CN113340573A

CN113340573A - Sidesway loading rolling device and test method for aircraft wheel fatigue test bed

Info

Publication number: CN113340573A
Application number: CN202110123390.1A
Authority: CN
Inventors: 邓伟林; 张炜; 马晓军; 李晓猛; 刘航; 黄星; 张博强; 陈国慧; 杨薇
Original assignee: Xian Aviation Brake Technology Co Ltd
Current assignee: Xian Aviation Brake Technology Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-09-03

Abstract

A lateral deviation loading device and a testing method of an aircraft wheel fatigue test bed are provided. The outer surface of the drum is used to simulate an airstrip. The guide rollers distributed between the movable frame and the guide frame realize rolling movement between the movable frame and the guide frame, so that the moving resistance is reduced, the defect of load deviation caused by overlarge resistance in the existing guide rail type loading is overcome, and the reliability of the test bed and the reliability of test parameters are improved. The lateral deviation swinging of the lateral deviation loading device of the fatigue life test bed of the aircraft wheel is realized by using a simple driving device; the accuracy of the deflection angle is improved to +/-0.1 degrees by the angle sensor, the labor intensity of workers is reduced, the operation safety of equipment is improved, a reliable and convenient test device is provided for researching airplane wheels and tires with better performance, the sidesway rolling test and the accelerated life test of all military airplanes and civil airplane wheels under specified conditions can be realized, and the device has the characteristics of low test cost and easiness in implementation.

Description

Sidesway loading rolling device and test method for aircraft wheel fatigue test bed

Technical Field

The invention belongs to the aircraft wheel test technology, and particularly relates to a sidesway loading rolling device for an aircraft wheel fatigue test.

Background

The aircraft wheels are important components of an aircraft take-off and landing system, bear dynamic loads and landing instant impact loads of the aircraft during take-off and landing taxis, and static loads of the aircraft during parking and parking, directly influence the sliding performance and the braking and decelerating performance of the aircraft, and have great influence on the take-off and landing safety of the aircraft. With the rapid development of aviation technology in China, the performance of airplanes is continuously improved, the performance requirements on the airplane wheels of the airplanes are greatly improved, the airplane wheels are required to be light in weight, large in bearing capacity and long in service life, particularly, the service life indexes of carbon brake wheels exceed 1000 landing, the service life requirements of the wheels of some military airplanes reach 3000 landing, and the service life requirements of the wheels of civil airplanes reach 5000 landing. When the static strength of the airplane wheel meets the design requirement, the service life index requirement is a main research project of airplane wheel design, the service life of the airplane wheel is mainly influenced by dynamic load fatigue damage, and therefore the strength and fatigue life test of the airplane wheel is required to simulate the actual working condition and carry out in-plant check test before the airplane is installed and used.

The airplane wheel service life test bed is test equipment for checking whether the design service life of an airplane wheel product can meet the technical specification requirements before the airplane wheel product is designed and shaped, a loading rolling test is carried out on the airplane wheel on the service life test bed according to the load spectrum requirements, the rolling test mileage is accumulated, and the service life of the airplane wheel is evaluated. The existing national military standard, navigation standard and enterprise standard of China's aviation wheel fatigue life test are basically the fatigue life test method along with the foreign military standard, and the military aviation wheels are basically evaluated by the test method specified in HB5651 general technical conditions for aviation wheels and GJB1184A general specifications for aviation wheels and brake devices; the fatigue life of the civil aviation airplane wheel is evaluated by adopting a test method specified by the Federal Aviation Administration (FAA) TSO-C135 transport type airplane wheel and brake device and the CTSO-C135 transport type airplane wheel and brake device of China civil aviation, the standard evaluation test method needs a plurality of subsamples for testing, the test period is very long, and the service life evaluation test is carried out on each type of airplane wheel in at least more than one year of test time.

In the nineties of the last century, ARP597(C) supplementary criteria for durability of civil transport airplane wheels and brake design stipulates an accelerated fatigue life test method for airplane wheels, the method increases yawing lateral loads and rolling resistance loads on the basis of American military standards, and according to the load spectrum method, when the airplane wheels are subjected to an accelerated life test, 1 rise and fall is tested in a field, and the service life of the airplane wheels is 5 rises and falls in comparison with that of the airplane wheels which fly in an external field, so that the fatigue life test time of the airplane wheels can be greatly shortened, the accelerated life test method is also adopted in western developed countries, the service life test method is also adopted in TY154 civil airplane localization wheels for life evaluation, and an accelerated life test bed for the airplane wheels needs to be newly built according to the method.

In the new test method, the airplane wheel needs to simulate the actual use working condition to complete the accelerated life test during the test. The airplane is in different working states, and the stress conditions of the airplane wheels are different.

1. The aircraft is in a static state, and the bearing mainly bears static load.

2. When the airplane taxis on the ground, the airplane mainly bears vertical load. Because the ground is not absolutely flat, the vibration amplitude of the airplane is larger than the gravity of the airplane.

3. When landing, the moment when the wheels are grounded is mainly subjected to huge static vertical impact load, and then the wheels are accelerated to reach the same speed as the airplane to slide on the ground at a high acceleration. If the belt is grounded sideways, for example, when the side wind is strong, the wheels are subjected to large side load, and when the wheels are subjected to side friction, the airplane tends to incline to one side due to inertia. Therefore, the service life test of the airplane wheel has 10 percent of mileage and needs to be carried out on the side-bias loading rolling service life test.

At present, an original airplane wheel fatigue life test bed in China is designed and manufactured according to a test method specified by HB5651, GJB1184A, TSO-C135 and CTSO-C135, a yaw loading and roll test is carried out by adopting a yaw test bed movable loading mechanism, the yaw angle is determined by the size of a test load, when the test bed swings in a yaw mode, a crane of a factory building is used for pulling the test bed movable loading mechanism to move around the center of a circle in front of a drum wheel, the operation is complex, the safety and reliability are poor, and the yaw angle is difficult to adjust accurately.

A side loading device is proposed in the invention of application No. 201810777177.0. The lateral loading device is characterized in that a circle of roller chain is arranged on the outer edge of an outer guide rail, a driving motor is arranged at the tail of a bracket, when lateral angle deflection is realized, the driving motor is started to drive a chain wheel to rotate, the bracket is pushed to deflect by the meshing of the chain wheel and the roller chain, and the deflection angle is visually determined by an arranged angle scale. The disadvantages of this side loading device are indicated by: firstly, the precision of the deflection angle is limited by the pitch number of the roller chain because the chain wheel needs to be meshed with the roller chain. Its two, the loading mode of wheel, its scheme is at the top installation wheel support guide rail of large-scale bracket, and the loading load direction and the rack atress direction of wheel are not on same horizontal plane, and wheel load direction is wheel axle center place horizontal plane, and the bracket atress is transmitted to the bracket by wheel support guide rail, and the wheel is when carrying out the resistance loading, and its resistance moment direction is the perpendicular to horizontal plane, makes like this the resultant force act on wheel support guide rail and forms lever power, consequently makes this kind of loading mode greatly limited its loading. Thirdly, this kind of guide rail installation's mode, there is great clearance in the upper portion between guide rail and the slider, and the test bench has great vibration under the loading of wheel load at the rotation of big quality drum wheel, can make wheel mounting bracket vibrate from top to bottom, and this clearance is the fatal defect of this kind of loading mode.

