Metal material bending test device

Abstract

The invention discloses a metal material bending test device, relates to the technical field of metal material bending, and aims to solve the technical problem that a to-be-tested metal piece of an existing metal material bending test device is easy to deviate on a supporting point to influence a test result. By driving the two symmetrically-arranged limiting frames to get close to each other, the metal piece to be detected is corrected and limited, large-amplitude sliding of the metal piece in the horizontal direction is reduced, after correction, the spring and the adjusting piece are matched, opening and closing of the two limiting frames distributed in a V shape can be controlled, the limiting frames have a certain elastic allowance in the opening and closing direction, and the detection accuracy is improved. The sliding friction force between the clamp and the side face of the sample is converted into rolling friction force by matching with the balls on the inner side walls of the limiting frames, and the two limiting frames are distributed in a V shape, so that the two ends of the sample can quickly leave the limiting frames after rising upwards, the two ends of the sample are prevented from rising naturally in the bending process of the sample, and the test precision is improved.

Description

Technical Field

[0001] This invention relates to the field of metal material bending technology, and more specifically, to a metal material bending test apparatus. Background Technology

[0002] Before metal products such as sheets, bars, and profiles are used in engineering applications, their bending plastic deformation capacity and mechanical properties need to be evaluated through bending tests. Currently, a three-point bending test machine is commonly used for this test. The principle is as follows: the two ends of the specimen are placed freely on two parallel support rollers to form a fixed span; then, a concentrated load is applied downward through a pressure head directly above the midpoint of the two support points of the specimen; as the load increases, the specimen gradually bends between the two support points. When the tensile stress on the bottom surface of the middle reaches the material limit, the specimen will usually break near the midpoint of the span or reach the specified bending angle. In order to reduce the large additional axial stress or bending moment generated by friction constraints at the support points, the support points are generally set as rotatable smooth cylindrical rollers, which are simple in structure and convenient to operate.

[0003] Existing metal material bending test devices, such as the three-point bending test method, have the following disadvantages during use: 1. Since the support surface is usually a smooth cylindrical roller, when there is a slight deviation in the placement of the sample, it is easy to slip along its horizontal direction. Excessive displacement will greatly change the actual path of the applied force, greatly increasing the test error; 2. Even if lateral clamps are applied to both ends of the sample for correction and limitation, the sliding friction between the clamps and the side of the sample will form an additional lateral constraint, directly hindering the natural extension and contraction of the sample during the bending process, resulting in distortion of the measured load, displacement and the mechanical property parameters calculated accordingly, which also seriously reduces the detection accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a bending test device for metal materials to overcome the above-mentioned shortcomings in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: including a support frame; The three-point bending test specimen is set on the inner side wall of the support frame and includes two sets of symmetrically arranged support members and a pressing component located directly above the midpoint between the two sets of support members. The limiting components are arranged in two sets and symmetrically at both ends of the three-point bending test piece. Each set includes two symmetrically arranged clamps. The clamps are hinged to the opposite faces of the limiting frames. The two limiting frames are distributed in a "V" shape and are symmetrically arranged. The two limiting frames can be driven by a self-locking drive component through a bidirectional screw component to move closer to or further away from each other. A spring is detachably connected between the clamp and the limiting frame, and is located above the hinge. An adjusting element is installed through the outer wall of the clamp and can be used with a spring to adjust the opening and closing angle of the two limiting frames that are distributed in a "V" shape.

[0006] As a further description of the above technical solution: the support includes a first frame, the outer side wall of the first frame is provided with a first circular hole, the inner side wall of the first circular hole is equipped with a bearing and is rotatably connected to a support roller through the bearing.

[0007] As a further description of the above technical solution: the clamp includes a second frame, the outer side wall of the second frame has a second circular hole that can cooperate with the adjusting component, and a scale ring is installed on the outer side wall of the second frame, the scale ring being arranged around the second circular hole.

[0008] As a further description of the above technical solution: the limiting frame includes a frame body, and a number of ball bearings are equidistantly connected to the outer wall of the frame body along its edge line, and a third frame body is installed on the inner wall of the frame body.

[0009] As a further description of the above technical solution: the adjusting component includes a screw that can pass through the second circular hole and the third frame, one end of the screw is fixed with a limiting piece, the other end of the screw is threaded with a nut, and the outer wall of the nut is provided with an indicator tip that can cooperate with the scale ring.

[0010] As a further description of the above technical solution: a handle is installed on the outer wall of the nut.

