A universal testing machine for tension and shear testing

Abstract

The present invention relates to the technical field of testing devices, and discloses a universal testing machine for tension-shear testing, comprising: a bracket; a lower chuck fixed in the middle of the bracket; a tension disk arranged at a certain distance above the lower chuck; a tension hydraulic cylinder arranged at the top of the bracket and connected to the tension disk; an upper chuck fixed below the tension disk; a shear assembly arranged between the lower chuck and the upper chuck, wherein a plurality of screws are connected around the shear assembly; compared with the prior art, the present invention realizes a more comprehensive and accurate mechanical property evaluation of a material sample.

Description

Technical Field

[0001] The invention relates to the technical field of testing devices, in particular to a universal testing machine for tension and shear testing. Background Art

[0002] In the fields of materials science, engineering mechanics and product development, tensile and shear performance testing of material samples is an important means to evaluate their mechanical properties and reliability.

[0003] Existing testing methods often rely on separately set tensile testing machines and shear testing machines to complete these two tests, which not only increases equipment cost and occupies space, but may also lead to inconsistencies between test data.

[0004] In shear tests, it is sometimes necessary to change the direction of shear force application to evaluate the shear performance of the sample in different directions. However, many existing testing machines usually need to re-fix the sample when adjusting the shear force direction, which not only increases the complexity of the test operation, but also may cause inconsistency in the test position due to the reinstallation of the sample, thus affecting the accuracy of the test results.

[0005] A key parameter of shear test is the force area, which directly affects the calculation of shear stress and the evaluation of shear performance of samples. However, many existing testing machines cannot accurately control the size of the force area when applying shear force, which limits the accuracy and flexibility of the test. Only a fixed force area can be selected for testing based on the design limitations of the testing machine, which may result in test results that cannot accurately reflect the true shear performance of the sample.

[0006] Therefore, it is necessary to provide a universal testing machine for tensile shear testing to solve the problems raised in the above background technology. Summary of the invention

[0007] To achieve the above object, the present invention provides the following technical solution: a universal testing machine for tensile shear testing, used for performing tensile shear testing on material samples, comprising:

[0008] Bracket;

[0009] A lower chuck is fixed in the middle of the bracket;

[0010] A tension plate, arranged at a certain distance above the lower chuck;

[0011] A tension hydraulic cylinder, arranged on the top of the bracket and connected to the tension plate;

[0012] An upper chuck, fixed below the tension plate;

[0013] A shearing force assembly is arranged between the lower chuck and the upper chuck, and a plurality of screw rods are connected around the shearing force assembly;

[0014] Wherein, the shear force component comprises:

[0015] A lifting frame, which is a ring-shaped double-layer hollow structure;

[0016] A plurality of shear blocks are arranged inside the lifting frame and are distributed in two circles up and down;

[0017] A plurality of shear hydraulic cylinders are distributed in the lifting frame to drive the shear block to move;

[0018] The upper and lower layers of the lifting frame are provided with a plurality of circumferentially distributed straight grooves, and the upper and lower shear blocks are respectively slidably connected to the corresponding straight grooves;

[0019] Furthermore, the lifting frame is provided with a rotating disk with an annular structure on the upper and lower sides, and a plurality of inclined grooves are distributed on the circumference of the rotating disk, and the diameter of the material sample is smaller than the diameter of the middle ring of the rotating disk;

[0020] A connecting pin is fixed above the shear block located at the upper layer, and a connecting pin is fixed below the shear block located at the lower layer.

[0021] Furthermore, a plurality of guide shafts are fixed around the tension disk, and the guide shafts slide through the top of the bracket.

[0022] Furthermore, a plurality of nuts are fixed around the lifting frame, and the screw rods are respectively threadedly connected to the nuts.

[0023] Furthermore, the screw is rotatably connected to the bracket at the bottom, a gear is fixedly connected to the lower end of the screw, a gear ring is rotatably arranged in the bracket, and the gear ring is meshed with each gear;

[0024] The bracket is also provided with a driving motor capable of driving the gear ring to rotate.

[0025] Furthermore, the edges of the two turntables are fixed together through a plurality of connecting columns, and a shear hydraulic cylinder is hinged between each of the connecting columns and the lifting frame.

[0026] Furthermore, a pressure sensor is provided inside each shear block, and the pressure sensor is used to detect and record in real time the pressure value to which each shear block is subjected during the test.

