CN117803697A - Helicopter rotor taper transmission shaft and manufacturing method thereof - Google Patents

Abstract

The invention relates to the technical field of helicopter transmission shafts and discloses a helicopter rotor taper transmission shaft and a manufacturing method thereof, wherein the helicopter rotor taper transmission shaft comprises a taper shaft, a first flange seat arranged at one end of the taper shaft rod and a second flange seat arranged at the other end of the taper shaft rod, the taper shaft is integrally assembled with a high-speed engine driving shaft through the first flange seat, the taper shaft is integrally assembled with a rotor through the second flange seat, and the taper angle of a taper shaft body is 3 degrees. The invention is based on the transmission shaft in the existing straight rod form, by arranging the taper transmission shaft, the gravity center can be controlled to be at the shaft taper big end when the transmission shaft transmits large torque and ultrahigh rotating speed, the gravity center deflection can be controlled through root restriction when the transmission shaft rotates at high speed, and when the taper transmission shaft transmits large torque and ultrahigh rotating speed, the taper transmission shaft can improve 10% transmission efficiency compared with the traditional shaft under the same working condition because the shaft is shaped as a taper belt angle compared with the traditional shaft.

Description

A helicopter rotor taper transmission shaft and its manufacturing method

Technical field

The invention relates to the technical field of helicopter transmission shafts, specifically a helicopter rotor taper transmission shaft and a manufacturing method thereof.

Background technique

The helicopter rotor drive shaft is an important structural component of the helicopter. It is located between the high-speed drive shaft and the rotor. Its function is to transmit the output power of the high-speed drive shaft to the rotor and drive the propeller to rotate. Therefore, the drive shaft carries large torque and super speed. For high-speed transmission, most of the existing traditional transmission shafts are in the form of straight rods. When transmitting large torque and ultra-high speed, there will be disturbances in the middle of the shaft. Especially at high speeds, the middle of the shaft will swing outward, causing vibration and causing no problems. It is beneficial to the mechanical ratio transmission of the transmission shaft. Therefore, those skilled in the art provide a helicopter rotor taper transmission shaft and a manufacturing method thereof to solve the problems raised in the above background art.

Contents of the invention

The object of the present invention is to provide a helicopter rotor taper transmission shaft and a manufacturing method thereof to solve the problems raised in the above background technology.

In order to achieve the above object, the present invention provides the following technical solution: a helicopter rotor taper transmission shaft, including a taper shaft, a first flange seat installed on one end of the taper shaft shaft, and a second flange seat installed on the other end of the taper shaft shaft. The flange seat, the taper shaft is integrally assembled with the high-speed engine drive shaft through the first flange seat, and the taper shaft is integrally assembled with the rotor through the second flange seat, wherein:

The taper shaft includes a taper shaft body. One end of the shaft of the taper shaft body is provided with a first spline tooth groove, and the other end of the shaft rod of the taper shaft body is provided with a second spline tooth groove. The taper shaft body The taper angle is 3°.

The first flange seat includes a first flange plate, and a first coupling spline shaft corresponding to the first spline tooth groove is provided on one side of the central axis of the plate body of the first flange plate, and a third The other side of the central axis of a flange plate is provided with a first assembly spline shaft that is adapted to the high-speed engine drive shaft;

The second flange seat includes a second flange plate, and a second coupling spline shaft is provided on one side of the central axis of the plate body of the second flange plate to match the second spline tooth groove, and the third The other side of the central axis of the two flange plates is provided with a second assembly spline shaft that is adapted to the rotor.

As a further solution of the present invention: the spline length of the first coupled spline shaft is the same as the keyway length of the first spline tooth groove, and the distance between the first coupled spline shaft and the first spline tooth groove is Assembly and fixation through liquid nitrogen cold installation process.

As a further solution of the present invention: the spline length of the second pair of spline shafts is the same as the keyway length of the second spline tooth groove, and the second pair of spline shafts and the second spline tooth groove are assembled and fixed by a liquid nitrogen cold assembly process.

As a further solution of the present invention: a first gasket groove is provided on the side of the first flange plate close to the first assembly spline shaft, and the first gasket groove is lined with a first sealing gasket, so The first sealing gasket extends outward by 1 to 2 mm relative to the surface of the first flange.

As a further solution of the present invention: a second gasket groove is provided on the side of the second flange plate close to the second assembly spline shaft, and the interior of the second gasket groove is lined with a second sealing gasket, so The second sealing gasket extends outward by 1 to 2 mm relative to the surface of the second flange.