Disclosure of Invention

The invention provides a lateral deviation loading rolling device and a testing method of an aircraft wheel fatigue testing stand, aiming at overcoming the defect that an aircraft wheel acceleration fatigue life test cannot be carried out in the prior art.

The lateral-deviation loading rolling device of the aircraft wheel fatigue test bed comprises a drum, a main shaft, a base plate assembly, a steering frame, an axle, a U-shaped loading head, a guide frame, a movable frame, a loading oil cylinder, an outer side slide rail, an inner side slide rail, a lateral-deviation oil cylinder, a supporting oil cylinder, an outer slide rail fastening screw rod, an inner slide rail fastening screw rod, a load sensor and a vertical-direction guide roller. Wherein: the spindle is mounted on an upper surface of the substrate assembly. The drum is mounted on the main shaft and is freely rotatable. One end of the steering frame is connected with the inner side surface of the substrate assembly, and the other end of the steering frame is fixedly connected with one side surface of the movable frame. An angular displacement sensor is arranged on a steering shaft of the bogie and is used for being matched with the side deviation swinging oil cylinder to ensure the accurate positioning of the side deviation angle of the movable loading head. The U-shaped loading head is fixed in the frame of the steering frame; a rotating shaft for mounting the wheel is arranged in the frame of the U-shaped loading head. The central line of the rotating shaft is parallel to the central line of the main shaft. The outer slide rail and the inner slide rail are both positioned on one side of the steering frame, and the outer slide rail and the inner slide rail are parallel. The upper surface of the outer slide rail is provided with a supporting roller. A lateral deviation oil cylinder is arranged on the surface of one end of the outer side sliding rail; two supporting oil cylinders are arranged on the end surface of the movable frame at the end of the outer guide rail; the loading oil cylinder is positioned at the geometric center of the guide frame and is fixed on a cross beam of the movable frame. The guide frame is placed in the middle of the movable frame and is in sliding fit with the surface of the guide frame through the vertical guide roller and the lateral guide roller so as to reduce the friction resistance of the guide frame during movement.

And a lateral deviation oil cylinder is arranged on the surface of one end of the outer side sliding rail. Two supporting oil cylinders are arranged on the end surface of the movable frame at the end of the outer guide rail.

The surface of the movable frame, which is close to one side of the drum, is fixedly connected with one end of the steering frame through a steering frame mounting plate; the other end of the steering frame is axially connected with the swinging shaft in the base plate assembly through a ball shaft.

Two groups of vertical guide rollers are respectively arranged on the upper surface and the lower surface in the movable frame, and two groups of lateral guide rollers are respectively arranged on the two side surfaces in the movable frame through connecting plates. The guide frame is placed in the middle of the inside of the movable frame and supported by the vertical guide rollers and the lateral guide rollers so that the vertical guide rollers and the lateral guide rollers are slidably engaged with the surface of the guide frame. The height of the guide frame is equal to that of the loading head, and one end of the guide frame is fixedly connected with one end of the U-shaped loading head. The wheel is arranged on a wheel shaft at the other end of the U-shaped loading head. One end of the movable frame is provided with a connecting lug fixed with the outer side slide rail; and the other end of the movable frame is also provided with a connecting lug fixed with the inner side slide rail.

The base plate assembly comprises a swing shaft, a bearing outer ring, a ground shroud plate, a retainer ring and a connecting reinforcing plate. The swinging shaft penetrates through the through hole in the floor shroud plate, one end of the swinging shaft is positioned on the upper surface of the floor shroud plate, and the other end of the swinging shaft is positioned on the lower surface of the floor shroud plate. The connecting reinforcing plate is positioned on the upper surface of the floor covering plate and sleeved on the swinging shaft; the connection reinforcing plate is fixed by a retainer ring. The bearing is positioned on the lower surface of the floor covering plate and is sleeved on the swinging shaft.

The radius of the outer side slide rail is 5000 mm. The upper surface of the outer side sliding rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm. And a mounting hole for mounting the lateral deviation oil cylinder is formed in the surface of one end of the outer side slide rail. The radius of the inner side slide rail is 3000 mm. The upper surface of the inner side slide rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm.

The bogie is of a U-shaped frame structure, the opening end of the bogie is used for connecting a connecting plate of the movable frame, the other end of the bogie is a bearing mounting seat, and the inner surface of the bearing mounting seat is a spherical surface matched with the outer surface of the bearing outer ring. The bearing mounting seat is sleeved on the bearing outer ring, and the bearing mounting seat and the bearing outer ring are in running fit. When the side deviation oil cylinder works, the bogie can horizontally rotate 20 degrees to two sides around the central line of the swinging shaft respectively, so that the movable frame is driven to laterally deviate and displace, and the wheel is driven to laterally deviate by the same angle, and a side deviation angle is formed between the surface of the wheel and the surface of the drum wheel; when the supporting oil cylinder works, the bogie can move up and down along the outer circumferential surface of the bearing outer ring, so that the movable frame can move up by 50 mm. The vertical extension line of the central line of the swinging shaft is tangent to the point A of the outer circle surface of the drum wheel closest to the wheel.

The vertical guide roller is of a double-wheel structure and comprises a roller frame, a roller shaft and a roller. The roller carrier is a double-support, and two roller mounting grooves are arranged on the roller carrier side by side. The two roller shafts are arranged on the upper end surface of the roller frame side by side and are fixed through roller shaft pressing plates. Each roller is mounted on the roller shaft through a bearing. The lateral guide roller and the vertical guide roller have the same structure.

The number of the lateral guide rollers is 8, and the lateral guide rollers are divided into two groups; the two groups of lateral guide rollers are symmetrically and horizontally arranged on the inner surface of the movable frame. The number of the vertical guide rollers is also 8, and the vertical guide rollers are divided into two groups; the two groups of vertical guide rollers are symmetrically and vertically arranged on the inner side surface of the movable frame. The lateral guide roller and the vertical guide roller realize relative sliding between the movable frame and the guide frame, and bear the weight of the loading head and all non-vertical load mass caused by loading deformation.

A displacement sensor is arranged at the head of the push rod of the lateral deviation oil cylinder; a load sensor is arranged between the guide frame and the loading oil cylinder

The invention provides a lateral deviation loading rolling experiment using the lateral deviation loading rolling device, which comprises the following specific processes:

the first step is as follows: and (4) mounting a test wheel. The test machine wheel is installed on a wheel shaft through a bearing, and the wheel shaft is fixedly installed on the U-shaped loading head. After the installation is finished, the surface of the inner ring of the locomotive bearing is contacted with a thermocouple, and the thermocouple is connected with a data collector through a lead; the tire temperature was measured using an infrared thermometer.

The second step is that: and (5) preparing for lateral deviation. And starting the lateral deviation loading rolling system, controlling the supporting oil cylinder to enable the supporting roller to contact the upper surface of the outer slide rail, and lifting the height of the movable frame by 50mm to enable the lower surface of the movable frame and the surfaces of the inner slide rail and the outer slide rail to bear a non-contact state.

