Large paddle fatigue test device

Abstract

The invention discloses a large paddle fatigue test device. The device comprises two bending moment applying assemblies, two movable hinge support assemblies, two centrifugal force applying assemblies and a test piece, the two bending moment applying assemblies are fixedly clamped on the test piece and are arranged along the spanwise direction of the test piece; each bending moment applying assembly is provided with a waving bending moment connector used for applying a waving bending moment in the waving direction and is provided with a shimmy bending moment connector used for applying a shimmy bending moment in the shimmy direction. The two ends of the test piece are fixedly connected with the inner ends of the movable hinge support assemblies respectively, the outer ends of the two movable hinge support assemblies are connected with the centrifugal force applying assemblies respectively, and the ends, away from the test piece, of the centrifugal force applying assemblies are fixedly connected with centrifugal force connectors used for applying centrifugal force. The large paddle fatigue test device is used for simultaneously applying a flapping bending moment and a shimmy bending moment through two bending moment applying assemblies clamped on a test piece. By adopting the fatigue test device, independent application of centrifugal force, waving bending moment and shimmy bending moment can be realized at the same time, and the requirement of a large paddle fatigue test is met.

Description

Technical Field

[0001] The present invention relates to the field of, but is not limited to, helicopter blade fatigue testing technology, and in particular to a large blade fatigue testing device. Background Art

[0002] Large blade fatigue test is an important test content in helicopter blade fatigue test technology, and has important guiding significance for the life and safety of helicopter blades. The loads that need to be applied to the entire assessment area in the large blade fatigue test include: flapping bending moment, swing bending moment and centrifugal force.

[0003] For fatigue testing of the airfoil section of the main rotor blade of a medium-sized helicopter, the general test method is to apply flapping bending moment and swing bending moment loads by exciting vibration under the condition of pre-applying centrifugal force. The load control accuracy of the above loading method is relatively low, and the risk of loading large helicopter blades is very high, so it is generally not adopted. Chinese patent application number 201210570656.8 proposes a device for applying equal bending moment in the assessment area, which uses an actuator to load equal bending moment; Chinese patent application number 201410727507.7 proposes an equal bending moment loading mechanism for anti-deicing main rotor blades; Chinese patent application number 201610149355.6 proposes an implementation plan for applying torque to anti-deicing main rotor blades at the same time, but all the above existing patents cannot apply centrifugal force loads.

[0004] In summary, in the prior art, there is no implementation scheme for fatigue testing that simultaneously applies flapping bending moment, swing bending moment and centrifugal force loads to large blades. Summary of the invention

[0005] Purpose of the present invention: In order to solve the above-mentioned problem, an embodiment of the present invention provides a large blade fatigue test device to solve the problem that in fatigue test of large blades, the conventional loading method is equal moment loading of flapping bending moment and swing bending moment, that is, the prior art lacks a fatigue test scheme for large blades that simultaneously applies flapping bending moment, swing bending moment and centrifugal force load.

[0006] The technical solution of the present invention: The embodiment of the present invention provides a large blade fatigue test device, comprising: two bending moment applying assemblies 1, two movable hinge assemblies 2, two centrifugal force applying assemblies 3 and a test piece 4;

[0007] Among them, two bending moment applying assemblies 1 are fixedly clamped on the test piece 4 and arranged along the span direction of the test piece 4; each bending moment applying assembly 1 is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction, and a swinging bending moment joint for applying a swinging bending moment in the swinging direction;

[0008] The two ends of the test piece 4 are respectively fixedly connected to the inner end of a movable hinge assembly 2, and the outer ends of the two movable hinge assemblies 2 are respectively connected to the centrifugal force applying assembly 3, and the end of the centrifugal force applying assembly 3 away from the test piece 4 is fixedly connected to a centrifugal force joint for applying centrifugal force;

[0009] The large blade fatigue test device is used to simultaneously apply flapping bending moment and swing bending moment through two bending moment applying assemblies 1 clamped on the test piece 4.