As a further solution of the present invention: the taper shaft is a truncated cone structure, and its taper calculation formula is: C=(D-d)/L;

Among them, C represents the taper ratio, D represents the diameter of the large end, d represents the diameter of the small end, and L represents the length of the cone.

A method for manufacturing a helicopter rotor tapered transmission shaft comprises the following steps:

Process 1: Forging blank,

(1) Preheating treatment: Before forging, the selected materials are subjected to low-temperature tempering treatment to improve the plasticity and toughness of the materials;

(2) Hot forging: placing the preheated material into the forging equipment for hot forging, changing the grain structure and shape of the material through thermal deformation to improve the material strength and plasticity;

(3) Cold extrusion, processed using cold extrusion technology to ensure its geometric dimensions and surface quality;

Step 2: Aging treatment, using quenching and tempering processes to improve the hardness and toughness of the material, and enhance its fatigue resistance and corrosion resistance;

Process 3: Rough turning of the outer circle, based on the CNC lathe method, using its rough turning tool to remove the excess material;

Process 4: Finishing the outer circle, based on the CNC lathe method, using its outer circle finishing tool to remove the small amount of margin left after rough turning on the material to meet the dimensional process specifications;

Process five: spline tooth opening, based on the form of CNC milling machine, using its milling cutter to process the corresponding spline shaft and spline tooth grooves on the finished material;

Step 6: Final inspection,

(1) Based on visual inspection, human observation is used to check the integrity of the surface processing of the processed material and the matching of the spline shaft and the spline tooth groove;

(2) Based on the measurement and testing method, whether the dimensional accuracy of the processed materials using measuring instruments reaches the standard;

(3) Based on mechanical testing methods, including but not limited to pushing, pulling or rotating methods, the bearing capacity of the processed material is tested to determine whether its mechanical properties meet the requirements.

As a further solution of the present invention: as the material in the first process, considering that the taper shaft often accelerates and rotates forward and reverse during the rotation process, and it often bears alternating loads and impact loads during the working process, it is selected Forgings are made so that the metal fibers are not cut. The forging dimensions are matched in advance according to the processing dimensions of the tapered shaft, and the material of the forgings is first titanium alloy or aluminum alloy.

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention is based on the existing transmission shaft in the form of a straight rod. By setting a tapered transmission shaft, the center of gravity can be controlled at the large end of the shaft taper when transmitting large torque and ultra-high speed. When the transmission shaft rotates at high speed, the center of gravity can be controlled by limiting the root. When the tapered transmission shaft is transmitting large torque and ultra-high speed, because the shape of the shaft is tapered and has an angle, compared with the traditional shaft under the same working conditions, the tapered transmission shaft can increase the transmission efficiency by 10% compared with the traditional shaft.

2. In the present invention, the tapered shaft, the first flange seat, and the second flange seat are independently processed and then integrated into a tapered transmission shaft. It has good disassembly processing performance, can reduce processing intensity and scrap costs, and improves Production efficiency of tapered drive shafts.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic structural diagram of a helicopter rotor taper transmission shaft;

Figure 2 is a schematic diagram of the unfolded structure of a helicopter rotor taper transmission shaft;

Figure 3 is a schematic structural diagram of a taper shaft in a helicopter rotor taper transmission shaft;

Figure 4 is a schematic structural diagram of the first flange seat in a helicopter rotor taper transmission shaft;

Figure 5 is a schematic structural diagram of a second flange seat in a helicopter rotor taper transmission shaft;

Figure 6 is a schematic assembly diagram of a helicopter rotor taper transmission shaft;

Figure 7 is a schematic diagram of the taper ratio of the taper shaft in a helicopter rotor taper drive shaft;

Figure 8 is a schematic diagram of the stress on the taper shaft in a helicopter rotor taper drive shaft;

Figure 9 is a schematic diagram of the force analysis of the taper shaft in a helicopter rotor taper drive shaft.

In the figure: 1. Taper shaft; 11. Taper shaft body; 12. First spline tooth groove; 13. Second spline tooth groove; 2. First flange seat; 21. First flange plate; 22. The first coupling spline shaft; 23. The first assembly spline shaft; 24. The first sealing gasket; 3. The second flange seat; 31. The second flange plate; 32. The second coupling spline shaft; 33. Second assembly spline shaft; 34. Second sealing gasket; 4. High-speed engine drive shaft; 5. Rotor.

