Helicopter blade stiffness detection device and detection method

Abstract

This invention discloses a helicopter rotor blade stiffness testing device, including a testing platform, a flapping stiffness testing mechanism, and a torsional stiffness testing mechanism. The drive source I has a power output end I, which is connected to a limiting member I. The power output end I is driven to move forward or backward along the flapping direction of the helicopter rotor blade under test. A tension / compression testing element is used to detect tension / compression data between the limiting member I and the power output end I. A distance testing element is used to detect the distance data of the forward or backward movement of the power output end I. A rotor is used to limit the tip of the helicopter rotor blade under test. The drive source II has a power output end II, and the rotor is driven to rotate around a quarter chord of the helicopter rotor blade under test via the power output end II. A torque testing element is used to detect the torque data of the rotor's oscillation. An angle testing element is used to detect the angle data of the rotor's oscillation. This device can improve the accuracy of helicopter rotor blade stiffness testing.

Description

Technical Field

[0001] This invention relates to the field of helicopter rotor blade stiffness testing, and specifically to a helicopter rotor blade stiffness testing device and testing method. Background Technology

[0002] Current technology has poor accuracy in detecting the stiffness of helicopter rotor blades;

[0003] Errors in swing stiffness testing include the influence of the device's own mass on the measurement results, the influence of the self-weight or friction of the measuring mechanism on the measurement results, and errors in sensor installation, use, or adjustment, all of which have certain influencing factors.

[0004] Errors in torsional stiffness testing include the fact that the preset measuring point and the actual measuring point on the blade are not the same due to the presence of torsional load, and the measurement result of the measuring point position is an approximation, which affects the measurement result. In addition, the detection error of this measurement method also includes the measurement error accumulated by multiple sensors, resulting in low measurement accuracy of the entire detection device.

[0005] Therefore, to solve the above problems, a helicopter rotor blade stiffness testing device and testing method are needed to optimize the testing results of the above-mentioned flapping stiffness testing and torsional stiffness testing, reduce the influence of environmental, operational and testing factors on the measurement results, and improve the stiffness testing accuracy of helicopter rotor blades. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide a helicopter rotor blade stiffness detection device and detection method, which can optimize the detection results of the above-mentioned flapping stiffness detection and torsional stiffness detection, reduce the influence of environmental, operational and detection factors on the measurement results, and improve the stiffness detection accuracy of helicopter rotor blades.

[0007] The helicopter rotor blade stiffness testing device of the present invention includes a testing platform, a flapping stiffness testing mechanism, and a torsional stiffness testing mechanism;

[0008] The testing platform in this solution has a frame-like structure, which provides a flat working surface and is used for the installation of the swing stiffness testing mechanism and the torsional stiffness testing mechanism. The overall testing mechanism has a high degree of integration, high space utilization, and can control costs.

[0009] The flapping stiffness detection mechanism includes a blade root clamping block I, a limiting component I, a drive source I, a tension / compression detection element, and a distance detection element;

[0010] The blade root clamping block I is set on the testing table, and the blade root clamping block I is used to limit the root of the helicopter blade under test; the limiting member I is set on the testing table through ball bearings I, and the limiting member I is used to limit the tip of the helicopter blade under test; the setting of ball bearings I can reduce the friction between the testing table and the limiting member I, and in this solution there are several ball bearings I, so as to minimize the friction and reduce the influence of external environmental factors on the flapping stiffness test results;

[0011] The drive source I is set on the testing platform. The drive source I has a power output end I, which is connected to the limiting member I. The power output end I is driven to move forward or backward along the flapping direction of the helicopter blade under test. It has the advantages of better stability, stronger operability, and higher testing efficiency and accuracy.

[0012] The tension / compression detection element is used to detect the tension / compression data between the limiting member I and the power output end I; the distance detection element is used to detect the forward or backward distance data of the power output end I.

[0013] In this solution, the drive source I is a push rod of the prior art, preferably capable of pushing and pulling in a set direction, which will not be described in detail here; the tension and pressure detection element is any tension and pressure sensor of the prior art, preferably capable of obtaining tension and pressure data at a specified position, which will not be described in detail here; the distance detection element is any displacement sensor of the prior art, preferably capable of obtaining displacement data at a specified position, which will not be described in detail here.