[0010] Optionally, in the large blade fatigue test device as described above,

[0011] Each of the movable hinge assembly 2 comprises: a linear guide mechanism 2a, a transverse axis 2b, a connecting member 2c and a limiting mechanism 2d;

[0012] Among them, one end of the connecting member 2c is fixedly connected to the test piece 4, and the axial hole of the other end is embedded in the centrifugal force double-ear joint 3b of the centrifugal force applying assembly 3, and the connecting member 2c and the centrifugal force double-ear joint 3b are hinged by the horizontal axis 2b; the two ends of the horizontal axis 2b are respectively installed on the symmetrically arranged linear guide mechanism 2a, so that the horizontal axis 2b slides along the direction of the linear guide mechanism 2a; the limit mechanism 2d is installed at the end of the guide close to the test piece 4 in the linear guide mechanism 2a;

[0013] The movable hinge assembly 2 connected on both sides of the test piece 4 is used to prevent the test piece 4 from deviating from the middle installation position during the test loading process through the joint action of the limiting mechanisms 2d on the linear guide mechanisms 2a on both sides.

[0014] Optionally, in the large blade fatigue test device as described above,

[0015] A radial bearing is installed in the axial hole of the connecting member 2c, so that the hinged connection between the connecting member 2c and the horizontal axis 2b has the ability to rotate in the swinging direction and the ability to swing in the swinging direction.

[0016] Optionally, in the large blade fatigue test device as described above,

[0017] In the structure of each of the movable hinged support components 2, the connecting member 2c includes: a cross joint 2e, a vertical shaft 2f, a transition piece 2g, a flange 2h and a blade joint 2j;

[0018] Among them, the inner end of the cross joint 2e is provided with a vertical axial hole, and the outer end is provided with a horizontal axial hole; the horizontal axial hole at the outer end is integrally mounted in the middle of the horizontal axis 2b, the vertical axial hole at the inner end is hinged to the double ear end of the transition piece 2g through the vertical axis 2f, the other end of the transition piece 2g is connected to one end of the blade joint 2j through the flange 2h, and the other end of the blade joint 2j is fixedly connected to one end of the test piece 4.

[0019] Optionally, in the large blade fatigue test device as described above,

[0020] In the connecting member 2c of each of the movable hinge components 2,

[0021] A hinge mechanism having the ability to freely rotate in the swinging direction is formed by the transverse axis 2b and the cross joint 2e;

[0022] A hinge mechanism having the ability to rotate freely in the swing direction is formed by the cross joint 2e, the vertical shaft 2f and the transition piece 2g;

[0023] The transition piece 2g, the flange 2h and the blade joint 2j form an installation angle adjustment mechanism for the test piece 4, which is used to meet the installation requirements when the test piece 4 has a self-twist angle.

[0024] Optionally, in the large blade fatigue test device as described above,

[0025] Each of the bending moment applying assemblies 1 comprises: a clamping mechanism 1a, a swinging linear actuator 1b and a shimmying linear actuator 1c;

[0026] Among them, the two clamping mechanisms 1a are fixedly clamped on the test piece 4 along the span direction, the swinging linear actuator 1b is hinged to the swinging bending moment joint set in the swinging direction of the clamping mechanism 1a, and the swinging linear actuator 1c is hinged to the swinging bending moment joint set in the swinging direction of the clamping mechanism 1a.

[0027] Optionally, in the large blade fatigue test device as described above,

[0028] The two bending moment applying assemblies 2 are respectively arranged on the test piece 4 from the center to the two ends, in an asymmetrical arrangement; or,

[0029] The two bending moment applying assemblies 2 are arranged on the test piece 4 at positions such that the distances from the two bending moment applying assemblies 2 to the center of the test piece 4 are the same, and the two bending moment applying assemblies 2 are symmetrically arranged.

[0030] Optionally, in the large blade fatigue test device as described above,

[0031] Each of the centrifugal force applying components 3 includes a centrifugal force linear actuator 3a and a centrifugal force double-ear joint 3b, one end of the centrifugal force double-ear joint 3b is hinged to the horizontal axis 2b of the same-side movable hinge assembly 2, and the other end is connected to the centrifugal force linear actuator 3a.

[0032] Optionally, in the large blade fatigue test device as described above,

[0033] Each of the centrifugal force applying components 3 includes a centrifugal force linear actuator 3a, and two sets of pulleys 3c and steel cables 3d; wherein the two pulleys 3c are respectively installed at the two ends of the horizontal shaft hole in the cross joint 2e extending out of the transverse axis 2b, and one end of each steel cable 3d is wound around the pulley 3c at the corresponding position, and the other end is connected to the centrifugal force linear actuator 3a.

