KR100898488B1 - Tension-torsion strap test device for tiltrotor hub - Google Patents

Abstract

A load testing apparatus for a tension-torsion strap mounted on a tilt rotor hub of an aircraft, the apparatus comprising: a housing which forms an appearance and is connected to both sides of the tension-torsion strap and a housing in which the tension-torsion strap is received; A tensile load applying unit for applying a tensile load to the torsional load, a torsional load applying unit connected to one side of the tension-torsion strap to apply a torsional load to the tension-torsion strap, and the tensile load application unit Provided is a test apparatus including a first measuring unit for measuring and the second measuring unit provided in the torsional load applying unit to measure the torsional load. Therefore, it is possible to simultaneously measure the tensile strength and the torsional load and the strength of the tensile-torsion strap in one test apparatus, and the tensile strength and the torsional strength can be measured accurately and easily.

Tilt rotor, tensile-torsion straps, tensile strength test, torsional load and strength test

Description

Tension-torsion strap testing device for tilt rotor hubs {TENSION-TORSION STRAP TEST DEVICE FOR TILTROTOR HUB}

1 is a perspective view for explaining an example of a tilt rotor hub device;

2 is a cross-sectional view of the hub device of FIG. 1;

3 is a perspective view for explaining the tension-torsion strap of the hub device of FIG.

Figure 4 is a perspective view for explaining the test device of the tension-torsion strap according to an embodiment of the present invention;

5 is a plan view of the test apparatus of FIG. 4;

6 is a cross-sectional view for explaining a tensile load applying unit in the test apparatus of FIG.

7 is a perspective view for explaining a torsional load applying unit in the test apparatus of FIG.

FIG. 8 is a front view illustrating main parts for explaining the torsional load applying unit of FIG. 7. FIG.

<Explanation of symbols for the main parts of the drawings>

10: Test apparatus 11: Housing

100: tension-torsion strap 120: hub flexure

200: tensile load applying unit 201: fixing pin

210: first measuring part 221, 223: holder part

230: tension control unit 231: screw

235: handle 250: bearing part

251: bearing housing 300: torsional load application

310: second measurement unit 321: first link

325: third link 330: torsion adjusting unit

331: second link 332: second guide

333: support 334: first guide

The present invention relates to a load testing device for a tension-torsion strap, and more particularly, to a testing device for testing the tensile strength and torsional load and strength of the tension-torsion strap for hubs of helicopters or tilt rotors.

Rotor-manned and unmanned aerial vehicles and R / C model aircraft fly using the lift generated by the blades through the rotational force generated from the rotating rotor shaft. Lifting occurs by adjusting the angle of attack of the blade, that is, the angle between the baseline of the blade and the air flow.

Since the blade adjusts the angle while rotating about the rotor axis, the blade has a structure that can be connected to the hub device to allow free angle adjustment.

The connection between the blade and the hub device is made in a variety of ways, but for rotors designed to have a simple structure, the hub flexure and pitch case are centered. The hub flexure and pitch case are finally connected via a tension-torsion strap (TTS) to withstand tension and torsion due to blade rotation.

Here, the hub flexure and the tension-torsion strap are structures necessary for the adjustment of the angle of attack required for the rotational movement of the blade, and when the blade is fixed to the pitch case without the hub flexure and the tension-torsion strap, the centrifugal force generated by the rotation of the rotor shaft can withstand. But the angle of attack cannot be adjusted.

The tension-torsion strap serves to secure the hub flexure and pitch case against the centrifugal force caused by the rotor shaft rotation, and to withstand the torsional moment load of the rotating blade by the blade angle of attack, and to return it to its original position after offsetting the angle of attack. It also plays a role.

