Propeller blade centrifugal and flapping load coordinated loading device

Abstract

The invention relates to the technical field of fatigue test devices, in particular to a propeller blade centrifugal and waving load coordinated loading device which comprises a to-be-loaded blade, a centrifugal loading assembly and a waving loading assembly, and the centrifugal loading assembly and the waving loading assembly apply corresponding loads to the same loading point of the to-be-loaded blade through a switching assembly. According to the invention, through the cooperative arrangement of the second centrifugal transfer fork lug and the pin shaft in the transfer assembly, the loading points of the centrifugal load and the flapping bending moment load can be arranged at the same pin shaft point position, and the loading points are endowed with sufficient degree of freedom, so that the applied centrifugal load can smoothly and correspondingly steer; meanwhile, the centrifugal loading assembly and the loading point are adjustably connected through the adjusting mechanism provided with the threads in the forward and reverse rotation directions in cooperation with the steel wire rope, and installation and operation are convenient.

Description

Technical Field

[0001] This application relates to the field of fatigue testing equipment technology, and in particular to a propeller blade centrifugal and flapping load coordination loading device. Background Technology

[0002] During use, engineering structures are subjected to alternating loads, which can lead to fatigue failure. To ensure their safety, their fatigue performance needs to be tested. For example, propeller blades, as one of the most critical components of an aircraft, are subjected to complex cyclic alternating loads under long-term high-speed rotation, making them prone to accumulated fatigue damage, which can then lead to deformation, cracks, or even fracture. The performance of propeller blades directly affects the overall performance of the aircraft and is related to flight safety. Currently, the effective method to solve this problem is through fatigue testing to obtain the fatigue performance of the propeller blades.

[0003] Fatigue tests on propeller blades are generally conducted in three parts: inner, middle, and outer. The flapping moment is applied by the actuator in a position-controlled manner, while the centrifugal force is applied by the centrifugal actuator in a force-controlled manner. During installation, it is necessary to ensure that the chord of the test profile is horizontal.

[0004] During the experiment, the root of the propeller blade is a fixed end. The flight stress is simulated by applying loads to the blade body. However, in existing test devices, the centrifugal load applied along the blade axis during loading often has a significant unloading effect on the flapping load due to the way it is applied. Even after the blade undergoes bending moment deformation, the centrifugal load is still applied along the original axis, constantly applying a horizontal straightening force to the blade, which hinders the bending moment deformation. It is difficult to apply the corresponding centrifugal load in a timely manner according to the blade deformation, and it also seriously affects the actual distribution of the flapping bending moment load on the blade body, which does not match the flight state and cannot accurately assess the fatigue performance of the blade. Therefore, it is necessary to design a propeller blade centrifugal and flapping coordinated loading device to realistically simulate the loads under flight conditions and obtain reliable and accurate test data. Summary of the Invention

[0005] This application provides a propeller blade centrifugal and flapping load coordination loading device to solve the problem that the centrifugal load applied in the prior art easily causes unloading of the flapping load, affecting the actual flapping bending moment load distribution on the blade, which is inconsistent with the flight state and cannot accurately assess the fatigue performance of the blade.

[0006] This application provides a propeller blade centrifugal and flapping load coordination loading device, including:

[0007] The blade to be loaded is installed on the blade fatigue test bench, and its root is fixedly connected to the fatigue test bench through a connecting device.

[0008] A centrifugal loading component is arranged along the axis of the blade to be loaded, and is used to apply a centrifugal load to the blade to be loaded.

[0009] A waving loading component is arranged perpendicular to the axis of the blade to be loaded, and is used to apply a waving bending moment load to the blade to be loaded;

[0010] The centrifugal loading component and the waving loading component apply the corresponding loads to the same loading point of the blade to be loaded via a transition component.

[0011] Preferably, the adapter component includes:

[0012] A loading fixture is clamped at the end of the blade to be loaded that is furthest from its root.

[0013] The second centrifugal adapter fork is fixedly connected to the loading fixture by a bolt assembly;

[0014] The pin is inserted into the end of the second centrifugal adapter fork that is away from the loading fixture.

[0015] Preferably, the centrifugal loading assembly includes a centrifugal actuator, which transmits the centrifugal load to the loading point via a steel wire rope, a centrifugal pulley, and an adjusting mechanism connected in sequence.

[0016] Preferably, the wire rope is wound around the outer surface of the centrifugal pulley, one end of the adjusting mechanism is rotatably connected to the centrifugal pulley through the first centrifugal adapter fork, and the other end of the adjusting mechanism is rotatably connected to the adapter assembly through the pin.