[0027] Furthermore, the connecting pin is a two-section telescopic structure, a spring is arranged inside the connecting pin, and the elastic force of the spring causes the telescopic section of the connecting pin to retract into the fixed section, and the height of the fixed section is flush with the height of the straight groove.

[0028] Furthermore, each of the inclined slots in the turntable is provided with an electromagnet, and when the electromagnet is energized, it can adsorb the telescopic section of the connecting pin so that the telescopic section passes through the inclined slot.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] In the present invention, the device not only has the traditional tensile test function, but also can realize the shear test function. By adjusting the height of the shear force component and the position of the shear force block, the needs of evaluating different mechanical properties of material samples can be met.

[0031] In the present invention, part of the shear blocks are selectively connected to the turntable by controlling the on and off of the electromagnet. The number and position of the shear blocks can be flexibly adjusted according to the characteristics of the sample and the test requirements, so as to achieve shear tests on different areas of the sample, thereby improving the pertinence and accuracy of the test. By making the two opposite shear blocks in the upper and lower layers apply shear force to the sample, the sample is subjected to a shear force that is staggered up and down, which helps to simulate the complex stress conditions in actual working conditions and can also more comprehensively evaluate the shear performance and deformation resistance of the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The figure is a schematic diagram of the structure of a universal testing machine for tension-shear testing.

[0033] Figure 2 This is a schematic diagram of the structure of the shear component.

[0034] Figure 3 Exploded diagram of the shear component.

[0035] Figure 4 This is a schematic diagram of the structure of the shear block.

[0036] Figure 5 This is a cross-sectional view of the shear component.

[0037] In the figure: 1. bracket; 2. lower chuck; 3. tension plate; 31. guide shaft; 4. tension hydraulic cylinder; 5. upper chuck; 6. shear assembly; 61. lifting frame; 62. shear block; 63. shear hydraulic cylinder; 64. straight slot; 65. turntable; 66. inclined slot; 67. connecting pin; 68. electromagnet; 69. connecting column; 610. nut; 7. screw; 71. gear; 8. gear ring. DETAILED DESCRIPTION

[0038] See also Figure 1 and Figure 2 In an embodiment of the present invention, a universal testing machine for tensile shear testing is used to perform tensile shear testing on a material sample, comprising:

[0039] Bracket 1;

[0040] A lower chuck 2 is fixed in the middle of the bracket 1;

[0041] A tension plate 3 is arranged at a certain distance above the lower chuck 2;

[0042] A tension hydraulic cylinder 4 is arranged on the top of the bracket 1 and connected to the tension plate 3;

[0043] An upper chuck 5 is fixed below the tension plate 3;

[0044] A shearing assembly 6 is arranged between the lower chuck 2 and the upper chuck 5, and a plurality of screws 7 are connected around the shearing assembly 6;

[0045] Wherein, the shear force component 6 comprises:

[0046] A lifting frame 61, which is an annular double-layer hollow structure;

[0047] A plurality of shear blocks 62 are arranged inside the lifting frame 61 and are distributed in two circles up and down;

[0048] A plurality of shear hydraulic cylinders 63 are distributed in the lifting frame 61 to drive the shear block 62 to move.

[0049] The upper chuck 5 and the lower chuck 2 are respectively used to clamp the two ends of the sample to be tested to perform a tensile test, and a shear test can be performed through the shear force component 6.

[0050] In this embodiment, a plurality of guide shafts 31 are fixed around the tension disk 3 , and the guide shafts 31 slide through the top of the bracket 1 .

[0051] The guide shaft 31 can limit the torque of the tension disk 3 and ensure that the tension disk 3 is lifted and lowered smoothly.

[0052] In this embodiment, a plurality of nuts 610 are fixed around the lifting frame 61 , and the screw rods 7 are respectively threadedly connected to the nuts 610 .

[0053] In this embodiment, the screw rod 7 is rotatably connected to the bracket 1 at the bottom, a gear 71 is fixedly connected to the lower end of the screw rod 7, a gear ring 8 is rotatably provided in the bracket 1, and the gear ring 8 is meshed with each gear 71;

[0054] The bracket 1 is also provided with a driving motor capable of driving the ring gear 8 to rotate.

[0055] Each screw rod 7 can be driven to rotate synchronously by a driving motor, so that the lifting frame 61 can be raised or lowered, thereby adjusting the height at which the shear force is applied to the sample.