In other words, the tension-torsion strap is made of a material that is elastic so that the hub device can be restored to its original shape when both tension and torsional loads are canceled while simultaneously bearing tensile and torsional loads. Tensile-torsion straps generally use metal wires to achieve the strength and elasticity of performance required by hub devices. Since the tension-torsion straps are formed of bundles of wires, an appropriately sized tensile load is applied to the tension-torsion straps to keep the wire bundles wound around the tension-torsion straps. In other words, the wire is restored to its original shape due to the elastic force of the wire itself, and the wire wound on the tension-torsion strap is in contact with the inside of the hub flexure. To solve this problem, the hub flexure generally has a length that allows the tension-torsion strap to remain straight inside the pitch case.

Tensile-torsion straps are components that withstand the large centrifugal forces generated in the blades and are important components that are directly related to aircraft accidents in the event of a breakdown.

For tilt rotors, a pitch angle of up to 60 degrees is required, which requires a minimum of 30 degrees of torsion of the tension-torsion strap. In addition, the restoring force of the tension-torsion strap increases in proportion to the torsion angle, and in the case of the tilt rotor, this restoring force accounts for a large proportion of the pitch link load. Therefore, in the case of the tension-torsion strap for the tilt rotor, not only the tensile load test but also the torsion load test and the torsional strength test for the torsional load are required. Especially for unmanned aerial vehicles using electro-servo actuators, torsional load testing of tension-torsion straps is mandatory due to limited actuator loading capacity.

In general, a tensile test apparatus for strength test for a large tensile load is applied to the tensile load by using a hydraulic pressure, a configuration of this type of test device requires a very complicated and expensive hydraulic system.

In addition, in order to apply the tension test device using the hydraulic pressure to the torsion test, a separate additional device for the torsion test is required, and the test device using the hydraulic pressure can be tested only in a limited place where the hydraulic system is installed. There is an inefficient problem.

Therefore, the present invention is to solve the above problems,

It is an object of the present invention to provide a test apparatus for a tension-torsion strap for a tilt rotor hub capable of simultaneously performing a tensile strength test and a torsion test of a tension-torsion strap, which is a key component of the tilt rotor hub.

Another object of the present invention is a load testing apparatus for a tension-torsion strap for a tilt rotor hub having excellent mobility and utility by applying a simple mechanism for converting a bolt's rotational force into a tensile force instead of an expensive and complicated hydraulic system test apparatus. To provide.

Another object of the present invention is to provide a test apparatus for a tension-torsion strap for a tilt rotor hub that can be directly utilized not only for the tilt rotor, but also for structural testing of a tension-torsion strap for a general helicopter.

Still another object of the present invention is to provide a test apparatus for a tension-torsion strap for a tilt rotor hub, by applying a thrust bearing, thereby reducing frictional force due to tensile force, thereby making it possible to easily measure the pure restoring force of the tension-torsion strap.

A load testing apparatus for a tension-torsion strap mounted on a tilt rotor hub of an aircraft of the present invention includes a housing for forming an exterior, and a housing in which the tension-torsion strap is accommodated, and connected to both sides of the tension-torsion strap. A tensile load applying unit for applying a tensile load to the torsion strap, a torsion load applying unit connected to one side of the tension-torsion strap to apply a torsion load to the tension-torsion strap, and provided in the tensile load application unit It includes a first measuring unit for measuring the load and the second measuring unit for measuring the torsional load provided in the torsional load applying unit.

In an embodiment, at least one of the first measuring unit and the second measuring unit preferably uses a load cell.

In an embodiment, the tensile load applying portion is coupled to the holder portion for securing both ends of the tension-torsion strap and the holder portion along the axial direction of the tension-torsion strap and applied to the tension-torsion strap by rotation. It comprises a tension control for varying the magnitude of the tensile force. Here, the tension load applying unit may be screwed to the holder portion and the tension control portion so that the holder portion can be linearly moved by the rotation of the tension control portion.

In an embodiment, the first measuring unit may be provided at an end of the tension-torsion strap opposite the tension control unit so as to measure the tensile deformation of the tension-torsion strap.

