A vibration stress measuring device for aviation cylindrical gears

Abstract

The present invention discloses a vibration stress measuring device for aviation cylindrical gears, comprising: at least one optical fiber strain gauge, arranged on the spoke plate of the gear; an adapter plug, assembled in the hollow shaft of the gear and synchronously rotated with the gear; the adapter plug is provided with a hollow channel connected to the hollow shaft of the gear; an optical fiber slip ring feeder, used to receive the strain signal of the optical fiber strain gauge and transmit the strain signal to a data processing device; the optical fiber slip ring feeder has an optical fiber slip ring feeder stator and an optical fiber slip ring feeder rotor; the optical fiber slip ring feeder rotor is assembled with the adapter plug; the optical fiber slip ring feeder stator is positioned on the gear box casing through an adapter seat. The optical fiber slip ring feeder in the present invention generates very little heat, and thus the optical fiber slip ring feeder does not require special lubrication and cooling devices, the measurement system is simple, and the measurement is very convenient.

Description

Technical Field

[0001] The invention relates to the technical field of gear vibration stress measurement, and in particular to an aviation cylindrical gear vibration stress measurement device, which is applied to a 1000kW-class aviation gas turbine shaft engine. Background Art

[0002] The cylindrical gears of aircraft engine gearboxes have the characteristics of high speed and wide speed range. The gears of the gearbox work in an oil mist environment (a mixture of lubricating oil and air with a certain pressure, and the temperature is generally over 100°C). Due to the characteristics of high speed, wide speed range and complex vibration environment, the dynamic simulation design of the cylindrical gears of aircraft engine gearboxes is relatively difficult, and the actual distribution of vibration stress is difficult to obtain through simulation methods. Therefore, it is necessary to measure the actual distribution of vibration stress through vibration stress measurement tests.

[0003] In order to carry out the above vibration stress measurement test, a corresponding vibration stress measurement device is required. At present, the vibration stress measurement of aviation cylindrical gears is generally carried out by the strain gauge method. The strain gauge is pasted on the gear to be measured. When the gearbox is in working condition, the deformation data of the strain gauge pasted on the gear is collected, and the actual distribution of the vibration stress of the wheel body is evaluated based on the collected data. The strain signal on the rotating part is transmitted to the stationary signal analysis device using a slip ring induction device. The lubrication and cooling of the slip ring induction device are realized through a special mobile lubrication device (or lubrication station).

[0004] In order to transmit the strain signal on the rotating part to the stationary signal analysis equipment, a signal extraction device, namely a slip ring inductor, is required. The slip ring inductor rotates at high speed with the gear being measured. The slip ring will generate a large amount of heat during the high-speed friction process, which is difficult to dissipate, causing the temperature of the entire device to rise rapidly, resulting in the temperature of the conductive ring and the brush wire to rise, which is prone to abnormalities and requires a special cooling device. However, the cooling device in the prior art is large in size and difficult to carry, which brings inconvenience to the measurement work, especially when the slip ring inductor is installed vertically, the lubrication and cooling conditions are very strict, and measurement interruption due to high temperature is prone to occur. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect that when performing vibration stress measurement test on aviation cylindrical gears, the use of slip ring induction device requires a special cooling device, which brings inconvenience to the measurement, thereby providing an aviation cylindrical gear vibration stress measurement device.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] An aviation cylindrical gear vibration stress measuring device, comprising:

[0008] At least one optical fiber strain gauge, disposed on a spoke plate of the gear;

[0009] The adapter plug is assembled in the hollow shaft of the gear and rotates synchronously with the gear; the adapter plug is provided with a hollow channel connected to the hollow shaft of the gear;

[0010] The optical fiber slip ring induction device is used to receive the strain signal of the optical fiber strain gauge and transmit the strain signal to the data processing equipment; the optical fiber slip ring induction device comprises an optical fiber slip ring induction device stator and an optical fiber slip ring induction device rotor; the optical fiber slip ring induction device rotor is assembled with an adapter plug; the optical fiber slip ring induction device generates very little heat and does not require a special cooling device; the optical fiber slip ring induction device stator is positioned on the gear box casing through an adapter seat.

[0011] To further optimize the technical solution, the aviation cylindrical gear dynamic stress measurement device performs gear vibration stress measurement based on the optical fiber slip ring measurement method.

