Novel fatigue instability prevention tool

Abstract

The utility model belongs to the field of machinery, and relates to a novel fatigue instability prevention tool. A novel fatigue anti-instability tool comprises an upper base, a lower base, an upper anti-instability block and a lower anti-instability block, the upper base and the lower anti-instability block are identical in structure, and the anti-instability blocks are used for fixing splines. Screw holes used for fixing and clamping grooves or protrusions used for limiting the positions of the anti-instability blocks are arranged at the corresponding positions of the two bases respectively, and the two bases are fixed through bolt columns and nuts. The back face of the anti-instability block is a plane, the front face of the anti-instability block is an arc face, and the highest point of the arc face is located in the The anti-instability blocks are clamped in the clamping grooves of the base or embedded between the protrusions of the base. The fixture effectively solves the problem of fixture instability caused by complex installation, difficult centering and high cycle index during tension and compression fatigue tests, the whole fixture is simple in design and convenient to install, and the problem of instability of a sample during compression fatigue is effectively solved.

Description

Technical Field

[0001] The utility model belongs to the field of machinery and relates to a new type of fatigue anti-instability tooling. Background Art

[0002] In the process of traditional composite material testing, such as materials like fiberglass and pultruded plates, a series of fatigue test items such as tension-compression and compression-compression are often required. Due to the properties of the materials themselves and the lack of a good fixed material frame in the testing machine, the sample shows bending instability during the testing under pressure, resulting in the inability to complete the testing task. Therefore, many improvements have been made to the traditional testing methods. Summary of the Invention

[0003] In order to solve the problem that negative phenomena such as bending instability occur during the fatigue test pressing process of the specimen, resulting in the fracture of the specimen and the inability to achieve the test purpose, this application provides a fatigue anti-instability tooling with fast and accurate positioning.

[0004] A new type of fatigue anti-instability tooling includes two upper and lower bases with the same structure and two upper and lower anti-instability blocks with the same structure. The anti-instability blocks are used to fix the spline; corresponding positions on the two bases are respectively provided with screw holes for fixing and grooves or protrusions for limiting the position of the anti-instability blocks. The two bases are fixed by bolt columns and nuts; the back surface of the anti-instability block is a plane, and the front surface is an arc surface. The highest point of the arc surface is located at the center of the tooling; the anti-instability blocks are stuck in the grooves of the bases or embedded between the protrusions of the bases.

[0005] Further, a gasket is provided between the anti-instability block and the base. The gasket is stuck in the grooves of the base or embedded between the protrusions of the base. The gasket and the back surface of the anti-instability block are respectively provided with corresponding protrusions and grooves for limiting, and the gasket and the base are respectively provided with corresponding protrusions and grooves for limiting.

[0006] Further, the thickness of the gasket is less than the depth of the grooves or protrusions of the base.

[0007] Further, the corresponding protrusions and grooves between the gasket and the back surface of the anti-instability block are strip-shaped, and the corresponding protrusions and grooves between the gasket and the base are circular.

[0008] Further, the grooves or protrusions of the base are grooves formed with 4 protrusions in the middle, and there are two small protrusions in the grooves.

[0009] Further, the base is in an I shape, and screw holes for fixing are respectively provided at the four corners. The bolt column passes through the upper and lower bases and the bearing and is fixed with the nut. The bearing is a bearing with balls, which is used to connect and conduct with the bolt column, press the upper base above the specimen through the screw rod, and then lock the entire tooling with a locking nut.

[0010] Furthermore, it further includes a U-shaped positioning base. On both sides of the middle of the positioning base, there are protruding card slots for positioning the base, and in the centers of both ends of the positioning base, there are small slots for positioning the specimen.

[0011] Furthermore, the anti-instability block is replaceable and has different sizes.

[0012] During use, place the base on the positioning base, place a gasket and an anti-instability block of appropriate size on the base so that it can closely fit the specimen, and limit it with the card slot or protrusion. Install the same gasket and anti-instability block of appropriate size on another base. Wait until the sample (specimen) is placed between the anti-instability blocks, align its screw holes with the screw posts for installation, and clamp the sample into the anti-instability blocks. Put a bolt on the screw post and use a certain appropriate force to fix it so that the arc surface of the anti-instability block closely fits the sample. Use a caliper to measure until the four ends of the two bases are at the same level. Put the specimen with the anti-instability tooling on the machine for testing.