[0034] Beneficial effects of the present invention: An embodiment of the present invention provides a large-scale blade fatigue test device, in which two bending moment applying assemblies 1 are fixedly clamped on a test piece 4 and arranged along the span direction of the test piece 4; each bending moment applying assembly 1 is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction, and is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction; the two ends of the test piece 4 are respectively fixedly connected to the inner end of a movable hinge assembly 2, the outer ends of the two movable hinge assemblies 2 are respectively connected to the centrifugal force applying assemblies 3, and the end of the centrifugal force applying assembly 3 away from the test piece 4 is fixedly connected with a centrifugal force joint for applying centrifugal force; wherein, the internal structure of the two movable hinge assemblies 2 enables them to have rotational movement ability in the swinging direction, and swing movement ability in the swinging direction. By using the large blade fatigue test device provided in the embodiment of the present invention, the flapping bending moment and the swing bending moment can be simultaneously applied through the two bending moment applying assemblies 1 clamped on the test piece 4; in addition, the large blade fatigue test device provided in the embodiment of the present invention has a compact structure and high loading accuracy, and can simultaneously realize the independent application of the flapping bending moment, the swing bending moment and the centrifugal force load, and can meet the requirements of the large blade fatigue test. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0036] Figure 1 A schematic diagram of the overall structure of a large blade fatigue test device provided by an embodiment of the present invention;

[0037] Figure 2 Another structural schematic diagram of a movable hinge assembly in a large blade fatigue testing device provided in an embodiment of the present invention.

[0038] Description of reference numerals:

[0039] 1-bending moment applying assembly, 1a-clamping mechanism, 1b-swinging linear actuator, 1c-oscillating linear actuator, 2-moving hinge assembly, 2a-linear guide mechanism, 2b-horizontal axis, 2c-connecting piece, 2d-limiting mechanism, 2e-cross joint, 2f-vertical axis, 2g-transition piece, 2h-flange, 2j-blade joint, 3-centrifugal force applying assembly, 3a-centrifugal force linear actuator, 3b-centrifugal force double-ear joint, 3c-pulley, 3d-steel cable, 4-test piece. Specific implementation plan

[0040] In order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0041] As described in the above background technology, for fatigue testing of large blades, the conventional loading method is equal moment loading of flapping moment and shimmy moment, such as several Chinese patents listed in the above background technology. In summary, there is currently no fatigue testing scheme for large blades that simultaneously applies flapping moment, shimmy moment and centrifugal force loads.

[0042] In order to solve the problem of fatigue testing of large blades, an embodiment of the present invention provides a large blade fatigue testing device.

[0043] The present invention provides the following specific embodiments which can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0044] Figure 1 The overall structure diagram of a large blade fatigue test device provided by an embodiment of the present invention is shown in FIG. Figure 1 As shown, the large blade fatigue test device provided in the embodiment of the present invention may include: two bending moment applying assemblies 1, two movable hinge assemblies 2, two centrifugal force applying assemblies 3 and a test piece 4.

[0045] like Figure 1 In the structure of the large blade fatigue test device shown, two bending moment applying assemblies 1 are fixedly clamped on the test piece 4 and arranged along the span direction of the test piece 4; each bending moment applying assembly 1 is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction, and a swinging bending moment joint for applying a swinging bending moment in the swinging direction. It should be noted that the two bending moment applying assemblies 1 can be symmetrically clamped on the test piece 4, for example, and this clamping method can be used to apply equal bending moments; and the symmetrical clamping method is not limited in the embodiment of the present invention.

[0046] In the embodiment of the present invention, the two ends of the test piece 4 are respectively fixedly connected to the inner end of a movable hinge assembly 2, the outer ends of the two movable hinge assemblies 2 are respectively connected to the centrifugal force applying assembly 3, and the end of the centrifugal force applying assembly 3 away from the test piece 4 is fixedly connected with a centrifugal force joint for applying centrifugal force.

[0047] The large blade fatigue test device provided in the embodiment of the present invention can simultaneously apply the flapping bending moment and the swing bending moment through the two bending moment applying assemblies 1 clamped on the test piece 4.

[0048] In an optional implementation of the embodiment of the present invention, an implementation structure of the mobile hinge assembly 2 is provided, such as Figure 1 As shown, each movable hinge assembly 2 includes: a linear guide mechanism 2a, a transverse axis 2b, a connecting member 2c and a limiting mechanism 2d.