The third step: the angle of the wheel slip angle alpha is determined. The slip angle is the slip angle of the aircraft. The slip angle α is 0 to 20 °.

The fourth step: and controlling the side deviation oil cylinder to enable the movable frame to deflect around the swinging shaft along the outer sliding rail track, so that an included angle between a radial horizontal line of the machine wheel and the radial direction on the horizontal plane of the drum wheel is adjusted from 0 degree to 12 degrees, and the angle feedback is measured by an angle sensor arranged on the swinging shaft. After the side deflection angle of the machine wheel is adjusted to the proper position, the supporting oil cylinder is controlled to unload, the movable frame is lowered, and the bottom of the movable frame is respectively contacted with the upper surfaces of the inner slide rail and the outer slide rail until the supporting roller leaves the upper surface of the outer slide rail; and the movable frame and the guide rail are respectively fastened by using the outer slide rail fastening screw rod and the inner slide rail fastening screw rod.

The fifth step: and adjusting the test wheel to a loading critical state. And controlling the loading oil cylinder to push the guide frame to move towards the drum wheel along the movable frame at the speed of 1mm/s, so that the circumferential surface of the test wheel is contacted with the circumferential surface of the static drum wheel. And zeroing the load sensor, and recording the current position of the piston of the oil cylinder as the initial position of the airplane wheel. The position state of the test wheel is the loaded critical state position.

And a sixth step: and determining the roll parameters of the cornering loading.

The loading test parameters comprise: the working pressure output by the oil cylinder and the test load of the test bearing. Wherein:

the working pressure output by the oil cylinder is determined by the formula (1):

in the formula: d is the inner diameter of the hydraulic cylinder and the unit is m; f is the thrust of the hydraulic cylinder, and the unit is N; p is the working pressure in MPa.

Radial load F of test bearing_rDetermined by equation (2):

F_r＝F×cosα (2)

axial load F of test bearing_αDetermined by equation (3):

F_α＝F×sinα (3)

the seventh step: the rolling radius of the tire under rated load is measured.

The lateral deviation loading rolling system carries out lateral deviation loading rolling; and the loaded load is recovered through a load sensor, and the control system performs PID closed-loop control on the loaded load. The side-bias loading rolling system oil cylinder pushes the guide frame, so that wheels on the U-shaped loading head are pushed to load the surface of the drum wheel. When the loading load reaches a rated load value, taking the current oil cylinder piston position as a rated load loading position and recording the coordinate of the rated load loading position, taking the current tire temperature as a tire initial temperature value and recording the initial temperature value, and taking the current wheel bearing temperature value as a bearing initial temperature value and recording the bearing initial temperature value.

Determining the tire compression under rated load:

and (4) setting the tire compression amount s under the rated load as the wheel initial position value-the rated load loading position value. And the initial position value of the airplane wheel and the loading position value of the rated load are both obtained through actual measurement.

Determining the rolling radius r of the tire:

tire rolling radius r is wheel diameter-tire compression s under rated load

And controlling the load of the loading oil cylinder according to the obtained tire compression amount and the tire rolling radius r under the rated load, so that the airplane wheel is in the loading critical state of the fifth step.

Eighth step: simulating the aircraft speed.

And when the speed of the airplane is simulated, starting a driving system to enable the drum wheel to rotate at a specified speed so as to simulate the runway, wherein the simulated runway simulates the runway through the outer circular surface of the drum wheel, and the speed of the airplane is simulated through the relative motion mode of the surface of the drum wheel and the wheel.

According to the principle that the linear velocity of the wheel is the same as that of the drum wheel, obtaining a formula (4):

tire rolling radius r × pi × 2 × wheel rotation speed ═ drum diameter × pi × drum rolling speed (4)

The drum roll rate is determined by this equation (4). And when the rolling radius r of the tire, the rotating speed of the wheel, the diameter of the drum and the rolling speed of the drum are determined, the drum is driven by a motor to reach the rolling speed of the drum.

In simulating the aircraft speed, a drive system is activated such that the drum rotates at a prescribed speed to simulate an aircraft runway. Aircraft speed is simulated by relative movement of the drum surface and the wheel surface.

The ninth step: and (4) carrying out a rolling test under the lateral bias loading. And controlling a loading oil cylinder, wherein the oil cylinder pushes the guide frame to move along the guide wheel of the movable frame, so that the airplane wheel is loaded to the surface of the drum wheel, and the airplane wheel passively rotates to a rated test rotating speed under the action of friction force. The loading load needs to be loaded from 0 to the rated test load within 0.3 s.

A constant speed and constant load maintaining stage: when the load of the test bearing reaches 275KN and the rotating speed reaches 50km/h, the load and the rotating speed are maintained for carrying out a rolling test. The load, rotational speed, wheel bearing temperature, tire temperature and wheel position curves in the rollover test were recorded at a rate of 10Hz sampling rate.

And finishing the side deflection loading rolling test of the airplane wheel.

The invention relates to an aircraft wheel sideslip loading rolling device which is used for simulating a working condition test of a wheel during aircraft crosswind landing and is also suitable for a resistance loading system in an aircraft wheel acceleration fatigue test.

The loading mechanism adopts an integral frame structure, has large bearing capacity, has the maximum test load reaching 50T which is 2.5 times that of the existing test equipment, adopts CATIA three-dimensional forming design for ensuring the design safety of a test bed, assists in finite element strength calculation and analysis, and ensures mechanical design strength; as a guide frame for loading, a loading bracket supporting roller, an upper limit roller, a left limit roller and a right limit roller are arranged on the frame, the moving mode between the frame and the movable frame is a guide roller rolling motion mode distributed between the movable frame and the guide frame, the moving resistance is reduced, the current 0.5KN is improved from the 5KN required by the traditional guide rail type transmission mode, the defect that the load deviation is caused by overlarge resistance in the traditional guide rail type loading is overcome, and the reliability of a test bed and the reliability of test parameters are improved. In addition, the traditional loading device has lever benefit due to the stress of the guide rail, is limited in strength, has the limit load of 140KN, and greatly improves the capability of a rack for bearing axial load by a force transmission mode of 4 groups of guide wheels on four surfaces of a guide frame.

Because the improvement of the loading device, the lateral loading force which can be borne by the whole body is improved, and the lateral deviation angle is improved from the original lateral deviation limit of 15 degrees to the existing lateral deviation limit angle of 20 degrees. The test device is the first sideslip loading and rolling device which meets the requirement of a sideslip loading and rolling test of the airplane wheel of the large-scale transport plane in China, and is also the first test device which has dynamic heavy load life loading of the airplane wheel above 500KN in China.

