A test bench and method for testing the strength of a helicopter rotor automatic tilt support

Abstract

The application belongs to the technical field of helicopter strength test, and discloses a helicopter rotor automatic tilting device support strength test bench and method, a bottom loading frame is placed on the ground, the bottom loading frame comprises four stand columns and a bottom ring frame and a middle ring frame; an upper loading frame is fixed at the top of the four stand columns of the bottom loading frame, a middle loading frame is fixed on the middle ring frame; a fixed installation platform is fixedly installed on the middle loading frame; a to-be-tested automatic tilting device is vertically installed in the middle of the fixed installation platform; an axial loading device is fixed at one end on the ground and connected to a short lever of the automatic tilting device at the other end for axial loading; a lateral loading device is fixed at one end on the ground and connected to an extension shaft of the automatic tilting device at the other end for lateral loading; a torque loading device is fixed at one end on the ground and connected to a flange ear of the automatic tilting device at the other end for torque loading.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of helicopter strength test, and particularly relates to a helicopter rotor automatic tilting device support piece strength test bench and method. BACKGROUND

[0002] For support piece strength test, each direction load meeting flight state is applied to the support piece to check the fatigue life of the support piece. The main purpose is to verify the strength performance and weak position of the support piece and connecting parts, and to provide a basis for determining the service life.

[0003] For traditional similar test, gantry, column and other equipment are usually used to realize load application. This method has great limitations in layout and load point number. Especially for the application of tensile and compressive loads, the fixing device becomes extremely complicated, and the installation and adjustment are time-consuming and laborious. Meanwhile, the load application angle is difficult to control and guarantee, which is not conducive to the improvement of test loading precision. In addition, in the process of strength test of the bench built by the traditional method, most of the gantries, columns and other facilities are fixed by ground friction force. Therefore, during the fatigue test, these components are prone to looseness. In addition to re-tightening, the load application angle of each component also needs to be adjusted, which greatly affects the test efficiency and human resources. SUMMARY

[0004] The application discloses a helicopter rotor automatic tilting device support piece strength test bench and method, which can complete tensile and compressive load application of 8 directions in a small field area, and complete support piece assembly strength test.

[0005] The application solves the following technical problems: 1. matching test piece installation interface; 2. completing 8 direction load application; 3. each load meeting tensile and compressive requirements; 4. facilitating installation, easy to replace, saving installation time, shortening test period, improving test site neatness and improving loading precision.

[0006] Technical scheme:

[0007] A helicopter rotor automatic tilting device support piece assembly strength test bench, comprising: an upper loading frame, a middle loading frame, a bottom loading frame, an axial loading device, a lateral loading device, a torque loading device and an installation platform.

[0008] The bottom loading frame is placed on the ground, and the bottom loading frame comprises four columns and a bottom ring frame and a middle ring frame.

[0009] The upper loading frame is fixed on the top of the four vertical columns of the bottom loading frame, and the middle loading frame is fixed on the middle frame.

[0010] The automatic inclinometer is vertically installed in the middle of the fixed installation platform.

[0011] One end of the axial loading device is fixed on the ground, and the other end is connected to the short lever of the automatic inclinometer through the fixed installation platform for axial loading.

[0012] One end of the lateral loading device is fixed on the ground, and the other end is connected to the extension shaft of the automatic inclinometer for lateral loading.

[0013] One end of the torque loading device is fixed on the ground, and the other end is connected to the flange ear of the automatic inclinometer for torque loading.

[0014] Further, the upper loading frame is a square frame structure, which provides loading fulcrums for the lateral loading device and the torque loading device.

[0015] Further, the middle loading frame includes two parallel I-beams, and the two I-beams are fixed on the middle frame of the bottom loading frame.

[0016] Further, the axial loading device includes an axial fixed joint, an axial load actuator, an axial sensor, an axial length adjustment device, and an axial loading joint.

[0017] The axial fixed joint is fixed on the ground, the tail of the axial load actuator is fixed on the axial fixed joint, the piston rod of the axial load actuator is connected to the sensor and then connected to one end of the axial length adjustment device, the other end of the axial length adjustment device is connected to the axial loading joint, and the front end of the axial loading joint is connected to the short lever through a joint bearing.

[0018] Further, the test bench includes N sets of axial loading devices, N is the number of short levers of the automatic inclinometer, and the N sets of axial loading devices are arranged directly below the N short levers.