[0049] Reference Figure 1 and Figure 2 As shown, one end of the connecting member 2c is fixedly connected to the test piece 4, and the axial hole of the other end is embedded in the centrifugal force double-ear joint 3b of the centrifugal force application assembly 3, and the axial hole of the connecting member 2c and the centrifugal force double-ear joint 3b are hinged by the transverse axis 2b; in addition, the two ends of the transverse axis 2b are respectively installed on the symmetrically arranged linear guide mechanisms 2a, so that the transverse axis 2b slides along the direction of the linear guide mechanism 2a; a limiting mechanism 2d is installed at the end of the guide close to the test piece 4 in the linear guide mechanism 2a.

[0050] In this implementation, the movable hinge assembly 2 connected to the two sides of the test piece 4 is used to prevent the test piece 4 from deviating from the middle installation position during the test loading process through the combined action of the limiting mechanisms 2d on the linear guide mechanisms 2a on both sides.

[0051] It should be noted that the hinged connection between the connecting member 2c and the horizontal axis 2b in this implementation is such that the connecting member 2c can rotate freely in both the swinging direction and the shimmying direction. The implementation is such that a radial bearing is installed in the shaft hole of the connecting member 2c, so that the hinged connection between the connecting member 2c and the horizontal axis 2b has the ability to rotate in the swinging direction and the ability to swing in the shimmying direction.

[0052] In another optional implementation of the embodiment of the present invention, another implementation structure of the mobile hinge assembly 2 is provided, such as Figure 2 FIG. 1 is another schematic diagram of the structure of the movable hinge assembly in the large blade fatigue test device provided by the embodiment of the present invention. Figure 1 Based on the structure of the movable hinge assembly 2 shown, the connecting member 2c includes: a cross joint 2e, a vertical shaft 2f, a transition piece 2g, a flange 2h and a blade joint 2j.

[0053] In this implementation, a vertical axial hole is provided at the inner end of the cross joint 2e, and a horizontal axial hole is provided at the outer end; the horizontal axial hole at the outer end is integrally mounted in the middle of the horizontal axis 2b, the vertical axial hole at the inner end is hinged to the double ear end of the transition piece 2g through the vertical axis 2f, the other end of the transition piece 2g is connected to one end of the blade joint 2j through the flange 2h, and the other end of the blade joint 2j is fixedly connected to one end of the test piece 4.

[0054] The structure of the connecting member 2c of the movable hinge assembly 2 provided in this implementation method includes, on the one hand, an articulated mechanism that can rotate freely in the swinging direction, specifically, an articulated mechanism with free rotation ability in the swinging direction is formed by the horizontal axis 2b and the cross joint 2e; on the other hand, it also includes an articulated mechanism that can rotate freely in the swinging direction, specifically, an articulated mechanism with free rotation ability in the swinging direction is formed by the cross joint 2e, the vertical axis 2f and the transition piece 2g; on the other hand, the connecting member 2c includes a test piece installation angle adjustment mechanism, specifically, an installation angle adjustment mechanism of the test piece 4 is formed by the transition piece 2g, the flange 2h and the blade joint 2j, which is used to meet the installation requirements when the test piece 4 has a self-twist angle.

[0055] In one implementation of the embodiment of the present invention, Figure 1 As shown, each bending moment applying assembly 1 includes: a clamping mechanism 1a, a swinging linear actuator 1b and a shimmying linear actuator 1c.

[0056] In this implementation, the two clamping mechanisms 1a are fixedly clamped on the test piece 4 along the span direction, the swinging linear actuator 1b is hinged to the swinging bending moment joint set in the swinging direction of the clamping mechanism 1a, and the swinging linear actuator 1c is hinged to the swinging bending moment joint set in the swinging direction of the clamping mechanism 1a.

[0057] The large blade fatigue test device provided by this implementation can simultaneously apply flapping bending moment and swing bending moment through two bending moment applying assemblies 1 clamped on the test piece 4.

[0058] In a specific implementation, the two bending moment applying assemblies 2 may be arranged at:

[0059] Example 1: Two bending moment applying assemblies 2 are respectively arranged on the test piece 4 from the center position to the two ends, which is an asymmetrical arrangement.

[0060] Example 2: Two bending moment applying assemblies 2 are arranged on the test piece 4 so that the distances between the two bending moment applying assemblies 2 and the center of the test piece 4 are the same, which is a symmetrical arrangement.

