Stretchable multi-section type axis fan shaft oil throwing structure

Abstract

The invention provides a stretchable multi-section type axis fan shaft oil throwing structure which is in a circular ring shape, arranged on the outer side of a fan shaft of a centrifugal ventilator in a surrounding mode and located between a plunger pipe and a first bearing of the centrifugal ventilator, and the oil throwing structure can stretch out and draw back in the radial direction of the fan shaft. The oil throwing structure comprises at least two stages of oil throwing discs, the first-stage oil throwing disc is fixedly arranged on the outer side of the fan shaft, the second-stage oil throwing disc is movably connected to the outer side of the first-stage oil throwing disc, and under the centrifugal effect, the second-stage oil throwing disc can extend outwards in the radial direction of the fan shaft. According to the oil slinging structure, lubricating oil can be better promoted to be separated from an oil-gas mixture, ventilation oil return is promoted, and the oil slinging structure is of a stretchable multi-section structure, is novel in structural form and can be matched with ventilation oil return under different rotating speed sections.

Description

Technical Field

[0001] The invention relates to the technical field of bearing cavity ventilation and oil return, and in particular to a stretchable multi-section axial fan shaft oil throwing structure. Background Art

[0002] The power of aircraft engine transmission mainly comes from the gas working on the turbine, and the hot air from the combustion chamber rotates the main shaft and drives other accessories. These mechanical transmissions require a lubrication system to ensure their reliability. During the transmission process, the main bearing sealing system of the aircraft engine needs to be sealed with air at a certain pressure. Some of the air involved in the seal will enter the bearing cavity, where the air and lubricating oil are mixed to form an oil-gas mixture. If the oil and gas are directly discharged from the bearing cavity, a large amount of lubricating oil will be lost. The reserve amount of aircraft engine lubricating oil is certain, and a large amount of lubricating oil consumption will inevitably affect the mechanical performance of the engine, thereby affecting other major performances of the engine.

[0003] Therefore, a ventilator is set on the ventilation path between the bearing cavity and the outside world to separate the lubricating oil in the air to reduce the lubricating oil consumption. Typical ventilators include centrifugal ventilators, impeller ventilators and axial ventilators.

[0004] For large civil aircraft engines, the engine power is large and the heat generated is high. Compared with small engines for military aircraft, large engines for civil aircraft require more lubricating oil to lubricate and cool the optional structure. Therefore, a more efficient ventilator structure is needed to separate the lubricating oil to reduce the lubricating oil consumption rate.

[0005] The more mature ventilator structure now is the plunger tube type axial ventilator, which is mainly composed of multiple plunger tubes and fan shafts, and each plunger tube is installed on the through hole of the fan shaft. When the oil-gas mixture enters the plunger tube, the lubricating oil flows out from the oil return groove on the plunger tube under the action of centrifugal force, and is thus separated, while the gas has a smaller density and inertia, and is discharged from the central channel of the fan shaft, thus completing the ventilation and oil return of the entire system.

[0006] As a relatively mature aircraft engine centrifugal ventilator structure, the axial ventilator is installed on the low-pressure shaft of the engine. Centrifugal ventilators of this structural form have been widely used in multiple models, and the structure is relatively mature. However, during the actual whole machine test, it was still found that there was obvious white mist at the center tail of the engine, and the centrifugal ventilator's ability to separate lubricating oil has room for improvement. Based on this point, the present invention makes some improvements and optimizations to the fan shaft structure that drives the entire centrifugal ventilator, so as to better improve the separation efficiency of the centrifugal ventilator.

[0007] In view of this, the inventor of the present application has designed a stretchable multi-stage axial fan shaft oil-spraying 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 defect of insufficient lubricating oil separation capacity of the centrifugal ventilator in the prior art and to provide a stretchable multi-stage axial fan shaft oil throwing structure.