Detailed ways

Please refer to Figures 1 to 9. In an embodiment of the present invention, a helicopter rotor taper transmission shaft includes a taper shaft 1, a first flange seat 2 installed on one end of the taper shaft 1 shaft, and a first flange seat 2 installed on the other end of the taper shaft 1 shaft. The second flange seat 3 at one end, the taper shaft 1 includes a taper shaft 11, the taper angle of the taper shaft 11 is 3°, the taper shaft 11 is a truncated cone structure, and the taper calculation formula is: C=(D-d) /L;

Among them, C represents the taper ratio, D represents the diameter of the large end, d represents the diameter of the small end, and L represents the length of the cone.

(As shown in Figures 8 and 9 of the manual), the forces on the tapered shaft 1 and the ordinary shaft are as follows:

According to the comparison calculation: the taper shaft mass M1 is equal to the ordinary shaft mass M2, that is, M1=M2;

The length of the tapered shaft 1 is L1, the length of the normal shaft is L2, and L1 = L2;

The center of gravity of the taper shaft 1 is at the thick end, and the center of gravity of the ordinary shaft is at the center of the shaft (as shown in Figure 8 of the instruction manual). The F pressure on the taper shaft 1 and the ordinary shaft are the same;

Calculation: M1=M2, L1=L2;

The taper axis 1 is calculated according to mechanical analysis (as shown in Figure 9 of the instruction manual): The resultant force formed by F pressure on the taper axis 1 is F2: F2 = F pressure cosinθ;

Conclusion: F2<F pressure, so the pressure at the stress point of taper axis 1 is F2;

Ordinary shafts are calculated according to mechanical analysis (as shown in Figure 9 of the instruction manual): The resultant force formed by F pressure on the shaft is F3 pressure: F3 pressure and F pressure coincide in the vertical direction, that is: F3=F pressure;

Conclusion: F3=F pressure, so the pressure at the force point of the common shaft is F pressure;

To summarize; the stress point of taper shaft 1 is F2 < F pressure, F pressure = F3, so F2 < F3, that is, compared with the ordinary shaft of the same size, the taper shaft 1 is subject to the same large pressure, and the rigidity of taper shaft 1 is more stable, and its rigidity is more stable at large. When transmitting torque and ultra-high speed, its taper ratio transmission method is compared with the traditional shaft. Under the same working conditions, the taper transmission shaft can increase the transmission efficiency by 10% compared with the traditional shaft.

One end of the shaft of the tapered shaft body 11 is provided with a first spline tooth groove 12, and the other end of the shaft of the tapered shaft body 11 is provided with a second spline tooth groove 13. The first flange seat 2 includes a first flange plate 21. The first flange plate 21 is provided with a first coupling spline shaft 22 that matches the first spline tooth groove 12 on one side of the central axis of the plate body. The second flange seat 3 includes a second flange plate 31 , the second flange plate 31 is provided with a second coupling spline shaft 32 that matches the second spline tooth groove 13 on one side of the disk body central axis. The spline length of the first coupling spline shaft 22 is consistent with the second spline shaft 22 . The lengths of the keyways of the first spline tooth groove 12 are the same, and the first mating spline shaft 22 and the first spline tooth groove 12 are assembled and fixed through the liquid nitrogen cold assembly process. The splines of the second mating spline shaft 32 are The length is the same as the keyway length of the second spline tooth groove 13, and the second coupling spline shaft 32 and the second spline tooth groove 13 are assembled and fixed through the liquid nitrogen cold assembly process, and the tapered transmission shaft is assembled in an integrated manner. At this time, the matching of the first mating spline shaft 22 and the first spline tooth groove 12 and the matching of the second mating spline shaft 32 and the second spline tooth groove 13 are assembled and fixed in the liquid nitrogen cold assembly process. Next, assemble the first flange seat 2 and the second flange seat 3 on the taper shaft 1 in sequence, and match the tooth packaging of the spline shaft and the spline tooth groove, which can improve the two sets of flange seats and the taper shaft 1 The solidity of the integrated assembly prevents the flange seat from rotating due to excessive torque.

