Sample piece auxiliary device for shear test and control method thereof

Abstract

The invention relates to the technical field of shear force testing, and discloses a sample piece auxiliary device for a shear test, which comprises a fixed frame with a hollow area, a first guide piece, a second guide piece, a first pressing plate, a second pressing plate, a second guide section and a third guide section, one end, deviating from the second guide section, of the first guide section is movably connected with an adjusting block, the first guide section is movably connected with a second pressing plate, the first pressing plate and the second pressing plate are driven to move in the axial direction, and the pressure sensor is pressed or released in the moving process. After pressure is loaded to the surface of the to-be-tested sample piece, the pressure sensor is not pressed any more and is convenient to take down, the testing process is simplified, operation is simpler and more convenient, and the preparation time before testing and the operation complexity in testing are reduced through quick release of the pressure sensor and real-time monitoring of the pressure value.

Description

Technical Field

[0001] The present invention relates to the technical field of shear force testing, in particular to a sample auxiliary device for a shear test and a control method thereof. Background Art

[0002] Structural bonding of power battery packs is one of the key technologies to ensure battery performance and safety. Shear testing of adhesives is a key means to evaluate the bonding strength and performance of adhesives under shear force. For structural bonding of power battery packs, two pieces of samples are usually bonded with adhesive in an overlapping form, and tensile force is applied along the axial direction to make the bonding interface withstand shear stress. However, for the shear test of double-sided adhesives for battery packs, a special fixture with a pressure sensor is required to apply a preset pressure to the test sample to simulate the pressing conditions in the actual assembly of the battery pack. The pressure sensor can monitor and feedback the pressure value in real time to ensure that the pressure is uniform and meets the test standards.

[0003] Since this test has precise requirements for the loaded pressure value and a small allowable error range, the existing pre-pressure auxiliary device usually presses the pressure sensor directly on the surface of the sample. However, during the tensile test, the sample will be stretched and displaced, so the sensor is easily damaged. If the pressure sensor is forcibly disassembled, the force state of the fixture will change during disassembly, resulting in instantaneous fluctuations in the pre-pressure and a large error range. In addition, the threaded interface or plug-in connector of the pressure sensor will also lead to a decrease in accuracy after repeated disassembly. Summary of the Invention

[0004] The purpose of the present invention is to provide a sample auxiliary device for shear testing with pre-pressure to solve the problems in the prior art. The preset pressure can be completely transferred to the sample to be tested, and the pressure sensor can be easily removed after the pressure loading is completed to avoid damage in subsequent shear tests.

[0005] The present invention provides a sample auxiliary device for shear test, comprising: A fixed frame having a hollow area for the sample to be tested to pass through; A first guide member, one end of which is movably connected to the fixing frame along the axial direction, and the other end of which is disposed in the hollow area and movably connected to the first pressing plate; The second guide member is provided with a first guide section and a second guide section along the axial direction, the first guide section is provided in the hollow area, the second guide section is movably connected to the fixed frame, an end of the first guide section facing away from the second guide section is movably connected to the adjustment block, and the first guide section is movably connected to the second pressure plate, and the second pressure plate can move axially between the adjustment block and the second guide section; The pressure sensor is arranged between the first pressing plate and the second pressing plate, and drives the first pressing plate and the second pressing plate to move along the axial direction, and compresses or releases the pressure sensor during the movement process.

[0006] In the sample auxiliary device for shear test as described above, preferably, the first guide member includes a symmetrically arranged first screw rod, and the connecting portion between the first screw rod and the first pressure plate is provided with a smooth rod portion.

[0007] A sample auxiliary device for a shear test as described above, wherein preferably, the second guide member includes a symmetrically arranged second screw, the first guide section is provided with a first thread, the second guide section is provided with a second thread, and the outer diameter of the first thread is smaller than the second thread.

[0008] In the sample auxiliary device for shear test as described above, preferably, a blocking piece is fixedly provided on a side of the second guide section facing the second pressing plate.

[0009] In the sample auxiliary device for shear test as described above, preferably, the adjustment block includes a screw sleeve, the screw sleeve is threadedly connected to the first thread segment, and the pitch of the first thread is smaller than the pitch of the second thread.

[0010] In the sample auxiliary device for shear test as described above, preferably, the second pressing plate and the fixing frame are respectively provided with clamping assemblies, the two clamping assemblies are arranged opposite to each other, and the sample to be tested is placed between the two clamping assemblies.

[0011] As described above, in the sample auxiliary device for shear test, preferably, the clamping assembly includes a pressure roller and an axle pin, and the pressure roller is connected to the fixing frame and the second pressure plate respectively through the axle pin.

[0012] In the sample auxiliary device for shear test as described above, preferably, the pressure sensor includes a thin film pressure sensor.

