Full hinge support composite material loading device and method

Abstract

The invention provides a full-hinged composite material loading device, and the device comprises a first hinged structure which is connected with one end of a composite material test piece; the second twisted support structure is connected with the other end of the composite material test piece, and the first twisted support structure and the second twisted support structure form a full twisted support structure; meanwhile, the invention further provides a loading method of the full-hinged support composite material. The device is easy to install and high in bearing capacity, the problem of test interruption caused by spring piece breakage is solved, and the test efficiency is greatly improved.

Description

Technical Field

[0001] This application belongs to the technical field of fatigue testing, and particularly relates to a fully hinged composite material loading device and method. Background Art

[0002] In the fatigue test of a helicopter rotor system, the fatigue test of the main blade airfoil section is essential. Currently, the fatigue test of the main blade airfoil section usually adopts an excitation method. To better match the resonance frequency of the entire system, a non-hinged system composed of two horizontal spring plates and two vertical spring plates is set at the fixed end of the main blade airfoil section. So as to keep a stable vibration state near the resonance point of the entire test system.

[0003] During the vibration process, the spring plates often break. A fully hinged composite material loading device and method involved in the present invention abandons the non-hinged system composed of spring plates, avoiding the test interruption caused by the breakage of spring plates and affecting the test progress. Summary of the Invention

[0004] Object of the Invention: To provide a fully hinged composite material loading device and method, which solves the test interruption caused by the breakage of spring plates and greatly improves the test efficiency.

[0005] In a first aspect, the present application provides a fully hinged composite material loading device, and the device includes:

[0006] A first hinged structure, connected to one end of a composite material test piece;

[0007] A second hinged structure, connected to the other end of the composite material test piece, and the first hinged structure and the second hinged structure form a fully hinged structure.

[0008] Preferably, the device further includes a test bench; the first hinged structure includes:

[0009] A first test piece clamping assembly, one end of the first test piece clamping assembly is connected to one end of the composite material test piece; wherein, when the bolt of the first test piece clamping assembly is loosened, the composite material test piece can rotate axially;

[0010] A bending bearing joint, one end of the bending bearing joint is connected to the test bench, and the other end of the bending bearing joint is connected to the other end of the first test piece clamping assembly;

[0011] Preferably, the first hinged structure further includes:

[0012] A first pin shaft, one end of the first test piece clamping assembly is connected to one end of the composite material test piece through the first pin shaft;

[0013] The third pin shaft, the other end of the bending bearing joint is connected to the other end of the first test piece clamping assembly through the third pin shaft.

[0014] Preferably, the first hinge support structure further includes:

[0015] A sliding pair is arranged in the middle of the first test piece clamping assembly. The sliding pair is used to limit the lateral movement of the first test piece clamping assembly, ensuring the application of the lateral bending moment of the composite material test piece.

[0016] Preferably, the second hinge support structure includes:

[0017] A second test piece clamping assembly, one end of the second test piece clamping assembly is connected to the other end of the composite material test piece; wherein, when the bolts of the second test piece clamping assembly are loosened, the composite material test piece can rotate axially;

[0018] An excitation loading system, one end of the excitation loading system is connected to the other end of the second test piece clamping assembly, and the other end of the excitation loading system is connected to the test bench.

[0019] Preferably, the second hinge support structure further includes:

[0020] A second pin shaft, one end of the second test piece clamping assembly is connected to the other end of the composite material test piece through the second pin shaft;

[0021] A fourth pin shaft, one end of the excitation loading system is connected to the other end of the second test piece clamping assembly through the fourth pin shaft.

[0022] Preferably, loosening or tightening the bolts of the first test piece clamping assembly and the second test piece clamping assembly can rotatably change and lock the loading angle of the composite material test piece, thereby changing the direction of the bending moment applied to the monitoring area, and further ensuring that the bending moment loaded on the monitoring area of the composite material test piece meets the requirements.

[0023] Preferably, the excitation loading system is an eccentric wheel loading system.

[0024] In a second aspect, the present application also provides a fully hinge-supported composite material loading method, the method includes:

[0025] Step 1: One end of the composite material test piece is clamped by the first test piece clamping assembly through the first pin shaft, and the other end of the composite material test piece is clamped by the second test piece clamping assembly through the second pin shaft; loosen the tightening bolts of the first test piece clamping assembly and the first test piece clamping assembly, and the composite material test piece can rotate freely to adjust the ratio between the flapping and pitching moments during loading. Tighten the tightening bolts of the first test piece clamping assembly and the first test piece clamping assembly, and the composite material test piece cannot rotate, keeping the loading angle unchanged to maintain the ratio between the flapping and pitching moments.