[0019] Further, the lateral loading device includes a lateral fixed joint, a lateral load actuator, a lateral vertical length adjustment device, a lateral steering fixed joint, a lateral steering device, a lateral horizontal length adjustment device, a lateral loading sensor, and a lateral loading adapter.

[0020] The lateral fixed joint is fixed on the ground, and the tail of the lateral load actuator is fixed on the lateral fixed joint. The piston rod of the lateral load actuator is connected to one end of the lateral vertical length adjustment device.

[0021] The lateral turning device is a right triangle, and the right angle vertex of the lateral turning device is fixed to the upper loading frame through a lateral turning fixed joint. The other end of the lateral vertical length adjusting device is fixedly connected with a non-right angle vertex of the lateral turning device. One end of the lateral horizontal length adjusting device is connected to the other non-right angle vertex of the lateral turning device. The other end of the lateral horizontal length adjusting device is connected to the lateral loading sensor, and then connected to a lateral loading adapter. The lateral loading adapter is connected to the extension shaft of the automatic tilting device.

[0022] Further, the test bench comprises two sets of lateral loading devices, and further comprises a lateral loading adapter;

[0023] The lateral loading adapter is a half-ring adapter with an ear, which is locked on the extension shaft of the automatic tilting device through a bolt;

[0024] The lateral loading adapters of the two sets of lateral loading devices are fixed at 90° on the lateral loading adapter.

[0025] Further, the torque loading device comprises an adjusting base, a torque fixed joint, a torque actuator, a torque vertical length adjusting device, a torque turning fixed joint, a torque turning device, a torque horizontal length adjusting device, a torque loading sensor and a torque loading adapter;

[0026] The adjusting base is fixed on the ground, and the tail of the torque actuator is connected to the adjusting base through the torque fixed joint. The piston rod of the torque actuator is connected to one end of the torque vertical length adjusting device.

[0027] The torque turning device is a right triangle, and the right angle vertex of the torque turning device is fixed to the upper loading frame through a torque turning fixed joint. The other end of the torque vertical length adjusting device is fixedly connected with a non-right angle vertex of the torque turning device. One end of the torque horizontal length adjusting device is connected to the other non-right angle vertex of the torque turning device. The other end of the torque horizontal length adjusting device is connected to the torque loading sensor, and then connected to a torque loading adapter,

[0028] The torque loading adapter is connected to the flange ear of the automatic tilting device, and the axis of the torque loading adapter is at an angle a with the axis of the automatic tilting device.

[0029] Further, the test bench comprises two sets of torque loading devices, and the two sets of torque loading devices are symmetrically arranged at 180°.

[0030] A helicopter rotor automatic tilting device support assembly strength test method, the method is implemented by the test bench, and the method comprises:

[0031] Step 1: Fix the automatic tilting device on the test bench;

[0032] Step two: connect the axial loading device, lateral loading device, torque loading device with the automatic tilting device;

[0033] Step three: set the actuation amplitude, frequency and phase of the axial load actuators, lateral load actuators and torque actuators in the axial loading device, lateral loading device and torque loading device;

[0034] The actuation amplitude and frequency of the N axial load actuators in the N sets of axial loading devices are A1 and F1 respectively, and the phases of the N axial load actuators differ by 360° / N from each other;

[0035] The actuation amplitude and frequency of the two sets of lateral load actuators are A2 and F1 respectively, and the phases of the two sets of lateral load actuators differ by 180°;

[0036] The actuation amplitude and frequency of the two sets of torque actuators are A3 and F1 respectively, and the phases of the two sets of lateral load actuators differ by 180°;

[0037] Step four: draw the load command curve and feedback curve of the axial, lateral and torque through the axial sensor, lateral loading sensor and torque loading sensor;

[0038] Step five: adjust the frequency F1 according to the difference between the load command curve and the feedback curve; when the difference between the load command curve and the feedback curve exceeds 20%, reduce the frequency F1, when it does not exceed 3%, increase the frequency F1, and keep the frequency F1 unchanged during 3%~20%;

[0039] Step six: after the frequency is adjusted to the appropriate range, the strength test of the automatic tilting device is carried out, and the fatigue life is measured.

[0040] The beneficial technical effects of the present application are:

[0041] The present application can perform strength test on similar guide cylinder structure test pieces, and can simultaneously apply tensile and compressive load to the load in 8 directions of the test piece 8.