[0056] See also Figure 3 and Figure 4 In this embodiment, the upper and lower layers of the lifting frame 61 are provided with a plurality of circumferentially distributed straight grooves 64 , and the upper and lower shear blocks 62 are respectively slidably connected to the corresponding straight grooves 64 .

[0057] In this embodiment, a rotating disk 65 with an annular structure is rotatably arranged on the upper and lower sides of the lifting frame 61, and a plurality of inclined grooves 66 are distributed on the circumference of the rotating disk 65, wherein the diameter of the material sample is smaller than the diameter of the middle ring of the rotating disk 65;

[0058] A connecting pin 67 is fixed above the shear block 62 located at the upper layer, and a connecting pin 67 is fixed below the shear block 62 located at the lower layer.

[0059] That is, when the turntable 65 rotates, it can push the corresponding connecting pin 67 to slide along the straight groove 64, thereby pushing the shear block 62 to slide in the radial direction, so that the shear block 62 applies shear force to the sample.

[0060] In this embodiment, the edges of the two turntables 65 are fixed together by a plurality of connecting columns 69 , and a shear hydraulic cylinder 63 is hinged between each of the connecting columns 69 and the lifting frame 61 .

[0061] The two turntables 65 can be rotated synchronously by the extension and retraction of the shear hydraulic cylinder 63, so that the shear blocks 62 corresponding to the upper and lower layers can slide synchronously, ensuring that the sample is subjected to uniform force.

[0062] In this embodiment, a pressure sensor is disposed inside each of the shear blocks 62 , and the pressure sensor is used to detect and record in real time the pressure value to which each shear block 62 is subjected during the test.

[0063] Through the pressure sensor, the control system can accurately obtain the stress conditions of the sample at different positions, further analyze the mechanical properties and stress distribution of the sample, and provide more accurate data support for scientific research and product development.

[0064] See also Figure 5 In this embodiment, the connecting pin 67 is a two-section telescopic structure with a spring inside. The elastic force of the spring causes the telescopic section of the connecting pin 67 to retract into the fixed section. The height of the fixed section is flush with the height of the straight slot 64.

[0065] In this embodiment, an electromagnet 68 is provided in each of the inclined slots 66 in the rotating disk 65 . When the electromagnet 68 is energized, it can adsorb the telescopic section of the connecting pin 67 so that the telescopic section passes through the inclined slot 66 .

[0066] When the electromagnet 68 is powered on, the rotation of the turntable 65 can drive the corresponding shear block 62 to slide, while when the electromagnet 68 is powered off, the rotation of the turntable 65 cannot drive the corresponding shear block 62 to slide because the connecting pin 67 leaves the inclined slot 66;

[0067] That is to say, by controlling the on and off of the electromagnet 68, it is possible to control whether the corresponding shear block 62 slides along with the rotation of the turntable 65. By making the two opposing shear blocks 62 in the upper and lower layers apply shear force to the sample, the sample can be subjected to a shear force that is staggered up and down, and the area and direction of the shear force on the sample can be controlled.

[0068] When it comes to specific implementation,

[0069] Equipment preparation and sample installation inspection equipment:

[0070] Clamp the two ends of the sample to be tested in the upper chuck 5 and the lower chuck 2 respectively, and ensure that the sample is firmly clamped to prevent it from falling off or sliding during the test.

[0071] Through the control system, the drive motor is started to rotate the ring gear 8, thereby driving all the screw rods 7 to rotate synchronously, and then adjusting the height of the lifting frame 61. As needed, the relative position between the shear assembly 6 and the sample is adjusted to facilitate subsequent shear testing.

[0072] Tensile test setting tension parameters:

[0073] The required parameters such as the stretching force and stretching speed are input into the control system, and the tension hydraulic cylinder 4 is started to rise slowly, and the tension is applied to the upper chuck 5 through the tension disk 3, thereby stretching the sample.

[0074] Observe and record the tensile behavior of the sample, including key data such as breaking point and maximum tensile force.

[0075] Shear test adjusts the shear block position:

[0076] As needed, by controlling the on and off of the electromagnet 68, some of the shear blocks 62 are selectively connected to the turntable 65. The rotation of the turntable 65 will drive the corresponding shear blocks 62 to slide along the straight groove 64, thereby applying shear force to the sample.

[0077] Parameters such as the required shear force, shear speed, and the moving path of the shear block 62 are input into the control system.