[0026] Step 2: The other end of the first test piece clamping assembly is connected to the bending bearing joint through the third pin shaft. The bending bearing joint is fixed on the test bench. The third pin shaft can transmit the torque load generated due to deformation during the load application process of the composite material test piece to the bending bearing joint and finally to the test bench.

[0027] Step 3: The other end of the first test piece clamping assembly is connected to the bending bearing joint through the third pin shaft, replacing the original spring leaf damping system, avoiding the interruption of the test caused by the fracture of the spring leaf and affecting the test progress.

[0028] Step 4: Sliding pairs are symmetrically arranged in the middle of the first test piece clamping assembly to balance the bending moment in the pitching direction of the composite material test piece during the excitation loading system loading.

[0029] Step 5: The other end of the first test piece clamping assembly is connected to the excitation loading system through the fourth pin shaft to transmit the force applied by the excitation loading system to the composite material test piece.

[0030] Step 6: The excitation loading system is used to apply an excitation load to the entire system. The excitation loading system can apply an excitation load with adjustable frequency, stable and reliable. When the load application frequency of the excitation loading system is close to the natural frequency of the entire system, the composite material test piece starts to vibrate and the bending moment is completed.

[0031] The present application has the following technical effects:

[0032] A fully hinged composite material loading device and method involved in the present invention are simple to install and have strong load-bearing capacity, solving the interruption of the test caused by the fracture of the spring leaf and greatly improving the test efficiency; one end of the composite material test piece in the device forms a hinged support structure through the first pin shaft, the first test piece clamping assembly, the third pin shaft, and the bending bearing joint, and the other end of the composite material test piece forms a hinged support structure through the second pin shaft, the second test piece clamping assembly, the fourth pin shaft, and the excitation loading system, thus forming a fully hinged support structure. Abandoning the non-hinged support system composed of spring leaves, it avoids the obstruction of the test progress caused by the interruption of the test caused by the fracture of the spring leaf. Description of the Drawings

[0033] Figure 1It is a schematic structural diagram of a fully hinged composite material loading device provided by an embodiment of the present application;

[0034] Figure 2 It is a schematic structural diagram of a fully hinged composite material loading device provided by another embodiment of the present application;

[0035] Wherein: 1 composite material test piece, 2 first pin shaft, 3 first test piece clamping assembly, 4 second pin shaft, 5 second test piece clamping assembly, 6 third pin shaft, 7 bending bearing joint, 8 test bench, 9 sliding pair, 10 fourth pin shaft, 11 excitation loading system. Specific embodiments

[0036] Please refer to Figure 1 , a fully hinged composite material loading device provided by the present application is used to implement bending moment loading on a composite material test piece.

[0037] One end of the composite material test piece 1 is connected to the first test piece clamping assembly 3 through the first pin shaft 2. By loosening the bolts of the first test piece clamping assembly 3, the composite material test piece 1 can rotate axially; the other end of the composite material test piece 1 is connected to the second test piece clamping assembly 5 through the second pin shaft 4. By loosening the bolts of the second test piece clamping assembly 5, the composite material test piece 1 can rotate axially to adjust the vibration direction of the composite material test piece 1 and change the bending moment direction applied to the composite material test piece 1. The other end of the first test piece clamping assembly 3 is connected to the bending bearing joint 7 through the third pin shaft 6, and the third pin shaft 6 and the bending bearing joint 7 form a hinged support structure; the other end of the bending bearing joint 7 is fixedly supported on the test bench 8. The test bench 8 serves as the main load-bearing structure, and there is a sliding pair 9 in the middle of the first test piece clamping assembly 3 to limit the lateral movement of the first test piece clamping assembly 3; the other end of the second test piece clamping assembly 5 is connected to the excitation loading system 11 through the fourth pin shaft 10. The excitation loading system 11 can be an eccentric wheel loading system or other loading systems. As the main force-applying device, the excitation loading system 11 is also fixed on the test bench 8 so that the test bench 8 finally bears the load.

[0038] Loosening or tightening the bolts of the first test piece clamping assembly 3 and the second test piece clamping assembly 5 can rotate and lock the loading angle of the composite material test piece 1, thereby changing the bending moment direction applied to the monitoring area, and further making the bending moment loaded on the monitoring area of the composite material test piece 1 meet the requirements.