[0042] All fixed positions are in the same rack, and the improvement of load application precision has a significant effect.

[0043] The test adopts an internal force rack form, and is designed according to the upper, middle and lower layers, compared with the traditional strength test site, the present application can improve the overall planning and layout of the test site installation, reduce the test site occupation, improve the installation efficiency and overall appearance of the test site, and the detection in the test process is also very convenient. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 It is a schematic diagram of a helicopter rotor automatic tilting device support assembly strength test rack structure;

[0045] Figure 2 Figure 1 is a schematic diagram of an upper loading frame 1 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0046] Figure 3 Figure 2 is a schematic diagram of a middle loading frame 2 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0047] Figure 4 Figure 3 is a schematic diagram of a bottom loading frame 3 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0048] Figure 5 Figure 4 is a schematic diagram of an axial loading device 4 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0049] Figure 6 Figure 5 is a schematic diagram of a lateral loading device 5 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0050] Figure 7 Figure 6 is a schematic diagram of a torque loading device 6 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0051] Figure 8 Figure 7 is a schematic diagram of a mounting platform 7 of a helicopter rotor automatic tilting device support assembly strength test bench;

[0052] Figure 9 Figure 8 is a schematic diagram of torque application of a helicopter rotor automatic tilting device support assembly strength test bench. DETAILED DESCRIPTION

[0053] A helicopter rotor automatic tilting device support assembly strength test bench, as shown in Figures 1-9 Figure 8, comprises an upper loading frame 1, a middle loading frame 2, a bottom loading frame 3, an axial loading device 4, a lateral loading device 5, a torque loading device 6, and a mounting platform 7. The upper loading frame 1 is arranged with mounting interfaces of the lateral loading device 5 and the torque loading device 6, is used for load steering fixation in the lateral loading device 5, and is arranged at the bottom with a mounting fixation interface of the bottom loading frame 3. The middle loading frame 2 is composed of two similar beam structures, is arranged with a mounting interface of the mounting platform 7, and is fixed in cooperation with a related interface of the bottom loading frame 3. The bottom loading frame 3 serves to support the entire test bench, is arranged with mounting fixation interfaces of the axial loading device 4, the lateral loading device 5, and the torque loading device 6, and forms an internal force system with the entire test bench.

[0054] The upper loading frame 1 is a square structure, is mainly used for steering device fixation of axial load and torque load, and is part of a load transmission structure of an internal force system

[0055] The middle loading frame 2 is mainly composed of two same beam structures, and is fixed at corresponding positions of the bottom loading frame 3, and mainly provides a fixing point for the installation platform 7 and ensures the position requirement of the installation platform

[0056] The bottom loading frame 3 is the main force bearing component in the whole rack system, and has corresponding installation fixed interfaces with the middle loading frame 2, the bottom loading frame 3, the axial loading device 4, the lateral loading device 5 and the torque loading device 6, so that the whole frame is integrated and forms an internal force rack system.

[0057] The axial loading device 4 mainly applies axial load, and there are four sets of the axial loading device 4 in the rack, which mainly include an axial fixed joint 4-1, an axial load actuator 4-2, an axial sensor 4-3, an axial length adjusting device 4-4, and an axial loading joint 4-5. The axial loading joint 4-5 is provided with a joint bearing, which is used to prevent load deviation caused by position deviation. The fixed end of the axial load actuator 4-2 is hinged and installed on the axial fixed joint 4-1; the axial load actuator 4-2, the axial sensor 4-3 and the axial length adjusting device 4-4 are connected with each other through threads.

[0058] The lateral loading device 5 mainly applies lateral load, and there are two sets of the lateral loading device 5 in the rack, which mainly include a lateral fixed joint 5-1, a lateral load actuator 5-2, a lateral vertical length adjusting device 5-3, a lateral steering fixed joint 5-4, a lateral steering device 5-5, a lateral horizontal length adjusting device 5-6, a lateral loading sensor 5-7, a lateral loading adapter 5-8 and a lateral loading joint 5-9. Bearings are inlaid in the two ear hole of the lateral steering fixed joint 5-4, which is used to reduce the friction force when the steering device turns, and joint bearings are inlaid in the ear hole of the lateral steering device 5-5, which is used to prevent load deviation caused by position deviation.