The taper shaft 1 is integrally assembled with the high-speed engine drive shaft 4 through the first flange seat 2, and the taper shaft 1 is integrally assembled with the rotor 5 through the second flange seat 3. The other side of the central axis of the first flange 21 A first assembly spline shaft 23 that is adapted to the high-speed engine drive shaft 4 is provided, and a second assembly spline shaft 33 that is adapted to the rotor 5 is provided on the other side of the central axis of the second flange plate 31 , a first gasket groove is provided on the side of the first flange plate 21 close to the first assembly spline shaft 23, and the first gasket groove is lined with a first sealing gasket 24. The first sealing gasket 24 is relative to The disk surface of the first flange plate 21 extends outward by 1~2 mm. A second gasket groove is provided on the side of the disk surface of the second flange plate 31 close to the second assembly spline shaft 33, and the inner lining of the second gasket groove is There is a second sealing gasket 34, which extends 1~2mm outward relative to the surface of the second flange 31. When the tapered transmission shaft, the high-speed engine drive shaft 4 and the rotor 5 are integrated, the second sealing gasket 34 is passed The tooth meshing assembly of the first assembly spline shaft 23 and the second assembly spline shaft 33 can, on the one hand, improve the accuracy of the transmission ratio between each other, and on the other hand, facilitate precise assembly, and when the first flange seat 2, When the second flange seat 3 is matched and assembled with the high-speed engine drive shaft 4 and the output shaft of the rotor 5 in sequence, the deformation and extrusion sealing of its first sealing gasket 24 and second sealing gasket 34 can improve the sealing performance of the contact end of the output shaft. , to avoid adhesion corrosion from external dust, rain, etc.

A method for manufacturing a helicopter rotor tapered transmission shaft comprises the following steps:

Process one: forging blank,

(1) Preheat treatment: Before forging, the selected material is subjected to low-temperature tempering treatment to improve the plasticity and toughness of the material;

(2) Hot forging: placing the preheated material into the forging equipment for hot forging, changing the grain structure and shape of the material through thermal deformation to improve the material strength and plasticity;

(3) Cold extrusion, processed using cold extrusion technology to ensure its geometric dimensions and surface quality;

Step 2: Aging treatment, using quenching and tempering processes to improve the hardness and toughness of the material, and enhance its fatigue resistance and corrosion resistance;

Process 3: Rough turning of the outer circle, based on the CNC lathe method, using its rough turning tool to remove the excess material;

Process 4: Finishing the outer circle, based on the CNC lathe method, using its outer circle finishing tool to remove the small amount of margin left after rough turning on the material to meet the dimensional process specifications;

Process 5: Spline toothing, based on the CNC milling machine, use its milling cutter to process the corresponding spline shaft and spline tooth groove on the finished material;

Step 6: Final inspection,

(1) Based on visual inspection, manually observe the integrity of the surface processing technology of the processed materials and the matching of the spline shaft and spline tooth grooves;

(2) Based on the measurement and testing method, whether the dimensional accuracy of the processed materials using measuring instruments reaches the standard;

(3) Based on mechanical testing methods, including but not limited to pushing, pulling or rotating methods, test the bearing capacity of the processed materials to determine whether their mechanical properties meet the requirements.

For the materials in the first process, considering that the taper shaft often accelerates and rotates forward and reverse during the rotation process, and it often bears alternating loads and impact loads during the working process, forgings are selected so that the metal fibers are not cut off. The forging dimensions of the forgings are matched in advance according to the machining dimensions of the taper shaft, and the material of the forgings is first titanium alloy or aluminum alloy.

The processing lathe in process three and process four can be carried out in the following ways:

First, the cycloidal pinwheel reducer BWD87-1.5Kw-6 is used, and the output speed n1=3.67r/min is calculated through the two-level deceleration with a pulley speed ratio of 1:3; secondly, the machine tool chuck speed reaches n2=25r/min. ;Third, the screw pitch is set to t=6mm;

Through the above method, first, the distance moved by the screw rod for each rotation should be changed to T=6mm/r; second, the required feed rate s=n1*T=15mm/min is calculated; third, the speed and feed rate must match, and this speed transmission ratio meets the actual processing accuracy requirements.

The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can, within the technical scope disclosed in the present invention, use the technology of the present invention. Any equivalent substitution or change of the scheme and its inventive concept shall be covered by the protection scope of the present invention.

Claims (8)