[0013] The utility model provides an anti-instability fixture for fatigue testing of fiber-reinforced composites, which includes a positioning base, a base assembly, four fixed screw posts connecting the upper and lower bases, upper and lower fixing gaskets and anti-instability blocks for fixing the specimen, and four locking nuts for locking the whole device. The names and structures of each component are as follows: (1) The positioning base has protruding card slot structures at both ends of the middle for positioning the base, and small slots at the centers of both ends for positioning the specimen. (2) The specimen. (3) The bearing for fixing. (4) The upper base has an I-shaped structure, with a protruding groove in the middle for fixing the anti-instability block, two small protrusions in the groove for fixing the gasket, and screw holes at the four ends for connecting the two ends of the base and installing it on both sides of the specimen. (5) The bolt for fixing the tooling. (6) The lower base includes two side bases, with an I-shaped structure, having a protruding groove in the middle for fixing the anti-instability block, two small protrusions in the groove for fixing the gasket, and screw holes at the four ends for connecting the two ends of the base and installing it on both sides of the specimen. (7) The gasket has two small holes in the middle for installation and fixation on the base. (8) The anti-instability block includes two anti-instability blocks, with a flat back and an arc-shaped front. The highest point of the arc surface is located at the center of the tooling and is used to closely fit the specimen. (9) The bolt post is placed in the bolt hole of the base for connection and fixing the tooling on both sides of the specimen.

[0014] Through the technical solution of the utility model, the problem of fixture instability caused by complex installation, difficult centering, and high cycle times during tensile-compression and compression-compression fatigue testing is effectively solved. The whole tooling design is simple and the installation is convenient, effectively solving the problem of specimen instability during compression-compression fatigue.

[0015] In order to ensure that the specimen does not bend and become unstable when subjected to a compressive force, a tooling is used for fixation, which can well ensure that the specimen is not affected by negative factors such as bending and shearing during the test. In order to quickly and accurately install the tooling at the center position of the specimen, a positioning base is used to quickly place the tooling on the specimen to ensure its centering. The use of convex grooves and gaskets can facilitate the replacement of the anti-instability blocks, ensuring that the tooling can closely fit the specimen regardless of the specimen's size. The product of this application can more quickly and accurately position the specimen and the tooling and install them in the middle of the specimen. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of the present utility model.

[0017] Figure 2 It is a schematic structural diagram of the gasket of the present utility model.

[0018] Figure 3 It is a schematic structural diagram of the base of the present utility model.

[0019] Figure 4 It is a schematic side view of the base of the present utility model.

[0020] Figure 5 It is an exploded view of the structure of the present utility model.

[0021] 1 Positioning base, 2 Spline, 3 Bearing, 4 Upper base, 5 Nut, 6 Lower base, 7 Gasket, 8 Anti-instability block, 9 Bolt column. Specific Embodiments

[0022] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments.

[0023] A new type of fatigue anti-instability tooling includes two upper and lower bases (4, 6) with the same structure and two upper and lower anti-instability blocks (8) with the same structure. The anti-instability blocks (8) fix the spline (2); corresponding positions of the two bases (4, 6) are respectively provided with screw holes for fixation and card slots or protrusions for defining the position of the anti-instability blocks (8). The two bases (4, 6) are fixed by bolt columns (9)(9) and nuts (5)(5); the back of the anti-instability block (8) is a plane, and the front is an arc surface, and the highest point of the arc surface is located at the center of the tooling; the anti-instability block (8) is stuck in the card slot of the base or embedded between the protrusions of the base.

[0024] A gasket (7) is provided between the anti-instability block (8) and the base. The gasket (7) is stuck in the card slot of the base or embedded between the protrusions of the base. The gasket (7) and the back of the anti-instability block (8) are respectively provided with corresponding protrusions and grooves for limiting by the gasket (7). The gasket (7) and the base are respectively provided with corresponding protrusions and grooves for limiting. The thickness of the gasket (7) is less than the depth of the card slot or the protrusion of the base. The corresponding protrusions and grooves on the back of the gasket (7) and the anti-instability block (8) are strip-shaped, and the corresponding protrusions and grooves between the gasket (7) and the base are circular.

