. The oil return groove 520 must be in communication with the outer wall surface of the fan shaft 100 (i.e., the bottom reference surface 550) and the outer surface of the first-stage oil slinger 510a (i.e., the radial upper surface 540 of the oil slinger 540), and there must be no gap between them.

[0100] like Figure 5C and Figure 5D As shown, to explain why gaps are not allowed, it can be seen that there is a certain small gap H between the outer surfaces of the oil return groove 520 and the first-stage oil slinger 510a. This is an unacceptable structure because it will cause lubricating oil to accumulate on one side of the oil return groove 520, which is not conducive to the oil slinger structure 500.

[0101] like Figures 3A-3C , Figures 10A to 10DAs shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the oil-throwing structure 500 includes a three-stage oil-throwing disc 510c. The first-stage oil-throwing disc 510a is fixedly disposed on the outside of the fan shaft 100, the second-stage oil-throwing disc 510b is movably connected to the outside of the first-stage oil-throwing disc 510a, and the third-stage oil-throwing disc 510c is movably connected to the outside of the second-stage oil-throwing disc 510b. Under the action of centrifugal force, the second-stage oil-throwing disc 510b and the third-stage oil-throwing disc 510c can extend outward in the radial direction of the fan shaft 100.

[0102] like Figures 3A-3C As shown, the oil-slinging structure 500 in the above embodiment includes three states: one-stage, two-stage, and three-stage. The oil-slinging structure 500 is retractable, and the state of the oil-slinging structure 500 will be different depending on the rotational speed of the fan shaft 100.

[0103] Based on the engine's operating conditions, the centrifugal ventilator is located on the low-pressure shaft, which is the main shaft with a relatively low rotational speed. According to all operating conditions tested with the entire machine, the centrifugal ventilator's rotational speed ranges from 800 to 4000 rpm. Furthermore, as the rotational speed increases, the oil supply from the lubricating nozzle 1000 also increases. The test results indicate a direct proportional relationship between the oil supply from the lubricating nozzle 1000 and the rotational speed.

[0104] In the above embodiment, the oil-throwing structure 500 is stretched into three different states under the centrifugal force generated by the rotation of the fan shaft 100. The first-stage state corresponds to a speed between 800 and 1300 rpm, the second-stage state corresponds to a speed between 1300 and 1800 rpm, and the third-stage state corresponds to a speed between 1800 and 3000 rpm. The state of the oil-throwing structure 500 will be different at different speeds. When the oil is thrown in the third-stage state, the surface area of ​​the oil-throwing structure 500 is the largest, and the oil-throwing capacity is the strongest. At the same time, under higher operating conditions, the oil supply is larger, and the amount of oil leaking from the rod bearing is also greater. Therefore, a matching state of the oil-throwing structure 500 is needed to throw away the oil, thereby enabling better oil return and ventilation.

[0105] like Figure 4A and Figure 4B As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the oil-throwing structure 500 is integrally connected with the fan shaft 100.

[0106] like Figure 4A and Figure 4BAs shown, the oil-throwing structure 500 in the above embodiment is integrally connected to the fan shaft 100, that is, the two are integrated. The integrated structure can effectively fix the fan shaft 100 and the oil-throwing structure 500, preventing the oil-throwing structure 500 from falling off the fan shaft 100 under the action of large centrifugal force, and has good strength and reliability.

[0107] like Figures 6A to 6C As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the oil return groove 520 has a rotation direction, and the rotation direction of the oil return groove 520 is consistent with the rotation direction of the fan shaft 100.

[0108] The oil return groove 520 in the above embodiment has a certain spiral direction and is not a straight-through structure, such as... Figures 6A to 6C As shown, its rotation direction is the same as the rotation direction E of the fan shaft 100. Figure 6B The diagram shows the rotation direction of the fan shaft 100 under normal engine operation. Therefore, the rotation direction of all oil return grooves 520 on the oil slinger structure 500 is consistent with the rotation direction E of the fan shaft 100. For example... Figure 6C As shown, the oil return groove 520 rotates counterclockwise.