[0014] More specifically, the housing of the push rod, which serves as the drive source I, is limited on the testing platform via a hinged seat. The housing of the push rod and the hinged seat are hinged together, and the hinge axis of the hinged push rod housing is parallel to the extension direction of the helicopter blade under test. A tension / compression sensor is installed between the power output end of the push rod and the limiting component I. The connection end of the tension / compression sensor to the push rod is fixed, and the connection end of the tension / compression sensor to the limiting component I is hinged. The hinge axis of the hinged tension / compression sensor to the limiting component I is parallel to the extension direction of the helicopter blade under test. The housing of the displacement sensor is fixed on the push rod housing. The front end of the displacement sensor telescopic rod is fixed to the power output end of the push rod, and the telescopic rod of the displacement sensor is parallel to the power output rod of the push rod, so that the detection end of the displacement sensor records data synchronously with the forward or backward movement of the power output end of the push rod. This reduces the influence of external factors on the measurement results and obtains more accurate detection parameters.

[0015] The torsional stiffness detection mechanism includes a blade root clamping block II, a limiting component II, a drive source II, a torque detection element, and an angle detection element.

[0016] The blade root clamping block II is set on the testing table, and the blade root clamping block II is used to limit the root of the helicopter blade to be tested; the limiting member II includes a stator and a rotor, the stator is set on the testing table, the rotor is set on the stator, and the rotor is used to limit the tip of the helicopter blade to be tested.

[0017] The drive source II is set on the testing platform. The drive source II has a power output end II, which is connected to the rotor drive. The rotor is driven by the power output end II to rotate around 1 / 4 chord of the helicopter blade under test. It has better stability, stronger operability, and higher testing efficiency and accuracy.

[0018] The torque detection element is used to detect the torque data of the rotor oscillation; the angle detection element is used to detect the angle data of the rotor oscillation.

[0019] In this solution, the drive source II is a drive motor of the prior art, preferably capable of outputting a set torque, which will not be elaborated here; the torque detection element is any torque sensor of the prior art, preferably capable of obtaining torque data at a specified position, which will not be elaborated here; the angle detection element is any angle sensor of the prior art, preferably capable of obtaining angle data at a specified position, which will not be elaborated here.

[0020] More specifically, the housing of the drive motor, which serves as the drive source II, is fixed on the test platform by a mounting bracket. The power output shaft of the drive motor is parallel to the extension direction of the rotor blade of the helicopter under test. This solution also includes a transmission assembly, which is used to input the power of the drive motor to the rotor. The transmission assembly includes a driving gear fixed coaxially with the power output shaft of the drive motor and a driven gear fixed with the same rotation center as the rotor. The driving gear and the driven gear are in transmission engagement, and the driven gear is driven to rotate by the driving gear.

[0021] The active gear is connected to the power output shaft of the drive motor via a connecting shaft. The connecting shaft with the active output gear and the power output shaft of the drive motor are combined into a whole by any coupling in the prior art. The active gear is also limited by a connecting shaft housing fixed to the stator. The connecting shaft with the active output gear is rotatably installed through the connecting shaft housing. The active gear and the power output shaft of the drive motor are respectively located on both sides of the connecting shaft housing, which further ensures the detection accuracy of torsional stiffness and reduces the influence of the rotational drop of the long shaft end and the rotational runout of the long shaft end.

[0022] The torque sensor is installed between the power output shaft of the drive motor and the connecting shaft on which the drive gear is assembled. The two ends of the torque sensor are respectively fixed on the power output shaft of the drive motor and the connecting shaft on which the drive gear is assembled.

[0023] An angle sensor is mounted on the testing platform via an auxiliary support. The detection end of the angle sensor is equipped with a functional gear, which engages with the driven gear. Driven by the driven gear, the functional gear causes the rotor's rotation angle to be collected by the angle sensor, thus reducing the influence of external factors on the measurement results and obtaining more accurate detection parameters.

[0024] The blade root clamping block I and blade root clamping block II, simulating helicopter rotor clamps, are respectively set on the testing platform. The root of the helicopter blade under test is limited in a detachable manner by two bolts arranged in parallel, which facilitates disassembly and assembly and has high structural strength, ensuring the accuracy of stiffness test results.

[0025] Furthermore, the torsional stiffness testing mechanism also includes an assembly stand, which is fixed on the testing platform. The stator limits the rotor by a ring, and ball bearings II are provided between the stator and the rotor. That is, the connection structure between the stator and the rotor in this solution is similar to that of a bearing. The stator is fixed on the assembly stand, and the rotor, which is driven to rotate, is installed inside the stator, and the two are coaxial, which can better define the rotation angle and rotation accuracy of the rotor. The housing of the drive motor is fixed on the assembly stand by a fixing seat, the angle sensor is fixed on the assembly stand by an auxiliary bracket, the connecting shaft housing is fixed on the assembly stand, and the driven gear is fixed on the rotor, with the rotation center of the driven gear coinciding with the rotation center of the rotor to ensure the accuracy of the test results. In this solution, the driven gear is an arc-shaped rack, which can limit the deflection angle of the rotor and prevent the helicopter blade under test from breaking due to overload. The assembly stand of this solution integrates the various parts of the torsional stiffness testing mechanism into a unified whole, which can improve the transmission accuracy and the test accuracy.