[0059] The torque loading device 6 mainly applies torque load, and there are two sets of the torque loading device 6 in the rack, which mainly include an adjusting base 6-1, a torque fixed joint 6-2, a torque actuator 6-3, a torque vertical length adjusting device 6-4, a torque steering fixed joint 6-5, a torque steering device 6-6, a torque horizontal length adjusting device 6-7, a torque loading sensor 6-8 and a torque loading joint 6-9. Bearings are inlaid in the two ear hole of the torque steering fixed joint 6-5, which is used to reduce the friction force when the steering device turns, and joint bearings are inlaid in the ear hole of the torque steering device 6-6, which is used to prevent load deviation caused by position deviation.

[0060] All the length adjusting devices are positive and negative threaded screw structures or threaded sleeve screw structures or other structures.

[0061] As Figure 1 A helicopter rotor automatic tilting device support assembly strength test bench, comprising: an upper loading frame 1, a middle loading frame 2, a bottom loading frame 3, an axial loading device 4, a lateral loading device 5, a torque loading device 6, and a mounting platform 7. The upper loading frame 1 is arranged with a mounting interface of the lateral loading device 5 and the torque loading device 6, is used for load steering fixation in the lateral loading device 5, and is arranged at the bottom with a mounting and fixation interface of the bottom loading frame 3. The middle loading frame 2 is composed of two similar beam structures, is arranged with a mounting interface of the mounting platform 7, and is fixed in cooperation with a related interface of the bottom loading frame 3. The bottom loading frame 3 serves to support the entire bench, is arranged with mounting and fixation interfaces of the axial loading device 4, the lateral loading device 5, and the torque loading device 6, so that the entire bench constitutes an internal force system

[0062] First, the middle loading frame 2 is fixed on the bottom loading frame 3 at corresponding positions, and then the test piece is mounted on the middle loading frame 2. Next, the axial loading device 4 is fixed with the bottom loading frame 3, the length of the axial length adjustment device 4-4 is adjusted to be connected with the test piece, the upper loading frame 1 is mounted on the bottom loading frame 3 at corresponding positions, the lateral loading joint 5-9 is mounted on the test piece at corresponding positions, and then the lateral loading device 5 and the torque loading device 6 are mounted.

[0063] Test method: after the installation of the bench and the test piece is completed, the length of each length adjustment device is adjusted to ensure the direction of the load application. Then the bench test can be debugged. During the debugging, the single-point debugging of each direction load actuator is performed first to verify the completeness of the actuator function and parameters. After the single-point debugging is completed, the actuator joint debugging of 30% load is performed. By judging the error of the load command and the feedback curve in each direction, the control parameters are adjusted to ensure that the load in each direction and the phase error are not greater than 3%. After the 30% load joint debugging is completed, the 100% load formal test can be started. During the test process, it is checked periodically whether each fastener is loose and the overall operation of the bench is observed.

Claims

1. A test bench for testing the strength of a support of a helicopter rotor automatic pitch control, characterized in that, The test bench comprises an upper loading frame, a middle loading frame, a bottom loading frame, an axial loading device, a lateral loading device, a torque loading device and a mounting platform. The bottom loading frame is placed on the ground, and comprises four vertical columns and a bottom ring frame and a middle ring frame. The upper loading frame is fixed at the top of the four vertical columns of the bottom loading frame, and the middle loading frame is fixed on the middle ring frame. The mounting platform is fixed on the middle loading frame. The upper loading frame is a square frame structure, and is used for providing loading fulcrums for the lateral loading device and the torque loading device. The axial loading device is fixed at one end on the ground, and is connected at the other end to the short lever of the automatic tilting device through the mounting platform for axial loading. The lateral loading device is fixed at one end on the ground, and is connected at the other end to the extension shaft of the automatic tilting device for lateral loading. The torque loading device is fixed at one end on the ground, and is connected at the other end to the flange ear of the automatic tilting device for torque loading. The lateral loading device comprises a lateral fixed joint, a lateral load actuator, a lateral vertical length adjusting device, a lateral turning fixed joint, a lateral turning device, a lateral horizontal length adjusting device, a lateral loading sensor and a lateral loading adapter. The lateral fixed joint is fixed on the ground, and the tail of the lateral load actuator is fixed on the lateral fixed joint. The lateral turning device is in the shape of a right-angled triangle, and the right-angled vertex of the lateral turning device is fixed on the upper loading frame through the lateral turning fixed joint.