[0011] As a further description of the above technical solution: the bidirectional screw component includes a limiting shell, and a bidirectional threaded screw is rotatably connected to the inner side wall of the limiting shell. The two ends of the bidirectional threaded screw are respectively provided with a left-hand thread and a right-hand thread, and the left-hand thread end and the right-hand thread end are respectively threadedly connected to a screw sleeve.

[0012] As a further description of the above technical solution: the self-locking drive component includes a worm gear fixed to the end of a bidirectional threaded screw, a worm is meshed with the outer wall of the worm gear, the worm is rotatably connected to the outer wall of the support frame, and a handwheel is installed on the top of the worm.

[0013] In the above technical solution, the present invention provides the following beneficial effects: This invention can drive two symmetrically arranged limiting frames to move closer to each other, correcting and limiting the metal part to be tested, reducing its large-scale slippage in the horizontal direction. After correction, in conjunction with springs and adjusting components, it can not only control the opening and closing of the two "V"-shaped limiting frames, but also give them a certain elastic margin in the opening and closing direction, reducing the resistance to the lateral deformation of the sample under pressure. In conjunction with the ball bearings on the inner sidewall of the limiting frames, the sliding friction between the fixture and the side of the sample is converted into rolling friction. Furthermore, because the two limiting frames are "V"-shaped, the two ends of the sample can quickly leave the limiting frames after they rise, reducing the resistance to the natural upward movement of the two ends of the sample during bending, improving the test accuracy, and solving the problem that the metal part under test is prone to shifting at the support point in existing metal material bending test devices, affecting the test results. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0015] Figure 1 This is a schematic diagram of the exploded structure provided in an embodiment of the present invention; Figure 2 A schematic diagram of the connection structure of the limiting member, the bidirectional lead screw, and the self-locking drive member provided in an embodiment of the present invention; Figure 3 for Figure 2 Schematic diagram of the structure at point A; Figure 4 This is a side view of the limiting member, bidirectional lead screw, and self-locking drive member provided in the embodiments of the present invention. Figure 5 An exploded structural diagram of the limiting member, bidirectional lead screw, and self-locking drive member provided in the embodiments of the present invention; Figure 6 This is a schematic diagram of the structure of the adjusting member provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of the support member provided in an embodiment of the present invention; Figure 8 A front view of the overall structure provided for an embodiment of the present invention; Figure 9 A side view provided for an embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures: 1. Support frame; 2. Three-point bending test specimen; 3. Limiting component; 4. Two-way lead screw component; 5. Self-locking drive component; 201. Downward pressure assembly; 202. Support component; 2021, First frame; 2022, First circular hole; 2023, Bearing; 2024, Support roller; 301. Clamp; 302. Limiting frame; 303. Spring; 304. Adjusting component; 3011, Second frame; 3012, Second circular hole; 3013, Scale ring; 3021, frame; 3022, ball bearing; 3023, third frame; 3041, Screw; 3042, Limiting plate; 3043, Nut; 3044, Indicator tip; 401. Limiting housing; 402. Double-ended threaded screw; 403. Screw sleeve; 501. Worm gear; 502. Worm; 503. Handwheel. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0018] Please see Figures 1-9 The present invention provides a technical solution including a support frame 1; Three-point bending test specimen 2 is set on the inner side wall of support frame 1, including two sets of support members 202 symmetrically arranged and a pressing component 201 located directly above the midpoint between the two sets of support members 202; Two sets of support members 202 are symmetrically arranged to support both ends of the specimen; the pressing component 201 is located directly above the midpoint of the two sets of support members 202 and is used to apply a vertically downward force to the specimen. The pressure assembly 201 adopts an existing product from the existing three-point bending test specimen 2; In another embodiment of the present invention, preferably, the support member 202 includes a first frame 2021, a first circular hole 2022 is provided on the outer side wall of the first frame 2021, a bearing 2023 is installed on the inner side wall of the first circular hole 2022 and a support roller 2024 is rotatably connected through the bearing 2023, so that when the sample is bent and deformed, there is rolling friction between it and the support point, which reduces the influence of frictional resistance on the test.