[0026] Furthermore, it also includes an auxiliary pad, which is driven to support the helicopter blade under test on the testing table or to release the support from the helicopter blade under test. The top of the auxiliary pad has a positioning groove, which is used to limit the yaw of the helicopter blade under test. The use of the auxiliary pad in this solution allows the helicopter blade under test to be supported by the testing table even in the unassembled testing state, which is more conducive to the installation of the helicopter blade under test on the testing mechanism. After the helicopter blade under test is assembled on the testing mechanism, the auxiliary pad no longer supports the helicopter blade under test, ensuring the testing accuracy of the required parameters of the helicopter blade under test.

[0027] Furthermore, the limiting member I has a limiting cavity I, the inner wall surface of the limiting cavity I is parallel to the blade surface of the helicopter blade under test, and after the helicopter blade under test is limited by the limiting member I, the inner wall surface of the limiting cavity I is in contact with the blade surface of the helicopter blade under test that is limited.

[0028] This design makes the limiting of the helicopter rotor blade under test more reliable and the test results more accurate. The limiting component I includes a driven sliding base and a limiting strip that can be detachably mounted on the sliding base. The sliding base is generally inverted "T" shape. Its horizontal plate serves as a base plate for mounting several ball bearings I to reduce friction, and its vertical plate serves as an assembly plate for mounting the limiting strip. The limiting strip and the assembly plate together form a limiting cavity I that can be controlled to open and close, which is conducive to limiting the helicopter rotor blade under test on the limiting component I. The power output end I of the drive source I is set on the back of the assembly plate, opposite to the limiting strip. A reinforcing rib is set on the side of the assembly plate where the power output end I is mounted, which connects the horizontal plate and the assembly plate, improving the reliability of the overall structure and ensuring the testing of the flapping stiffness of the helicopter rotor blade under test.

[0029] The rotor has a limiting cavity II, the inner wall surface of the limiting cavity II is parallel to the blade surface of the helicopter blade under test, and after the helicopter blade under test is limited by the rotor, the inner wall surface of the limiting cavity II is in contact with the blade surface of the helicopter blade under test that is limited.

[0030] This design makes the limiting of the helicopter rotor blade under test more reliable and the test results more accurate. The limiting seat is formed near the rotation center of the rotor. The rotor also includes a limiting cover plate that can be detachably assembled on the limiting seat. The limiting seat and the limiting cover plate together form a limiting cavity II that can be controlled to open and close. This helps to limit the helicopter rotor blade under test on the rotor. The limiting cavity II is close to the top surface of the test stand in the height direction, which improves the reliability of the overall structure and helps to ensure the testing of the torsional stiffness of the helicopter rotor blade under test.

[0031] Furthermore, after the rotor blade of the helicopter under test is limited by the limiting component I, the connection point between the power output end I and the limiting component I is close to the 1 / 4 chord line of the rotor blade in the height direction. The optimal alignment is achieved by overlap; during actual assembly and use, this overlap should be ensured as much as possible to further improve the accuracy of the flapping stiffness test results.

[0032] Furthermore, after the rotor limits the rotor blade under test, the rotation center of the rotor approximately coincides with the 1 / 4 chord line of the rotor blade. This approximately coincidence means that theoretically, the two remain aligned. The approximation includes the influence of manufacturing and assembly factors on the actual results, which will not be elaborated here, further improving the accuracy of the torsional stiffness test results.

[0033] Furthermore, a limiting part is connected to the stator, and a limiting end is provided on the rotor. The limiting end is controlled to engage or disengage with the limiting part so that the rotor is positioned at a designated position on the stator or released from the designated position on the stator.

[0034] In this solution, the limiting part is a functional hole formed on the assembly stand, and the limiting end is a support arm formed on the rotor. The support arm extends radially outward toward the rotor, and a mating hole is provided on the support arm. The mating hole can coincide with the functional hole. The torsional stiffness detection mechanism also includes a pin. The connection between the functional hole and the mating hole through the pin makes the rotor limited on the assembly stand. In this state, the rotor and stator form an integral whole and cannot be driven to rotate. This is used to more conveniently assemble the helicopter blade under test on the torsional stiffness detection mechanism. After the helicopter blade under test is assembled on the torsional stiffness detection mechanism, the pin is removed, so that the rotor can be driven to rotate relative to the stator. In this state, the torsional stiffness of the helicopter blade can be detected.