2. The test bed of claim 1, wherein: The other end of the lateral vertical length adjusting device is fixedly connected to one non-right-angled vertex of the lateral turning device.

3. The test bed of claim 1, wherein: The other end of the lateral horizontal length adjusting device is connected to the other non-right-angled vertex of the lateral turning device. The other end of the lateral horizontal length adjusting device is connected to the lateral loading sensor, and then connected to the lateral loading adapter.

4. The test bed of claim 3, wherein: The lateral loading adapter is connected to the extension shaft of the automatic tilting device.

5. The test bed of claim 1, wherein: The middle loading frame comprises two parallel I-beams. The axial loading device comprises an axial fixed joint, an axial load actuator, an axial sensor, an axial length adjusting device and an axial loading adapter. The axial fixed joint is fixed on the ground, and the tail of the axial load actuator is fixed on the axial fixed joint. The piston rod of the axial load actuator is connected to the sensor, and then connected to one end of the axial length adjusting device. The other end of the axial length adjusting device is connected to the axial loading adapter. The other end of the axial loading adapter is connected to the short lever through a joint bearing. The test bench comprises N sets of axial loading devices, wherein N is the number of short levers of the automatic tilting device. The test bench comprises two sets of lateral loading devices, and further comprises a lateral loading adapter. The lateral loading adapter is a half-ring adapter with ears, and is locked on the extension shaft of the automatic tilting device through bolts. The lateral loading adapters of the two sets of lateral loading devices are fixed at 90° on the lateral loading adapter.

6. The test bed of claim 2, wherein: The torque loading device comprises an adjusting base, a torque fixing joint, a torque actuator, a torque vertical length adjusting device, a torque steering fixing joint, a torque steering device, a torque horizontal length adjusting device, a torque loading sensor and a torque loading joint. The adjusting base is fixed on the ground, the tail of the torque actuator is connected to the adjusting base through the torque fixing joint, and the piston rod of the torque actuator is connected to one end of the torque vertical length adjusting device. The torque steering device is in the shape of a right triangle, the right-angled vertex of the torque steering device is fixed to the upper loading frame through the torque steering fixing joint, the other non-right-angled vertex of the torque steering device is connected to the other end of the torque vertical length adjusting device, one end of the torque horizontal length adjusting device is connected to the other non-right-angled vertex of the torque steering device, and the other end of the torque horizontal length adjusting device is connected to the torque loading sensor and then to the torque loading joint. The torque loading joint is connected to the flange lug of the automatic tilting device, and the axis of the torque loading joint forms an angle a with the axis of the automatic tilting device.

7. The test bed of claim 6, wherein: The test bench comprises two sets of torque loading devices, and the two sets of torque loading devices are arranged in 180° symmetry.

8. A method for testing the strength of a support of a helicopter rotor automatic tilt, said method being carried out by means of a test bench according to any one of claims 1-7, characterized in that: The method comprises: Step one: fixing the automatic tilting device on the test bench; Step two: connecting the axial loading device, the lateral loading device and the torque loading device to the automatic tilting device; Step three: setting the actuation amplitude, frequency and phase of the axial load actuators, the lateral load actuators and the torque actuators in the axial loading device, the lateral loading device and the torque loading device; The actuation amplitudes and frequencies of the N axial load actuators in the N sets of axial loading devices are A1 and F1 respectively, and the phases of the N axial load actuators are different by 360° / N from each other; The actuation amplitudes and frequencies of the two sets of lateral load actuators are A2 and F1 respectively, and the phases of the two sets of lateral load actuators are different by 180°; The actuation amplitudes and frequencies of the two sets of torque actuators are A3 and F1 respectively, and the phases of the two sets of lateral load actuators are different by 180°; Step four: drawing the load command curve and the feedback curve of the axial force, the lateral force and the torque through the axial sensor, the lateral loading sensor and the torque loading sensor; Step five: adjusting the frequency F1 according to the difference between the load command curve and the feedback curve; when the difference between the load command curve and the feedback curve exceeds 20%, the frequency F1 is reduced, when the difference is less than 3%, the frequency F1 is increased, and when the difference is between 3% and 20%, the frequency F1 is kept unchanged; Step six: after the frequency is adjusted to the appropriate range, the strength test of the automatic tilting device is carried out, and the fatigue life thereof is measured.

Images