[0009] The present invention solves the above technical problems through the following technical solutions:

[0010] The present invention provides a stretchable multi-section axial fan shaft oil-flinging structure, which is characterized in that the oil-flinging structure is annular, arranged around the outside of the fan shaft of a centrifugal ventilator, and located between the plunger tube and the first bearing of the centrifugal ventilator. The oil-flinging structure can be extended and retracted in the radial direction of the fan shaft; the oil-flinging structure includes at least two stages of oil-flinging plates, the first stage of the oil-flinging plate is fixedly arranged on the outside of the fan shaft, and the second stage of the oil-flinging plate is movably connected to the outside of the first stage of the oil-flinging plate. Under the action of centrifugation, the second stage of the oil-flinging plate can stretch outward in the radial direction of the fan shaft.

[0011] According to an embodiment of the present invention, a plurality of oil return grooves are arranged on each stage of the oil slinger plate in the radial direction, and each of the oil return grooves penetrates the radial upper surface and the bottom reference surface of each stage of the oil slinger plate.

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

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

[0014] According to an 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 an embodiment of the present invention, the rotation direction, 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 the oil return grooves are simultaneously arranged on the left end face and the right end face of each stage of the oil throwing plate, and the number of the oil return grooves on the left end face and the right end face is the same and they are arranged symmetrically.

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

[0018] According to an embodiment of the present invention, the oil return grooves on the secondary oil-spinning plate and the oil return grooves on the primary oil-spinning plate are arranged alternately.

[0019] According to an embodiment of the present invention, the oil return grooves on the third-stage oil-spinning plate and the oil return grooves on the second-stage oil-spinning plate are staggered with each other.

[0020] According to an embodiment of the present invention, a vent hole is provided between every two adjacent oil return grooves on each stage of the oil-slinging plate.

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

[0022] According to an embodiment of the present invention, the vent hole is disposed at a position higher than an inlet end surface of the plunger tube.

[0023] According to an embodiment of the present invention, the central axes of the oil-slinging pans at each stage coincide with each other.

[0024] According to an embodiment of the present invention, the width of each level of the oil-slinging pan decreases step by step.

[0025] The positive and progressive effects of the present invention are:

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

[0027] 1. Breaking through the traditional aircraft engine fan shaft structure, a new form of fan shaft structure is proposed, which opens up new ideas for the design of the entire lubricating oil system of the aircraft engine.

[0028] 2. An oil-throwing structure is set on the fan shaft to better separate the lubricating oil from the oil-gas mixture and promote ventilation and oil return.

[0029] 3. Since the oil-throwing structure on the fan shaft is a stretchable multi-section structure, its structural form is novel and can match the ventilation and oil return at different speed sections.

[0030] Fourth, since the oil return grooves and ventilation holes are opened on the surface of each section of the oil-slinging structure, the oil-slinging structure can not only throw oil but also achieve ventilation effect.

[0031] 5. The performance of the centrifugal ventilator can be further improved on the original basis, the oil return capacity is increased, and the lubricating oil consumption is reduced, especially the lubricating oil of the main shaft bearing in the front bearing cavity, while the ventilation function of the centrifugal ventilator is not affected. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0033] Figure 1A It is a schematic diagram of the working principle of the centrifugal ventilator in the prior art.

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

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

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

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

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

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

[0040] Figure 4A It is a schematic diagram of the structural relationship between the stretchable multi-section 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 of FIG.

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

[0043] Figure 5B yes Figure 5A An enlarged schematic diagram of part D of FIG.

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

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

[0046] Fig. 6A It is a front view schematic diagram of the layout of the oil return groove of the stretchable multi-section axial fan shaft oil-swing structure on the oil-swing structure of the present invention.

[0047] Figure 6B It is a front-view stereoscopic schematic diagram of the layout of the oil return groove of the stretchable multi-section axial fan shaft oil-swing structure on the oil-swing structure of the present invention.

[0048] Figure 6C It is a rear-view stereoscopic schematic diagram of the layout of the oil return groove of the stretchable multi-section axial fan shaft oil-swing structure on the oil-swing structure of the present invention.

[0049] Fig. 7A It is a schematic diagram of the positional relationship between the end surfaces on both sides of the oil-throwing structure of the oil-throwing structure of the stretchable multi-section axial fan of the present invention.

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

[0051] Fig. 8A It is the first stereoscopic schematic diagram of the positional relationship between the ventilation holes of the stretchable multi-section axial fan shaft oil-flinging structure of the present invention and the end surfaces on both sides of the oil-flinging structure.