In an embodiment, the tensile load applying unit may be provided with a bearing unit for supporting the axial frictional force of the tension-torsion strap when the torsional load is applied. For example, the bearing part may be provided in the holder part. In addition, the bearing portion preferably uses a thrust bearing to support the axial load.

In an embodiment, the torsional load applying portion is connected to the holder portion. Here, the torsional load applying unit is connected to the torsion control unit for varying the torsional load applied to the tension-torsion strap and the torsion control unit and the tension load application unit respectively to apply a torsional load to the tension-torsion strap It is configured to include a first link for.

For example, the torsion adjustment unit, a torsion angle adjustment unit formed with a first guide for adjusting the torsion angle of the tension-torsion strap, one end is connected to the first link, the other end is rotated to the torsion angle adjustment unit It may be configured to include a second link that is possibly coupled to the second link and provided on the second link, to secure the second link as selectively coupled to the first guide. Here, the second guide may be a quick release pin.

In an embodiment, the first link and the second link may be disposed in parallel so as to easily adjust the torsional load applied to the tension-torsion strap. The second measurement unit may be provided between the first link and the second link.

Therefore, the tensile strength test and the torsion load and the strength test of the tension-torsion strap can be performed at the same time, the load can be applied in a simple structure has the advantage of excellent mobility and utilization of the test apparatus.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited or limited by the embodiments.

First, the tilt rotor hub and the tension-torsion strap will be described in detail with reference to FIGS. 1 to 3.

1 is a perspective view for explaining an example of a hub device having a tension-torsion strap, Figure 2 is a cross-sectional view of the hub device of Figure 1, Figure 3 is a perspective view for explaining a tension-torsion strap.

Referring to the drawings, the hub device 1 includes a hub flexure 120 fixed to a rotor 160 shaft, a pitch case 151 connected to a blade 150, the hub flexure 120 and the pitch case. Consisting of a tension-torsion strap 100 connecting 151.

The hub flexure 120 is fixed to the shaft of the rotor 160, and a predetermined space is formed inside the hub flexure 120 to enable the tension-torsion strap 100 to be fixed. In addition, the hub flexure 120 and the tension-torsion strap 100 is coupled with a pin.

The pitch case 151 is mounted on the opposite side of the tension-torsion strap 100 inserted into the hub flexure 120. In addition, the pitch case 151 and the tension-torsion strap 100 are also coupled using a pin.

As shown in FIG. 2, the rotor 160 is connected to the hub flexure 120 and the pitch case 151, respectively, and the hub flexure 120 is connected to the blade 150. The rotational force of the rotor 160 is transmitted to the blade 150 through the pitch case 151, the tension-torsion strap 100, and the hub flexure 120.

That is, the blade 150 rotates due to the rotational force transmitted from the rotor 160. Here, as the blade 150 rotates, the tensile-torsion strap 100 is applied with a tensile load in the centrifugal force direction, and a torsional load is applied by adjusting the angle of attack of the blade 150.

As shown in FIG. 3, the tension-torsion strap 100 is a component that transmits the tensile load and the torsional load between the rotor 160 and the blade 150, and has a predetermined tensile strength and torsional strength. It is formed of a material and structure. For example, the tension-torsion strap 100 may be a metal wire. In addition, the tension-torsion strap 100 may be formed by winding a plurality of metal wires. Here, the metal wire may be formed of various metal materials, but generally a metal material may be used.

Here, the shape and material of the tension-torsion strap 100 is not limited thereto, and may be manufactured according to the design requirements of the shape, tension and torsional load of the hub device 1.

On the other hand, the tension-torsion strap 100 has a structure that can transfer the tensile load and the torsional load between the rotor 160 and the blade 150. In addition, the tensile-torsion strap 100 requires a predetermined strength capable of withstanding a tensile load and a torsional load of a predetermined size or more. Therefore, a test apparatus for measuring the tensile strength and the torsional load of the tension-torsion strap 100 is required. In addition, it will further be required to measure the torsional strength against the torsional load of the tension-torsion strap 100.