The invention can realize the lateral deviation swinging of the lateral deviation loading rolling device of the fatigue life test bed of the airplane wheel by using a simple driving device, overcomes the harsh requirements brought by the manual operation of pulling the lateral deviation loading rolling system by a traditional crane to swing back and forth to adjust the angle and the defects of errors of the swinging angle, adopts a ball shaft structure as the circle center, uses a supporting oil cylinder at the tail part to reduce the resistance, uses a hydraulic cylinder to drag the lateral deviation, uses an angle sensor to carry out closed-loop control to realize the accurate positioning of the deviation angle, improves the accuracy from the original +/-1 degree to the present +/-0.1 degree, reduces the labor intensity of workers, increases the operation safety of equipment, provides a reliable and convenient test device for researching the airplane wheel and the tire with better performance, and can realize the lateral deviation rolling test and the accelerated life test of all the airplane wheels of military airplanes and civil airplanes under the specified conditions, the lateral-bias loading rolling device has the characteristics of low experimental cost and easiness in implementation, and is simple and feasible.

Three fatigue life test benches for aircraft wheels in comparison:

drawings

Fig. 1 is a top view of the present invention.

Fig. 2 is a front view of fig. 1.

Fig. 3 is a cross-sectional view of fig. 2.

FIG. 4 is a schematic view showing the positions of the swing shaft and the drum

FIG. 5 front view of the truck

FIG. 6 is a top view of FIG. 5

FIG. 7 is a schematic view of the construction of the swing shaft

FIG. 8 is a schematic view of the structure of the inner race of the bearing

FIG. 9 is a schematic view of the structure of the outer ring of the bearing

FIG. 10 is a side cross-sectional view of the connection reinforcement plate

FIG. 11 is a front sectional view of the connection reinforcing plate

FIG. 12 is a top view of the connection reinforcement plate

FIG. 13a is a schematic view of the structure of the guide frame

FIG. 13B is a schematic view of the section B-B in FIG. 13a

FIG. 13c is a top view of FIG. 13a

Fig. 13d is a schematic view of section a-a in fig. 13 a.

Fig. 14a is a schematic structural diagram of an interposer.

Fig. 14b is a left side view of fig. 14 a.

Fig. 15a is a schematic structural view of a U-shaped loading head.

Fig. 15b is a side view of fig. 15 a.

Fig. 16a is a schematic view of the structure of the guide wheel.

Fig. 16b is a side view of fig. 16 a.

Fig. 17a is a schematic structural view of the movable frame.

Fig. 17b is a side view of fig. 17 a.

Fig. 18a is a schematic structural view of the inner slide rail.

Fig. 18b is a left side view of fig. 18 a.

Fig. 19a is a schematic structural view of the outer slide rail.

Fig. 19b is a left side view of fig. 19 a.

Fig. 20a is a schematic view of the structure of the cylinder block of the loading cylinder.

Fig. 20b is a side view of fig. 20 a.

Fig. 20c is a top view of fig. 20 a.

In the figure: 1. a drum; 2. a main shaft; 3. a bearing seat; 4. a substrate assembly; 5. a bogie; 6. a machine wheel; 7. a wheel axle; 8, a U-shaped loading head; 9. a guide frame; 10. a movable frame; 11. loading an oil cylinder; 12. a lateral guide roller; 13. an outer slide rail; 14. an inner slide rail; 15. a lateral deviation oil cylinder; 16. a support cylinder; 17. a screw is fastened on the outer slide rail; 18. a screw is fastened on the inner slide rail; 19. a load sensor; 20. a vertically oriented guide roller; 21. a universal head; 22. an adapter plate; 23. a support roller; 24. connecting the reinforcing plate; 25. a swing shaft; 26. a bearing outer race; 27. a bearing inner race; 28. a retainer ring; 29. a gasket; 30. a bearing cap; 31. a support tab; 32. a steering frame mounting plate; 33. a floor sheathing panel; 34. perpendicular extension line of the central line of the swinging shaft.

Detailed Description

The embodiment is a certain type of airplane wheel side deviation test loading device.

The invention discloses an airplane wheel sideslip test device, which comprises a drum wheel 1, a main shaft 2, a bearing seat 3, a substrate assembly 4, a steering frame 5, an airplane wheel 6, an axle 7, a U-shaped loading head 8, a guide frame 9, a movable frame 10, loading

oil cylinders

11, 12, lateral guide rollers, an outer side sliding rail 13, an inner side sliding rail 14, a sideslip oil cylinder 15, a supporting oil cylinder 16, an outer sliding rail fastening screw 17, an inner sliding rail fastening screw 18, a load sensor 19 and a vertical guide roller 20. Wherein:

the main shaft 2 is mounted on the upper surface of the base plate assembly 4 through a bearing. The drum is mounted on the main shaft and is free to rotate. One end of the steering frame 5 is connected with the inner side surface of the substrate assembly, and the other end of the steering frame is fixedly connected with one side surface of the movable frame 10. An angular displacement sensor is arranged on a steering shaft of the bogie and is used for being matched with the side deviation swinging oil cylinder to ensure the accurate positioning of the side deviation angle of the movable loading head. The U-shaped loading head 8 is fixed in the frame of the steering frame; in the frame of the U-shaped loading head there is a rotating shaft 7 for mounting the wheel 6. The central line of the rotating shaft is parallel to the central line of the main shaft 2.

The outer slide rail 13 and the inner slide rail 14 are located on one side of the bogie frame 5, and are parallel to each other. One end of the movable frame 10 is provided with a connecting lug, and after the movable frame moves to the proper position, the movable frame and the outer slide rail are fixed by an outer slide rail fastening screw rod 17 penetrating through the connecting lug; the other end of the movable frame is also provided with a connecting lug, and when the movable frame moves to the proper position, the movable frame and the inner side sliding rail are fixed by an inner sliding rail fastening screw 18 penetrating through the connecting lug; the positioning of the movable frame is realized through fixed connection. A support roller 23 is arranged on the upper surface of the outer side slide rail; the supporting roller is installed on the lower surface of the supporting cylinder 16, and the upper end of the supporting cylinder is fixedly connected with the supporting lug 31 on the lower surface of the movable frame 10.

The movable frame 10 is a platform for mounting a movable loading part, is flatly placed on a slide rail, can rotate around the axis of a swinging shaft 25 in a base plate assembly along with a bogie, and is a stress member for the vertical loading and the lateral offset loading rolling of an airplane wheel. The movable frame force-bearing main body is 4 rectangular cold-bending hollow section steel columns with the specification of 400X200-12, the middle part and the upper part of the bottom of each steel column are welded by channel steel with the specification of 200X70-9 to form a frame body, and channel steel with different specifications is used as a ribbed plate for reinforcement at the main force-bearing part. The middle part of the movable frame is provided with a guide frame, and one end of the guide frame, which is close to the wheel, is used for installing a bogie.

Two groups of vertical guide rollers 20 are respectively arranged on the upper surface and the lower surface in the movable frame through connecting plates, and two groups of lateral guide rollers 12 are respectively arranged on the two side surfaces in the movable frame through connecting plates. The guide frame 9 is placed in the middle of the inside of the movable frame 10 and supported by the vertical guide rollers and the lateral guide rollers such that the vertical guide rollers and the lateral guide rollers are slidably engaged with the surface of the guide frame to reduce frictional resistance of the guide frame during movement. The height of the guide frame 9 is equal to that of the loading head, and one end of the guide frame is fixedly connected with one end of the U-shaped loading head 8. The wheel 6 is mounted on an axle 7 at the other end of the U-shaped loading head.