[0052] Figure 8B It is a second stereoscopic schematic diagram of the positional relationship between the ventilation holes of the stretchable multi-section axial fan shaft oil-flinging structure of the present invention and the end surfaces on both sides of the oil-flinging structure.

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

[0054] Fig.8D It is a front view schematic diagram of the positional relationship between the ventilation holes of the stretchable multi-section axial fan shaft oil-fling structure of the present invention and the end surfaces on both sides of the oil-fling structure.

[0055] Fig. 9A It is a schematic diagram showing that the ventilation holes of the stretchable multi-section axial fan shaft oil-throwing structure of the present invention are located radially higher than the inlet end face of the plunger tube.

[0056] Fig. 9B It is a schematic diagram showing that the ventilation holes of the stretchable multi-section axial fan shaft oil-throwing structure of the present invention are located radially lower than the inlet end face of the plunger tube.

[0057] Fig. 10A It is the first partial cross-sectional schematic diagram of the complete structure of the stretchable multi-section axial fan shaft oil-throwing structure of the present invention.

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

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

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

[0061] [Reference Signs]

[0062] Fan shaft 100

[0063] Fan shaft radial end face 110

[0064] Plunger tube 200

[0065] Plunger tube inlet end face 210

[0066] First bearing 300

[0067] Oil return port 400

[0068] Oil throwing structure 500

[0069] First-stage oil-spinning plate 510a

[0070] Secondary oil thrower 510b

[0071] Three-stage oil thrower 510c

[0072] Oil return tank 520

[0073] Ventilation hole 530

[0074] Radial upper surface 540

[0075] Bottom reference surface 550

[0076] Second bearing 600

[0077] Rear vent 700

[0078] Front vent 800

[0079] Oil supply pipe 900

[0080] Lubricating oil nozzle 1000

[0081] Nozzle 1100 DETAILED DESCRIPTION

[0082] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0083] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Reference will now be made in detail to preferred embodiments of the present invention, examples of which are shown in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to represent the same or similar parts.

[0084] Furthermore, although the terms used in the present invention are selected from well-known and commonly used terms, some terms mentioned in the present invention specification may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this document.

[0085] Furthermore, it is required that the present invention be understood not only by the actual terms used but also by the meanings connoted by each term.

[0086] Figure 1A and Figure 1B The working principle of the centrifugal ventilator is shown. The centrifugal ventilator is mainly composed of two parts: the fan shaft 100 and a plurality of plunger tubes 200. After the oil-gas mixture passes through the plunger tube 200, the lubricating oil is separated and flows out from the oil return port 400 under the centrifugal force generated by the high-speed rotation of the fan shaft 100, and 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 oil return.

[0087] As for the source of the oil-air mixture, the air mainly comes from two places, namely the front vent hole 800 and the rear vent hole 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] Take the case where the first bearing 300 is a rod bearing and the second bearing 600 is a ball bearing as an example: the ball bearing as the second bearing 600 adopts the method of under-ring oil supply and is far away from the entrance of the plunger tube 200. Under the centrifugal force of the fan shaft 100, most of the lubricating oil from the ball bearing can enter the oil return port 400 and return smoothly. The lubricating oil flowing out of the rod bearing as the first bearing 300 is close 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 of the rod bearing as the first bearing 300 is provided by the oil supply pipe 900. Under the action of pressure, the lubricating oil flows from the oil supply pipe 900, enters the lubricating oil nozzle 1000, and finally sprays out from the spray hole 1100. This is a typical jet lubrication method to provide lubrication for the rod bearing, so some lubricating oil will flow out of the rod bearing and enter the centrifugal ventilator. The ventilator needs to be used for oil return, and finally flows out from the oil return port 400. Because the distance between the lubricating oil from the rod bearing and the plunger tube 200 is relatively close, there will be a situation where a lot of lubricating oil flows into the plunger tube 200 in a short time, resulting in a part of the lubricating oil being unable to be separated. With the airflow, it flows out from the central channel of the fan shaft 100, which has the risk of increasing the lubricating oil consumption.