[0078] The shear hydraulic cylinder 63 is started to extend and retract, thereby driving the two turntables 65 to rotate synchronously. Through the interaction between the connecting pin 67 and the inclined slot 66, the shear blocks 62 corresponding to the upper and lower layers slide synchronously, applying uniform shear force to the sample.

[0079] Observe and record the shear behavior of the sample, including key data such as shear strength and shear deformation. During the test, the pressure value of each shear block 62 is monitored and recorded in real time by the control system.

[0080] End of test and data processing End of test:

[0081] When the sample reaches the predetermined breaking point or the test time is over, the operation of the tension hydraulic cylinder 4 and the shear hydraulic cylinder 63 is stopped. The power supply of the electromagnet 68 is turned off to disengage the connecting pin 67 from the inclined slot 66.

[0082] The data recorded during the test is imported into the data analysis software for further processing and analysis. Based on the analysis results, the mechanical properties and stress distribution of the samples are evaluated to provide guidance for subsequent scientific research and product development.

[0083] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A universal testing machine for tensile shear testing, used for performing tensile shear testing on material samples, characterized in that: include: Bracket (1); A lower chuck (2) is fixed to the middle of the bracket (1); A tension plate (3) is arranged at a certain distance above the lower chuck (2); A tension hydraulic cylinder (4), which is arranged on the top of the bracket (1) and connected to the tension plate (3); An upper chuck (5) is fixed below the tension plate (3); A shear force component (6) is arranged between the lower chuck (2) and the upper chuck (5), and a plurality of screw rods (7) are connected around the shear force component (6); Wherein, the shear component (6) comprises: A lifting frame (61) having an annular double-layer hollow structure; A plurality of shear blocks (62) are arranged inside the lifting frame (61) and are distributed in two circles in the upper and lower parts; A plurality of shear hydraulic cylinders (63) are distributed in the lifting frame (61) and drive the shear block (62) to move; The upper and lower layers of the lifting frame (61) are both provided with a plurality of circumferentially distributed straight grooves (64), and the upper and lower shear blocks (62) are respectively slidably connected to the corresponding straight grooves (64); A rotating disk (65) with an annular structure is rotatably arranged above and below the lifting frame (61), and a plurality of inclined grooves (66) are distributed on the circumference of the rotating disk (65). The diameter of the material sample is smaller than the diameter of the middle ring of the rotating disk (65); A connecting pin (67) is fixed above the shear block (62) located at the upper layer, and a connecting pin (67) is fixed below the shear block (62) located at the lower layer.

2. A universal testing machine for tensile shear testing according to claim 1, characterized in that: A plurality of guide shafts (31) are fixed around the tension plate (3), and the guide shafts (31) slide through the top of the bracket (1).

3. A universal testing machine for tensile shear testing according to claim 1, characterized in that: A plurality of nuts (610) are fixed around the lifting frame (61), and the screw rods (7) are respectively threadedly connected to the nuts (610).

4. A universal testing machine for tensile shear testing according to claim 1, characterized in that: The lower part of the screw rod (7) is rotatably connected to the bracket (1); a gear (71) is fixedly connected to the lower end of the screw rod (7); a gear ring (8) is rotatably provided in the bracket (1); the gear ring (8) meshes with each gear (71); A driving motor capable of driving the ring gear (8) to rotate is also provided in the bracket (1).

5. A universal testing machine for tensile shear testing according to claim 1, characterized in that: The edges of the two rotating disks (65) are fixed together via a plurality of connecting columns (69), and a shear hydraulic cylinder (63) is hingedly connected between each connecting column (69) and the lifting frame (61).

6. A universal testing machine for tensile shear testing according to claim 1, characterized in that: A pressure sensor is arranged inside each shear block (62), and the pressure sensor is used to detect and record in real time the pressure value exerted on each shear block (62) during the test.

7. A universal testing machine for tensile shear testing according to claim 1, characterized in that: The connecting pin (67) is a two-section telescopic structure, a spring is arranged inside the connecting pin, and the elastic force of the spring causes the telescopic section of the connecting pin (67) to retract into the fixed section, and the height of the fixed section is flush with the height of the straight groove (64).

8. A universal testing machine for tensile shear testing according to claim 7, characterized in that: Each inclined slot (66) in the rotating disk (65) is provided with an electromagnet (68). When the electromagnet (68) is energized, it can adsorb the telescopic section of the connecting pin (67) so that the telescopic section penetrates into the inclined slot (66).

Images