[0017] Preferably, the waving loading component includes a waving actuator and a waving adapter fork, the waving adapter fork being disposed at the output end of the waving actuator, and one end of the waving adapter fork being rotatably connected to the adapter component via the pin.

[0018] Preferably, the adjustment mechanism includes:

[0019] A threaded adapter sleeve, wherein two sections of internal threaded grooves with opposite directions of rotation are respectively opened at both ends of the threaded adapter sleeve;

[0020] A positive threaded tie rod, one end of which is threadedly connected to the inside of the threaded adapter cylinder, and the other end is provided with the first centrifugal adapter fork lug;

[0021] A reverse threaded tie rod, one end of which is threadedly connected to the other end of the threaded adapter cylinder, and the other end is rotatably connected to the adapter assembly via the pin.

[0022] Preferably, the reverse threaded tie rod, the waving adapter fork, and the second centrifugal adapter fork are all provided with through holes for inserting the pin, and the reverse threaded tie rod, the waving adapter fork, and the second centrifugal adapter fork are coaxially hinged through the pin.

[0023] Preferably, the rotating end of the anti-threaded tie rod is nested inside the waving adapter fork, and the rotating end of the waving adapter fork is nested inside the second centrifugal adapter fork.

[0024] Preferably, the loading fixture includes:

[0025] Upper and lower fixed clamps;

[0026] The blade fixing block is sandwiched between the upper and lower fixing plates and has a fixing cavity that matches the shape of the blade to be loaded. One end of the blade to be loaded is engaged with the inside of the blade fixing block.

[0027] Preferably, the centrifugal loading assembly further includes a force sensor located between the centrifugal actuator and the wire rope.

[0028] The beneficial effects of this application are as follows:

[0029] The propeller blade centrifugal and flapping load coordination loading device of this application, through the cooperation between the second centrifugal adapter fork and the pin in the adapter assembly, allows the loading points of the centrifugal load and the flapping moment load to be set at the same pin point, and gives the loading point sufficient degrees of freedom, so that the applied centrifugal load can smoothly change direction accordingly, reducing the influence of the centrifugal load on the blade bending moment distribution. At the same time, the adjustable connection between the centrifugal loading assembly and the loading point is achieved by the adjustment mechanism with positive and negative spiral threads and the steel wire rope, which facilitates installation and operation. During the test, the centrifugal load is applied first, and then the flapping load is applied. Combined with the degree of freedom design of each adapter fork and the pin in the adapter assembly, the load distribution of the blade is ensured to truly simulate the flight state, and finally more accurate and reliable fatigue test data is obtained. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 A schematic diagram of the overall structure of the propeller blade centrifugal and flapping load coordination loading device provided in the embodiments of this application;

[0032] Figure 2 This is a schematic diagram of the structure of the adapter component provided in the embodiments of this application;

[0033] Figure 3 This is a schematic diagram of the structure of the centrifugal loading component provided in the embodiments of this application;

[0034] Figure 4 This is a schematic diagram of the structure of the waving loading component provided in an embodiment of this application;

[0035] Figure 5 This is a schematic diagram of the structure of the adjustment mechanism provided in the embodiments of this application;

[0036] Figure 6 This is a schematic diagram of a blade test specimen under load provided in an embodiment of this application;

[0037] Figure 7 This is a schematic diagram of the overall installation of the propeller blade centrifugal and flapping load coordination loading device provided in the embodiments of this application.

[0038] Figure label:

[0039] 1. Blade to be loaded; 2. Connecting device; 3. Centrifugal loading assembly; 31. Centrifugal actuator cylinder; 32. Steel wire rope; 33. Centrifugal pulley; 34. First centrifugal adapter fork; 35. Force sensor; 4. Swinging loading assembly; 41. Swinging actuator cylinder; 42. Swinging adapter fork; 5. Adapter assembly; 51. Loading fixture; 52. Second centrifugal adapter fork; 53. Pin; 54. Upper and lower fixing plates; 55. Blade fixing block; 6. Adjustment mechanism; 61. Threaded adapter cylinder; 62. Positive threaded tie rod; 63. Negative threaded tie rod. Detailed Implementation

[0040] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] The following is combined Figures 1-7 This application describes the propeller blade centrifugal and flapping load coordination loading device provided in the embodiments of this application.