[0019] The limiting component 3 has two sets and is symmetrically arranged at both ends of the three-point bending test piece 2. Each set includes two symmetrically arranged clamps 301. The clamps 301 are hinged to the opposite faces of the limiting frame 302. The two limiting frames 302 are distributed in a "V" shape and are symmetrically arranged. The two limiting frames 302 can be driven by the self-locking drive component 5 through the bidirectional screw component 4 to move closer to each other / away from each other. There are two sets of limiting components 3, which are symmetrically arranged on the outer sides of both ends of the three-point bending test specimen 2, and are used to correct and elastically limit the specimen. Each set of limiting components 3 includes two symmetrically arranged clamps 301, a limiting frame 302 hinged to the clamps 301, a spring 303 that provides elastic margin, and an adjusting component 304. The two limiting frames 302 are distributed in a "V" shape, and their opening and closing can be controlled by the cooperation of the bidirectional screw component 4 and the self-locking drive component 5. In another embodiment of the present invention, the clamp 301 includes a second frame 3011. The outer side wall of the second frame 3011 has a second circular hole 3012 that can cooperate with the adjusting member 304. A scale ring 3013 is installed on the outer side wall of the second frame 3011. The scale ring 3013 is arranged around the second circular hole 3012 and is used to accurately indicate the adjustment angle.

[0020] In another embodiment of the present invention, the limiting frame 302 includes a frame 3021, a plurality of ball bearings 3022 are rotatably connected to the outer side wall of the frame 3021 at equal intervals along its edge, and a third frame 3023 is installed on the inner side wall of the frame 3021.

[0021] Spring 303 is detachably connected between clamp 301 and limit frame 302, and is located above the hinge; The adjusting component 304 is installed through the outer wall of the clamp 301 and can be used with the spring 303 to adjust the opening and closing angle of the two “V”-shaped limiting frames 302, so that the two “V”-shaped limiting frames 302 have elastic buffering capacity when clamping the sample, so that the sample can be smoothly deformed laterally during the test.

[0022] In another embodiment of the present invention, the adjusting member 304 includes a screw 3041 that can pass through the second circular hole 3012 and the third frame 3023. One end of the screw 3041 is fixed with a limiting piece 3042, and the other end of the screw 3041 is threadedly connected with a nut 3043. The outer wall of the nut 3043 is provided with an indicator tip 3044 that can cooperate with the scale ring 3013. The adjusting component 304 is installed through the outer wall of the clamp 301. It can not only be used to adjust the opening and closing angle of the two "V" shaped limit frames 302 in conjunction with the spring 303 to provide different clamping forces, but also to quickly install or remove and replace the spring 303. When it is necessary to remove the spring 303, unscrew the nut 3043 and pull out the screw 3041 to remove the spring 303.

[0023] The outer wall of the nut 3043 is provided with an indicator tip 3044, which can be used with the scale ring 3013 to achieve fine angle adjustment; In another embodiment of the present invention, a handle is installed on the outer side wall of the nut 3043 to facilitate turning the nut 3043.

[0024] In another embodiment of the present invention, the bidirectional screw component 4 includes a limiting shell 401, and a bidirectional threaded screw 402 is rotatably connected to the inner wall of the limiting shell 401. The two ends of the bidirectional threaded screw 402 are respectively provided with a left-hand thread and a right-hand thread, and the left-hand thread end and the right-hand thread end are respectively threadedly connected to the screw sleeve 403. When the bidirectional threaded screw 402 rotates, it can drive the two screw sleeves 403 to move synchronously towards or away from each other.

[0025] In another embodiment of the present invention, the self-locking drive component 5 includes a worm gear 501 fixed to the end of the bidirectional threaded screw 402, a worm 502 meshing with the outer wall of the worm gear 501, the worm 502 being rotatably connected to the outer wall of the support frame 1, and a handwheel 503 being installed on the top of the worm 502.

[0026] By operating the handwheel 503 to rotate the worm gear 502, the worm wheel 501 and the double-ended threaded screw 402 can be rotated. Due to the inherent self-locking characteristics of the worm wheel 501 and worm gear 502 mechanism, the position of the clamp 301 can be locked when the drive stops, preventing large displacement and loosening during the test.

[0027] Working principle: This embodiment provides a metal material bending test device. Before the test begins, by rotating the handwheel 503, the clamps 301 are driven to move closer to each other synchronously via the worm gear 502, worm wheel 501, and bidirectional lead screw 4. Since the two symmetrically arranged clamps 301 are hinged to the opposite surfaces with limit frames 302, and the two limit frames 302 are distributed in a "V" shape, they can be corrected and limited with a certain elastic margin from both sides of the sample, effectively preventing large-scale horizontal slippage in the subsequent bending test.