[0035] Furthermore, the stator is provided with angle limiting components, which are two components respectively located on the front and rear sides of the limiting end in the rotation direction;

[0036] The rotor is limited to rotate within a preset angle by the stroke limit of the limiting end by the two angle limiting members.

[0037] In this solution, the angle limiting component includes a fixed base and an adjusting rod. The fixed base is fixed on the assembly stand, and the adjusting rod is a bolt and nut design. The fixed base has a threaded hole for the bolt thread to pass through, so that the extension length of the screw on the fixed base can be adjusted to limit the rotation angle of the rotor. The angle limiting component consists of two parts, one on the front side and one on the rear side of the support arm in the rotation direction, which serve a protective function.

[0038] This solution also discloses a helicopter rotor blade stiffness detection method based on the aforementioned helicopter rotor blade stiffness detection device, including the following detection steps:

[0039] S1. The swing stiffness testing mechanism is run under no-load to obtain the tensile and compressive data of the limit component I within the preset stroke;

[0040] The torsional stiffness testing mechanism is run under no-load to obtain torque data I of the rotor at a preset angle;

[0041] S2. The rotor blade of the helicopter under test is assembled on the flapping stiffness detection mechanism. The flapping stiffness detection mechanism is started to obtain the tensile and compressive data of the limiting component I in the preset stroke II.

[0042] Alternatively, if the helicopter rotor blade under test is mounted on the torsional stiffness testing mechanism, the torsional stiffness testing mechanism is activated to obtain the rotor torque data II at a preset angle.

[0043] S3. Tension and Compression Data II - Tension and Compression Data I: Obtain the measured values ​​of tension and compression of the helicopter rotor blade under test;

[0044] Torque Data II - Torque Data I: Obtain the measured torque values ​​of the helicopter rotor blades under test.

[0045] In step S1, data can be uniformly obtained and sent to the computer for processing according to the actual situation. In actual operation, only step S2 needs to be performed. The obtained data can be directly uploaded to the computer to obtain the measured value. Then, the required data can be calculated using the measured value. This can greatly shorten the detection process, and the detection accuracy can be strictly controlled, resulting in a more accurate structure and higher reference value.

[0046] The beneficial effects of the present invention are as follows: The helicopter rotor blade stiffness testing device and testing method disclosed in the present invention, by setting up a flapping stiffness testing mechanism and a torsional stiffness testing mechanism, makes the testing integration and efficiency higher. Moreover, the flapping stiffness testing mechanism and torsional stiffness testing mechanism of the present invention provide more realistic and accurate testing data of the helicopter rotor blade under test, which greatly improves the finished product quality of the helicopter rotor blade under test. Attached Figure Description

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0048] Figure 1 This is a schematic diagram of the structure of the present invention;

[0049] Figure 2 This is a schematic diagram of the main structure of the present invention;

[0050] Figure 3 This is a top view of the structure of the present invention;

[0051] Figure 4 This is a side view of the structure of the present invention;

[0052] Figure 5 For the present invention Figure 3 A schematic diagram of the AA-direction structure. Detailed Implementation

[0053] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the main structure of the present invention; Figure 3 This is a top view of the structure of the present invention; Figure 4 This is a side view of the structure of the present invention; Figure 5 For the present invention Figure 3 The schematic diagram of the AA-direction structure is shown in the figure. The helicopter rotor blade stiffness detection device in this embodiment includes a detection platform 1, a flapping stiffness detection mechanism and a torsional stiffness detection mechanism.

[0054] The testing platform 1 in this solution has a frame-like structure, which is used to provide a flat working surface and to install the swing stiffness testing mechanism and the torsional stiffness testing mechanism. The overall testing mechanism has a high degree of integration, high space utilization, and can control costs.

[0055] The flapping stiffness detection mechanism includes a blade root clamping block I2, a limiting component I3, a drive source I4, a tension / compression detection element 5, and a distance detection element 6;

[0056] The blade root clamping block I2 is set on the testing table 1. The blade root clamping block I2 is used to limit the root of the helicopter blade to be tested. The limiting member I3 is set on the testing table 1 through the ball I7. The limiting member I3 is used to limit the tip of the helicopter blade to be tested. The setting of the ball I7 can reduce the friction between the testing table 1 and the limiting member I3. In this solution, there are several balls I7 to minimize the friction and reduce the influence of external environmental factors on the flapping stiffness test results.