[0012] To further optimize the technical solution, a U-shaped groove is provided on the top surface of the adapter plug, and a pin hole is provided on the bottom side wall of the optical fiber slip ring lead rotor; a pin is passed through the pin hole, and the pin is positioned in the U-shaped groove.

[0013] To further optimize the technical solution, the U-shaped groove and the latch are heat treated;

[0014] And / or the outer surface of the adapter is made of metal material and is anodized.

[0015] To further optimize the technical solution, at least one threading hole is opened on the side wall of the hollow shaft of the gear, and the optical fiber strain gauge is connected to the optical fiber slip ring lead rotor through the optical fiber strain gauge lead passing through the threading hole.

[0016] To further optimize the technical solution, a plurality of optical fiber strain gauges are adhered to the spoke plate of the gear in radial and axial distribution.

[0017] To further optimize the technical solution, the optical fiber strain gauge is pasted according to the strength of the spoke plate of the gear and the vibration finite element calculation results.

[0018] To further optimize the technical solution, a flange is connected to the side wall of the stator of the optical fiber slip ring guide, and the flange is located above the adapter; the flange is respectively fixed on the adapter and the gear box casing.

[0019] To further optimize the technical solution, a groove is provided on the top surface of the adapter; an adjustment pad is provided between the flange edge of the optical fiber slip ring lead-in device stator and the groove to adjust the axial position of the optical fiber slip ring lead-in device stator.

[0020] To further optimize the technical solution, the gear and the optical fiber slip ring lead rotor are arranged coaxially, including the following implementation methods:

[0021] The gear and the adapter plug are interference fit;

[0022] The mating surfaces of the optical fiber slip ring lead stator and the adapter seat are clearance matched, and the mating surfaces of the adapter seat and the gear box casing are clearance matched.

[0023] To further optimize the technical solution, a graphite seal is provided between the adapter and the adapter plug to achieve dynamic sealing between the adapter and the adapter plug to prevent lubricating oil leakage from contaminating the optical fiber slip ring lead;

[0024] The adapter and the gear box casing are sealed to each other.

[0025] Further optimizing the technical solution, the graphite seal comprises:

[0026] The graphite seal rotor is mounted on the outer periphery of the adapter plug and rotates synchronously with the gear; the graphite seal rotor and the adapter plug are sealed with each other;

[0027] The graphite seal stator is installed inside the adapter and is stationary; the graphite seal stator and the adapter are sealed to each other;

[0028] The graphite ring is embedded in the top end surface of the graphite seal rotor and is sealed with the bottom end surface of the graphite seal stator.

[0029] The technical solution of the present invention has the following advantages:

[0030] 1. The present invention provides an aviation cylindrical gear vibration stress measuring device, the total weight of the measuring system is light, easy to disassemble, and easy to use. Since the optical fiber slip ring lead itself generates very little heat, the optical fiber slip ring lead does not require special lubrication and cooling devices. The measuring system is simple and the measurement is very convenient. There will be no measurement interruption due to the over-high temperature of the optical fiber slip ring lead.

[0031] 2. The present invention provides an aviation cylindrical gear vibration stress measurement device, which measures the gear vibration stress based on the optical fiber slip ring measurement method. The strain gauge uses an optical fiber strain gauge, and the slip ring induction device uses an optical fiber slip ring induction device. Optical fiber strain gauges have the following advantages over ordinary strain gauges: optical fiber strain gauges are lighter, and the weight of the optical fiber strain gauge lead wire is also light. Under high speed conditions, the survival rate is high, and it is not easy to fall off during the high-speed rotation of the gear, and there is no need to perform repeated measurements; long-term signal stability and system durability are better, and it has excellent electromagnetic and radio frequency interference resistance, so the problem that the strain signal of ordinary strain gauges is easily interfered by electromagnetic fields will not occur, and the reliability of measurement data is better; and optical fiber strain gauges can adapt to harsh environments and are more suitable for the oil mist environment of gear boxes.

[0032] 3. In an aviation cylindrical gear vibration stress measuring device provided by the present invention, the U-shaped groove surface and the pin surface on the adapter plug are heat treated to improve the surface hardness and make the hardness of the two equivalent, thereby improving the wear resistance of the contact surface; the adapter seat exposed to the outside is made of metal material, preferably aluminum alloy material, and the surface of the adapter seat is anodized to improve the corrosion resistance of the adapter seat; the above measures can realize long-term repeated use of the measuring device.