[0061] In an optional implementation of the embodiment of the present invention, as Figure 1As shown, each of the centrifugal force applying components 3 includes a centrifugal force linear actuator 3a and a centrifugal force double-ear joint 3b, one end of the centrifugal force double-ear joint 3b is hinged to the horizontal axis 2b of the movable hinge assembly 2 on the same side, and the other end is connected to the centrifugal force linear actuator 3a.

[0062] In another optional implementation of the embodiment of the present invention, in the above Figure 2 Based on the structure of the movable hinge assembly 2 shown, the centrifugal force double-ear joint 3b includes: a centrifugal force linear actuator 3a, and two sets of pulleys 3c and steel cables 3d; wherein the two pulleys 3c are respectively installed at the two ends of the horizontal shaft hole in the cross joint 2e extending from the horizontal axis 2b, one end of each steel cable 3d is wound around the pulley 3c at the corresponding position, and the other end is connected to the centrifugal force linear actuator 3a.

[0063] A large-scale blade fatigue test device provided by an embodiment of the present invention comprises two bending moment applying assemblies 1 fixedly clamped on a test piece 4 and arranged along the span direction of the test piece 4; each bending moment applying assembly 1 is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction, and a swinging bending moment joint for applying a swinging bending moment in the swinging direction; both ends of the test piece 4 are respectively fixedly connected to the inner end of a movable hinge assembly 2, the outer ends of the two movable hinge assemblies 2 are respectively connected to a centrifugal force applying assembly 3, and the end of the centrifugal force applying assembly 3 away from the test piece 4 is fixedly connected to a centrifugal force joint for applying a centrifugal force; wherein, the internal structure of the two movable hinge assemblies 2 enables them to have rotational movement capability in the swinging direction, and swinging movement capability in the swinging direction. By using the large blade fatigue test device provided in the embodiment of the present invention, the flapping bending moment and the swing bending moment can be simultaneously applied through the two bending moment applying assemblies 1 clamped on the test piece 4; in addition, the large blade fatigue test device provided in the embodiment of the present invention has a compact structure and high loading accuracy, and can simultaneously realize the independent application of the flapping bending moment, the swing bending moment and the centrifugal force load, and can meet the requirements of the large blade fatigue test.

[0064] The implementation of the large blade fatigue testing device provided by the present invention is schematically described below through several specific embodiments.

[0065] Embodiment 1:

[0066] like Figure 1 As shown, in this embodiment, the test piece 4 is the main blade, with its center as the origin, the short side as the X-axis, the upward direction as the Z-axis, and the direction perpendicular to the X-axis and Z-axis as the Y-axis, to schematically illustrate the large blade fatigue test device. In this embodiment 1, the flapping bending moment is the bending moment of rotation around the X-axis, the swing bending moment is the bending moment of rotation around the Z-axis, and the centrifugal force is the tensile load in the Y-axis direction.

[0067] refer to Figure 1, the two bending moment applying assemblies 1 are symmetrically distributed in the Y-axis direction, and are respectively arranged on the test piece 4 from the center to the two ends, and the distances between the two bending moment applying assemblies 1 and the center of the test piece 4 are the same. Each bending moment applying assembly 1 includes a set of clamping mechanism 1a, a swinging linear actuator 1b and a swinging linear actuator 1c. The clamping mechanism 1a is fixed on the test piece 4, the swinging linear actuator 1b is hinged on the clamping mechanism 1a along the Z-axis direction, and the swinging linear actuator 1c is hinged on the clamping mechanism 1a along the X-axis direction. The ends of the swinging linear actuator 1b and the swinging linear actuator 1c away from the clamping mechanism 1a are connected and fixed in a conventional manner. In this embodiment, the swinging linear actuator 1b and the swinging linear actuator 1c are both actuators, and can also be other load application methods, such as motors, electromagnetics, etc.

[0068] The two movable hinge assemblies 2 are symmetrically distributed in the Y-axis direction, and each movable hinge assembly 2 is symmetrical in the front and back direction of the X-axis, and includes a linear guide mechanism 2a, a transverse axis 2b, a connecting member 2c and a limiting mechanism 2d. The two ends of the transverse axis 2b are respectively fixedly mounted on the sliders of the linear guide mechanisms 2a on both sides. It can be understood that if there are two sliders on the linear guide mechanism 2a on one side, the fixed connection between the transverse axis 2b and multiple sliders can be achieved by adding a transition plate. One end of the connecting member 2c is connected to the fixed support of the test piece, and the other end is hinged to the middle of the transverse axis 2b. It can be understood that in order to reduce friction resistance, a bearing can be installed between the connecting member 2c and the transverse axis 2b. In this embodiment, in order to achieve the free rotation of the connecting member 2c relative to the transverse axis 2b in the swinging direction and the swinging direction, a radial bearing or a spherical bearing must be selected. The limiting mechanism 2d is located on the guide rail of the linear guide mechanism 2a on one side close to the test piece 4. The purpose of setting the limiting mechanism 2d is to prevent the test piece from gradually deviating to one side while ensuring the free movement of the test piece in the Y-axis direction during the fatigue test.