[0057] The drive source I4 is set on the test platform 1. The drive source I4 has a power output end I. The power output end I is connected to the limiting member I3. The power output end I is driven to move forward or backward along the flapping direction of the helicopter blade under test. It has the advantages of better stability, stronger operability, and higher detection efficiency and detection accuracy.

[0058] The tension / compression detection element 5 is used to detect the tension / compression data between the limiting member I3 and the power output end I; the distance detection element 6 is used to detect the forward or backward distance data of the power output end I.

[0059] In this solution, the drive source I4 is a push rod of the prior art, preferably capable of pushing and pulling in a set direction, and will not be described in detail here; the tension and pressure detection element 5 is any tension and pressure sensor of the prior art, preferably capable of obtaining tension and pressure data at a specified position, and will not be described in detail here; the distance detection element 6 is any displacement sensor of the prior art, preferably capable of obtaining displacement data at a specified position, and will not be described in detail here.

[0060] More specifically, the housing of the push rod, which serves as the drive source I4, is limited on the testing table 1 by a hinged seat. The housing of the push rod and the hinged seat are hinged together, and the hinge axis of the hinged push rod housing is parallel to the extension direction of the helicopter blade under test. A tension / compression sensor is set between the power output end of the push rod and the limiting member I3. The connection end of the tension / compression sensor and the push rod is fixed, and the connection end of the tension / compression sensor and the limiting member I3 is hinged. The hinge axis of the hinged tension / compression sensor and the limiting member I3 is parallel to the extension direction of the helicopter blade under test. The housing of the displacement sensor is fixed on the push rod housing. The front end of the displacement sensor telescopic rod is fixed to the power output end of the push rod, and the telescopic rod of the displacement sensor is set parallel to the power output rod of the push rod, so that the detection end of the displacement sensor records data synchronously with the forward or backward movement of the power output end of the push rod. This reduces the influence of external factors on the measurement results and obtains more accurate detection parameters.

[0061] The torsional stiffness detection mechanism includes a blade root clamping block II8, a limiting component II, a drive source II9, a torque detection element 10, and an angle detection element 11.

[0062] The blade root clamping block II 8 is set on the testing table 1. The blade root clamping block II 8 is used to limit the root of the helicopter blade to be tested. The limiting member II includes a stator 12 and a rotor 13. The stator 12 is set on the testing table 1, and the rotor 13 is set on the stator 12. The rotor 13 is used to limit the tip of the helicopter blade to be tested.

[0063] The drive source II 9 is set on the test platform 1. The drive source II 9 has a power output end II. The power output end II is connected to the rotor 13. The rotor 13 is driven by the power output end II to rotate around 1 / 4 chord of the helicopter blade under test. It has the advantages of better stability, stronger operability, higher detection efficiency and detection accuracy.

[0064] The torque detection element 10 is used to detect the torque data of the rotor 13 swinging; the angle detection element 11 is used to detect the angle data of the rotor 13 swinging.

[0065] In this scheme, the drive source II9 is ​​a drive motor of the prior art, preferably capable of outputting a set torque, and will not be described in detail here; the torque detection element 10 is any torque sensor of the prior art, preferably capable of obtaining torque data at a specified position, and will not be described in detail here; the angle detection element 11 is any angle sensor of the prior art, preferably capable of obtaining angle data at a specified position, and will not be described in detail here.

[0066] More specifically, the housing of the drive motor, which serves as the drive source II9, is fixed on the test table 1 by a mounting bracket. The power output shaft of the drive motor is parallel to the extension direction of the rotor blade of the helicopter under test. This solution also includes a transmission assembly, which is used to input the power of the drive motor to the rotor 13. The transmission assembly includes a drive gear 14 that is coaxially fixed with the power output shaft of the drive motor and a driven gear 15 that is fixed with the same rotation center as the rotor 13. The drive gear 14 and the driven gear 15 are in transmission engagement, and the driven gear 15 is rotated by the drive gear 14.

[0067] The active gear 14 is connected to the power output shaft of the drive motor via a connecting shaft. The connecting shaft with the active output gear and the power output shaft of the drive motor are combined into a whole by any coupling in the prior art. The active gear 14 is also limited by a connecting shaft housing fixed to the stator 12. The connecting shaft with the active output gear is rotatably installed through the connecting shaft housing. The active gear 14 and the power output shaft of the drive motor are respectively located on both sides of the connecting shaft housing, which further ensures the detection accuracy of torsional stiffness and reduces the influence of the rotational drop of the long shaft end and the rotational runout of the long shaft end.