[0042] Reference Figure 1As shown in the embodiment of this application, the propeller blade centrifugal and flapping load coordination loading device includes a blade 1 to be loaded mounted on a blade fatigue test bench, a centrifugal loading component 3 arranged along the axial direction of the blade 1 to be loaded for applying centrifugal load to the blade 1 to be loaded, and a flapping loading component 4 arranged perpendicular to the axial direction of the blade 1 to be loaded for applying flapping bending moment load to the blade 1 to be loaded. The root of the blade 1 to be loaded is fixedly connected to the fatigue test bench through a connecting device 2. The centrifugal loading component 3 and the flapping loading component 4 apply corresponding loads to the same loading point of the blade 1 to be loaded through a transition component 5.

[0043] By cooperating with the second centrifugal adapter fork 52 in the adapter assembly 5 and the pin 53, the loading points of the centrifugal load and the flapping moment load can be set at the same pin 53 position, giving the loading point sufficient degrees of freedom. This allows the applied centrifugal load to smoothly change direction, reducing the impact of the centrifugal load on the blade bending moment distribution. At the same time, the adjustable connection between the centrifugal loading assembly 3 and the loading point is achieved through the adjustment mechanism 6 with forward and reverse spiral threads and the wire rope 32, facilitating installation and operation. During the test, the centrifugal load is applied first, followed by the flapping load. The design of the degrees of freedom of each adapter fork and the pin 53 in the adapter assembly 5 ensures that the load distribution on the blade truly simulates the flight state, ultimately obtaining more accurate and reliable fatigue test data.

[0044] Please continue reading. Figure 2 ,like Figure 2 As shown, it is a structural schematic diagram of the adapter component 5 provided in the embodiment of this application;

[0045] In some specific embodiments, the adapter component 5 includes:

[0046] Loading fixture 51 is clamped at the end of the blade 1 to be loaded that is away from its root.

[0047] The second centrifugal adapter fork 52 is fixedly connected to the loading fixture 51 by a bolt group;

[0048] The pin 53 is inserted into the end of the second centrifugal adapter fork 52 away from the loading fixture 51.

[0049] Please continue reading. Figure 3 ,like Figure 3 As shown, it is a schematic diagram of the structure of the centrifugal loading component 3 provided in the embodiment of this application;

[0050] In some specific embodiments, the centrifugal loading assembly 3 includes a centrifugal actuation cylinder 31, which transmits the centrifugal load to the loading point through a steel wire rope 32, a centrifugal pulley 33 and an adjustment mechanism 6 connected in sequence.

[0051] In some specific embodiments, the wire rope 32 is wound around the outer surface of the centrifugal pulley 33, one end of the adjusting mechanism 6 is rotatably connected to the centrifugal pulley 33 through the first centrifugal adapter fork 34, and the other end of the adjusting mechanism 6 is rotatably connected to the adapter assembly 5 through the pin 53.

[0052] Please continue reading. Figure 4 ,like Figure 4 As shown, it is a structural schematic diagram of the waving loading component 4 provided in the embodiment of this application;

[0053] In some specific embodiments, the waving loading component 4 includes a waving actuator 41 and a waving adapter fork 42. The waving adapter fork 42 is disposed at the output end of the waving actuator 41. The output end of the waving actuator 41 is rotatably connected to the adapter component 5 through the waving adapter fork 42. The waving actuator 41 applies a waving bending moment load to the loading point through the waving adapter fork 42 to simulate the lift force in the propeller flight state.

[0054] Please continue reading. Figure 5 ,like Figure 5 As shown, it is a structural schematic diagram of the adjustment mechanism 6 provided in the embodiment of this application;

[0055] In some specific embodiments, the adjustment mechanism 6 includes:

[0056] The threaded adapter sleeve 61 has two internal threaded grooves with opposite directions of rotation at both ends.

[0057] A positive threaded tie rod 62 has one end threadedly connected to the inside of the threaded adapter cylinder 61, and the other end is provided with the first centrifugal adapter fork lug 34.

[0058] The reverse threaded tie rod 63 has one end threadedly connected to the other end of the threaded adapter cylinder 61, and the other end rotatably connected to the adapter assembly 5 via a pin 53.