[0090] In view of the above risks, the present invention improves the structure of the fan shaft 100. An oil-flinging structure 500 is added to the original fan shaft 100 to block the lubricating oil flowing out of the rod bearing serving as the first bearing 300. The lubricating oil flowing out of the rod bearing does not directly enter the plunger tube 200, but bypasses the oil-flinging structure 500 and is thrown onto the wall of the bearing cavity through the oil-flinging structure 500. The lubricating oil flows out from the return oil under the influence of gravity and the suction of the return oil pump, thereby achieving the effect of oil return.

[0091] like Figure 2A to Figure 2B , Figure 3A to Figure 3C As shown, the present invention discloses a stretchable multi-section axial fan shaft oil-flinging structure, the oil-flinging structure 500 is annular, and is arranged around the outside of the fan shaft 100 of the centrifugal ventilator, and is located between the plunger tube 200 and the first bearing 300 of the centrifugal ventilator. The oil-flinging structure 500 can be extended and retracted in the radial direction of the fan shaft 100.

[0092] The oil-spinning structure 500 includes at least two stages of oil-spinning plates, wherein the first stage oil-spinning plate 510a is fixedly arranged on the outside of the fan shaft 100, and the second stage oil-spinning plate 510b is movably connected to the outside of the first stage oil-spinning plate 510a. Under the action of centrifugation, the second stage oil-spinning plate 510b can extend outward in the radial direction of the fan shaft 100.

[0093] The oil-slinging structure 500 will be stretched to form different states under the centrifugal force generated by the rotation of the fan shaft 100. Therefore, at different rotation speeds, the state of the oil-slinging structure 500 will be different. When the oil-slinging structure 500 is stretched to the limit, the surface area of ​​the oil-slinging structure 500 is the largest and its oil-slinging ability is the strongest. At the same time, under the condition of high rotation speed, the oil supply amount of the lubricating oil is large, and the amount of lubricating oil leaking from the rod bearing as the first bearing 300 is also more. The state of the oil-slinging structure 500 that matches it is needed to sling the lubricating oil, so as to better perform oil return and ventilation.

[0094] Since the oil-swinging structure 500 of the present invention is arranged on the fan shaft 100 and is 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-air mixture and promote ventilation and oil return.

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

[0096] The setting of the oil-swinging 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 do not affect the ventilation function of the centrifugal ventilator.

[0097] like Figure 5A to Figure 5D As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-flinging structure of the present invention, a plurality of oil return grooves 520 are arranged along the radial direction on each stage of the oil-flinging plate, and each oil return groove 520 passes through the radial upper surface 540 and the bottom reference surface 550 of each stage of the oil-flinging plate.

[0098] The oil-swinging structure 500 in the above embodiment is different from the oil-swinging structure 500 in the prior art in that a plurality of oil return grooves 520 are provided on the oil-swinging structure 500, which can increase the flow area of ​​the lubricating oil on the oil-swinging structure 500. The purpose of such design is to enable better oil return.

[0099] like Figure 5A and Figure 5B As shown, it is a schematic diagram of the structural relationship between the oil return groove 520 provided on the oil-slinging structure 500 and the fan shaft 100. The oil return groove 520 must maintain a through-state 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-slinging plate 510a (i.e., the radial upper surface 540 of the oil-slinging plate), and there must be no gap between the two.

[0100] like Figure 5C and Figure 5D As shown, it is an explanation for the above-mentioned gap that cannot exist. It can be seen that there is a certain small gap H between the return oil groove 520 and the outer surface of the first-stage oil-slinging plate 510a. This is an unacceptable structure because it will cause the lubricating oil to accumulate on one side of the return oil groove 520, which is not conducive to the oil-slinging structure 500 to throw oil.

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

[0102] like Figure 3A to Figure 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. As the rotation speed of the fan shaft 100 changes, the state of the oil-slinging structure 500 will also be different.

[0103] According to the running state of the engine, the centrifugal ventilator is on the low-pressure shaft, that is, the main shaft with a relatively low speed. According to all working conditions of the whole machine test, the speed range of the centrifugal ventilator is between 800 and 4000rpm, and as the speed increases, the oil supply of the lubricating oil nozzle 1000 will also increase. According to the test results, it can be guided that the oil supply of the lubricating oil nozzle 1000 is proportional to the speed.

