Positioning clamp for tensile test of polyurethane mixture

Abstract

The utility model discloses a positioning clamp for a tensile test of a polyurethane mixture, and relates to the technical field of performance detection of the polyurethane mixture. The device comprises a supporting piece and an adjusting sleeve, the supporting piece comprises a bearing sleeve and a mounting sleeve coaxially fixed to one end of the bearing sleeve. A plurality of accommodating notches are uniformly formed in one port, far away from the bearing sleeve, of the mounting sleeve; rotating shafts are arranged in the accommodating notches; the plurality of rotating shafts are radially and rotationally connected with positioning plates; conical blocks are fixed to the side faces, away from the central axis of the bearing sleeve, of the multiple positioning plates; one surface, far away from the positioning plate, of each conical block is an inclined surface; the adjusting sleeve is in threaded fit with the periphery of the mounting sleeve; one port, away from the bearing sleeve, of the adjusting sleeve abuts against the inclined faces of the conical blocks. According to the utility model, not only is the clamping effect on the polyurethane mixture test piece effectively improved, but also the tensile test effect of the polyurethane mixture test piece is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of polyurethane mixture performance detection, in particular to a positioning fixture used for polyurethane mixture tensile testing. Background Art

[0002] Polyurethane is a chemical product made by mixing polyols and isocyanates in a certain ratio. It has excellent mechanical strength, wear resistance and elasticity, and can replace asphalt in the mixture. Because polyurethane mixture has good mechanical properties and its splitting strength is more than three times that of asphalt, its rheological deformation at high temperature is much smaller than that of asphalt mixture. It has good resistance to high-temperature deformation and fatigue cracking, and is an excellent road engineering paving material.

[0003] During the production and use of polyurethane mixtures, various performance tests are usually required to understand their performance, such as density, crack resistance, compression resistance, tensile strength, etc. During the tensile test of polyurethane mixtures, it is necessary to fix the polyurethane mixture specimen on the tensile tester through a positioning fixture. The traditional positioning fixture is usually as shown in the attached manual. Figure 1 As shown, the polyurethane mixture specimen is positioned and clamped by placing the end of the polyurethane mixture specimen between two clamping plates (01) and controlling the two clamping plates (01) to approach each other. Although this positioning fixture is relatively simple, it will not have sufficient clamping force on the polyurethane mixture specimen during use, causing the polyurethane mixture specimen to fall off the positioning fixture during the tensile test, affecting the tensile test effect of the polyurethane mixture specimen. Therefore, it is urgent to study a positioning fixture for polyurethane mixture tensile testing to solve the above problems. Utility Model Content

[0004] The utility model provides a positioning fixture for a tensile test of a polyurethane mixture, and its purpose is to solve the technical problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] The utility model is a positioning fixture for tensile testing of polyurethane mixtures, comprising a support member and an adjusting sleeve; the support member comprises a vertically arranged bearing sleeve and a mounting sleeve coaxially fixed to one end of the bearing sleeve; a plurality of accommodating notches are evenly distributed on a port of the mounting sleeve away from the bearing sleeve; a plurality of rotating shafts are provided in the plurality of accommodating notches, and the two ends of each of the rotating shafts are respectively fixedly inserted into the opposite side surfaces of the corresponding accommodating notches; a plurality of rotating shafts are radially rotatably connected with positioning plates; a plurality of positioning plates are horizontally fixed with a plurality of convex strips on a side surface close to the central axis of the bearing sleeve; a plurality of positioning plates are fixed with a conical block on a side surface away from the central axis of the bearing sleeve; a plurality of surfaces of the conical blocks away from the positioning plate are all inclined surfaces; the adjusting sleeve is threadedly fitted on the outer periphery of the mounting sleeve; a port of the adjusting sleeve away from the bearing sleeve conflicts with the inclined surfaces of a plurality of conical blocks.

