CN100422711C - Helicopter rotor horizontal hinge bearing fatigue testing machine - Google Patents

Abstract

The invention discloses a helicopter rotor horizontal hinge bearing fatigue testing machine. An outer circular arc △-shaped guide rail (22) and an inner circular arc △-shaped guide rail (23) are fixedly connected to the arc-shaped frame of the support frame (2), and the short axis of the frame is also fixedly connected to the support frame (2) (16), on the frame minor axis (16), be connected with axle (15,17). Helicopter rotor horizontal hinge bearing (14) is installed on shaft (15), (17), and the bearing hole sleeve of small frame (24) is on the bearing (14); On the small frame (24), connect two load bearings respectively by ball hinge The hydraulic cylinders (3, 5), the loading hydraulic cylinder (3) are connected to the frame (2) through a ball joint, and the loading hydraulic cylinder (5) is connected to the H-shaped frame (1) through a ball joint. This fatigue testing machine can truly simulate the working load of the rotor axial hinge bearing and the real angular velocity and angular acceleration of the rotor through various loading methods in the fatigue test of the rotor horizontal hinge bearing, thereby replacing the helicopter rotor in the fatigue test. The invention greatly reduces the cost of the fatigue test of the axial hinge bearing of the rotor under the premise of ensuring the authenticity and reliability of the fatigue test of the axial hinge bearing of the rotor.

Description

Helicopter rotor horizontal hinge bearing fatigue testing machine

technical field

The invention relates to a fatigue testing machine for a helicopter rotor horizontal hinge bearing.

Background technique

Helicopter is a kind of rotorcraft, which is a vertical take-off and landing machine with rotor as its main source of lift. The force required for helicopter flight is generated by the rotation of the rotor. The axis of the rotor is close to the vertical, which generates an upward pulling force to overcome the weight of the helicopter. At the same time, the rotor can be manipulated by the control mechanism to generate forward, backward, left, and vertical directions. The right horizontal component force, therefore, the helicopter can take off and land vertically, hover in the air, and fly in all directions forward, backward, left, and right.

It can be seen that the rotor system is one of the most important parts of the helicopter, and the performance of the rotor system has a decisive impact on the flight safety, maneuverability, reliability and service life of the helicopter. The part of the rotor that bears the greatest alternating stress is the root of the rotor, where the stress concentration is the most serious. In order to reduce the stress concentration at the root of the rotor and improve the fatigue life of the rotor, three hinges are generally designed at the root of the helicopter rotor: axial hinge, horizontal hinge, and vertical hinge. Most of the three hinges of helicopters use rolling bearings. Both bear a large alternating load, and each bearing does not rotate for a full circle, but reciprocates at a high frequency and small angle, and its stress, working conditions, lubrication and other conditions are very poor. Among them, the horizontal hinge bearing is one of the most important supporting parts in the rotor system. Therefore, the scientific and accurate evaluation of the fatigue life of the rotor horizontal hinge bearing has an important impact on the design, use and maintenance of the helicopter rotor system and the entire helicopter, and the scientific and accurate evaluation of the fatigue life of the rotor horizontal hinge bearing is based on a large number of fatigue test.

In the past, the fatigue experiments of helicopter rotor horizontal hinge bearings mostly used to install the rotor horizontal hinge bearing directly in the rotor system, and make the rotor system rotate under various angular velocities and angular accelerations according to the flight process of a helicopter close to the real one. In order to accurately evaluate the fatigue life of the rotor horizontal hinge bearing, the sampling sample of the fatigue test must be large enough, that is, the number of groups of the horizontal hinge bearings for the fatigue test must be large enough, and the rotor used for the fatigue test of the rotor horizontal hinge bearing has to be used in the cross section. Long-term work under the effect of variable load; and the rotor used in the rotor horizontal hinge bearing fatigue test must be the real rotor of the helicopter, so that the experimental load of the rotor horizontal hinge bearing is close to the real load in the working process, and the fatigue life of the helicopter rotor is a certain Therefore, the rotor itself often suffers from fatigue damage during the experiment and must be replaced frequently. Because the manufacturing cost of the rotor is very high, this just makes the cost of the fatigue test of the rotor horizontal hinge bearing too large. At the same time, since the diameter of the helicopter rotor is generally between 20 meters and 40 meters, the fatigue test of the rotor horizontal angular bearing requires a large experimental site. In addition, because the moment of inertia of the helicopter rotor is very large, the starting and braking torque required to make it accelerate and decelerate is also very large, and must be driven by a high-power motor, so the energy consumption of the rotor horizontal hinge bearing fatigue test is also very large.