The surface of the movable frame, which is close to one side of the drum wheel 1, is fixedly connected with one end of the steering frame 5 through a steering frame mounting plate 32; the other end of the bogie frame is axially connected to the swing shaft in the base plate assembly 45 by a ball axle.

The base plate assembly 4 includes a swing shaft 25, a bearing outer ring 26, a bearing inner ring 27, a ground shroud 33, a retainer ring 28, and a connection reinforcing plate 24. The swinging shaft penetrates through the through hole in the floor covering plate, one end of the swinging shaft is positioned on the upper surface of the floor covering plate, and the other end of the swinging shaft is positioned on the lower surface of the floor covering plate. The connection reinforcing plate 24 is positioned on the upper surface of the floor covering plate and is sleeved on the swinging shaft; the connection reinforcement plate is fixed by a retainer ring 28. The bearing is positioned on the lower surface of the floor covering plate, is sleeved on the swinging shaft through a gasket 29, and sequentially comprises a bearing inner ring 27, a bearing outer ring 26 and a bearing cover 30 from inside to outside. The gasket 29 is a gasket of conventional technology.

The lower end face of the swinging shaft 25 is provided with a positioning boss, the middle part is used for mounting a bearing inner ring, and the outer circumferential surface of the upper end head is provided with a screw hole for mounting a check ring 28.

The bearing outer ring 26 and the bearing inner ring 27 form a set of joint bearing. The inner radius of the bearing outer ring 26 is 210mm, and the outer radius of the bearing inner ring is 210 mm; the diameter of an inner hole of the bearing inner ring 27 is 240mm, the outer diameter of the middle part of the swinging shaft 25 is 240mm, and the outer diameter of the end with the screw hole is 190 mm; the outer circumferential surface of the bearing inner ring is provided with a groove for filling lubricating grease. The upper end of the bearing outer ring is provided with a retainer ring of a boss.

The bearing cover 30 is a circular cover plate, and the outer edge of the upper surface of the bearing cover is provided with a boss, and fixing screw holes are uniformly distributed on the boss. The outer diameter of the bearing cover is the same as that of a bearing mounting seat of the bogie 5, and the inner diameter of the bearing cover is matched with a positioning spigot on the inner circle surface of the bearing mounting seat.

The U-shaped loading head 8 is a connecting piece for mounting the test wheel 6, as in the prior art. The U-shaped loading head 8 is made of a steel plate with the thickness of 20mm through bending and welding.

The outer side sliding rail 13 is formed by bending and welding steel plates, and the radius of the outer side sliding rail is 5000 mm. The upper surface of the outside slide rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm. A mounting hole for mounting the yaw cylinder 15 is formed in the surface of one end of the outer rail 13.

The inner slide rail 14 is also formed by bending and welding steel plates, and the radius of the inner slide rail is 3000 mm. The upper surface of the inner side slide rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm.

The drum wheel 1 is the prior art, the circumference is 7m, the outer circumferential surface of the drum wheel is used for simulating an airplane runway, and in a loading test, the outer circumferential surface of the drum wheel is in contact with the outer circumferential surface of the wheel under the action of a load to form a pair of friction pairs. The drum wheel is arranged on the main shaft; the two ends of the main shaft are respectively arranged on the bearing seats, so that the drum wheel can freely rotate between the bearing seats at the two ends.

The bogie 5 is a U-shaped frame structure, the opening end of the bogie is used for connecting a connecting plate of the movable frame, the other end of the bogie is a bearing mounting seat, and the inner surface of the bearing mounting seat is a spherical surface matched with the outer surface of the bearing outer ring. The bearing mount is mounted on the bearing cup 26 and provides a rotational fit therebetween. When the sideslip oil cylinder works, the bogie can horizontally rotate 20 degrees towards two sides around the central line of the swinging shaft 25 respectively, so that the movable frame 10 is driven to sideslip and displace, the wheel is driven to sideslip by the same angle, and a sideslip angle is formed between the surface of the wheel and the surface of the drum wheel; when the support cylinder 16 is operated, the bogie can move up and down along the outer circumferential surface of the bearing outer race, so that the movable frame can move up by 50 mm.

The perpendicular extension 34 of the centerline of the axis of oscillation is tangential to the point A of the drum's outer circumferential surface closest to the wheel.

The adapter plate 22 is cylindrical, screw holes for mounting the U-shaped loading head 8 are uniformly distributed on the end face of the small outer diameter end of the adapter plate, a connecting flange is arranged at the end head of the other end of the adapter plate, and the screw holes for fixing the guide frame 9 are uniformly distributed on the connecting flange. The small outer diameter end of the adapter plate is respectively matched with the through hole at one end of the U-shaped loading head and the through hole at one end of the guide frame 9, and during implementation, the small outer diameter end of the adapter plate sequentially penetrates through the through hole of the guide frame 9 and the through hole of the U-shaped loading head and is fixed by screws. One end of the load sensor is mounted on the end face of the other end of the adapter plate 22 by a screw.

The vertical guide roller 20 has a double-wheel structure including a roller frame, a roller shaft, and a roller. The roller carrier is a double-support, and two roller mounting grooves are arranged on the roller carrier side by side. The two roller shafts are arranged on the upper end surface of the roller frame side by side and are fixed through roller shaft pressing plates. Each roller is mounted on the roller shaft through a bearing.

The lateral guide roller has the same structure as the vertical guide roller 20.

The number of the lateral guide rollers 12 is 8, and the lateral guide rollers are divided into two groups; the two groups of lateral guide rollers are symmetrically and horizontally arranged on the inner surface of the movable frame 10. The number of the vertical guide rollers 20 is also 8, and the vertical guide rollers are divided into two groups; the two sets of vertical guide rollers are symmetrically and vertically installed on the inner side surface of the movable frame 10. The relative sliding between the movable frame 10 and the guide frame 9 is realized by the lateral guide rollers and the vertical guide rollers 20, and the weight of the loading head and all non-vertical load mass caused by loading deformation are borne.

And 2 support oil cylinders 16 are respectively arranged on the end surfaces of the movable frames, which are positioned on the outer guide rails. The side deviation oil cylinder 15 adopts a three-stage oil cylinder, an angular displacement sensor is arranged at the head of a push rod of the side deviation oil cylinder 15, and the deviation loading angle is realized by controlling the stroke of the push rod of the oil cylinder. The supporting oil cylinder and the side deviation oil cylinder are conventional oil cylinders.

The load sensor is arranged between the guide frame and the loading oil cylinder, one end of the load sensor is hinged with an oil cylinder piston rod through a universal head, and the other end of the load sensor is fastened with the guide frame through a bolt. The load cell is subjected to axial thrust and tension. Lateral force components in all directions caused by equipment installation errors or frame loading deformation are transmitted to the roller from the frame and then transmitted to the base. The load sensor is arranged between the oil cylinder and the guide frame, bears pure thrust and tension, and transmits lateral component force caused by installation and deformation to the roller assembly through the frame and then transmits the lateral component force to the base.