[0069] The two centrifugal force applying components 3 are symmetrically distributed along the Y-axis direction on the side of the movable hinge component 2 away from the test piece 4, and include a centrifugal force linear actuator 3a and a centrifugal force double-ear joint 3b. One end of the centrifugal force double-ear joint 3b is hinged to the outside of the connecting piece 2c on the horizontal axis 2b, and one end is connected to the centrifugal force linear actuator 3a. The end of the centrifugal force linear actuator 3a away from the centrifugal force double-ear joint 3b is connected and fixed in a conventional manner. It can be understood that in order to reduce friction resistance, a rolling bearing can also be installed between the centrifugal force double-ear joint 3b and the horizontal axis 2b.

[0070] Embodiment 2:

[0071] The principle is similar to that of embodiment 1, except that the connecting member 2c includes a hinge mechanism that can rotate freely in the swing direction and a test piece installation angle adjustment mechanism. Figure 2, Figure 1 The connecting member 2c in the embodiment 1 shown is replaced by: a cross joint 2e, a vertical axis 2f, a transition piece 2g, a flange 2h and a blade joint 2j. Among them, one end of the cross joint 2e is hinged to the middle of the horizontal axis 2b, and the other end is hinged to the double ear end of the transition piece 2g through the vertical axis 2f. The other end of the transition piece 2g is connected to one end of the blade joint 2j through the flange 2h, and the other end of the blade joint 2j is connected to the fixed support of the test piece. In this embodiment 2, the horizontal axis 2b and the cross joint 2e form an articulated mechanism with free rotation ability in the swing direction; the cross joint 2e, the vertical axis 2f and the transition piece 2g form an articulated mechanism that can rotate freely in the swing direction. The existence of this articulated mechanism reduces the friction resistance and bearing load state of the entire mobile hinge assembly 2; the transition piece 2g, the flange 2h and the blade joint 2j form a test piece installation angle adjustment mechanism, which can meet the installation requirements when the test piece 4 has a self-twist angle. In addition, in this embodiment 2, in order to improve the load-bearing capacity of the linear guide mechanism 2a, the number of guide rails and sliders is increased; in order to prevent the centrifugal force linear actuator 3a from pushing up and causing damage to the test piece 4, the centrifugal force double-ear joint 3b is replaced by a combination of a pulley 3c and a steel cable 3d, and the pulleys 3c are respectively installed at the two ends of the horizontal shaft hole in the cross joint 2e extending out of the horizontal axis 2b, and one end of each steel cable 3d is wound around the pulley 3c, and the other end is connected to the centrifugal force linear actuator 3a.

[0072] Although the embodiments disclosed in the present invention are as above, the contents are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A large blade fatigue test device, characterized in that: include: Two bending moment applying assemblies (1), two movable hinge assemblies (2), two centrifugal force applying assemblies (3) and a test piece (4); Wherein, two bending moment applying assemblies (1) are fixedly clamped on the test piece (4) and arranged along the span direction of the test piece (4); each bending moment applying assembly (1) is provided with a swinging bending moment joint for applying a swinging bending moment in the swinging direction, and a swinging bending moment joint for applying a swinging bending moment in the swinging direction; The two ends of the test piece (4) are respectively fixedly connected to the inner end of a movable hinge assembly (2), the outer ends of the two movable hinge assemblies (2) are respectively connected to the centrifugal force applying assembly (3), and the end of the centrifugal force applying assembly (3) away from the test piece (4) is fixedly connected to a centrifugal force joint for applying centrifugal force; The large blade fatigue test device is used to simultaneously apply a flapping bending moment and a shimmy bending moment through two bending moment applying assemblies (1) clamped on a test piece (4).