[0068] The torque sensor is set between the power output shaft of the drive motor and the connecting shaft on which the active gear 14 is mounted. The two ends of the torque sensor are respectively fixed on the power output shaft of the drive motor and the connecting shaft on which the active gear 14 is mounted.

[0069] An angle sensor is mounted on the testing platform 1 via an auxiliary bracket. The detection end of the angle sensor is equipped with a functional gear, which engages with the driven gear 15. Driven by the driven gear 15, the rotation angle of the rotor 13 is collected by the angle sensor, thereby reducing the influence of external factors on the measurement results and obtaining more accurate detection parameters.

[0070] The blade root clamping block I2 and blade root clamping block II8, simulating helicopter rotor clamps, are respectively set on the testing table 1. The root of the helicopter blade under test is limited in a detachable manner by two bolts arranged in parallel, which is conducive to disassembly and assembly and has high structural strength, ensuring the accuracy of stiffness test results.

[0071] In this embodiment, the torsional stiffness testing mechanism further includes an assembly frame 16, which is fixed on the testing table 1. The stator 12 limits the rotor 13 by a ring, and ball bearings II are provided between the stator 12 and the rotor 13. That is, the connection structure between the stator 12 and the rotor 13 in this solution is similar to that of a bearing. The stator 12 is fixed on the assembly frame 16, and the rotor 13 is driven to rotate and installed inside the stator 12. The two are coaxial, which can better define the rotation angle and rotation accuracy of the rotor 13. The housing of the drive motor is fixed on the assembly frame 16 by a fixing seat. The angle sensor is fixed on the assembly stand 16 via an auxiliary bracket. The connecting shaft housing is also fixed on the assembly stand 16. The driven gear 15 is fixed on the rotor 13, and the rotation center of the driven gear 15 coincides with the rotation center of the rotor 13 to ensure the accuracy of the test results. In this solution, the driven gear 15 is an arc-shaped rack, which can limit the deflection angle of the rotor 13 and prevent the helicopter blade under test from breaking due to overload. The assembly stand 16 of this solution integrates the various parts of the torsional stiffness testing mechanism into a unified whole, which can improve the transmission accuracy and the test accuracy.

[0072] In this embodiment, an auxiliary pad 17 is also included. The auxiliary pad 17 is driven to support the helicopter blade under test on the testing table 1 or to release the support of the helicopter blade under test. The top of the auxiliary pad 17 has a positioning groove, which is used to limit the yaw of the helicopter blade under test. The use of the auxiliary pad 17 in this solution allows the helicopter blade under test to be supported by the testing table 1 even when it is not assembled for testing, which is more conducive to the installation of the helicopter blade under test on the testing mechanism. After the helicopter blade under test is assembled on the testing mechanism, the auxiliary pad 17 no longer provides support for the helicopter blade under test, ensuring the detection accuracy of the required parameters of the helicopter blade under test.

[0073] In this embodiment, the limiting member I3 has a limiting cavity I, the inner wall surface of the limiting cavity I is parallel to the blade surface of the helicopter blade to be tested, and after the helicopter blade to be tested is limited by the limiting member I3, the inner wall surface of the limiting cavity I is in contact with the blade surface of the helicopter blade to be tested that is limited.

[0074] This design makes the limiting of the helicopter rotor blade under test more reliable and the test results more accurate. The limiting component I3 includes a driven sliding base and a limiting strip that can be detachably mounted on the sliding base. The sliding base is generally inverted "T" shape. Its horizontal plate serves as a base plate for mounting several ball bearings I7 to reduce friction, and its vertical plate serves as an assembly plate for mounting the limiting strip. The limiting strip and the assembly plate together form a limiting cavity I that can be controlled to open and close, which is conducive to limiting the helicopter rotor blade under test on the limiting component I3. The power output end I of the drive source I4 is set on the back of the assembly plate, opposite to the limiting strip. A reinforcing rib is set on the side of the assembly plate where the power output end I is mounted to connect the horizontal plate and the assembly plate, which improves the reliability of the overall structure and is conducive to ensuring the testing of the flapping stiffness of the helicopter rotor blade under test.

[0075] The rotor 13 has a limiting cavity II. The inner wall of the limiting cavity II is parallel to the blade surface of the helicopter blade under test. After the helicopter blade under test is limited by the rotor 13, the inner wall of the limiting cavity II is in contact with the blade surface of the helicopter blade under test that is limited.