[0059] Specifically, the threaded adapter cylinder 61 is a cylindrical structure with a through hole inside. Both ends of the cylindrical structure have screw threads for threaded connection, and the threads at both ends of the threaded adapter cylinder 61 have opposite directions of rotation. The outer surfaces of one end of the positive threaded pull rod 62 and the negative threaded pull rod 63 are respectively provided with positive and negative screw threads for threaded connection with the threaded adapter cylinder 61. The positive and negative threaded pull rods are respectively screwed to the corresponding ends of the threaded adapter cylinder 61, so that the operator can rotate the threaded adapter cylinder 61 to simultaneously drive the positive and negative threaded pull rods at both ends to move in opposite directions or away from each other, or adjust the relative distance between them by rotating the positive and negative threaded pull rods at either end. This can amplify the stroke of the centrifugal actuator cylinder 31, so that the steel wire rope 32 does not need to be straightened during installation. It can be straightened and adjusted later in the installation process, reducing the installation difficulty and improving the operational flexibility.

[0060] In some specific embodiments, the reverse threaded pull rod 63, the waving adapter fork 42, and the second centrifugal adapter fork 52 are all provided with through holes for inserting the pin 53. The reverse threaded pull rod 63, the waving adapter fork 42, and the second centrifugal adapter fork 52 are coaxially hinged through the pin 53. The first centrifugal adapter fork 34, the second centrifugal adapter fork 52, and the waving adapter fork 42 are all concave blocks with a rotating groove at one end, and the through hole is opened at the rotating groove end of the concave block.

[0061] In some specific embodiments, the rotating end of the anti-threaded tie rod 63 is nested inside the flapping transition fork 42, and the rotating end of the flapping transition fork 42 is nested inside the second centrifugal transition fork 52. The rotating ends of the flapping transition fork 42 and the second centrifugal transition fork 52 are the ends with rotating grooves, and the rotating end of the anti-threaded tie rod 63 is the end away from the threaded transition cylinder 61. The two transition forks and the anti-threaded tie rod 63 are hinged together coaxially and in a layered nesting manner by a common pin 53, so that the centrifugal load and flapping bending moment load applied by the centrifugal actuator cylinder 31 and the flapping actuator cylinder 41 are concentrated at the same pin 53 located in the transition assembly 5. The corresponding loads are concentrated at the same loading point and then applied to the test end of the blade 1 to be loaded via the loading fixture 51 in the transition assembly 5.

[0062] Please continue reading. Figure 6 ,like Figure 6 As shown, it is a schematic diagram of the blade test specimen under load provided in the embodiment of this application;

[0063] During the loading process, a centrifugal load is first applied. The centrifugal actuator 31 transmits the centrifugal load to the blade test piece 1, which is to be loaded, through the wire rope 32, centrifugal pulley 33, adjustment mechanism 6, first centrifugal transfer fork 34 and pin 53. Then, a flapping moment load is applied. The flapping actuator 41 applies a flapping moment to the blade test piece through the flapping transfer fork 42 to simulate the lift force on the blade in flight.

[0064] Before the flapping moment load is applied, the anti-threaded tie rod 63 is rotatably connected to the adapter assembly 5 via the pin 53. The applied centrifugal load is applied along the axial direction of the blade test piece itself. When the flapping moment load is applied, the blade of the blade test piece 1, which is the blade to be loaded, deforms under stress, and its axial direction changes. The loading direction of the centrifugal load applied to its test end should also change accordingly. At this time, due to the degree of freedom at the pin 53, the centrifugal load can be smoothly transferred to F. 离心 The direction is applied along F at the loading point. 离心 The centrifugal load in the direction of F, instead of the centrifugal load in the horizontal straight line in the traditional mode, at this time, along F 离心 The centrifugal load applied in the direction can generate along F 离心1 and F 离心2 The component of the force along the direction of F, and among them... 离心2 The component of the force in the direction can be obtained from along F 挥舞 The components of the waving moment load applied at the same loading point in the same direction are canceled out, reducing the influence of the centrifugal component on the blade bending moment distribution, leaving the required F along the blade's own axis. 离心1 The component of the force in the direction of the blade axis ensures that the applied centrifugal load only acts in the direction of the blade axis, providing a more reliable and accurate simulation of the bending moment distribution on the blade during flight, and making the test data more precise and reliable.

[0065] In some specific embodiments, the loading fixture 51 includes:

[0066] Upper and lower fixed clamps 54;

[0067] The blade fixing block 55 is sandwiched between the upper and lower fixing plates 54 and has a fixing cavity that matches the shape of the blade 1 to be loaded. One end of the blade 1 to be loaded is engaged inside the blade fixing block 55.