[0109] like Figures 6A to 6C As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the rotation direction, included angle and width of each oil return groove 520 are the same.

[0110] like Figure 6A As shown, the oil return groove 520 in the above embodiment is arranged in a circular manner on the oil throwing structure 500. That is, the product of the included angle α between two adjacent oil return grooves 520 and the number N of oil return grooves 520 on one side end face of the oil throwing structure 500 is equal to 360, that is, α*N=360.

[0111] All the oil return grooves 520 on the oil-throwing structure 500 in the above embodiments have the same structure, that is, the rotation direction, included angle and width of the oil return grooves 520 are the same, which facilitates manufacturing and processing.

[0112] The number N of all oil return grooves 520 in the oil-throwing structure 500 of the present invention is determined by structural CAE finite element strength analysis. While a larger number N of oil return grooves 520 increases the flow area of ​​lubricating oil, it also leads to a decrease in the strength of the oil-throwing structure 500. Therefore, it is necessary to determine the optimal value of the number N of oil return grooves 520 through CAE finite element analysis.

[0113] like Figure 7A and Figure 7BAs shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, multiple oil return grooves 520 are simultaneously provided on the left and right end faces of each stage of the oil-throwing disc. The number of oil return grooves 520 on the left and right end faces is the same and they are arranged symmetrically.

[0114] In the above embodiment, the oil return grooves 520 must be opened on both the left and right end faces of the oil throwing structure 500, and the number of oil return grooves 520 on both end faces must be the same, arranged symmetrically. Therefore, when verifying the strength of the oil throwing structure 500 using CAE finite element analysis, the oil return grooves 520 on both end faces need to be considered.

[0115] like Figure 7B As shown, in the above embodiment, the oil return groove 520 is arranged symmetrically on the two end faces of the oil throwing structure 500. The oil return grooves 520 on both sides cannot be connected to each other. There is a certain limitation on the depth of the oil return groove 520, but the depth of the oil return grooves 520 on both sides must be consistent, that is, m = n.

[0116] As a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the depth of the oil return groove 520 is 1mm to 2mm.

[0117] Considering the overall strength requirements of the oil-slinging structure 500, the depth of the oil return groove 520 cannot be machined too deep, otherwise it is very likely to lead to insufficient strength. Based on CAE finite element strength analysis calculation, the depth of the oil return groove 520 is recommended to be 1mm to 2mm.

[0118] like Figures 10A to 10D As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the oil return groove 520 on the secondary oil-throwing plate 510b and the oil return groove 520 on the primary oil-throwing plate 510a are distributed alternately.

[0119] like Figures 10A to 10D The image shows the complete structure of the oil-slinging structure 500 in the above embodiment. Figure 10B As shown, the distribution of the oil return grooves 520 on the secondary oil slinger 510b is staggered with that on the primary oil slinger 510a to ensure that the lubricating oil can flow out through more pathways, rather than flowing out through the oil return groove 520 that stays in only one path.

[0120] like Figures 10A to 10D As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the oil return grooves 520 on the third-stage oil-throwing plate 510c and the oil return grooves 520 on the second-stage oil-throwing plate 510b are distributed alternately.

[0121] like Figure 10BAs shown, the distribution of the oil return grooves 520 on the third-stage oil slinger 510c and the oil return grooves 520 on the second-stage oil slinger 510b is staggered to ensure that the lubricating oil can flow out from more paths, rather than flowing out from the oil return groove 520 that stays in only one path.

[0122] like Figures 8A to 8D As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, each stage of the oil-throwing disc has a vent hole 530 between every two adjacent oil return grooves 520.