Hereinafter, a test apparatus 10 for a tension-torsion strap for a tilt rotor hub according to an embodiment of the present invention will be described in detail with reference to FIGS. 4 to 8.

Referring to the drawings, the test device 10 for the strength test of the tension-torsion strap 100 is a housing 11, and a tensile load applying unit for measuring the tensile strength of the tension-torsion strap 100 ( 200, and a torsional load applying unit 300 for measuring the torsional load and the strength of the tension-torsion strap 100.

The housing 11 forms an appearance of the test apparatus 10 and supports the load of the tensile load applying unit 200 and the torsional load applying unit 300. For example, the housing 11 may have a box shape to simplify the structure of the test apparatus 10 and improve mobility.

The tensile load applying unit 200 is provided in the housing 11 and is mounted at both ends of the tension-torsion strap 100. The tensile load applying unit 200 includes a holder unit 221, 223, a tension adjusting unit 230, and a first measuring unit 210 for measuring the magnitude of the tensile load applied to the tension-torsion strap 100. do.

The holder parts 221 and 223 are coupled to both ends of the tension-torsion strap 100 to fix the tension-torsion strap 100. For example, the holder parts 221 and 223 and the tension-torsion strap 100 are coupled by the fixing pin 201.

In addition, the holder parts 221 and 223 transmit a tensile load from the tension adjusting part 230 to the tension-torsion strap 100. For example, the holder parts 221 and 223 are coupled to the first holder 221 fixed to the housing 11 and the tension control part 230 and moved by the tension control part 230. And a second holder 223 for causing tensile strain in the tension-torsion strap 100.

The tension control unit 230 is coupled along the axial direction of the tension-torsion strap 100 to adjust the magnitude of the tensile load applied to the tension-torsion strap 100 by rotation. For example, the tension control unit 230 may be a screw 231. In addition, it may include a handle 235 for generating the rotation of the screw 231. That is, as the screw 231 is rotated, the second holder 223 moves along the axial direction of the tension-torsion strap 100, and tensile deformation occurs in the tension-torsion strap 100. . In addition, by adjusting the rotational speed of the screw 231 by using the handle 235, the tensile strain of the tension-torsion strap 100 is adjusted, and as a result is applied to the tension-torsion strap 100 The magnitude of the tensile load can be adjusted.

Here, it is preferable that the tension adjusting unit 230 uses a screw 231 having a fine pitch to finely adjust the magnitude of the tensile load applied to the tension-torsion strap 100 as much as possible.

The first measuring unit 210 may be a load cell measuring a tensile load applied to the tension-torsion strap 100 by using the tensile deformation of the tension-torsion strap 100. In addition, the first measuring unit 210 may be provided between the first holder 221 and the housing 11 to accurately measure the tensile deformation of the tension-torsion strap 100.

The torsional load applying unit 300 is a second measurement unit 310 for measuring the magnitude of the torsional load applied to the first link 321, the torsion control unit 330 and the tension-torsion strap 100. It includes.

Here, the torsional load applying unit 300 is connected to the tensile load applying unit 200. Therefore, the test apparatus 10 can simultaneously measure the tensile strength and the torsional load and thus the torsional strength of the tensile-torsion strap 100 in the same test apparatus 10.

For example, the first link 321 is connected to the second holder 223. In detail, as shown in FIG. 7 or 8, the first link 321 generates a torsional deformation in the tension-torsion strap 100 as it is rotated by the tension control unit 230. Here, the first link 321 preferably has a strength of a predetermined size or more so as to transmit a large torsional load to the tension-torsion strap 100. In addition, the coupling structure of the first link 321 and the second holder 223 can also easily transfer the torsional load, as well as deformation does not occur due to the torsional load transmitted to the tension-torsion strap 100. It is desirable to have a structure that does not. For example, the first link 321 may be accommodated and fixed through the second holder 223.