[0068] The upper and lower fixing plates 54 are fixed to the blade fixing block 55 by bolts or screws. The upper and lower fixing plates 54 and the blade fixing block 55 are provided with threaded holes for inserting bolts or screws at corresponding positions. On the other hand, the blade fixing block can also be a cured product of glass fiber or glue, etc., which fills the fixing cavity between the blade and the upper and lower fixing plates 54, to strengthen the connection between the blade and the upper and lower fixing plates 54.

[0069] Please continue reading. Figure 7 ,like Figure 7 As shown, it is an overall installation schematic diagram of the propeller blade centrifugal and flapping load coordination loading device provided in the embodiment of this application;

[0070] In some specific embodiments, the centrifugal loading assembly 3 further includes a force sensor 35 located between the centrifugal actuation cylinder 31 and the wire rope 32, for monitoring the magnitude of the centrifugal load transmitted to the loading point.

[0071] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0072] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0073] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0074] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0075] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A propeller blade centrifugal and flapping load coordinating loading device, characterized in that, include: The blade to be loaded is installed on the fatigue test bench, and its root is fixedly connected to the fatigue test bench through a connecting device. A centrifugal loading component is arranged along the axis of the blade to be loaded, and is used to apply a centrifugal load to the blade to be loaded. A waving loading component is arranged perpendicular to the axis of the blade to be loaded, and is used to apply a waving bending moment load to the blade to be loaded; The centrifugal loading component and the waving loading component apply the corresponding loads to the same loading point of the blade to be loaded via a transition component.

2. The propeller blade centrifugal and flapping load coordinating loading device according to claim 1, characterized in that, The adapter component includes: A loading fixture is clamped at the end of the blade to be loaded that is furthest from its root. The second centrifugal adapter fork is fixedly connected to the loading fixture by a bolt assembly; The pin is inserted into the end of the second centrifugal adapter fork that is away from the loading fixture.

3. The propeller blade centrifugal and flapping load coordinating loading device according to claim 2, characterized in that, The centrifugal loading assembly includes a centrifugal actuator cylinder, which transmits the centrifugal load to the loading point via a steel wire rope, a centrifugal pulley, and an adjustment mechanism connected in sequence.

4. The propeller blade centrifugal and flapping load coordinating loading device according to claim 3, characterized in that, The steel wire rope is wound around the outer surface of the centrifugal pulley. One end of the adjustment mechanism is rotatably connected to the centrifugal pulley through the first centrifugal adapter fork, and the other end of the adjustment mechanism is rotatably connected to the adapter assembly through the pin.

5. The propeller blade centrifugal and flapping load coordinating loading device according to claim 4, characterized in that, The waving loading component includes a waving actuator and a waving adapter fork. The waving adapter fork is located at the output end of the waving actuator, and one end of the waving adapter fork is rotatably connected to the adapter component via the pin.

6. The propeller blade centrifugal and flapping load coordination loading device according to claim 5, characterized in that, The adjustment mechanism includes: A threaded adapter sleeve, wherein two sections of internal threaded grooves with opposite directions of rotation are respectively opened at both ends of the threaded adapter sleeve; A positive threaded tie rod, one end of which is threadedly connected to the inside of the threaded adapter cylinder, and the other end is provided with the first centrifugal adapter fork lug; A reverse threaded tie rod, one end of which is threadedly connected to the other end of the threaded adapter cylinder, and the other end is rotatably connected to the adapter assembly via the pin.

7. The propeller blade centrifugal and flapping load coordinating loading device according to claim 6, characterized in that, The reverse threaded tie rod, the waving adapter fork, and the second centrifugal adapter fork are all provided with through holes for inserting the pin. The reverse threaded tie rod, the waving adapter fork, and the second centrifugal adapter fork are coaxially hinged through the pin.

8. The propeller blade centrifugal and flapping load coordinating loading device according to claim 7, characterized in that, The rotating end of the reverse threaded tie rod is nested inside the waving adapter fork, and the rotating end of the waving adapter fork is nested inside the second centrifugal adapter fork.

9. The propeller blade centrifugal and flapping load coordinating loading device according to claim 2, characterized in that, The loading fixture includes: Upper and lower fixed clamps; The blade fixing block is sandwiched between the upper and lower fixing plates and has a fixing cavity that matches the shape of the blade to be loaded. One end of the blade to be loaded is engaged with the inside of the blade fixing block.

10. The propeller blade centrifugal and flapping load coordinating loading device according to claim 3, characterized in that, The centrifugal loading assembly also includes a force sensor located between the centrifugal actuator and the wire rope.

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