[0039] It should be noted that:

[0040] 1. One end of the composite material test piece 1 in this device forms a hinge support structure through the first pin shaft 2, the first test piece clamping assembly 3, the third pin shaft 6, and the bending bearing joint 7. The other end of the composite material test piece 1 forms a hinge support structure through the second pin shaft 4, the second test piece clamping assembly 5, the fourth pin shaft 10, and the vibration excitation loading system 11, thus forming a full hinge support structure;

[0041] 2. A novel full hinge support composite material loading device involved in the present invention solves the test interruption caused by the fracture of the spring piece and greatly improves the test efficiency;

[0042] 3. There is a sliding pair 9 in the middle of the first test piece clamping assembly 3 to limit the lateral movement of the first test piece clamping assembly 3, ensuring the application of the lateral bending moment of the test piece.

[0043] Please refer to the appendix Figure 2 , one end of the composite material test piece 1 is connected to the first test piece clamping assembly 3 through the first pin shaft 2. Loosen the bolts of the first test piece clamping assembly 3, and the composite material test piece 1 can rotate axially; the other end of the composite material test piece 1 is connected to the second test piece clamping assembly 5 through the second pin shaft 4. Loosen the bolts of the second test piece clamping assembly 5, and the composite material test piece 1 can rotate axially to adjust the vibration direction of the composite material test piece 1 and change the bending moment direction applied to the composite material test piece 1. The other end of the first test piece clamping assembly 3 is connected to the bending bearing joint 7 through the third pin shaft 6. The third pin shaft 6 and the bending bearing joint 7 form a hinge support structure; the other end of the bending bearing joint 7 is fixedly supported on the test bench 8. The test bench 8 is used as the main load-bearing structure, and there is a sliding pair 9 in the middle of the first test piece clamping assembly 3 to limit the lateral movement of the first test piece clamping assembly 3; the other end of the second test piece clamping assembly 5 is connected to the vibration excitation loading system 11 through the fourth pin shaft 10. The vibration excitation loading system 11 can be an eccentric wheel loading system or other loading systems. As the main force-applying device, the vibration excitation loading system 11 is also fixed on the test bench 8 so that the test bench 8 finally bears the load.

[0044] Loosening or tightening the bolts of the first test piece clamping assembly 3 and the second test piece clamping assembly 5 can rotate and lock the loading angle of the composite material test piece 1, thereby changing the bending moment direction applied to the monitoring area, and further making the bending moment loaded in the monitoring area of the composite material test piece 1 meet the requirements.

[0045] A fully hinged composite material loading device and method involved in the present invention are simple to install and have strong load-bearing capacity, solving the problem of test interruption caused by the fracture of the spring piece and greatly improving the test efficiency; one end of the composite material test piece 1 in the device forms a hinged support structure through the first pin shaft 2, the first test piece clamping assembly 3, the third pin shaft 6, and the bending bearing joint 7, and the other end of the composite material test piece 1 forms a hinged support structure through the second pin shaft 4, the second test piece clamping assembly 5, the fourth pin shaft 10, and the vibration excitation loading system 11, thus forming a fully hinged support structure. The non-hinged support system composed of spring pieces is abandoned, avoiding the obstruction of the test progress caused by the test interruption caused by the fracture of the spring piece.

[0046] In other embodiments of the present application, the provided loading method includes the following steps:

[0047] Step 1,

[0048] The first test piece clamping assembly 3 clamps one end of the composite material test piece 1 through the first pin shaft 2, and the second test piece clamping assembly 5 clamps the other end of the composite material test piece 1 through the second pin shaft 4. Loosen the tightening bolts of the first test piece clamping assembly 2 and the first test piece clamping assembly 5, and the composite material test piece 1 can rotate freely to adjust the ratio between the flapping and pitching moments during loading. Tighten the tightening bolts of the first test piece clamping assembly 2 and the first test piece clamping assembly 5, and the composite material test piece 1 cannot rotate, keeping the loading angle unchanged to maintain the ratio between the flapping and pitching moments;

[0049] Step 2,

[0050] The other end of the first test piece clamping assembly 3 is connected to the bending bearing joint 7 through the third pin shaft 6, and the bending bearing joint 7 is fixed on the test bench 8. The third pin shaft 6 can transfer the torque load generated due to the deformation during the load application process of the composite material test piece 1 to the bending bearing joint 7 and finally to the test bench.

[0051] Step 3,

[0052] The other end of the first test piece clamping assembly 3 is connected to the bending bearing joint 7 through the third pin shaft 6, replacing the original spring piece damping system, avoiding the test interruption caused by the fracture of the spring piece and affecting the test progress.

[0053] Step 4,

[0054] Sliding pairs 9 are symmetrically arranged in the middle of the first test piece clamping assembly 3, which can balance the bending moment in the pitching direction of the composite material test piece 1 during the loading of the vibration excitation loading system 11.

[0055] Step 5,

[0056] The other end of the first test piece clamping assembly 5 is connected to the excitation loading system 11 via the fourth pin shaft 10 to transmit the force applied by the excitation loading system 11 to the composite material test piece 1.