[0104] The oil-slinging structure 500 in the above-mentioned embodiment will be stretched into three different states under the centrifugal force generated by the rotation of the fan shaft 100. The one-stage state corresponds to a rotation speed between 800 and 1300 rpm, the two-stage state corresponds to a rotation speed between 1300 and 1800 rpm, and the three-stage state corresponds to a rotation speed between 1800 and 3000 rpm. At different rotation speeds, the state of the oil-slinging structure 500 will be different. When the oil is slinging in the three-stage state, the surface area of ​​the oil-slinging structure 500 is the largest and the oil-slinging ability is the strongest. At the same time, under the condition of a higher rotation speed, the oil supply of the lubricating oil is larger, and the amount of lubricating oil leaking from the rod bearing is also more. The oil-slinging structure 500 state that matches it is required to sling the lubricating oil, so as to better perform oil return and ventilation.

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

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

[0107] like Figure 6A to Figure 6C As shown, as a preferred embodiment of the stretchable multi-stage 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 rotation direction and is not a straight-through structure. Figure 6A to Figure 6C As shown, its rotation direction is consistent with the rotation direction E of the fan shaft 100. Figure 6B The figure shows the rotation direction of the fan shaft 100 when the engine is running normally. Therefore, the rotation direction of all the oil return grooves 520 on the oil throwing structure 500 is consistent with the rotation direction E of the fan shaft 100. Figure 6C As shown, the rotation direction of the oil return groove 520 is counterclockwise.

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

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

[0111] The structures of all the oil return grooves 520 on the oil-swinging structure 500 in the above-mentioned embodiment are the same, that is, the rotation direction, angle and width of the oil return grooves 520 are consistent, which can facilitate manufacturing and processing.

[0112] The number N of all the oil return grooves 520 of the oil-slinging structure 500 of the present invention is determined by structural CAE finite element strength analysis and calculation. The greater the number N of the oil return grooves 520, the greater the flow area of ​​the lubricating oil will be, but at the same time, the strength of the oil-slinging structure 500 will be reduced. Therefore, it is necessary to determine the optimal value of the number N of the oil return grooves 520 through CAE finite element analysis.

[0113] like Fig. 7A and Figure 7BAs shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-flinging structure of the present invention, a plurality of oil return grooves 520 are simultaneously arranged on the left end face and the right end face of each stage of the oil-flinging plate, and the number of the oil return grooves 520 located on the left end face and the right end face is the same and they are symmetrically arranged.

[0114] The oil return grooves 520 in the above embodiment are provided on both the left and right end faces of the oil-slinging structure 500, and the number of the oil return grooves 520 on the two end faces is required to be the same, and they are arranged symmetrically. Therefore, when checking the strength of the oil-slinging structure 500 by CAE finite element method, the oil return grooves 520 on both end faces need to be considered.

[0115] like Figure 7B As shown, the oil return grooves 520 in the above embodiment are arranged in a symmetrical form on the two end surfaces of the oil-swinging structure 500. The oil return grooves 520 on both sides cannot penetrate each other. There are certain restrictions on the depth of the oil return grooves 520, but the depths of the oil return grooves 520 on both sides must remain consistent, that is, m=n.

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

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

[0118] like FIG. 10A to FIG. 10D As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-spinning structure of the present invention, the oil return groove 520 on the secondary oil-spinning plate 510b and the oil return groove 520 on the primary oil-spinning plate 510a are staggered with each other.

[0119] like FIG. 10A to FIG. 10D As shown in FIG. 5 , the complete structure of the oil-spinning structure 500 in the above embodiment is shown. Fig. 10B As shown, the distribution of the oil return grooves 520 on the secondary oil slinger plate 510b is staggered from the oil return grooves 520 on the primary oil slinger plate 510a to ensure that the lubricated oil can flow out from more paths rather than staying in the oil return grooves 520 of one path.

[0120] like FIG. 10A to FIG. 10D As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-spinning structure of the present invention, the oil return groove 520 on the third-stage oil-spinning plate 510c and the oil return groove 520 on the second-stage oil-spinning plate 510b are staggered with each other.