Contents of the invention

The purpose of the present invention is to provide a kind of fatigue testing machine of helicopter rotor horizontal hinge bearing, this fatigue testing machine can simulate the working load of rotor axial hinge bearing and the true angular velocity of rotor by various loading methods in the rotor horizontal hinge bearing fatigue experiment , angular acceleration and other parameters, thereby replacing the helicopter rotor in the fatigue test, it can greatly reduce the cost of the rotor axial hinge bearing fatigue test under the premise of ensuring the authenticity and reliability of the rotor axial hinge bearing fatigue test.

The technical solution adopted by the present invention to solve the technical problem is: an outer circular arc △-shaped guide rail and an inner circular arc △-shaped guide rail are fixedly connected to the arc-shaped frame of the supporting frame, and the short axis of the frame is also fixedly connected to the supporting frame , the shaft is fixedly connected to the short axis of the frame. The helicopter rotor horizontal hinge bearing is installed on the shaft, and the bearing hole of the small frame is sleeved on the bearing; two loading hydraulic cylinders are respectively connected to the small frame through a ball joint, one loading hydraulic cylinder is connected to the frame through a ball joint, and the other is loaded with hydraulic pressure. The cylinder is connected to the H-frame through a ball joint. Four short shafts are fixedly connected to the H-shaped frame, and each short shaft has a wheel with a V-shaped groove. The H-shaped frame is supported on the frame, and the H-shaped frame can reciprocate along the arc-shaped track of the frame. Two guide rods are fixedly connected to the small frame, and the guide rods are matched with the two guide holes on the H-shaped frame respectively, so that the H-frame and the small frame can move relative to each other, but cannot rotate relative to each other; between the H-shaped frame and the connecting rod Connected by a hinge, the connecting rod is connected with a slider with a nut through a hinge, the slider can make a reciprocating linear motion in the guide groove of the frame, and the output shaft of the servo motor is fixedly connected with the lead screw; the servo motor is connected through the lead screw, connecting rod, The H-shaped frame and the guide rod make the horizontal hinge bearing of the rotor generate high-frequency reciprocating swing.

Description of drawings

Fig. 1 is a structural schematic diagram of a helicopter rotor horizontal hinge bearing fatigue testing machine;

Fig. 2 is the A-A sectional view of the helicopter rotor horizontal hinge bearing fatigue testing machine;

Fig. 3 is a B-B sectional view of the helicopter rotor horizontal hinge bearing fatigue testing machine.

In Figure 1, 1. H-shaped frame, 2. Support frame, 3. Loading hydraulic cylinder, 4. First guide rod, 5. Loading hydraulic cylinder, 6. Second guide rod, 7. Guide groove, 8. Connecting Rod, 9. Slide block, 10. Lead screw, 11. Servo motor, 12. Short shaft, 13. Short shaft, 15. Upper half shaft, 16. Frame short shaft, 17. Lower half shaft, 18. Wheel, 19 .Short shaft, 20. Short shaft, 21. Wheel, 22. Outer arc △ guide rail, 23. Inner arc △ guide rail, 24. Small frame, 25. Wheel, 26. Wheel,

Detailed ways

Fig. 1 is an embodiment disclosed by the present invention, an outer circular arc △-shaped guide rail 22 and an inner circular arc △-shaped guide rail 23 are fixedly connected on the circular arc-shaped frame of the supporting frame 2, and an outer circular arc △-shaped guide rail 23 is fixedly connected on the supporting frame 2 Frame short shaft 16 is fixedly connected with upper half shaft 15 and lower half shaft 17 on frame short shaft 16 . Helicopter rotor horizontal hinge bearing 14 is installed on upper half shaft 15, lower half shaft 17, and the bearing hole sleeve of small frame 24 is on the bearing 14. Two loading hydraulic cylinders 3 and 5 are respectively connected to the small frame 24 through a ball joint, the loading hydraulic cylinder 3 is connected to the frame 2 through a ball joint, and the loading hydraulic cylinder 5 is connected to the H-shaped frame 1 through a ball joint. Four short shafts 12, 13, 19, 20 are fixedly connected on the H-shaped frame 1, and a wheel 18, 21, 25, 26 with a V-shaped groove is respectively arranged on each short shaft, and the V-shaped groove of each wheel is Contact with the circular arc △-shaped guide rail fixed on the frame 2, and support the H-shaped frame 1 on the frame 2, the center distance of the wheels 25, 26 can be adjusted; the center distance of the wheels 18, 21 can also be adjusted, through a wheel The clearance between 18, 21, 25, 26 and the circular arc △-shaped guide rail fixed on the frame 2 is adjusted so that the H-shaped frame 1 can reciprocate along the circular arc-shaped track of the frame 2, but there will be no gap between the two relatively shaken. The first guide rod 4 and the second guide rod 6 are also fixedly connected to the small frame 24, and the first guide rod 4 and the second guide rod 6 are respectively installed with two guide holes on the H-shaped frame 1 in a clearance fit manner. Together, the H frame 1 and the small frame 24 can move relative to each other, but cannot rotate relative to each other. The H-shaped frame 1 is connected to the connecting rod 8 through a hinge, and the connecting rod 8 is connected to the slide block 9 with a nut through a hinge. The output shaft is fixedly connected with the leading screw 10.