[0076] This design makes the limiting of the helicopter blade under test more reliable and the test results more accurate. The rotor 13 forms a limiting seat near the rotation center. The rotor 13 also includes a limiting cover plate that can be detachably assembled on the limiting seat. The limiting seat and the limiting cover plate together form a limiting cavity II that can be controlled to open and close. This helps to limit the helicopter blade under test on the rotor 13. The limiting cavity II is close to the top surface of the test stand 1 in the height direction, which improves the reliability of the overall structure and helps to ensure the test of the torsional stiffness of the helicopter blade under test.

[0077] In this embodiment, after the helicopter rotor blade under test is limited by the limiting member I3, the connection point between the power output end I and the limiting member I is close to the 1 / 4 chord line of the helicopter rotor blade under test in the height direction. The optimal structure is to overlap, and the overlap should be ensured as much as possible during actual assembly and use to further improve the accuracy of the flapping stiffness test results.

[0078] In this embodiment, after the rotor 13 limits the rotor blade under test, the rotation center of the rotor approximately coincides with the 1 / 4 chord line of the rotor blade. This approximately coincidence means that theoretically the two remain aligned. The approximation includes the influence of manufacturing and assembly factors on the actual result, which will not be elaborated here, further improving the accuracy of the torsional stiffness detection results.

[0079] In this embodiment, a limiting part is connected to the stator 12, and a limiting end 18 is provided on the rotor 13. The limiting end 18 is controlled to engage or disengage with the limiting part so that the rotor 13 is positioned at a specified position on the stator 12 or released from the specified position on the stator 12.

[0080] In this design, the limiting part is a functional hole formed on the assembly stand 16, and the limiting end 18 is a support arm formed on the rotor 13. The support arm extends radially outward toward the rotor 13, and a mating hole is provided on the support arm. The mating hole can coincide with the functional hole. The torsional stiffness detection mechanism also includes a pin 19. The connection between the functional hole and the mating hole is achieved by the pin 19, so that the rotor 13 is limited on the assembly stand 16. In this state, the rotor 13 and the stator 12 form an integral unit and cannot be driven to rotate. This is used to more conveniently assemble the helicopter blade under test on the torsional stiffness detection mechanism. After the helicopter blade under test is assembled on the torsional stiffness detection mechanism, the pin 19 is removed, so that the rotor 13 can be driven to rotate relative to the stator 12. In this state, the torsional stiffness of the helicopter blade can be detected.

[0081] In this embodiment, the stator 12 is provided with an angle limiting member 20, and the angle limiting member 20 consists of two members respectively provided on the front and rear sides of the limiting end 18 in the rotation direction.

[0082] The rotor 13 is limited to rotate within a preset angle by the stroke limit of the limiting end 18 by the two angle limiting members 20.

[0083] In this solution, the angle limiting component 20 includes a fixed base and an adjusting rod. The fixed base is fixed on the assembly stand 16. The adjusting rod is designed with a bolt and nut. The fixed base has a threaded hole for the bolt thread to pass through, so that the extension length of the screw can be adjusted on the fixed base to limit the rotation angle of the rotor 13. The angle limiting component 20 consists of two parts, one on the front side and one on the rear side of the support arm in the rotation direction, which serve a protective function.

[0084] This solution also discloses a helicopter rotor blade stiffness detection method based on the aforementioned helicopter rotor blade stiffness detection device, including the following detection steps:

[0085] S1. The swing stiffness testing mechanism is run under no-load to obtain the tensile and compressive data of the limit component I3 within the preset stroke;

[0086] The torsional stiffness testing mechanism is run under no-load to obtain torque data I of rotor 13 at a preset angle;

[0087] S2. The rotor blade of the helicopter under test is assembled on the flapping stiffness detection mechanism. The flapping stiffness detection mechanism is started to obtain the tension and compression data II of the limit component I3 in the preset stroke; more specifically, the drive source I4, tension and compression detection element 5 and distance detection element 6 are started to obtain the corresponding data.

[0088] Alternatively, if the helicopter rotor blade under test is mounted on the torsional stiffness testing mechanism, the torsional stiffness testing mechanism is activated to obtain torque data II of rotor 13 at a preset angle; more specifically, the drive source II9, torque detection element 10 and angle detection element 11 are activated to obtain the corresponding data.

[0089] S3. Tension and Compression Data II - Tension and Compression Data I: Obtain the measured values ​​of tension and compression of the helicopter rotor blade under test;

[0090] Torque Data II - Torque Data I: Obtain the measured torque values ​​of the helicopter rotor blades under test.