In practice, the drum 1 is fixed on the main shaft by double flat keys, one side is positioned by a retaining shoulder on the main shaft, and the other side is directly contacted with the inner ring of the bearing through the shaft sleeve. The main shaft is supported and rotated by means of a bearing support and a bearing. The bracket of the bearing seat is fixed on the base plate through the bolt of the M48.

The lateral deviation swing oil cylinder adopts a three-stage oil cylinder, the total length of the oil cylinder is 1300mm when the push rod is in a retraction state, the maximum extension stroke of the push rod is 2100mm, and the axial thrust is 4000 kg. An angular displacement sensor is arranged at the head of the side-offset oil cylinder push rod, and the offset load angle is realized by controlling the stroke of the oil cylinder push rod.

The supporting oil cylinder is a conventional oil cylinder with 50mm of stroke, 180mm of cylinder diameter and 100mm of rod diameter, and a hydraulic system meets the requirements of the test bed under the working pressure of 16 Mpa.

Before the lateral deviation loading rolling test, starting an oil pump, returning the position of an oil cylinder to an initial position, loosening fastening nuts positioned on the outer sides of 4 stand columns of a movable loading frame, controlling two supporting oil cylinders to output thrust, and lifting the movable loading part by 5-15 mm by taking a rotating shaft of a moving frame positioned below a drum wheel as a fulcrum under the action of the supporting oil cylinders so as to enable the movable frame to leave a supporting surface of a slide rail; and controlling the deflection oil cylinder to enable the movable frame to rotate by an angle required by the test along the center of the rotating shaft of the movable frame under the action of the lateral deflection oil cylinder, then controlling the supporting oil cylinder rod to be retracted, enabling the movable loading part to fall to the supporting surface of the sliding rail, and locking the fastening nut to complete the lateral deflection movement action of the movable loading head.

In operation, one end face of the bogie 5 is mounted on the movable frame 10 through a bogie mounting plate 32, one end of a bearing mounting seat is mounted with a bearing outer ring 26, a bearing inner ring 27 is mounted inside the bearing outer ring 26, the swinging shaft 25 sequentially passes through the bearing inner ring 27, a gasket, the base plate assembly 4 and the connection reinforcing plate 24, wherein the connection reinforcing plate 24 is fixed on the base plate assembly 4 through screw holes at two ends thereof, and the baffle ring 28 is fixed with one end face of the swinging shaft 25 through screw holes at an end face thereof. The bearing cover 30 is fixed on the bearing mounting seat of the bogie 5 through the screw holes uniformly distributed on the outer ring, so that the bearing is blocked. The bogie 5 can rotate around the swinging shaft on the horizontal plane through the bearing, the vertical loading load and the side load acting on the machine wheel are transmitted to the bogie 5 through the movable frame, the bogie 5 acts on the swinging shaft 25 through the bearing inner ring 27, the swinging shaft 25 is transmitted to the base plate assembly 4 through the connecting reinforcing plate, and the dragging system is arranged on the base plate assembly 4, so that the reaction force to the resultant force of the loads is formed and counteracted. Because the impact load born by the airplane wheel is quite large, the common ball bearing has a certain play and is easy to cause fatigue damage, and the structural design can bear large load for a long time without causing permanent deformation. When the movable frame needs to move and deflect, the supporting oil cylinder 16 jacks up the tail part of the movable frame, so that the bogie 5 surrounds the spherical center of the bearing inner ring 26 and forms a certain included angle with the horizontal plane in the vertical direction. The ball bearing can complete the lateral deflection of the movable frame around the horizontal plane of the swinging shaft 25, and can also enable the bogie to form a certain included angle around the circle center of the bearing and the horizontal plane when the movable frame moves.

In this embodiment, the guide frame 9 is formed by welding channel steel, and is matched with the upper surface, the lower surface and two side surfaces of the fixed frame through the guide rollers, so as to realize the horizontal movement of the guide frame. And a screw hole for mounting the U-shaped loading head 8 is formed in the middle of one end of the guide frame. The geometric central position of the guide frame 9 is a loading oil cylinder 11, the loading oil cylinder 11 is arranged on an oil cylinder support, and the oil cylinder support 11 is fixedly arranged on a cross beam of the movable frame through screw holes on two end faces of the oil cylinder support. The oil cylinder support is formed by welding channel steel and reinforcing the channel steel by using a rib plate, and the thrust of the loading oil cylinder 11 is transmitted to the movable frame, which is a conventional technology. A piston rod of the loading oil cylinder 11 is connected with a universal head 21, and a load sensor 19 is connected to the universal head 21; the load sensor 19 is fixed by the adapter plate 22, the loading head and the guide frame 9.

The embodiment also provides a method for carrying out a yaw loading and rolling test on a certain airplane wheel by using the yaw loading and rolling device. The sideslip fatigue rolling test is to simulate the use condition of the airplane wheel during the sideslip landing of the airplane, and the service life condition of the airplane wheel under the condition includes whether the tire of the airplane wheel is burst or bulge under rated test load and speed, whether the airplane wheel has cracks or unrecoverable deformation and the like, and a tire temperature change curve and an airplane wheel bearing temperature change curve under the condition are obtained.

During the test, the load borne by the single airplane wheel of the airplane type when the airplane is fully loaded is 275 KN. In this embodiment, the diameter of the piston of the selected loading hydraulic cylinder is 180mm, the diameter of the piston rod is 125mm, the diameter of the wheel is 1200mm, and the diameter of the drum wheel is 2228 mm.

The adopted three-phase alternating current variable frequency speed regulating asynchronous motor 1 is a quadrupole motor with the power of 250KW and the rotating speed of 1490 rpm.

The specific process of this embodiment is:

The second step is that: and (5) preparing for lateral deviation. The outer rail fastening screw 17 and the inner rail fastening screw 18 are loosened. And starting the lateral deviation loading rolling system, controlling the supporting oil cylinder to enable the supporting roller to contact the upper surface of the outer slide rail, and lifting the height of the movable frame by 50mm to enable the lower surface of the movable frame and the surfaces of the inner slide rail and the outer slide rail to bear a non-contact state.

The third step: the angle of the wheel slip angle alpha is determined. The slip angle is the slip angle of the aircraft. The slip angle α is 0 to 20 °, and in the present embodiment, the slip angle α is 12 °.

The fourth step: and controlling the side deviation oil cylinder to enable the movable frame to deflect around the swinging shaft along the outer sliding rail track, so that an included angle between a radial horizontal line of the machine wheel and the radial direction on the horizontal plane of the drum wheel is adjusted from 0 degree to 12 degrees, and the angle feedback is measured by an angle sensor arranged on the swinging shaft. After the side deflection angle of the machine wheel is adjusted to the proper position, the supporting oil cylinder is controlled to unload, the movable frame is lowered, and the bottom of the movable frame is respectively contacted with the upper surfaces of the inner slide rail and the outer slide rail until the supporting roller leaves the upper surface of the outer slide rail; the movable frame and the guide rail are fastened by an outer slide rail fastening screw 17 and an inner slide rail fastening screw 18, respectively.

And a sixth step: and determining the roll parameters of the cornering loading.