[0033] 4. The present invention provides an aviation cylindrical gear vibration stress measuring device, which uses a large clearance fit between the pin and the U-shaped groove on the adapter plug, and between the optical fiber slip ring lead rotor and the inner hole of the adapter plug, thereby preventing over-positioning. The pin and the optical fiber slip ring lead rotor use an interference fit, which effectively prevents the pin from loosening during rotation.

[0034] 5. The present invention provides an aviation cylindrical gear vibration stress measuring device. Taking into account the axial manufacturing error, the present invention designs an adjustment pad between the fiber optic slip ring lead and the adapter, and the axial position of the fiber optic slip ring lead can be adjusted as needed.

[0035] 6. In the vibration stress measuring device for aviation cylindrical gears provided by the present invention, a graphite seal is arranged between the adapter seat and the adapter plug, which effectively prevents the leakage of lubricating oil from contaminating the optical fiber slip ring lead;

[0036] The adapter and the gearbox casing are sealed to each other, and the oil and gas in the gearbox will not leak, thus avoiding pollution to the measuring device and the environment.

[0037] 7. The present invention provides an aviation cylindrical gear vibration stress measurement device, in which a plurality of optical fiber strain gauges are respectively attached to the radial and axial upper edges of the gear spokes, and can simultaneously realize the measurement of the gear in-plane vibration and out-of-plane vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 It is a structural schematic diagram of a vibration stress measuring device for aviation cylindrical gears according to the present invention;

[0040] Figure 2 It is a partially enlarged schematic diagram of part I of a vibration stress measuring device for aviation cylindrical gears of the present invention;

[0041] Figure 3 It is a structural schematic diagram of a transfer plug of an aviation cylindrical gear vibration stress measuring device of the present invention;

[0042] Figure 4 It is a structural schematic diagram of an optical fiber slip ring lead of an aviation cylindrical gear vibration stress measuring device of the present invention;

[0043] Figure 5 It is a schematic diagram of the sticking of the optical fiber strain gauge when the vibration stress measuring device of the aviation cylindrical gear of the present invention is measuring the vibration within the gear surface;

[0044] Figure 6 The present invention is a schematic diagram of the pasting of optical fiber strain gauges when an aviation cylindrical gear vibration stress measurement device is performing gear off-plane vibration measurement.

[0045] Reference numerals:

[0046] 1. Fiber optic slip ring lead, 2. first screw, 3. adapter, 4. gearbox casing, 5. gear, 6. bearing, 7. adapter plug, 71. U-shaped groove, 8. first O-ring, 9. latch, 10. graphite seal, 11. second O-ring, 12. third O-ring, 13. graphite seal stator, 14. fourth O-ring, 15. graphite ring, 16. fiber optic strain gauge, 17. fiber optic strain gauge lead, 18. second screw, 19. adjustment pad, 20. fiber optic slip ring lead, 21. graphite seal rotor, 22. threading hole, 23. flange edge, 24. mounting hole. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0049] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0051] like Figures 1 to 6 As shown, this embodiment discloses a vibration stress measuring device for aviation cylindrical gears, including: an optical fiber strain gauge 16, an adapter plug 7, an adapter seat 3 and an optical fiber slip ring lead 1.

[0052] At least one optical fiber strain gauge 16 is provided, that is, one or more optical fiber strain gauges 16 are provided. The optical fiber strain gauge 16 is pasted on the spoke plate of the gear 5.

[0053] The adapter plug 7 is assembled in the hollow shaft of the gear 5 and rotates synchronously with the gear 5. The adapter plug 7 is provided with a hollow passage communicated with the hollow shaft of the gear 5.

[0054] The optical fiber slip ring lead 1 is used to receive the strain signal of the optical fiber strain gauge 16 and transmit the strain signal to the data processing device. Figure 4As shown, the optical fiber slip ring induction device 1 has an optical fiber slip ring induction device stator and an optical fiber slip ring induction device rotor. The optical fiber slip ring induction device rotor is assembled with an adapter plug 7; and the optical fiber slip ring induction device stator is positioned on the gear box casing 4 through an adapter seat 3.

[0055] The gear 5 in the present invention is supported in the gear box by two bearings 6, and the two bearings 6 are respectively located at the upper and lower sides of the gear blade. The inside of the gear box is a mixture of lubricating oil and air with a certain pressure.