[0091] In step S1, data can be uniformly obtained and sent to the computer for processing according to the actual situation. In actual operation, only step S2 needs to be performed. The obtained data can be directly uploaded to the computer to obtain the measured value. Then, the required data can be calculated using the measured value. This can greatly shorten the detection process, and the detection accuracy can be strictly controlled, resulting in a more accurate structure and higher reference value.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A helicopter rotor blade stiffness testing device, characterized in that: This includes a testing platform, a swing stiffness testing mechanism, and a torsional stiffness testing mechanism; The flapping stiffness detection mechanism includes a blade root clamping block I, a limiting component I, a drive source I, a tension / compression detection element, and a distance detection element; The blade root clamping block I is set on the testing platform, and the blade root clamping block I is used to limit the root of the helicopter blade to be tested; The limiting component I is set on the testing table by ball I, and the limiting component I is used to limit the tip of the helicopter rotor blade to be tested; The drive source I is set on the test platform. The drive source I has a power output end I. The power output end I is connected to the limiting member I. The power output end I is driven to move forward or backward along the flapping direction of the rotor blade of the helicopter under test. The tension / compression detection element is used to detect the tension / compression data between the limiting member I and the power output end I; the distance detection element is used to detect the forward or backward distance data of the power output end I. The torsional stiffness detection mechanism includes a blade root clamping block II, a limiting component II, a drive source II, a torque detection element, and an angle detection element. The blade root clamping block II is set on the testing table, and the blade root clamping block II is used to limit the root of the helicopter blade to be tested; the limiting member II includes a stator and a rotor, the stator is set on the testing table, the rotor is set on the stator, and the rotor is used to limit the tip of the helicopter blade to be tested. The torque detection element is used to detect the torque data of the rotor swing; the angle detection element is used to detect the angle data of the rotor swing. The limiting member I has a limiting cavity I, the inner wall surface of the limiting cavity I is parallel to the blade surface of the helicopter blade under test, and after the helicopter blade under test is limited by the limiting member I, the inner wall surface of the limiting cavity I is in contact with the blade surface of the helicopter blade under test that is limited. The rotor has a limiting cavity II, the inner wall surface of the limiting cavity II is parallel to the blade surface of the helicopter blade under test, and after the helicopter blade under test is limited by the rotor, the inner wall surface of the limiting cavity II is in contact with the blade surface of the helicopter blade under test that is limited. The stator limits the rotor by means of a ring, and ball bearings II are provided between the stator and the rotor.

2. The helicopter rotor blade stiffness testing device according to claim 1, characterized in that: It also includes an auxiliary pad, which is driven to support the helicopter blade under test on the test table or to release the support of the helicopter blade under test.

3. The helicopter rotor blade stiffness testing device according to claim 1, characterized in that: After the rotor blade of the helicopter under test is limited by the limiting component I, the connection point between the power output end I and the limiting component I is close to the 1 / 4 chord line of the rotor blade of the helicopter under test in the height direction.

4. The helicopter rotor blade stiffness testing device according to claim 1, characterized in that: After the rotor limits the rotor blade of the helicopter under test, the rotation center of the rotor is approximately coincident with the 1 / 4 chord of the rotor blade of the helicopter under test.

5. The helicopter rotor blade stiffness testing device according to claim 1, characterized in that: The stator is connected to a limiting part, and the rotor is provided with a limiting end, which is controlled to engage or disengage with the limiting part.

6. The helicopter rotor blade stiffness testing device according to claim 5, characterized in that: The stator is provided with angle limiting components, and the angle limiting components are two respectively provided on the front side and the rear side of the limiting end in the rotation direction; The rotor is limited to rotate within a preset angle by the stroke limit of the limiting end by the two angle limiting members.

7. A method for detecting helicopter rotor blade stiffness based on the helicopter rotor blade stiffness detection device according to any one of claims 1-6, characterized in that: The following testing steps are included: S1. The swing stiffness testing mechanism is run under no-load to obtain the tensile and compressive data of the limit component I within the preset stroke; The torsional stiffness testing mechanism is run under no-load to obtain torque data I of the rotor at a preset angle; S2. The rotor blade of the helicopter under test is assembled on the flapping stiffness detection mechanism. The flapping stiffness detection mechanism is started to obtain the tensile and compressive data of the limiting component I in the preset stroke II. Alternatively, if the helicopter rotor blade under test is mounted on the torsional stiffness testing mechanism, the torsional stiffness testing mechanism is activated to obtain the rotor torque data II at a preset angle. S3. Tension and Compression Data II - Tension and Compression Data I: Obtain the measured values ​​of tension and compression of the helicopter rotor blade under test; Torque Data II - Torque Data I: Obtain the measured torque values ​​of the helicopter rotor blades under test.

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