[0025] The card slot or the protrusion of the base (4, 6) is a groove formed by 4 protrusions in the middle, and there are two small protrusions in the groove.

[0026] The base (4, 6) is in an I shape, and screw holes for fixation are respectively provided at the four corners. The bolt column (9) passes through the upper and lower bases and the bearing and is fixedly installed with the nut (5). The bearing is a bearing with balls, which is used to connect and conduct with the bolt column (9), press the upper base above the specimen through the screw rod, and then lock the entire tooling with the lock nut (5).

[0027] It further includes a U-shaped positioning base (1). On both sides in the middle of the positioning base (1), there are protruding card slots for positioning the lower base (6), and small slots for positioning are provided at the centers of both ends of the positioning base (1).

[0028] Among them, the anti-instability block (8) is replaceable and has different sizes.

[0029] During the installation process, the four fixed bolt columns (9) are fixed on the lower base and fixed with the fixed nut (5). Then, the lower base is placed on the positioning base (1). The positioning base (1) fixes the lower base (6) through the protruding sides. A centering gasket (7) is placed on the lower base (6). The lower base and the fixed gasket (7) are connected through the groove. The anti-instability block (8) is placed on the fixed gasket (7). The specimen (2 is placed) on the anti-instability block (8). There are bearings (3) with balls in the round holes at the four corners of the upper base (4), which are used to connect and conduct with the screw rod. The upper base (4) is pressed above the specimen (2) through the screw rod, and then the entire device is locked with the lock nut (5).

Claims

1. A new type of fatigue anti-instability tooling, comprising two upper and lower bases with the same structure and two upper and lower anti-instability blocks with the same structure, the anti-instability blocks are used to fix the splines; the characteristics are: The corresponding positions of the two bases are respectively provided with screw holes for fixing and slots or protrusions for limiting the position of the anti-instability block, and the two bases are fixed by bolt columns and nuts; the back of the anti-instability block is a flat surface, and the front is an arc surface, and the highest point of the arc surface is located at the center of the tooling; the anti-instability block is stuck in the slot of the base or embedded between the protrusions of the base.

2. The novel fatigue-proof instability tooling according to claim 1 is characterized in that: A gasket is provided between the anti-instability block and the base, the gasket is stuck in the slot of the base or embedded between the protrusions of the base, the gasket and the back of the anti-instability block are respectively provided with corresponding protrusions and grooves for limiting, and the gasket and the base are respectively provided with corresponding protrusions and grooves for limiting.

3. The novel fatigue-proof instability tooling according to claim 2 is characterized in that: The thickness of the gasket is smaller than the depth of the groove or protrusion of the base.

4. The novel fatigue-proof instability tooling according to claim 2 is characterized in that: The protrusions and grooves corresponding to each other on the back of the gasket and the anti-instability block are in the shape of long strips, and the protrusions and grooves corresponding to each other on the gasket and the base are in the shape of circles.

5. The novel fatigue-proof instability tooling according to any one of claims 1 to 4 is characterized in that: The card slot or protrusion of the base is a groove formed by four protrusions in the middle, and there are two small protrusions in the groove.

6. The novel fatigue-proof instability tooling according to claim 1 is characterized in that: The base is I-shaped, and screw holes for fixing are respectively provided at the four corners. The bolt column passes through the upper and lower bases and the bearings and nuts for fixing. The bearings are bearings with balls, which are used to connect and conduct with the bolt columns. The upper base is pressed onto the sample through the screw rod, and then the entire tooling is locked with a locking nut.

7. The novel fatigue-proof instability tooling according to claim 1 is characterized in that: It also includes a U-shaped positioning base, wherein the two sides in the middle of the positioning base are provided with protruding card grooves for positioning the substrate, and the centers of the two ends of the positioning base are provided with small grooves for positioning the sample.

8. The novel fatigue-proof instability tooling according to claim 1 is characterized in that: The anti-instability blocks are replaceable and have different sizes.

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