The torsion adjusting unit 330 is connected to the first link 321 so as to apply a torsional load to the tension-torsion strap 100 as the first link 321 rotates ( 331, and a support 333 rotatably provided with the second link 331. For example, the support part 333 may have a plate shape fixed to one surface of the housing 11, and the second link 331 may be rotatable along the surface of the support part 333. One end may be hinged.

The support 333 may be provided with a first guide 334 for guiding the rotation angle θ of the second link 331. The first guide 334 may be a plurality of holes formed in the support part 333 at equal intervals. For example, the first guide 334 may be a plurality of holes formed at equal intervals on a circumference around an axis where the second link 331 is hinged to the support 333. In addition, a second guide 332 for fixing the second link 331 by being selectively coupled to one of the first guide 334 corresponding to the first guide 334 on the second link 331. ) May be provided. For example, the second guide 332 may be a quick release pin. That is, in a state in which the second guide 332 is released from the first guide 334, the second link 331 may be rotated, and the second guide 332 may be rotated by the first guide 334. Since the second link 331 is fixed by insertion into one of the two links, the torsional load can be easily applied and adjusted to the tension-torsion strap 100.

On the other hand, the first link 321 and the second link 331 is preferably arranged in parallel. As shown in FIG. 8, as the first link 321 and the second link 331 are disposed in parallel, the first link (even when the torsional deformation occurs in the tension-torsion strap 100). 321 and the second link 331 are always kept in a parallel state. Accordingly, the rotation angle θ of the first link 321 may be easily determined through the rotation angle θ of the second link 331. In addition, since the rotation angle θ of the first link 321 is a torsional deformation of the tension-torsion strap 100, as a result, the torsional load applied to the tension-torsion strap 100 can be measured easily and accurately. can do.

Here, the second measuring unit 310 may be a load cell measuring a torsional load applied to the tension-torsion strap 100 by using the torsional deformation of the tension-torsion strap 100. In addition, the second measuring unit 310 is provided between the first link 321 and the torsion adjusting unit 330. In particular, the first link 321 and the second link 331 are arranged in parallel, and the second measuring unit 310 connects the first link 321 and the second link 331. It may be provided on the third link 325.

That is, the third linking centers of rotation of the first link 321 and the second link 331 are arranged on the same line and horizontally connecting the first link 321 and the second link 331. The second measuring unit 310 may be provided on the link 325. Accordingly, the third link 325 may maintain a horizontal state even when the first link 321 and the second link 331 are rotated so that the tension-torsion strap 100 has a torsional deformation. Here, the torsional moment applied to the tension-torsion strap 100 is a torsional load applied to the tension-torsion strap 100 and the distance between the torsion adjusting unit 330 and the tension-torsion strap 100 Can be obtained as a product. That is, since the second measuring unit 310 has a difference of 90 ° compared with the rotation angle θ of the first link 321, the torsional moment applied to the tension-torsion strap 100 is determined by the first measurement. 2 can be obtained as the product of the torsional load value measured by the measurement unit 310 and the cosine θ (cos (θ)) value.

Meanwhile, when the torsional load is applied to the tensile load applying unit 200 while the tensile load is applied to the tension-torsion strap 100, the tension-torsion strap 100 is applied to accurately apply the torsional load. The torsional frictional forces of the system should be minimized. Therefore, the tensile load applying unit 200 is provided with a bearing portion 250 for minimizing the axial frictional force of the tension-torsion strap 100. For example, the bearing part 250 may be provided in the second holder 223 to which the torsional load applying part 300 is connected, and may be a thrust bearing. Here, the second holder 223 may be integrally formed with the bearing housing 251 of the bearing part 250.

Therefore, the test apparatus 10 may apply a torsional load in a state where a tensile load is applied to the tension-torsion strap 100, and adjust the magnitude of the applied torsional load. Similarly, the test apparatus 10 may apply a tensile load to the tension-torsion strap 100 while the torsional load is applied to the tension-torsion strap 100, and adjust the magnitude of the applied tension load. .