[0123] like Figures 8A to 8D As shown, in the above embodiment, the oil-slinging structure 500, while providing the oil return groove 520, can also provide a vent hole 530 between adjacent oil return grooves 520. The purpose of providing the vent hole 530 is to allow ventilation. Because the lubricating oil flowing out from the rod bearing, which serves as the first bearing 300, also contains air, if the vent hole 530 is not provided on the oil-slinging structure 500, the flow in some areas will be obstructed, which would be detrimental to ventilation.

[0124] like Figure 8D As shown, the vent 530 in the above embodiment is arranged in the middle of the adjacent oil return groove 520. Therefore, the number of vents 530 is half of the number of oil return grooves 520 on the left and right end faces of the oil slinger structure 500, which is 2N. That is, the number of vents 530 = N. The vents 530 are also arranged periodically. The product of the included angle β between two adjacent vents 530 and the number of vents 530 is 360, that is, β*N = 360.

[0125] In a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the diameter of the vent hole 530 is 1mm to 3mm.

[0126] Each vent hole has the same diameter (530), but none should be too large. It is recommended to be between 1mm and 3mm, because an excessively large diameter may cause more lubricating oil to penetrate, affecting the efficiency of oil removal.

[0127] like Figure 9A As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the vent 530 is positioned higher than the inlet end face of the plunger tube 200.

[0128] The aforementioned vent 530 is restricted in its radial position; the radial position of the vent 530 cannot be lower than the plunger tube inlet end face 210, i.e. Figure 9B As shown, otherwise the air flowing out of the vent 530 will be blocked by the radial end face 110 of the fan shaft, which is not conducive to ventilation.

[0129] like Figures 10A to 10DAs shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the central axes of the oil-throwing discs at each stage coincide.

[0130] Taking the oil-slinging structure 500, which includes a three-stage oil-slinging plate 510c, as an example, the second-stage oil-slinging plate 510b is arranged with oil return grooves 520 and ventilation holes on its circumference, following the same arrangement as the first-stage oil-slinging plate 510a. The number of oil return grooves 520 and ventilation holes is also consistent with that of the first-stage oil-slinging structure 500. The arrangement of the oil return grooves 520 and ventilation holes on the third-stage oil-slinging plate 510c is consistent with that on the first-stage oil-slinging plate 510a.

[0131] The oil-slinging structure 500, composed of three-stage oil-slinging discs 510c, is aligned along the central axis. This allows the oil-slinging structure 500 to be better stretched out under centrifugal force, and also facilitates processing.

[0132] like Figures 10A to 10D As shown, in a preferred embodiment of the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention, the width of each oil-throwing disc decreases progressively.

[0133] In the oil slinger structure 500, the width of each oil slinger disc decreases progressively; that is, the higher the number of oil slinger discs, the smaller their width. Taking the oil slinger structure 500 containing a three-stage oil slinger disc 510c as an example, the width of the three-stage oil slinger disc 510c is less than the width of the two-stage oil slinger disc 510b, which is less than the width of the first-stage oil slinger disc 510a. The maximum radial length of the entire oil slinger structure 500 is limited by the oil supply nozzle structure. To avoid interference, a safety distance of 1mm to 2mm must be maintained between the components of the oil supply nozzle.

[0134] like Figure 10C As shown, the width of the first-stage oil slinger 510a, which has the largest width, is also limited by the end faces of the steps on both sides, i.e., the values ​​of a and b marked in the figure. From a processing perspective, the distance between a and b should ideally have a margin of 3mm.

[0135] This invention focuses on improving the performance of centrifugal ventilators and reducing the overall lubricating oil consumption of engines. It improves and optimizes the structure of the fan shaft 100, a crucial rotating component in centrifugal ventilators, to enhance separation efficiency, reduce lubricating oil consumption, promote ventilation and oil return in the entire engine lubricating oil system, and increase the engine's continuous operating time.