Radial load F of test bearing_rDetermined by equation (2):

F_r＝F×cosα (2)

axial load F of test bearing_αDetermined by equation (3):

F_α＝F×sinα (3)

in the embodiment, the diameter of the piston of the hydraulic cylinder is 180mm, the working pressure output by the oil cylinder is 10.81MPa, the airplane load is 275KN, the radial load of the test bearing is 269KN, and the axial load is 57.2 KN.

The seventh step: the rolling radius of the tire under rated load is measured.

The lateral deviation loading rolling system carries out lateral deviation loading rolling; and the loaded load is recovered through a load sensor, and the PID closed-loop control is carried out on the loaded load through a control system by adopting a conventional method. The side-bias loading rolling system oil cylinder pushes the guide frame, so that wheels on the U-shaped loading head are pushed to load the surface of the drum wheel. When the loading load reaches a rated load value, taking the current oil cylinder piston position as a rated load loading position and recording the coordinate of the rated load loading position, taking the current tire temperature as a tire initial temperature value and recording the initial temperature value, and taking the current wheel bearing temperature value as a bearing initial temperature value and recording the bearing initial temperature value.

Determining the tire compression under rated load:

Determining the rolling radius r of the tire:

tire rolling radius r is wheel diameter-tire compression s under rated load

Eighth step: simulating the aircraft speed.

In this embodiment, the test speed of the wheel is 50km/h, the diameter of the wheel is phi 1200mm, and the diameter of the drum is phi 2228 mm. According to the principle that the linear velocity of the wheel is the same as that of the drum wheel, obtaining a formula (4):

In the test process, if abnormal phenomena of vibration and noise caused by the airplane wheel occur, or the temperature of a bearing and a tire suddenly increases, or other abnormal phenomena such as tire burst occur, the airplane wheel is directly unloaded, whether the airplane wheel has cracks or deformation, whether the tire is bulged or leaked or not is detected according to a conventional method after the airplane wheel is unloaded, and recorded data is analyzed by the conventional method to judge whether the airplane wheel is up to the service life or not. And finishing the side deflection loading rolling test of the airplane wheel.

Claims

1. A lateral deviation rolling loading device of an aircraft wheel fatigue test bed is characterized by comprising a drum wheel (1), a main shaft (2), a substrate assembly (4), a steering frame (5), an axle (7), a U-shaped loading head (8), a guide frame (9), a movable frame (10), a loading oil cylinder (11), an outer side sliding rail (13), an inner side sliding rail (14), a lateral deviation oil cylinder (15), a supporting oil cylinder (16), a load sensor (19) and a vertical direction guide roller (20); wherein: the main shaft (2) is arranged on the upper surface of the substrate assembly (4); the drum wheel is arranged on the main shaft and can rotate freely; one end of the steering frame (5) is connected with the inner side surface of the substrate assembly, and the other end of the steering frame is fixedly connected with one side surface of the movable frame (10); an angular displacement sensor is arranged on a steering shaft of the bogie and is used for being matched with a lateral deviation swinging oil cylinder to ensure the accurate positioning of the lateral deviation angle of the movable loading head; the U-shaped loading head (8) is fixed in the frame of the steering frame; a rotating shaft (7) for mounting the wheel is arranged in the frame of the U-shaped loading head; the central line of the rotating shaft is parallel to the central line of the main shaft (2); the outer side sliding rail (13) and the inner side sliding rail (14) are both positioned on one side of the steering frame (5), and the outer side sliding rail and the inner side sliding rail are parallel; the upper surface of the outer slide rail is provided with a supporting roller (23); a lateral deviation oil cylinder (15) is arranged on the surface of one end of the outer side sliding rail (13); two supporting oil cylinders (16) are arranged on the end surface of the movable frame at the end of the outer guide rail; the loading oil cylinder (11) is positioned at the geometric center of the guide frame (9) and is fixed on a cross beam of the movable frame; the surface of the movable frame, which is close to one side of the drum wheel (1), is fixedly connected with one end of the steering frame (5); the other end of the steering frame is connected with a swinging shaft (25) in the base plate assembly through a ball shaft; the guide frame (9) is placed in the middle of the movable frame and is in sliding fit with the surface of the guide frame through the vertical guide roller and the lateral guide roller so as to reduce the friction resistance of the guide frame during movement.

2. The sidesway roll loading device of the aircraft wheel fatigue test bed of claim 1 is characterized in that two groups of vertical guide rollers (20) are respectively installed on the upper surface and the lower surface in the movable frame (10), and two groups of lateral guide rollers (12) are respectively installed on the two side surfaces in the movable frame through connecting plates; the guide frame (9) is placed in the middle of the movable frame (10) and is supported by the vertical guide rollers and the lateral guide rollers, so that the vertical guide rollers and the lateral guide rollers are in sliding fit with the surface of the guide frame; the height of the guide frame (9) is equal to that of the loading head, and one end of the guide frame is fixedly connected with one end of the U-shaped loading head (8); the wheel 6 is arranged on a wheel shaft (7) positioned at the other end of the U-shaped loading head; one end of the movable frame (10) is provided with a connecting lug fixed with the outer side sliding rail; and the other end of the movable frame is also provided with a connecting lug fixed with the inner side slide rail.

3. The sidesway roll loading device of an aircraft wheel fatigue test stand according to claim 1, characterized in that said base plate assembly (4) comprises a swing shaft (25), a ground shroud plate (33), a retainer ring (28) and a connecting reinforcement plate (24); the swinging shaft penetrates through the through hole on the floor sheathing board, one end of the swinging shaft is positioned on the upper surface of the floor sheathing board, and the other end of the swinging shaft is positioned on the lower surface of the floor sheathing board; the connecting reinforcing plate (24) is positioned on the upper surface of the floor covering plate and is sleeved on the swinging shaft; fixing the connection reinforcing plate by a retainer ring (28); the bearing is positioned on the lower surface of the floor covering plate and is sleeved on the swinging shaft.

4. The yawing and rolling loading device of the aircraft wheel fatigue test bed of claim 1, wherein the radius of the outer side slide rail (13) is 5000 mm; the upper surface of the outer side sliding rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm; the surface of one end of the outer side sliding rail (13) is provided with a mounting hole for mounting a lateral deviation oil cylinder (15); the radius of the inner side sliding rail (14) is 3000 mm; the upper surface of the inner side slide rail is a working surface, a groove-shaped rail is arranged on the working surface, and the width of the inner surface of the groove-shaped rail is 55 mm.

5. The yawing rolling loading device of the aircraft wheel fatigue testing stand of claim 1, wherein the bogie (5) is a U-shaped frame structure, the open end of the bogie is used for connecting a connecting plate of a movable frame, the other end of the bogie is a bearing mounting seat, and the inner surface of the bearing mounting seat is a spherical surface matched with the outer surface of a bearing outer ring; the bearing mounting seat is sleeved on the bearing outer ring 26 and enables the bearing outer ring and the bearing outer ring to be in running fit; when the sidesway oil cylinder works, the bogie can horizontally rotate 20 degrees towards two sides around the central line of the swinging shaft (25) respectively, so that the movable frame (10) is driven to sidesway and displace, and further the wheel is driven to sidesway by the same angle, and a sidesway angle is formed between the surface of the wheel and the surface of the drum wheel; when the supporting oil cylinder (16) works, the bogie can move up and down along the outer circumferential surface of the bearing outer ring, so that the movable frame can move up by 50 mm; the vertical extension line (34) of the central line of the swinging shaft is tangent to the point A of the drum wheel outer circle surface closest to the wheel.