[0007] As an optimal technical solution of the present invention, a pair of coaxially arranged side sleeves are radially fixed to the circumferential side wall of the bearing sleeve; bolts are threadedly fitted in the two side sleeves; and the adjacent ends of the two bolts can extend to the inner side of the bearing sleeve.

[0008] As a preferred technical solution of the present invention, the inner diameter of the bearing sleeve is larger than the inner diameter of the mounting sleeve; the outer diameter of the bearing sleeve is larger than the outer diameter of the adjustment sleeve; a step structure is provided between the end of the bearing sleeve close to the positioning plate and the end of the mounting sleeve away from the positioning plate; the end of the adjustment sleeve close to the bearing sleeve can conflict with a surface of the step structure close to the positioning plate.

[0009] As a preferred technical solution of the present invention, a carrying plate is horizontally placed on a surface of the step structure away from the positioning plate; and an adhesive layer is provided on a surface of the carrying plate close to the positioning plate.

[0010] As a preferred technical solution of the present invention, a port of the adjustment sleeve away from the bearing sleeve is an arc-shaped structure.

[0011] The utility model has the following beneficial effects:

[0012] The utility model fixes the bearing sleeve vertically on the tension output component of the tensile tester, slides the end of the polyurethane mixture specimen into the installation sleeve, and then rotates the adjusting sleeve to the side away from the bearing sleeve, so that the adjusting sleeve pushes the multiple conical blocks to approach each other, and the conical blocks drive the multiple positioning plates to rotate in the direction of the central axis of the installation sleeve, so that the convex strips tightly bite the end of the polyurethane mixture specimen, thereby effectively improving the clamping force of the polyurethane mixture specimen, avoiding the problem of the polyurethane mixture specimen falling off the positioning fixture during the rope pulling test, and effectively ensuring the tensile test effect of the polyurethane mixture specimen.

[0013] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 The figure is a schematic structural diagram of a positioning fixture used for tensile testing of polyurethane mixtures in the prior art.

[0016] Figure 2 The utility model is a structural schematic diagram of a positioning fixture used for tensile testing of polyurethane mixtures.

[0017] Figure 3 for Figure 2 The main view of the structure.

[0018] Figure 4 This is a schematic structural diagram of the support member of the present invention.

[0019] Figure 5 It is a cross-sectional view of the structure of the connection between the bearing sleeve and the installation sleeve of the utility model.

[0020] Figure 6 It is a structural schematic diagram of the positioning plate of the present utility model.

[0021] Figure 7 The utility model is a diagram showing the use state of a positioning fixture for a tensile test of a polyurethane mixture arranged on a tensile tester.

[0022] Figure 8 It is a structural schematic diagram of a tensile testing instrument in the prior art.

[0023] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0024] 01- splint, 02- brake column, 03- blind hole, 1- support, 2- adjustment sleeve, 3- positioning plate, 4- rotating shaft, 5- bearing plate, 101- bearing sleeve, 102- mounting sleeve, 103- receiving notch, 104- side sleeve, 105- bolt, 106- step structure, 301- convex strip, 302- conical block, 501- adhesive layer. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] Example 1:

[0027] See also Figure 2-6 As shown, the utility model is a positioning fixture for tensile testing of polyurethane mixtures, including a support member 1 and an adjusting sleeve 2; the support member 1 includes a vertically arranged bearing sleeve 101 and a mounting sleeve 102 coaxially welded to one end of the bearing sleeve 101; a pair of coaxially arranged side sleeves 104 are radially welded to the circumferential side walls of the bearing sleeve 101; both side sleeves 104 are threaded with conventional bolts 105 in this field; the ends of the two bolts 105 close to each other can extend to the inner side of the bearing sleeve 101; a plurality of rectangular accommodating notches 103 are evenly distributed on the end of the mounting sleeve 102 away from the bearing sleeve 101; a plurality of accommodating notches 103 are each provided with a rotating shaft 4, and the two ends of each rotating shaft 4 are respectively fixedly inserted on the opposite sides of the corresponding accommodating notch 103; a plurality of rotating shafts 4 are radially rotatably connected with a positioning plate 3, that is, the rotating shaft 4 is inserted and arranged at an edge of the positioning plate 3 close to the bearing sleeve 101, and the rotating shaft 4 is arranged parallel to the edge of the positioning plate 3; multiple positioning plates 3 are welded with multiple convex strips 301 horizontally on one side close to the central axis of the bearing sleeve 101; multiple positioning plates 3 are welded with conical blocks 302 with a right-angled triangle structure on one side away from the central axis of the bearing sleeve 101; multiple conical blocks 302 are all welded with an inclined surface on one surface away from the positioning plate 3, that is, the inclined surface is the hypotenuse of the right-angled triangle structure, and the right-angled end of the conical block 302 is arranged at an edge of the positioning plate 3 away from the bearing sleeve 101; the adjusting sleeve 2 is threadedly fitted on the outer periphery of the mounting sleeve 102; the end of the adjusting sleeve 2 away from the bearing sleeve 101 conflicts with the inclined surfaces of multiple conical blocks 302; the end of the adjusting sleeve 2 away from the bearing sleeve 101 is an arc-shaped structure, which can ensure the conflict effect between the end of the adjusting sleeve 2 away from the bearing sleeve 101 and the inclined surface of the conical block 302, thereby reducing the wear of the end of the adjusting sleeve 2 away from the bearing sleeve 101. When in use, Figure 7-8As shown, the positioning fixture is applied to a tensile tester in the prior art. A pair of coaxially arranged blind holes 03 are radially opened on the circumferential side wall of the brake column 02 for transmitting tension in the tensile tester in the prior art. By sliding the bearing sleeve 101 on the outer circumference of the brake column 02 and slidingly inserting the two bolts 105 into the two blind holes 03 respectively, the support member 1 is fixed to the tensile tester, and then the end of the polyurethane mixture specimen is slidably inserted into the mounting sleeve 102. Then, by rotating the adjustment sleeve 2 to the side away from the bearing sleeve 101, the adjustment sleeve 2 pushes the multiple conical blocks 302 closer to each other, and the conical blocks 302 drive the multiple positioning plates 3 to rotate toward the central axis of the mounting sleeve 102, so that the convex strips 301 tightly bite the ends of the polyurethane mixture specimen, thereby effectively improving the clamping force of the polyurethane mixture specimen, avoiding the problem of the polyurethane mixture specimen falling off the positioning fixture during the rope pulling test, and effectively ensuring the tensile test effect of the polyurethane mixture specimen.

[0028] Example 2:

[0029] Based on Example 1 Figure 3 and Figure 5As shown, the inner diameter of the bearing sleeve 101 is larger than the inner diameter of the mounting sleeve 102; the outer diameter of the bearing sleeve 101 is larger than the outer diameter of the adjusting sleeve 2; a step structure 106 is integrally formed between the lower end of the bearing sleeve 101 and the upper end of the mounting sleeve 102; the end of the adjusting sleeve 2 close to the bearing sleeve 101 can conflict with a surface of the step structure 106 close to the positioning plate 3; a bearing plate 5 is horizontally placed on a surface of the step structure 106 away from the positioning plate 3; the outer diameter of the bearing plate 5 is slightly smaller than the inner diameter of the bearing sleeve 101, and the outer diameter of the bearing plate 5 is larger than the outer diameter of the mounting sleeve 102; a surface of the bearing plate 5 close to the positioning plate 3 is provided with a conventional adhesive layer 501 in this field; the adhesive layer 501 is a filled epoxy resin adhesive layer or a 502 adhesive layer, and other types of resin adhesives can also be used. It can be found through experiments that these adhesives can firmly bond the polyurethane mixture specimen and the bearing plate 5 at room temperature and will not affect the normal progress of the tensile test. During use, first pass the end of the polyurethane mixture specimen through the mounting sleeve 102 and the bearing sleeve 101 in turn, and then connect the end face of the polyurethane mixture specimen to the bearing plate 5 through the adhesive layer 501 (the thickness of the adhesive layer 501 can be about 3-5 mm). After the adhesive layer 501 is completely cured and firmly bonded, the bearing plate 5 is installed into the bearing sleeve 101 and placed on a surface of the step structure 106 away from the positioning plate 3. Then, the bearing sleeve 101 is slidably mounted on the outer periphery of the brake column 02, and the two bolts 105 are slidably inserted into the two blind holes 03 respectively. By designing the adhesive layer 501, the clamping force of the polyurethane mixture specimen can be further improved. After the test is completed, the polyurethane mixture specimen is broken, and the two positioning fixtures can be removed from the tensile tester respectively, and then the adhesive layer 501 on the surface of the carrier plate 5 can be removed by heating (for example, using a temperature of 200-300 degrees Celsius can carbonize the adhesive layer 501 and lose its stickiness, and the adhesive layer 501 can be removed). The cleaned carrier plate 5 can be reused next time.