To scientifically and accurately evaluate the fatigue life of the rotor axial hinge bearing, it is first necessary to ensure that the working conditions, motion, load, lubrication and other conditions of the rotor horizontal hinge bearing fatigue test are consistent with the actual situation of the bearing during work. During the flight of the helicopter, it is necessary to manipulate the control mechanism to make the rotor tilt forward, backward, left, and right relative to the helicopter fuselage, so that the rotor can tilt forward, backward, left, and right. Horizontal force component, so that the helicopter flies forward, backward, left and right. Since the rotor is a beam with very low stiffness and great length, coupled with the change of wind speed, the rotor must be in the waving plane (rotor symmetry center line and rotor drive shaft When the rotor vibrates once in the waving plane, the rotor horizontal hinge bearing swings back and forth once, that is, the rotor horizontal hinge bearing frequently performs high-frequency small-angle reciprocating swings during the flight of the helicopter. The force situation of the rotor horizontal hinge bearing is: 1. to bear the centrifugal force of the rotor at different speeds; 2. the pulling force generated by the damper.

In the present invention, the servo motor 11 makes the rotor horizontal hinge bearing 4 produce high-frequency reciprocating swing through the lead screw 10, the connecting rod 8, the H-shaped frame 1, the guide rods 4, 6, and the frequency, amplitude, speed, and acceleration of the swing The real parameters of the rotor horizontal hinge bearing can be simulated through the control of the servo motor. The pulling force applied by the loading hydraulic cylinder 5 to the rotor horizontal hinge bearing 4 can accurately simulate the centrifugal pulling force generated by the high-speed rotation of the rotor through the control of the hydraulic system. The installation position and the pulling force size of the loading hydraulic cylinder 3 are just identical with the corresponding parameters of the damper installed on the rotor.

Claims (4)

1. A helicopter rotor horizontal hinge bearing fatigue testing machine, comprising a loading hydraulic cylinder (3, 5), an upper half shaft (15), a lower half shaft (17), a short shaft (12, 13, 19, 20) and wheels (18, 21, 25, 26), it is characterized in that: an outer arc △-shaped guide rail (22) and an inner arc △-shaped guide rail (23) are fixedly connected on the arc-shaped frame of the support frame (2) , the supporting frame (2) is also fixedly connected with the frame minor axis (16), on the frame minor axis (16) is fixedly connected with the upper half shaft (15) and the lower half shaft (17), on the upper half shaft (15) Helicopter rotor horizontal hinge bearing (14) is installed on the lower half shaft (17), and the bearing holes of the small frame (24) are sleeved on the bearing (14); the small frame (24) is respectively connected to two loading hydraulic cylinders by a ball hinge (3, 5), the loading hydraulic cylinder (3) is connected to the frame (2) through a ball joint, and the loading hydraulic cylinder (5) is connected to the H-shaped frame (1) through a ball joint. 2. The helicopter rotor horizontal hinge bearing fatigue testing machine according to claim 1 is characterized in that: four short shafts (12,13,19,20) are fixedly connected on the H-shaped frame (1), and on each short shaft Each has a wheel (18,21,25,26) with a V-shaped groove, and the V-shaped groove of each wheel is in contact with the circular arc △-shaped guide rail fixedly connected on the circular arc-shaped frame of the support frame (2), And the H-shaped frame (1) is supported on the frame (2), and the H-shaped frame (1) can reciprocate along the circular arc track of the frame (2). 3. The helicopter rotor horizontal hinge bearing fatigue testing machine according to claim 1 or 2, is characterized in that: the first guide rod (4) and the second guide rod (6) are also fixedly connected on the small frame (24) , the first guide rod (4) and the second guide rod (6) cooperate with two guide holes on the H-shaped frame (1) respectively. 4. The helicopter rotor horizontal hinge bearing fatigue testing machine according to claim 3 is characterized in that: the H-shaped frame (1) is connected by a hinge between the connecting rod (8), and the connecting rod (8) is connected with a nut by a hinge. The slide block (9) is connected, the slide block (9) with nut is matched with the leading screw (10), and the output shaft of the servo motor (11) is fixedly connected with the leading screw (10).

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