[0121] like Fig. 10BAs shown, the distribution of the oil return grooves 520 on the tertiary oil slinger plate 510c and the oil return grooves 520 on the secondary oil slinger plate 510b are staggered to ensure that the lubricated oil can flow out from more paths rather than staying in the oil return grooves 520 of one path.

[0122] like Figures 8A to 8D As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-spinning structure of the present invention, a vent hole 530 is provided between every two adjacent oil return grooves 520 on each stage of the oil-spinning plate.

[0123] like Figures 8A to 8D As shown, the oil-slinging structure 500 in the above embodiment may also have an air vent 530 in the middle of the adjacent oil-slinging grooves 520 while providing the oil return grooves 520. The purpose of providing the air vent 530 is to enable ventilation. Because the lubricating oil flowing out of the rod bearing as the first bearing 300 is mixed with air, if the air vent 530 is not provided on the oil-slinging structure 500, it will cause poor flow in the local area, which is not conducive to ventilation.

[0124] like Fig.8D As shown, the air holes 530 in the above embodiment are arranged in the middle position of adjacent oil return grooves 520, so the number of the air holes 530 is half of the number 2N of the oil return grooves 520 on the left and right end surfaces of the oil-slinging structure 500, that is, the number of the air holes 530 = N, and the air holes 530 are also arranged periodically, and the product of the angle β between two adjacent air holes 530 and the number of the air holes 530 is 360, that is, β*N=360.

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

[0126] The diameter of each vent hole 530 is the same, but should not be too large. It is recommended that the diameter be between 1 mm and 3 mm, because a too large diameter may cause more lubricating oil to penetrate, affecting the efficiency of oil throwing.

[0127] like Fig. 9A As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-throwing structure of the present invention, the vent hole 530 is set at a position higher than the inlet end face of the plunger tube 200.

[0128] The vent hole 530 has a limitation in radial position, and the radial position of the vent hole 530 cannot be lower than the inlet end face 210 of the plunger tube, that is, Fig. 9B Otherwise, the air flowing out of the vent hole 530 will be blocked by the radial end surface 110 of the fan shaft, which is not conducive to ventilation.

[0129] like FIG. 10A to FIG. 10DAs shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-spinning structure of the present invention, the central axes of the oil-spinning plates at each stage coincide.

[0130] Taking the oil-spinning structure 500 including the three-stage oil-spinning plate 510c as an example, the oil-returning grooves 520 and ventilation holes are arranged on the circumference of the second-stage oil-spinning plate 510b in the same manner as the first-stage oil-spinning plate 510a. The number of the oil-returning grooves 520 and ventilation holes is also consistent with that of the first-stage oil-spinning structure 500. The arrangement of the oil-returning grooves 520 and ventilation holes on the three-stage oil-spinning plate 510c is consistent with that on the first-stage oil-spinning plate 510a.

[0131] The oil-spinning structure 500 composed of three-stage oil-spinning plates 510c is aligned along the central axis, so that the oil-spinning structure 500 can be better stretched out under the action of centrifugal force and is also convenient for processing.

[0132] like FIG. 10A to FIG. 10D As shown, as a preferred embodiment of the stretchable multi-stage axial fan shaft oil-spinning structure of the present invention, the width of the oil-spinning plate at each stage decreases step by step.

[0133] The width of each oil-slinging plate in the oil-slinging structure 500 is gradually reduced, that is, the higher the number of oil-slinging plates, the smaller the width of the oil-slinging plates. Taking the oil-slinging structure 500 including the three-stage oil-slinging plate 510c as an example, the width of the three-stage oil-slinging plate 510c is less than the width of the two-stage oil-slinging plate 510b and less than the width of the first-stage oil-slinging plate 510a. The maximum radial length of the entire oil-slinging structure 500 is limited by the oil supply nozzle structure. In order to avoid interference, a safety distance of 1mm to 2mm is required between the components of the oil supply nozzle.

[0134] like Fig. 10C As shown, the width of the first-stage oil-slinging plate 510a with the largest width is also limited by the step end surfaces on both sides, that is, the values ​​of a and b marked in the figure. From a processing perspective, the distance between a and b should preferably have a margin of 3 mm.