[0030] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. The preferred embodiments do not describe all details in detail, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A positioning fixture for tensile testing of polyurethane mixtures, characterized in that: It comprises a support member (1) and an adjustment sleeve (2); The support member (1) comprises a vertically arranged bearing sleeve (101) and a mounting sleeve (102) coaxially fixed on one end of the bearing sleeve (101); a plurality of accommodating notches (103) are evenly distributed on one end of the mounting sleeve (102) away from the bearing sleeve (101); a rotating shaft (4) is arranged in each of the plurality of accommodating notches (103), and the two ends of each of the rotating shafts (4) are respectively fixedly plugged into the opposite side surfaces of the corresponding accommodating notch (103); a positioning plate (3) is radially rotatably connected to each of the plurality of rotating shafts (4). ; A plurality of convex strips (301) are horizontally fixed to the side surfaces of the plurality of positioning plates (3) close to the central axis of the bearing sleeve (101); a conical block (302) is fixed to the side surfaces of the plurality of positioning plates (3) away from the central axis of the bearing sleeve (101); a surface of the plurality of conical blocks (302) away from the positioning plates (3) is an inclined surface; the adjusting sleeve (2) is threadedly engaged with the outer periphery of the mounting sleeve (102); a port of the adjusting sleeve (2) away from the bearing sleeve (101) is in conflict with the inclined surfaces of the plurality of conical blocks (302).

2. The positioning fixture for tensile testing of polyurethane mixture according to claim 1, characterized in that: A pair of coaxially arranged side sleeves (104) are radially fixed to the circumferential side wall of the bearing sleeve (101); bolts (105) are threadedly fitted inside the two side sleeves (104); and the adjacent ends of the two bolts (105) can extend to the inner side of the bearing sleeve (101).

3. The positioning fixture for tensile testing of polyurethane mixture according to claim 1 or 2, characterized in that: The inner diameter of the bearing sleeve (101) is greater than the inner diameter of the mounting sleeve (102); the outer diameter of the bearing sleeve (101) is greater than the outer diameter of the adjustment sleeve (2); a step structure (106) is provided between an end of the bearing sleeve (101) close to the positioning plate (3) and an end of the mounting sleeve (102) away from the positioning plate (3); an end of the adjustment sleeve (2) close to the bearing sleeve (101) can abut against a surface of the step structure (106) close to the positioning plate (3).

4. The positioning fixture for tensile testing of polyurethane mixture according to claim 3, characterized in that: A carrying plate (5) is horizontally placed on a surface of the step structure (106) away from the positioning plate (3); and an adhesive layer (501) is provided on a surface of the carrying plate (5) close to the positioning plate (3).

5. The positioning fixture for tensile testing of polyurethane mixture according to claim 4, characterized in that: A port of the adjustment sleeve (2) away from the bearing sleeve (101) is an arc-shaped structure.

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