6. The sidesway roll loading device of the aircraft wheel fatigue test bed of claim 1, characterized in that said vertical guide roller (20) is a double wheel structure comprising a roller frame, a roller shaft and a roller; the roller carrier is a double-bracket, and two roller mounting grooves are arranged on the roller carrier side by side; the two roller shafts are arranged on the upper end surface of the roller frame side by side and are fixed through roller shaft pressing plates; each roller is arranged on the roller shaft through a bearing; the lateral guide roller and the vertical guide roller (20) have the same structure.

7. The sidesway roll loading device of the aircraft wheel fatigue test bed of claim 1, characterized in that said lateral guide rollers (12) have 8 and are divided into two groups; the two groups of lateral guide rollers are symmetrically and horizontally arranged on the inner surface of the movable frame (10); the number of the vertical guide rollers (20) is also 8, and the vertical guide rollers are divided into two groups; the two groups of vertical guide rollers are symmetrically and vertically arranged on the inner side surface of the movable frame (10); the lateral guide roller and the vertical guide roller (20) realize relative sliding between the movable frame (10) and the guide frame (9), and bear the weight of the loading head and all non-vertical load mass caused by loading deformation.

8. The yawing rolling loading device for the aircraft wheel fatigue test bed of claim 1, wherein a angular displacement sensor is arranged at the head part of the yawing oil cylinder push rod; a load sensor (19) is arranged between the guide frame and the loading cylinder.

9. The method for carrying out the yawing and rolling loading experiment by using the yawing and rolling loading device of claim 1, which is characterized by comprising the following specific steps:

the first step is as follows: mounting a test machine wheel; the test machine wheel is arranged on a wheel shaft through a bearing, and the wheel shaft is fixedly arranged on the U-shaped loading head; after the installation is finished, the surface of the inner ring of the locomotive bearing is contacted with a thermocouple, and the thermocouple is connected with a data acquisition unit through a lead; detecting the temperature of the tire by using an infrared thermometer;

the second step is that: preparing lateral deviation; starting the lateral deviation rolling loading system, controlling the supporting oil cylinder to enable the supporting roller to contact the upper surface of the outer slide rail, and lifting the height of the movable frame by 50mm to enable the lower surface of the movable frame and the surfaces of the inner slide rail and the outer slide rail to bear a non-contact state;

the third step: determining the angle of the side slip angle alpha of the airplane wheel; the sideslip angle is the sideslip angle of the airplane; the side deflection angle alpha is 0-20 degrees;

the fourth step: controlling a side deviation oil cylinder to enable the movable frame to deflect around the swinging shaft along the outer sliding rail track, adjusting an included angle between a radial horizontal line of the wheel and the radial direction on the horizontal plane of the drum wheel from 0 degree to 12 degrees, and measuring the angle feedback through an angle sensor arranged on the swinging shaft; after the side deflection angle of the machine wheel is adjusted to be in place, controlling the support oil cylinder to unload, and lowering the movable frame to enable the bottom of the movable frame to be respectively contacted with the upper surfaces of the inner slide rail and the outer slide rail until the support roller leaves the upper surface of the outer slide rail;

the fifth step: adjusting the test machine wheel to a loading critical state; controlling a loading oil cylinder to push a guide frame to move towards a drum wheel along a movable frame at the speed of 1mm/s, so that the circumferential surface of the test wheel is contacted with the circumferential surface of the static drum wheel; zeroing the load sensor, and recording the current position of the piston of the oil cylinder as the initial position of the airplane wheel; at the moment, the position state of the test airplane wheel is the loaded critical state position;

and a sixth step: determining a lateral deviation rolling loading parameter; the loading test parameters comprise: the working pressure output by the oil cylinder and the test load of the test bearing; wherein:

the working pressure P output by the oil cylinder is determined by the formula (1):

in the formula: d is the inner diameter of the hydraulic cylinder and the unit is m; f is the thrust of the hydraulic cylinder, and the unit is N; p is the working pressure in MPa;

radial load F of test bearing_rDetermined by equation (2):

F_r＝F×cosα (2)

axial load F of test bearing_αDetermined by equation (3):

F_α＝F×sinα (3)

the seventh step: measuring the rolling radius of the tire under the rated load; the lateral deviation rolling loading system carries out lateral deviation rolling loading; the loaded load is recovered through a load sensor, and the control system performs PID closed-loop control on the loaded load; the side-deviation rolling loading system oil cylinder pushes the guide frame, so that wheels on the U-shaped loading head are pushed to load the surface of the drum wheel; when the loading load reaches a rated load value, taking the current oil cylinder piston position as a rated load loading position and recording the coordinate of the rated load loading position, taking the current tire temperature as a tire initial temperature value and recording the initial temperature value, and taking the current wheel bearing temperature value as a bearing initial temperature value and recording the bearing initial temperature value;

determining the tire compression under rated load:

the tire compression amount s under the rated load is equal to the wheel initial position value-the rated load loading position value; the initial position value of the airplane wheel and the loading position value of the rated load are both obtained through actual measurement;

determining the rolling radius r of the tire:

tire rolling radius r is wheel diameter-tire compression s under rated load

Controlling the load of the loading oil cylinder according to the obtained tire compression amount and the tire rolling radius r under the rated load, so that the airplane wheel is in a loading critical state in the fifth step;

eighth step: simulating the speed of the airplane; when the speed of the airplane is simulated, a driving system is started, so that the drum wheel rotates at a specified speed to simulate an airplane runway, the simulated airplane runway simulates the airplane runway through the outer circle surface of the drum wheel, and the speed of the airplane is simulated through the relative motion mode of the surface of the drum wheel and the airplane wheel;

Determining the drum roll speed through the formula (4); when the rolling radius r of the tire, the rotating speed of the wheel, the diameter of the drum and the rolling speed of the drum are determined, the drum is driven by a motor to reach the rolling speed of the drum;

starting a driving system when the speed of the airplane is simulated, so that the drum wheel rotates at a specified speed to simulate an airplane runway; simulating aircraft speed through relative movement of a drum wheel surface and a wheel surface;

the ninth step: performing a lateral deviation rolling loading test; controlling a loading oil cylinder to push a guide frame to move along a guide wheel of a movable frame, so that a wheel loads the surface of a drum wheel, and the wheel passively rotates to a rated test rotating speed under the action of friction force; loading load needs to be loaded from 0 to rated test load within 0.3 s;

a constant speed and constant load maintaining stage: when the load of the test bearing reaches 275KN and the rotating speed reaches 50km/h, maintaining the load and the rotating speed to carry out a rolling test; recording the curves of load, rotating speed, wheel bearing temperature, tire temperature and wheel position in a roll test at the speed of a 10Hz sampling rate;

and finishing the yaw rolling loading test of the airplane wheel.