[0056] The above-mentioned aviation cylindrical gear vibration stress measuring device has a simple measuring system and is very convenient because the fiber optic slip ring lead generates very little heat, and thus the fiber optic slip ring lead 1 does not require special lubrication and cooling devices. There will be no measurement interruption due to excessive temperature of the fiber optic slip ring lead.

[0057] The traditional strain gauge itself is large in size and weight, and the weight of the strain gauge lead is also relatively large. Under high rotation speed conditions, the centrifugal force is large. Due to the centrifugal force, the strain gauge is prone to loosening or even falling off. The loose strain gauge makes the reliability of the measurement data low, and even makes it impossible to measure, and repeated measurements are often required. At the same time, repeated measurements will lead to repeated disassembly and assembly of the test piece, consuming a lot of manpower and material resources. In order to solve this technical problem, the strain gauge in the present invention uses an optical fiber strain gauge, and the slip ring induction device uses an optical fiber slip ring induction device. The present invention measures the gear vibration stress based on the optical fiber slip ring measurement method.

[0058] Optical fiber strain gauges have the following advantages over ordinary strain gauges: smaller size and weight, so they are less likely to fall off during high-speed rotation of gears, and there is no need for repeated measurements; long-term signal stability and system durability are better, optical signals have strong resistance to electromagnetic interference, and have excellent immunity to electromagnetic and radio frequency interference, so ordinary strain gauge strain signals are not easily disturbed by electromagnetic fields, and the reliability of measurement data is better; and optical fiber strain gauges can adapt to harsh environments and are more suitable for the oil mist environment of gearboxes.

[0059] like Figure 3 As shown, a pair of mutually symmetrical U-shaped grooves 71 are provided on the top surface of the adapter plug 7. Figure 4 As shown, a pair of mutually symmetrical pin holes are provided on the bottom side wall of the optical fiber slip ring lead rotor. A plug 9 is inserted into the pin hole, and the plug 9 is positioned in the U-shaped groove 71. After the plug 9 in the present invention is inserted into the adapter plug 7, the plug 9 is directly positioned in the U-shaped groove 71 to achieve the connection and positioning between the optical fiber slip ring lead rotor and the adapter plug 7.

[0060] In order to achieve long-term repeated use of the above measuring device, the U-shaped groove surface on the adapter plug 7 and the surface of the pin 9 are heat treated to increase the surface hardness and make the hardness of the two equal, thereby improving the wear resistance of the contact surface.

[0061] The adapter seat 3 exposed to the outside is made of metal material, preferably aluminum alloy material. In order to improve the corrosion resistance of the adapter seat 3, the surface of the adapter seat 3 is anodized.

[0062] In order to prevent over-positioning, a large clearance is used between the plug 9 and the U-shaped groove on the adapter plug 7, and between the optical fiber slip ring lead rotor and the inner hole of the adapter plug 7. In order to prevent the plug 9 from loosening during rotation, an interference fit is used between the plug 9 and the optical fiber slip ring lead rotor.

[0063] At least one threading hole 22 is provided on the side wall of the hollow shaft of the gear 5; the number of threading holes 22 is less than the number of optical fiber strain gauges 16, or the number of threading holes 22 is equal to the number of optical fiber strain gauges 16. The optical fiber strain gauge lead wire 17 is led out from the optical fiber strain gauge 16, passes through the threading hole 22 and extends into the hollow shaft of the gear 5, and finally electrically connected to the optical fiber slip ring lead rotor.

[0064] like Figure 5 and Figure 6 As shown, in order to simultaneously measure the gear surface vibration and the out-of-plane vibration (axial vibration), the present invention adheres multiple optical fiber sensors (optical fiber strain gauges) on the gear spoke plate in the radial and axial directions, and each optical fiber strain gauge is connected in series in sequence.

[0065] When the optical fiber strain gauge 16 is pasted, it is performed according to the strength of the spoke plate of the gear 5 and the vibration finite element calculation results. The optical fiber strain gauge should cover the area with relatively large stress.

[0066] A flange 23 with a mounting hole 24 is connected to the side wall of the optical fiber slip ring lead stator, and the flange 23 is located above the adapter 3. The flanges are respectively fixed to the adapter 3 and the gearbox casing 4. More specifically, the flange is locked and positioned on the adapter 3 by a plurality of first screws 2, and the adapter 3 is locked and positioned on the gearbox casing 4 by a second screw 18.