[0057] Step 6,

[0058] The excitation loading system 11 is used to apply an excitation load to the entire system. The excitation loading system 11 can apply an excitation load with adjustable frequency, stable and reliable. When the load application frequency of the excitation loading system 11 is close to the natural frequency of the entire system, the composite material test piece 1 starts to vibrate and the bending moment is completely applied.

Claims

1. A fully hinged composite material loading device, characterized in that, The device includes: A first gimbal structure connected to one end of the composite material test piece; A second gimbal structure connected to the other end of the composite material test piece, and the first gimbal structure and the second gimbal structure form a full gimbal structure.

2. The device according to claim 1, wherein The device further includes a test bench; the first gimbal structure includes: A first test piece clamping assembly, one end of the first test piece clamping assembly is connected to one end of the composite material test piece; wherein, when the bolt of the first test piece clamping assembly is loosened, the composite material test piece can rotate axially; A bending bearing joint, one end of the bending bearing joint is connected to the test bench, and the other end of the bending bearing joint is connected to the other end of the first test piece clamping assembly.

3. The device according to claim 2, characterized in that, The first gimbal structure further includes: A first pin shaft, one end of the first test piece clamping assembly is connected to one end of the composite material test piece through the first pin shaft; A third pin shaft, the other end of the bending bearing joint is connected to the other end of the first test piece clamping assembly through the third pin shaft.

4. The device according to claim 3, characterized in that, The first gimbal structure further includes: A sliding pair arranged in the middle of the first test piece clamping assembly, and the sliding pair is used to limit the lateral movement of the first test piece clamping assembly, ensuring the application of the lateral bending moment of the composite material test piece.

5. The device according to claim 2, characterized in that, The second gimbal structure includes: A second test piece clamping assembly, one end of the second test piece clamping assembly is connected to the other end of the composite material test piece; wherein, when the bolt of the second test piece clamping assembly is loosened, the composite material test piece can rotate axially; An excitation loading system, one end of the excitation loading system is connected to the other end of the second test piece clamping assembly, and the other end of the excitation loading system is connected to the test bench.

6. The device according to claim 5, characterized in that, The second gimbal structure further includes: A second pin shaft, one end of the second test piece clamping assembly is connected to the other end of the composite material test piece through the second pin shaft; A fourth pin shaft, one end of the excitation loading system is connected to the other end of the second test piece clamping assembly through the fourth pin shaft.

7. The device according to claim 5, characterized in that, Loosening or tightening the bolts of the first test piece clamping assembly and the second test piece clamping assembly can rotate and lock the loading angle of the composite material test piece, thereby changing the direction of the bending moment applied to the monitoring area, and further making the bending moment loaded on the monitoring area of the composite material test piece meet the requirements.

8. The device according to claim 5, characterized in that, The excitation loading system is an eccentric wheel loading system.

9. A fully hinged composite material loading method, characterized in that, The method includes: Step 1: The first test piece clamping assembly clamps one end of the composite material test piece through the first pin shaft, and the second test piece clamping assembly clamps the other end of the composite material test piece through the second pin shaft; loosen the tightening bolts of the first test piece clamping assembly and the first test piece clamping assembly, and the composite material test piece can rotate freely to adjust the ratio between the flapping and pitching bending moments during loading. Tighten the tightening bolts of the first test piece clamping assembly and the first test piece clamping assembly, and the composite material test piece cannot rotate, keeping the loading angle unchanged to maintain the ratio between the flapping and pitching bending moments; Step 2: The other end of the first test piece clamping assembly is connected to the bending bearing joint through the third pin shaft. The bending bearing joint is fixed on the test bench. The third pin shaft can transfer the torque load generated by the deformation during the load application process of the composite material test piece to the bending bearing joint and finally to the test bench. Step 3: The other end of the first test piece clamping assembly is connected to the bending bearing joint through the third pin shaft, replacing the original spring plate damping system, avoiding the test interruption caused by the fracture of the spring plate and affecting the test progress. Step 4: The sliding pairs are symmetrically arranged in the middle of the first test piece clamping assembly, which can balance the bending moment in the swinging direction of the composite material test piece during the excitation loading system loading. Step 5: The other end of the first test piece clamping assembly is connected to the excitation loading system through the fourth pin shaft to transfer the force applied by the excitation loading system to the composite material test piece. Step 6: The excitation loading system is used to apply the excitation load to the whole system. The excitation loading system can apply an excitation load with adjustable frequency, stable and reliable. When the load application frequency of the excitation loading system is close to the natural frequency of the whole system, the composite material test piece begins to vibrate and the bending moment is completed.

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