Clamp suitable for testing compression mechanical property of large-size structural member

Abstract

The utility model provides a clamp suitable for testing the compression mechanical property of a large-size structural member, which comprises an electric loading cylinder, a self-calibration ball head, a ball head fine adjustment structure, a plurality of first flat plates, a plurality of first springs and a plurality of second flat plates which are distributed in an array, according to the utility model, a full-digital control and data acquisition system is adopted to control the whole device to move downwards, so that the second flat plate is contacted with the outer surface of a large-size structural member, and the bearing force is sequentially transmitted from the electric loading cylinder, the self-calibration ball head, the ball head fine adjustment structure, the first flat plate, the first spring and the second flat plate in consideration of the transmissibility of the force; compared with the traditional mode that a first flat plate is adopted for direct contact, the large-size flat plate structure adopts a plurality of second flat plates for direct contact with the outer surface of a large-size structure to adapt to the outer surfaces of different shapes, so that each area of the large-size flat plate structure can bear the same load at the same time under the pressure load, and the large-size flat plate structure is closer to the actual use working condition.

Description

TECHNICAL FIELD

[0001] The utility model relates to a test fixture for testing compression mechanical properties of large-size structural parts, belonging to the field of performance test fixtures. BACKGROUND

[0002] In typical large structures such as spacecraft fairing, ship keel cabin section, super high-rise building support system, it is necessary to accurately obtain the compression mechanical property data of large-size structural parts, which is beneficial to evaluate whether the expected load can be borne in actual application, test observable failure modes, detect whether manufacturing processes introduce defects affecting overall performance, etc.

[0003] Currently, in the field of safety evaluation of large-scale engineering structures, flat plate fixtures are mostly used to test test pieces, and the test data has significant size effect deviation, such as size effect coefficient of 0.3-0.6, which cannot meet the precision requirements of modern engineering structure fine design.

[0004] Specifically, the current "Standard Test Method for Compression Testing of Metallic Materials at Room Temperature" recommends a flat plate compression test method mainly for standard samples with a side length of not more than 300mm, and the rigid flat plate fixture used has a fundamental defect when dealing with large-size samples: when the sample size exceeds 800mm, affected by the material Poisson effect and structural flexibility, the sample center region will produce a 3-5mm out-of-plane displacement at 10% strain, resulting in a reduction of contact area by more than 40%, causing the local stress concentration coefficient to exceed the theoretical value by 2.8 times, which affects the accuracy of the test results on the one hand, and causes the local area to bear a large load and be damaged on the other hand. This testing limitation has caused a major technical accident of a certain type of launch vehicle fuel tank failing at 15% load in acceptance test.

[0005] Therefore, the utility model provides a test fixture for testing compression mechanical properties of large-size flat plate parts, which has the characteristics of convenient installation and high test accuracy, and can also realize pressure loading at different angles. UTILITY MODEL CONTENTS

[0006] Therefore, the utility model provides a test fixture for testing compression mechanical properties of large-size flat plate parts, which has the characteristics of convenient installation and high test accuracy, and can also realize pressure loading at different angles.

[0007] The utility model is implemented as follows:

[0008] A kind of test fixture suitable for the compression mechanical property of large size structural member, including electric loading cylinder, self-calibration ball head, ball head fine adjustment structure, first flat plate, first spring, second flat plate, the second flat plate quantity is several, array distribution, and each second flat plate is fixed in the bottom end surface of the first flat plate by several first springs, the output end of the electric loading cylinder is equipped with self-calibration ball head, and the self-calibration ball head is fixed in the top end surface of the first flat plate by ball head fine adjustment structure, to reach the mechanical force of electric loading cylinder output is transmitted to second flat plate via first flat plate.

[0009] As further improved, the utility model still includes portal frame, the electric loading cylinder is installed on the portal frame.

[0010] As further improved, the electric loading cylinder is electric cylinder.

[0011] As further improved, the utility model still includes force value sensor and displacement sensor, force value sensor and displacement sensor are installed in the electric loading cylinder.

[0012] As further improved, the utility model still includes controller, is installed in the one side of electric loading cylinder.

[0013] As further improved, the controller carries full digital control and data acquisition system.

[0014] As further improved, the model of the controller is EDC-3200.

[0015] As further improved, the ball head fine adjustment structure includes third flat plate, second spring and fourth flat plate, the third flat plate is connected between the fourth flat plate by several second springs, and the third flat plate is equipped with protrusion, the protrusion is rotatably connected with the self-calibration ball head, and the fourth flat plate is fixed in the top end surface of the first flat plate.