[0028] The limiting frames 302, which are arranged in a "V" shape, are supported by the upper spring 303. It should be noted that the length of the selected spring 303 needs to be ensured. In the initial state, the two limiting frames 302 are arranged in a "V" shape with the upper one being larger than the lower one, and their constraint on the sample is elastic rather than rigidly locked. When the sample undergoes lateral expansion due to the Poisson effect during bending, the spring 303 allows the limiting frames 302 to make small displacements, thereby greatly reducing the resistance to the lateral deformation of the sample. The ball bearings 3022 provided on the surface of the limiting frame 302 convert the sliding friction with the side of the sample into rolling friction, further reducing the additional friction introduced by the constraint device; The "V"-shaped opening design allows the two ends of the sample to naturally tilt upwards when bent, smoothly disengaging from the limiting frame 302. This enables the sample to quickly detach from contact with the limiting frame 302, reducing the duration of friction between the sample and the limiting frame 302. Meanwhile, the limiting frame 302 is designed as a frame, that is, it is symmetrically limited at two points on both sides of the sample end, which stabilizes the limiting and reduces the contact area with both sides of the sample, reduces friction, and reduces the resistance to the natural upward movement of both ends of the sample during bending, thus improving the test accuracy. The initial angle of the limit frame 302 can be adjusted relatively precisely through the adjusting component 304 and the scale ring 3013; preferably, the two sets of bidirectional threaded screws 402 of the two sets of bidirectional screw components 4 can also be connected through a transmission component. The transmission component can be a chain-sprocket type or a belt-pulley type, and is centrally driven by a set of self-locking drive components 5. The handwheel 503 can also be replaced with an existing product motor that is connected to an external power source and an external switch.

[0029] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A bending test apparatus for metallic materials, characterized in that, Including support frame (1); The three-point bending test piece (2) is set on the inner side wall of the support frame (1), including two sets of support members (202) arranged symmetrically and a pressing component (201) located directly above the midpoint between the two sets of support members (202). The limiting component (3) has two sets and is symmetrically arranged at both ends of the three-point bending test piece (2). Each set includes two symmetrically arranged clamps (301). The clamps (301) are hinged to the opposite faces of the limiting frame (302). The two limiting frames (302) are distributed in a "V" shape and are symmetrically arranged. The two limiting frames (302) can be driven by the self-locking drive component (5) through the bidirectional screw component (4) to move closer to each other / away from each other. Spring (303) is detachably connected between clamp (301) and limit frame (302) and is located above the hinge; An adjusting element (304) is provided through the outer wall of the clamp (301) and can be used with a spring (303) to adjust the opening and closing angle of the two "V"-shaped limiting frames (302).

2. The bending test apparatus for metallic materials according to claim 1, characterized in that, The support member (202) includes a first frame (2021), the outer side wall of the first frame (2021) is provided with a first circular hole (2022), the inner side wall of the first circular hole (2022) is equipped with a bearing (2023) and a support roller (2024) is rotatably connected through the bearing (2023).

3. The bending test apparatus for metallic materials according to claim 2, characterized in that, The clamp (301) includes a second frame (3011), the outer wall of the second frame (3011) is provided with a second round hole (3012) that can cooperate with the adjusting member (304), and a scale ring (3013) is installed on the outer wall of the second frame (3011), the scale ring (3013) is arranged around the second round hole (3012).

4. The bending test apparatus for metallic materials according to claim 3, characterized in that, The limiting frame (302) includes a frame (3021), and a number of ball bearings (3022) are rotatably connected to the outer side wall of the frame (3021) at equal intervals along its edge. A third frame (3023) is installed on the inner side wall of the frame (3021).

5. The bending test apparatus for metallic materials according to claim 4, characterized in that, The adjusting component (304) includes a screw (3041) that can pass through the second circular hole (3012) and the third frame (3023). One end of the screw (3041) is fixed with a limiting piece (3042), and the other end of the screw (3041) is threaded with a nut (3043). The outer wall of the nut (3043) is provided with an indicator tip (3044) that can cooperate with the scale ring (3013).

6. The bending test apparatus for metallic materials according to claim 5, characterized in that, A handle is installed on the outer wall of the nut (3043).

7. The bending test apparatus for metallic materials according to claim 6, characterized in that, The bidirectional screw component (4) includes a limiting shell (401), and a bidirectional threaded screw (402) is rotatably connected to the inner side wall of the limiting shell (401). The two ends of the bidirectional threaded screw (402) are respectively provided with a left-hand thread and a right-hand thread, and the left-hand thread end and the right-hand thread end are respectively threadedly connected to a screw sleeve (403).

8. The bending test apparatus for metallic materials according to claim 7, characterized in that, The self-locking drive (5) includes a worm wheel (501) fixed to the end of a bidirectional threaded screw (402), a worm (502) meshing with the outer wall of the worm wheel (501), the worm (502) being rotatably connected to the outer wall of the support frame (1), and a handwheel (503) being installed on the top of the worm (502).

Images