[0135] The present invention improves and optimizes the structure of the fan shaft 100, an important rotating component in the centrifugal ventilator, from the perspective of improving the performance of the centrifugal ventilator and reducing the lubricating oil consumption of the entire engine, so as to improve the separation efficiency, reduce the lubricating oil consumption, promote ventilation and oil return of the entire engine lubricating oil system, and increase the continuous endurance time of the engine.

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

[0137] 1. Breaking through the traditional structural form of the aircraft engine fan shaft 100, a new form of fan shaft 100 structure is proposed, which opens up new ideas for the design of the entire lubricating oil system of the aircraft engine.

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

[0139] 3. Since the oil-swinging structure 500 on the fan shaft 100 is a stretchable multi-section structure, its structural form is novel and can match the ventilation and oil return at different speed sections.

[0140] Fourth, since the oil return groove 520 and the ventilation holes are provided on the surface of each section of the oil-slinging structure 500, the oil-slinging structure 500 can not only spin the oil but also achieve the effect of ventilation.

[0141] 5. The performance of the centrifugal ventilator can be further improved on the original basis, the oil return capacity is increased, and the lubricating oil consumption is reduced, especially the lubricating oil of the main shaft bearing in the front bearing cavity, while the ventilation function of the centrifugal ventilator is not affected.

[0142] The invention has wide popularization and application value and can be applied to the ventilation and oil return structure design of the lubricating oil system of military and civil aviation engines, ground combustion engines or gas generators.

[0143] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A stretchable multi-stage axial fan shaft oil-swinging structure, characterized in that: The oil-slinging structure is annular, arranged around the outside of the fan shaft of the centrifugal ventilator, and located between the plunger tube and the first bearing of the centrifugal ventilator. The oil-slinging structure can be extended and retracted in the radial direction of the fan shaft. The oil-slinging structure includes at least two stages of oil-slinging plates, wherein the first stage oil-slinging plate is fixedly arranged on the outside of the fan shaft, and the second stage oil-slinging plate is movably connected to the outside of the first stage oil-slinging plate. Under the centrifugal action, the second stage oil-slinging plate can extend outward in the radial direction of the fan shaft.

2. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 1, characterized in that: A plurality of oil return grooves are arranged on each stage of the oil throwing plate in the radial direction, and each of the oil return grooves passes through the radial upper surface and the bottom reference surface of each stage of the oil throwing plate.

3. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: The oil-slinging structure includes a three-stage oil-slinging plate, wherein the first-stage oil-slinging plate is fixedly arranged on the outside of the fan shaft, the second-stage oil-slinging plate is movably connected to the outside of the first-stage oil-slinging plate, and the third-stage oil-slinging plate is movably connected to the outside of the second-stage oil-slinging plate. Under the action of centrifugal force, the second-stage oil-slinging plate and the third-stage oil-slinging plate can extend outward in the radial direction of the fan shaft.

4. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 1, characterized in that: The oil-swinging structure is integrally connected to the fan shaft.

5. The stretchable multi-stage axial fan shaft oil-swinging structure according to 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-stage axial fan shaft oil-swinging structure according to claim 5, characterized in that: The rotation direction, angle and width of each oil return groove are the same.

7. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: A plurality of the oil return grooves are simultaneously arranged on the left end surface and the right end surface of each stage of the oil throwing plate, and the number of the oil return grooves on the left end surface and the right end surface is the same and they are symmetrically arranged.

8. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 7, characterized in that: The depth of the oil return groove is 1 mm to 2 mm.

9. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: The oil return grooves on the secondary oil-spinning plate and the oil return grooves on the primary oil-spinning plate are arranged alternately with each other.

10. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 3, characterized in that: The oil return grooves on the third-stage oil-spinning plate and the oil return grooves on the second-stage oil-spinning plate are arranged alternately.

11. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: On each level of the oil-slinging plate, a vent hole is provided between every two adjacent oil return grooves.

12. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 11, characterized in that: The diameter of the vent hole is 1 mm to 3 mm.

13. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 11, characterized in that: The vent hole is arranged at a position higher than the inlet end surface of the plunger tube.

14. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: The central axes of the oil-slinging plates at each level coincide with each other.

15. The stretchable multi-stage axial fan shaft oil-swinging structure according to claim 2, characterized in that: The width of the oil-slinging pan at each level decreases step by step.

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