[0016] The utility model has the advantages that:

[0017] ①The utility model uses full digital control and data acquisition system to control the whole equipment to move down, so that the second flat plate contacts the outer surface of large size structural member, considering the force transmission, the bearing capacity is transmitted from electric loading cylinder, self-calibration ball head, ball head fine adjustment structure, first flat plate, first spring, second flat plate in turn, compared with traditional first flat plate direct contact, the utility model uses many second flat plates to directly contact the outer surface of large structure, adapts to different shapes of outer surface, so that each area of large size flat plate structural member can bear the same load under pressure load, and is closer to actual use condition.

[0018] The utility model discloses a plurality of second flat plates directly contact the outer surface of large structure, adapt to the outer surface of different shape, to realize that each area of large -size flat plate structural spare can bear the same load under pressure load, more close actual use working condition. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical scheme of the utility model embodiment, the following will be to the embodiment needed to use the drawing of simple introduction, it should be understood that the following drawings only shows some embodiments of the utility model, therefore should not be seen as the limitation of range, for ordinary skilled person in the art comes, under the premise of not paying creative labor, can also obtain other related drawings according to these drawings.

[0020] Figure 1 It is the principle schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member.

[0021] Figure 2 It is the partial structure three -dimensional schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member.

[0022] Figure 3 It is the ball head fine adjustment structure schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member.

[0023] Figure 4 It is the second flat plate structure schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member Figure 1 .

[0024] Figure 5 It is the second flat plate structure schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member Figure 2 .

[0025] Figure 6 It is the electric loading cylinder and gantry partial structure schematic diagram of the test fixture of the utility model embodiment suitable for the compression mechanical property of large -size structural member.

[0026] Fig. 10, self-calibration ball head 20, ball head fine adjustment structure 30, first flat plate 40, first spring 50, second flat plate 60, gantry 70, third flat plate 301, second spring 302, fourth flat plate 303, protrusion 304. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only to represent selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0028] In the description of the present application, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0029] Referring to Figures 1-6 The present embodiment provides a kind of concrete implementation mode about the test fixture suitable for large size structural piece compression mechanical property, including electric loading cylinder 10, self-calibration ball head 20, ball head fine adjustment structure 30, first flat plate 40, first spring 50, second flat plate 60, the second flat plate 60 quantity is several, array distribution is formed, and each second flat plate 60 is fixed in the bottom end surface of the first flat plate 40 by several first springs 50, the area of second flat plate 60 is less than the area of first flat plate 40, the output end of the electric loading cylinder 10 is installed with self-calibration ball head 20, and the self-calibration ball head 20 is fixed in the top end surface of the first flat plate 40 by ball head fine adjustment structure 30, to reach the mechanical force output by electric loading cylinder 10 is transmitted to second flat plate 60 via first flat plate 40.

[0030] The present application also includes a controller mounted on one side of the electric loading cylinder 10, and the controller is equipped with a full-digital control and data acquisition system.

[0031] The utility model discloses a whole equipment is controlled to move down by full digital control and data acquisition system, makes second flat plate 60 contact the outer surface of large size structural member, considers the force transmission, and the bearing capacity is transmitted in turn from electric loading cylinder 10, self-calibrating ball head 20, ball head fine adjustment structure 30, first flat plate 40, first spring 50, second flat plate 60, relative to the traditional first flat plate 40 direct contact, the utility model discloses a plurality of second flat plate 60 direct contact large structure outer surface, adapt to the outer surface of different shape, to realize that each area of large size flat plate structural member can bear the same load under pressure load, more close to actual use working condition.

[0032] In one embodiment, as shown in Figure 4 and Figure 5 The second flat plate 60 is arranged in an array, and the number of the second flat plate 60 is not limited, which can be 4 or 25. The number of the second flat plate 60 is determined according to the surface area of the large component, which is practical and flexible to apply. In addition, a through hole for mounting the first spring 50 is symmetrically arranged on each second flat plate 60, so that the second flat plate 60 can maintain balance in the initial state, and only when it contacts the outer surface of the large component in the loaded state, the state changes.