[0136] In summary, the stretchable multi-segment axial fan shaft oil-throwing structure of the present invention has the following advantages:

[0137] First, breaking through the traditional structure of the aero-engine fan shaft 100, a completely new form of fan shaft 100 structure is proposed, opening up new ideas for the design of the entire lubrication system of aero-engines.

[0138] Second, an oil-slinging structure 500 is provided on the fan shaft 100 to better promote the separation of lubricating oil from the oil-gas mixture and promote ventilation and oil return.

[0139] Third, the oil slinger structure 500 on the fan shaft 100 is a stretchable multi-segment structure with a novel structure that can match ventilation oil return at different speed ranges.

[0140] Fourth, because oil return grooves 520 and ventilation holes are opened on the surface of each section of the oil-slinging structure 500, the structure of the oil-slinging structure 500 can both sling oil and provide ventilation.

[0141] Fifth, it can further improve the performance of the centrifugal ventilator on the original basis, increase the oil return capacity, reduce the lubricating oil consumption, especially the lubricating oil of the main shaft bearing in the front bearing cavity, while not affecting the ventilation function of the centrifugal ventilator.

[0142] This invention has broad application value and can be applied to the design of ventilation and oil return structures for lubrication systems in military and civilian aircraft engines, ground gas turbines, or gas generators.

[0143] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A stretchable multi-segment axial fan shaft oil-throwing structure, characterized in that, The oil-throwing structure is annular and is arranged around the outside of the fan shaft of the centrifugal ventilator, located between the plunger tube and the first bearing of the centrifugal ventilator. The oil-throwing structure can extend and retract in the radial direction of the fan shaft. The oil-throwing structure includes at least two stages of oil-throwing discs. The first stage oil-throwing disc is fixedly disposed on the outside of the fan shaft, and the second stage oil-throwing disc is movably connected to the outside of the first stage oil-throwing disc. Under centrifugal force, the second stage oil-throwing disc can extend outward in the radial direction of the fan shaft.

2. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 1, characterized in that, Each stage of the oil-throwing disc has multiple oil return grooves arranged in the radial direction, and each oil return groove penetrates the radial upper surface and the bottom reference surface of each stage of the oil-throwing disc.

3. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, The oil-throwing structure includes three-stage oil-throwing discs. The first-stage oil-throwing disc is fixedly installed on the outside of the fan shaft. The second-stage oil-throwing disc is movably connected to the outside of the first-stage oil-throwing disc. The third-stage oil-throwing disc is movably connected to the outside of the second-stage oil-throwing disc. Under the action of centrifugal force, the second-stage oil-throwing disc and the third-stage oil-throwing disc can extend outward in the radial direction of the fan shaft.

4. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 1, characterized in that, The oil-slinging structure is integrally connected to the fan shaft.

5. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, The oil return groove has a rotation direction, and the rotation direction of the oil return groove is consistent with the rotation direction of the fan shaft.

6. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 5, characterized in that, The direction of rotation, included angle, and width of each of the oil return grooves are the same.

7. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, Multiple oil return grooves are simultaneously provided on the left and right end faces of each stage of the oil slinger. The number of oil return grooves on the left and right end faces is the same, and they are arranged symmetrically.

8. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 7, characterized in that, The depth of the oil return groove is 1mm to 2mm.

9. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, The oil return grooves on the secondary oil slinger are interspersed with the oil return grooves on the primary oil slinger.

10. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 3, characterized in that, The oil return grooves on the third-stage oil slinger and the second-stage oil slinger are interspersed.

11. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, On each of the oil-slinging discs, there is a vent hole between every two adjacent oil return grooves.

12. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 11, characterized in that, The diameter of the vent hole is 1mm to 3mm.

13. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 11, characterized in that, The vent is positioned higher than the inlet end face of the plunger tube.

14. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, The central axes of the oil-slinging discs at each level coincide.

15. The stretchable multi-segment axial fan shaft oil-throwing structure as described in claim 2, characterized in that, The width of the oil-slinging discs decreases progressively with each level.

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