As described above, according to the present invention, first, there is an effect that can be performed at the same time the tensile strength test and the torsion test of the tension-torsion strap, which is a key component of the tilt rotor hub.

Second, the present invention is excellent in mobility and usability by applying a simple mechanism for converting the rotational force of the bolt to the tensile force in place of the test device by the expensive and complicated hydraulic system.

Third, the present invention can be directly used not only for tilt rotors, but also for structural tests of tension-torsion straps for general helicopters.

Fourth, the present invention reduces the frictional force by the tensile force by applying the thrust bearing, it is easy to measure the pure restoring force of the tension-torsion strap.

As described above, although described with reference to the preferred embodiment of the present invention, those skilled in the art various modifications and variations of the present invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (14)

In the load test device of the tension-torsion strap mounted on the tilt rotor hub of the aircraft, A housing defining an appearance and containing the tension-torsion strap; A tensile load applying unit connected to both sides of the tension-torsion strap to apply a tensile load to the tension-torsion strap; A torsional load applying unit connected to one side of the tension-torsion strap to apply a torsional load to the tension-torsion strap; A first measuring unit provided in the tensile load applying unit to measure a tensile load; And A second measuring unit provided at the torsional load applying unit to measure the torsional load; Including, The torsional load applying unit, A torsion control unit for varying the torsional load applied to the tension-torsion strap; And A first link connected to the torsion adjusting unit and the tensile load applying unit to apply a torsional load to the tension-torsion strap; Test device for tension-torsion strap for tilt rotor hub comprising a. The method of claim 1, At least one of the first measuring unit and the second measuring unit is a test device for a tension-torsion strap for a tilt rotor hub, characterized in that the load cell. The method of claim 1, The tensile load applying unit, A holder portion fixing both ends of the tension-torsion strap; And A tension control unit coupled to the holder along the axial direction of the tension-torsion strap, the tension control unit varying a magnitude of the tension applied to the tension-torsion strap by rotation; Test device for tension-torsion strap for tilt rotor hub comprising a. The method of claim 3, The holder of the tension-torsion strap for the tilt rotor hub, characterized in that the holder portion and the tension adjusting portion is screwed so that the holder portion can be linearly moved by the rotation of the tension adjusting portion. The method of claim 3, The first measuring unit is a test device for a tension-torsion strap for a tilt rotor hub, characterized in that provided on the end of the tension-torsion strap opposite the tension control unit. The method of claim 3, The tensile load applying unit further comprises a bearing unit for supporting the axial frictional force of the tension-torsion strap when the torsional load is applied to the test device of the tension-torsion strap for the tilt rotor hub. The method of claim 6, Apparatus for testing a tension-torsion strap for a tilt rotor hub, characterized in that the bearing portion is provided in the holder portion. The method of claim 6, Apparatus for testing a tension-torsion strap for a tilt rotor hub, characterized in that the bearing portion is a thrust bearing. The method of claim 3, And the torsional load applying unit is connected to the holder unit. delete The method of claim 1, The torsion adjusting unit, A torsion angle adjustment unit in which a first guide is formed to adjust the torsion angle of the tension-torsion strap; A second link having one end connected to the first link and the other end rotatably coupled to the torsion angle adjusting unit; And A second guide provided on the second link, the second guide fixing the second link as selectively coupled to the first guide; Test device for tension-torsion strap for tilt rotor hub comprising a. The method of claim 11, The second guide is a quick release pin (quick release pin) characterized in that the testing device of the tension-torsion strap for the tilt rotor hub. The method of claim 1, Wherein said first link and said second link are disposed in parallel. The method of claim 1, The second measuring unit is a test device for a tension-torsion strap for a tilt rotor hub, characterized in that provided between the first link and the second link.

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