[0033] The reason why the loading effect of the second flat plate 60 is the same as that of the first flat plate 40 is that force can be synthesized. The first flat plate 40 drives the second flat plate 60 to load and synthesize. At this time, the loading effect of the second flat plate 60 is equivalent to that of the first flat plate 40. In addition, the loading of the second flat plate 60 can overcome the problem of local load deviation caused by the unloading of the large flat plate clamp. In the test process, the second flat plate 60 first contacts the structure, and as the load increases, the deformation of different areas of the structure is different, and the deformation of the second flat plate 60 is also different. However, due to the existence of the flat plate fine adjustment structure, each second flat plate 60 can still bear load at the same time. Because the size of the second flat plate 60 is small, the load on the loading area of the second flat plate 60 is relatively uniform, and the flat plate fine adjustment structure can make different areas still bear load at the same time, so that the second flat plate 60 does not occur.

[0034] In this embodiment, the ball head fine adjustment structure 30 includes a third flat plate 301, a second spring 302, and a fourth flat plate 303. The third flat plate 301 and the fourth flat plate 303 are connected by a plurality of second springs 302. The third flat plate 301 is provided with a protrusion 304, which is rotatably connected with the self-calibrating ball head 20. The fourth flat plate 303 is fixed to the top end surface of the first flat plate 40.

[0035] That is, the utility model discloses utilize ball head fine adjustment structure 30, first spring 50, satisfy some different angle pressure loading, for example, tilt 45 degrees loading, and not single vertical downward contact large -scale component, and flexibility increases, and practical scene increases.

[0036] In the embodiment, the utility model further includes portal frame 70, electric loading cylinder 10 is installed on portal frame 70.

[0037] Further, electric loading cylinder 10 is electric cylinder, electric cylinder is the modular product of the integration design of servo motor and screw rod, converts the rotary motion of servo motor into linear motion, simultaneously converts the best advantage of servo motor-precise speed control, accurate number of revolutions control, accurate torque control into-precise speed control, accurate position control, accurate thrust control, realizes the new product of high-precision linear motion series.

[0038] In the embodiment, the utility model further includes force value sensor and displacement sensor, force value sensor and displacement sensor are installed inside electric loading cylinder 10 to measure the displacement of clamp and the loading of electric loading cylinder 10.

[0039] In the embodiment, the model of controller is EDC-3200, adopts 32 bit high-speed ARM chip of Cortex_M4 as main control chip, has high-speed operation and data processing capacity, can accurately close loop control testing machine, the system can realize the three closed loop control of load, displacement, deformation of electronic universal testing machine, can smoothly switch among three control modes, can also carry out low cycle fatigue test, has the characteristics such as high control precision, strong adaptability, good stability.

[0040] The above only is preferred implementation way of the utility model and does not use to limit the utility model, for the skilled person in the art, the utility model can have various changes and changes. Any modification, equivalent replacement, improvement etc. that is made within the spirit and principle of the utility model should include in the protection scope of the utility model.

Claims

1. A test fixture for compressive mechanical property testing of large scale structural members, characterized by, The application relates to an electric loading cylinder (10), a self-calibrating ball head (20), a ball head fine adjustment structure (30), a first flat plate (40), a first spring (50), a plurality of second flat plates (60) arranged in an array and fixed to the bottom end surface of the first flat plate (40) through the first springs (50), wherein the output end of the electric loading cylinder (10) is provided with the self-calibrating ball head (20), the self-calibrating ball head (20) is fixed to the top end surface of the first flat plate (40) through the ball head fine adjustment structure (30), and mechanical force output by the electric loading cylinder (10) is transmitted to the second flat plates (60) through the first flat plate (40).

2. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 1, wherein The application further comprises a portal frame (70), and the electric loading cylinder (10) is arranged on the portal frame (70).

3. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 2, wherein The electric loading cylinder (10) is an electric cylinder.

4. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 1, wherein The application further comprises a force value sensor and a displacement sensor arranged in the electric loading cylinder (10).

5. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 1, wherein The application further comprises a controller arranged on one side of the electric loading cylinder (10).

6. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 5, wherein The controller is provided with a full-digital control and data acquisition system.

7. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 6, wherein The model of the controller is EDC-3200.

8. The test jig for testing compressive mechanical properties of large-sized structural members according to claim 6, wherein The ball head fine adjustment structure (30) comprises a third flat plate (301), a second spring (302) and a fourth flat plate (303), the third flat plate (301) and the fourth flat plate (303) are connected through the second springs (302), the third flat plate (301) is provided with a protrusion (304), the protrusion (304) is rotationally connected with the self-calibrating ball head (20), and the fourth flat plate (303) is fixed to the top end surface of the first flat plate (40).

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