2. The large blade fatigue test device according to claim 1, characterized in that: Each of the movable hinge components (2) comprises: a linear guide mechanism (2a), a transverse axis (2b), a connecting member (2c) and a limiting mechanism (2d); One end of the connecting member (2c) is fixedly connected to the test piece (4), and the axial hole of the other end is embedded in the centrifugal force double-ear joint (3b) of the centrifugal force applying assembly (3), and the connecting member (2c) and the centrifugal force double-ear joint (3b) are hingedly connected by a transverse axis (2b); the two ends of the transverse axis (2b) are respectively mounted on symmetrically arranged linear guide mechanisms (2a), so that the transverse axis (2b) slides along the direction of the linear guide mechanism (2a); and a limiting mechanism (2d) is installed at one end of the guide close to the test piece (4) in the linear guide mechanism (2a); The movable hinge assembly (2) connected to the two sides of the test piece (4) is used to prevent the test piece (4) from deviating from the middle installation position during the test loading process through the joint action of the limiting mechanisms (2d) on the linear guide mechanisms (2a) on both sides.

3. The large blade fatigue test device according to claim 2, characterized in that: A radial bearing is installed in the shaft hole of the connecting member (2c), so that the hinged connection between the connecting member (2c) and the horizontal axis (2b) has the ability to rotate in the swinging direction and the ability to swing in the swinging direction.

4. The large blade fatigue test device according to claim 2, characterized in that: In the structure of each movable hinge assembly (2), the connecting member (2c) includes: a cross joint (2e), a vertical shaft (2f), a transition piece (2g), a flange (2h) and a blade joint (2j); The inner end of the cross joint (2e) is provided with a vertical axis hole, and the outer end is provided with a horizontal axis hole; the horizontal axis hole at the outer end is integrally mounted in the middle of the horizontal axis (2b); the vertical axis hole at the inner end is hinged to the double ear end of the transition piece (2g) through the vertical axis (2f); the other end of the transition piece (2g) is connected to one end of the blade joint (2j) through a flange (2h), and the other end of the blade joint (2j) is fixedly connected to one end of the test piece (4).

5. The large blade fatigue testing device according to claim 4, characterized in that: In the connecting member (2c) of each of the movable hinge assemblies (2), A hinge mechanism having the ability to rotate freely in the swinging direction is formed by the transverse axis (2b) and the cross joint (2e); A hinge mechanism having the ability to rotate freely in the swing direction is formed by the cross joint (2e), the vertical shaft (2f) and the transition piece (2g); A mounting angle adjustment mechanism of the test piece (4) is formed by a transition piece (2g), a flange (2h) and a blade joint (2j), and is used to meet the installation requirements when the test piece (4) has a self-twist angle.

6. The large blade fatigue testing device according to claim 1, characterized in that: Each of the bending moment applying assemblies (1) comprises: a clamping mechanism (1a), a swinging linear actuator (1b) and a shimmying linear actuator (1c); The two clamping mechanisms (1a) are fixedly clamped on the test piece (4) along the span direction, the swinging linear actuator (1b) is hingedly connected to a swinging bending moment joint provided in the swinging direction of the clamping mechanism (1a), and the swinging linear actuator (1c) is hingedly connected to a swinging bending moment joint provided in the swinging direction of the clamping mechanism (1a).

7. The large blade fatigue test device according to claim 6, characterized in that: The two bending moment applying assemblies (2) are respectively arranged on the test piece (4) from the center to the two ends, in an asymmetrical arrangement; or, The two bending moment applying assemblies (2) are arranged at positions on the test piece (4) such that the distances between the two bending moment applying assemblies (2) and the center of the test piece (4) are the same, thus forming a symmetrical arrangement.

8. The large blade fatigue testing device according to any one of claims 1 to 7, characterized in that: Each of the centrifugal force applying components (3) comprises a centrifugal force linear actuator (3a) and a centrifugal force double-ear joint (3b); one end of the centrifugal force double-ear joint (3b) is hinged to the horizontal axis (2b) of the movable hinge assembly (2) on the same side, and the other end is connected to the centrifugal force linear actuator (3a).

9. The large blade fatigue test device according to any one of claims 4 to 7, characterized in that: Each of the centrifugal force applying components (3) comprises a centrifugal force linear actuator (3a), and two sets of pulleys (3c) and steel cables (3d); wherein the two pulleys (3c) are respectively mounted on the two ends of the horizontal shaft hole in the cross joint (2e) extending out of the transverse shaft (2b), and one end of each steel cable (3d) is wound around the pulley (3c) at the corresponding position, and the other end is connected to the centrifugal force linear actuator (3a).

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