[0067] Taking into account the axial manufacturing error, the present invention designs an adjustment pad 19 between the optical fiber slip ring feeder 1 and the adapter 3. A groove is provided on the top surface of the adapter 3. An adjustment pad 19 is provided between the flange edge of the optical fiber slip ring feeder stator and the groove, and the specification and model of the adjustment pad 19 can be replaced as needed to adjust the axial position of the optical fiber slip ring feeder.

[0068] The high-speed rotating gear 5 and the optical fiber slip ring induction device rotor should be arranged coaxially, otherwise the optical fiber slip ring induction device 1 may be damaged due to the restraining force caused by eccentricity. Figure 1 To ensure the coaxiality, the gear 5 and the adapter plug 7 use a high-precision interference fit. The stator part of the optical fiber slip ring guide has a cylindrical surface, such as Figure 1 , align the stator part of the optical fiber slip ring lead 1 with the mating surface A (see Figure 1 The adapter 3 and the gearbox casing 4 are matched with each other on the matching surface B (see Figure 1 Marking), mating surface C (see Figure 1 The gear 5 is designed to be matched with a small clearance of high precision, which is convenient for assembly and ensures that the gear 5 is coaxial with the optical fiber slip ring guide rotor.

[0069] In order to prevent the lubricating oil from leaking and contaminating the optical fiber slip ring lead 1, a graphite seal 10 is provided between the adapter seat 3 and the adapter plug 7 to achieve dynamic sealing between the adapter seat 3 and the adapter plug 7. The graphite seal can achieve dynamic sealing between high-speed rotating parts and stationary parts. A first O-ring 8 and a second O-ring 11 are installed between the adapter seat 3 and the gear box casing 4 to achieve static sealing between the adapter seat 3 and the gear box casing 4.

[0070] The adapter plug 7 in the present invention is configured as a stepped cylinder, which is configured as a first stepped cylinder, a second stepped cylinder, and a third stepped cylinder from bottom to top; the inner hole of the adapter seat 3 is configured as a stepped hole, which is configured as a first stepped hole, a second stepped hole, a third stepped hole, and a fourth stepped hole from bottom right to top. Among them, the graphite seal 10 is located between the second stepped cylinder of the adapter plug 7 and the first stepped hole of the adapter seat 3. The second stepped cylinder and the third stepped cylinder of the adapter plug 7, as well as the rotor part of the optical fiber slip ring lead are all located in the inner hole of the adapter seat 3.

[0071] The graphite seal 10 includes: a graphite seal rotor 21, a graphite seal stator 13 and a graphite ring 15. The graphite seal rotor 21 is mounted on the periphery of the adapter plug 7 and rotates synchronously with the gear 5. The graphite seal rotor 21 and the adapter plug 7 are sealed by a third O-ring 12. The graphite seal stator 13 is mounted inside the adapter seat 3 and is stationary. The graphite seal stator 13 and the adapter seat 3 are sealed by a fourth O-ring 14. The graphite ring 15 is embedded on the top end surface of the graphite seal rotor 21 and is sealed with the bottom end surface of the graphite seal stator 13. The graphite ring 15 on the graphite seal rotor 21 rotates with the graphite seal rotor 21, and the graphite ring 15 is in contact with the graphite seal stator 13 when rotating, thereby achieving sealing between the graphite ring 15 and the graphite seal stator 13.

[0072] The working process of the present invention is as follows:

[0073] When the gear 5 rotates, it drives the adapter plug 7 to rotate, thereby driving the latch 9 to rotate, and finally driving the optical fiber slip ring induction device rotor to rotate. The optical fiber strain gauge lead 17 and the optical fiber strain gauge 16 rotate synchronously with the gear 5. Signals can be transmitted between the optical fiber slip ring induction device rotor and the optical fiber slip ring induction device stator. The optical fiber slip ring induction device 1 is connected to the data processing device through the optical fiber slip ring induction device lead 20 located outside the gear box on the optical fiber slip ring induction device stator. The strain signal of the optical fiber strain gauge 16 is transmitted to the data processing device through the optical fiber slip ring induction device 1 to realize the measurement of gear vibration stress.

[0074] The present invention can achieve the purpose of measuring the vibration stress of high-speed cylindrical gears using an optical fiber sensor. While measuring the vibration stress, the device can realize reliable dynamic sealing of the gear box and avoid leakage of pressure oil mist. The device has a light total weight, is easy to disassemble, and is easy to use. Under high speed conditions, the survival rate of the optical fiber strain gauge is high. The device has strong anti-electromagnetic interference ability and high reliability of measurement data. The device does not require a special lubrication and cooling system, and the measurement system structure is simple.