1. The utility model provides a helicopter rotor tapering transmission shaft, its characterized in that, include tapering axle (1), install in first flange seat (2) of tapering axle (1) axostylus axostyle one end and install in second flange seat (3) of tapering axle (1) axostylus axostyle other end, tapering axle (1) is through first flange seat (2) and the integrative assembly of high-speed engine drive shaft (4), and tapering axle (1) is through the integrative assembly of second flange seat (3) and rotor (5), wherein:

the taper shaft (1) comprises a taper shaft body (11), a first spline tooth groove (12) is formed in one end of a shaft rod of the taper shaft body (11), a second spline tooth groove (13) is formed in the other end of the shaft rod of the taper shaft body (11), and the taper angle of the taper shaft body (11) is 3 degrees;

the first flange seat (2) comprises a first flange plate (21), a first involution spline shaft (22) involuted with the first spline tooth groove (12) is arranged on one side of a disc body central shaft of the first flange plate (21), and a first assembly spline shaft (23) matched with the high-speed engine driving shaft (4) is arranged on the other side of the disc body central shaft of the first flange plate (21);

the second flange seat (3) comprises a second flange plate (31), a second involution spline shaft (32) involuted with the second spline tooth groove (13) is arranged on one side of a disc body central shaft of the second flange plate (31), and a second assembly spline shaft (33) matched with the rotor wing (5) is arranged on the other side of the disc body central shaft of the second flange plate (31).

2. The helicopter rotor taper transmission shaft according to claim 1, wherein the spline length of the first involution spline shaft (22) is the same as the spline length of the first spline tooth groove (12), and the first involution spline shaft (22) and the first spline tooth groove (12) are assembled and fixed through a liquid nitrogen cold-fitting process.

3. The helicopter rotor taper transmission shaft according to claim 1, wherein the spline length of the second involution spline shaft (32) is the same as the spline length of the second spline tooth groove (13), and the second involution spline shaft (32) and the second spline tooth groove (13) are assembled and fixed through a liquid nitrogen cold-fitting process.

4. The helicopter rotor taper transmission shaft according to claim 1, wherein a first gasket groove is formed in one side, close to the first assembling spline shaft (23), of the disc surface of the first flange plate (21), a first sealing gasket (24) is arranged in the first gasket groove in a lining mode, and the first sealing gasket (24) extends out by 1-2 mm relative to the disc surface of the first flange plate (21).

5. The helicopter rotor taper transmission shaft according to claim 1, wherein a second gasket groove is formed in a side, close to the second assembling spline shaft (33), of the disc surface of the second flange plate (31), and a second sealing gasket (34) is arranged in the second gasket groove in a lining mode, and the second sealing gasket (34) extends out by 1-2 mm relative to the disc surface of the second flange plate (31).

6. The helicopter rotor taper transmission shaft according to claim 1, wherein the taper shaft body (11) has a truncated cone structure, and the taper calculation formula is: c= (D-D)/L;

wherein C represents the taper ratio, D represents the large end diameter, D represents the small end diameter, and L represents the length of the taper.

7. The method for manufacturing the tapered transmission shaft of the helicopter rotor according to any one of claims 1 to 6, comprising the following steps:

step one: forging the blank, wherein the blank is forged,

(1) Preheating, and tempering selected materials at low temperature before forging to improve the plasticity and toughness of the materials;

(2) Hot forging, namely placing the preheated material into forging equipment for hot forging, and changing the grain structure and shape of the material through thermal deformation to improve the strength and plasticity of the material;

(3) Cold extrusion, processing by adopting a cold extrusion process, and ensuring the geometric dimension and the surface quality of the product;

step two: aging treatment, namely adopting quenching and tempering processes to treat, improving the hardness and toughness of the material, and enhancing the fatigue resistance and corrosion resistance of the material;

step three: rough turning an outer circle, and turning redundant parts of the material by using an outer circle rough turning tool based on a numerical control lathe form;

and step four: finish turning the outer circle, and turning a small amount of left allowance on the material after rough turning by using an outer circle finish turning tool based on a numerical control lathe form to reach the dimension and technological specification;

step five: spline tooth forming, namely processing a corresponding spline shaft and a spline tooth slot on the finished material by utilizing a milling cutter based on a numerical control milling machine mode;

step six: the final inspection is carried out,

(1) Based on the visual detection form, the integrity of the surface processing technology of the processing material and the matching condition of the spline shaft and the spline tooth socket are observed by manpower;

(2) Based on the measurement and detection form, adopting a measuring instrument to judge whether the dimensional accuracy of the processed material reaches the standard;

(3) And testing the bearing capacity of the processing material based on mechanical detection modes including but not limited to pushing, pulling or rotating modes so as to judge whether the mechanical properties of the processing material meet the requirements.

8. The method according to claim 7, wherein the material in the first step is a forging piece, which is selected so that the metal fiber is not cut, the forging size of the forging piece is matched and corresponding in advance according to the machining size of the taper shaft, and the material of the forging piece is firstly titanium alloy or aluminum alloy, considering that the taper shaft is often accelerated and rotated forward and backward in the rotating process and is often subjected to alternating load and impact load in the working process.