[0075] The invention has been subjected to a dynamic stress measurement test with aviation gas turbine engine components. The predetermined function was achieved in the test, the gear dynamic stress data was measured, and the sensor was not damaged.

[0076] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the invention.

Claims

1. A vibration stress measuring device for aviation cylindrical gears, characterized in that: The device measures the gear vibration stress in an oil mist environment based on an optical fiber slip ring measurement method, and the device comprises: At least one optical fiber strain gauge (16) arranged on a spoke plate of the gear (5); The adapter plug (7) is assembled in the hollow shaft of the gear (5) and rotates synchronously with the gear (5); the adapter plug (7) is provided with a hollow passage connected to the hollow shaft of the gear (5); An optical fiber slip ring induction device (1) is used to receive a strain signal from an optical fiber strain gauge (16) and transmit the strain signal to a data processing device; the optical fiber slip ring induction device (1) comprises an optical fiber slip ring induction device stator and an optical fiber slip ring induction device rotor; the optical fiber slip ring induction device rotor is assembled with an adapter plug (7); the optical fiber slip ring induction device stator is positioned on a gear box casing (4) via an adapter seat (3); A graphite seal (10) is provided between the adapter seat (3) and the adapter plug (7) for achieving a dynamic seal between the adapter seat (3) and the adapter plug (7) to prevent lubricating oil from leaking and contaminating the optical fiber slip ring lead (1); The adapter seat (3) and the gear box casing (4) are sealed with each other; The graphite seal (10) comprises: The graphite seal rotor (21) is mounted on the periphery of the adapter plug (7) and rotates synchronously with the gear (5); the graphite seal rotor (21) and the adapter plug (7) are sealed with each other; The graphite sealing stator (13) is mounted inside the adapter seat (3) and is stationary; the graphite sealing stator (13) and the adapter seat (3) are sealed with each other; The graphite ring (15) is embedded in the top end surface of the graphite seal rotor (21) and is in close contact with the bottom end surface of the graphite seal stator (13) to form a seal.

2. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: A U-shaped groove (71) is provided on the top surface of the adapter plug (7), and a pin hole is provided on the bottom side wall of the optical fiber slip ring lead rotor; a plug (9) is inserted into the pin hole, and the plug (9) is positioned in the U-shaped groove (71).

3. The vibration stress measuring device for aviation cylindrical gears according to claim 2, characterized in that: The U-shaped groove (71) and the latch pin (9) are heat treated; And / or the outer surface of the adapter (3) is made of metal material and is anodized.

4. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: At least one threading hole (22) is provided on the side wall of the hollow shaft of the gear (5), and the optical fiber strain gauge (16) is connected to the rotor of the optical fiber slip ring lead through an optical fiber strain gauge lead wire (17) passing through the threading hole (22).

5. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: Multiple-point serial optical fiber strain gauges (16) are adhered to the spoke plate of the gear (5) in radial and axial distribution.

6. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: The optical fiber strain gauge (16) is pasted according to the strength and vibration finite element calculation results of the spoke plate of the gear (5).

7. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: A flange is connected to the side wall of the optical fiber slip ring stator, and the flange is located above the adapter seat (3); the flange is respectively fixed to the adapter seat (3) and the gear box casing (4).

8. The vibration stress measuring device for aviation cylindrical gears according to claim 7, characterized in that: A groove is provided on the top surface of the adapter seat (3); an adjustment pad (19) is provided between the flange edge of the optical fiber slip ring lead stator and the groove, and is used to adjust the axial position of the optical fiber slip ring lead stator.

9. The vibration stress measuring device for aviation cylindrical gears according to claim 1, characterized in that: The gear (5) is coaxially arranged with the optical fiber slip ring lead rotor, and includes the following implementation methods: The gear (5) and the adapter plug (7) are interference fit to ensure the coaxiality of the gear (5) and the adapter plug (7); A large clearance is used between the pin and the U-shaped groove on the adapter plug, and between the optical fiber slip ring lead rotor and the inner hole of the adapter plug to prevent over-positioning. Interference fit is used between the pin and the optical fiber slip ring lead rotor to effectively prevent the pin from loosening during rotation; The mating surfaces of the optical fiber slip ring lead stator and the adapter seat (3) are clearance matched, and the mating surfaces of the adapter seat (3) and the gear box casing (4) are clearance matched.

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