[0013] The control method of the sample auxiliary device for the shear test includes the following steps: S1. Place the sample to be tested in the hollow area, and place the pressure sensor in the gap between the first pressing plate and the second pressing plate; S2, driving the first pressing plate to move toward the sample to be tested until the pressure value displayed by the pressure sensor reaches a preset value K; S3, driving the second pressing plate to move toward the sample to be tested, and stopping when the pressure sensor value drops to 10-20% of the preset value K; S4. Repeat steps S2-S3. When the second pressure plate presses against the sample to be tested and the second pressure plate is separated from the end of the second guide section, drive the first pressure plate toward the second pressure plate until the pressure sensor displays a pressure value that is a preset value K. Then drive the second pressure plate toward the sample to be tested until the value of the pressure sensor drops to 0, thereby completing the pressure loading of the sample to be tested.

[0014] A control method for a sample auxiliary device for a shear test as described above, wherein preferably, in step S4, when the second pressure plate is separated from the second guide section, the adjustment block is driven to press the second pressure plate until the pressure value drops to 0 and stops, and the adjustment block limits the side of the second pressure plate away from the sample to be tested. After the pressure loading is completed, the first pressure plate is driven to move in the direction away from the sample to be tested until the gap between the first pressure plate and the second pressure plate is greater than the thickness of the pressure sensor, and then the pressure sensor is removed.

[0015] Compared with the existing technology, the present invention uses the first and second pressure plates in conjunction with the pressure sensor to obtain a preset pressure, ensuring more precise pressure control during the test process. The dynamic displacement of the pressure center ensures that the pressure is evenly distributed on the surface of the test sample, avoiding deviations in test results caused by uneven pressure distribution. By cooperating with the second pressure plate, the pressure sensor can be freed from pressure after the pressure is applied to the surface of the sample to be tested, making it easy to remove and thus protecting the sensor from damage. This not only extends the service life of the sensor but also avoids test interruptions caused by sensor damage. The present invention simplifies the testing process, makes the operation more convenient, and reduces the preparation time before the test and the complexity of the operation during the test through the rapid release of the pressure sensor and the real-time monitoring of the pressure value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional diagram of a sample to be tested provided by an embodiment of the present invention; Figure 2 is a perspective view of a sample auxiliary device for a shear test provided by an embodiment of the present invention; Figure 3 is a top view of a sample auxiliary device for a shear test provided by an embodiment of the present invention; Figure 4 yes Figure 3 A magnified view of point A in the figure; Figure 5 is a cross-sectional view of a sample auxiliary device for a shear test provided by an embodiment of the present invention; Figure 6 yes Figure 5 Enlarged view of point B in FIG. Figure 7 is a perspective view of a first screw provided by an embodiment of the present invention; Figure 8 is a perspective view of a second screw provided by an embodiment of the present invention; Figure 9 is a three-dimensional diagram of a clamping assembly provided by an embodiment of the present invention.

[0017] Description of reference numerals: 10. Fixed frame; 11. Hollow area; 20, first guide member; 200, first screw; 201, polished rod; 21, first pressing plate; 30. Second guide member; 300. Second screw; 31. First guide section; 310. First thread; 32. Second guide section; 320. Second thread; 33. Adjustment block; 330. Screw sleeve; 34. Second pressure plate; 35. Stopper; 36. Butterfly knob; 40. Pressure sensor; 50. Clamping assembly; 51. Pressing roller; 52. Axle pin; 60. Sample to be tested; 61. Sheared sample; 62. Adhesive. DETAILED DESCRIPTION

[0018] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limiting the present invention.

[0019] See also Figure 1 As shown, the sample 60 to be tested for the shear test includes two shear samples 61 arranged opposite to each other, and the ends of the two shear samples 61 are bonded together by an adhesive 62 .

[0020] See also Figure 2-6 As shown, this embodiment provides a sample auxiliary device for a shear test, which is used to apply a preset pressure of a preset value K to the bonding portion of a sample 60 to be tested, and remove the pressure sensor 40 after the pressure loading is completed. The sample auxiliary device includes a fixing frame 10, a first guide member 20, and a second guide member 30, wherein: The fixing frame 10 has a hollow area 11 for the sample 60 to be tested to pass through; one end of the first guide member 20 is movably connected to the fixing frame 10 along the axial direction, and the other end is arranged in the hollow area 11, and the end is movably connected to the first pressure plate 21; the second guide member 30 is axially provided with a first guide section 31 and a second guide section 32, the first guide section 31 is arranged in the hollow area 11, and the second guide section 32 is movably connected to the fixing frame 10, and the end of the first guide section 31 facing away from the second guide section 32 is movably connected to the adjustment block 33, and the first guide section 31 is movably connected to the second pressure plate 34, and the second pressure plate 34 can move axially between the adjustment block 33 and the second guide section 32; the pressure sensor 40 is arranged between the first pressure plate 21 and the second pressure plate 34, driving the first pressure plate 21 and the second pressure plate 34 to move axially, and compressing or releasing the pressure sensor 40 during the movement process.

[0021] See also Figure 3As shown, in this embodiment, the fixed frame 10 is a frame-like structure. The hollow area 11 provides space for movement of components such as the test sample 60, the first pressure plate 21, and the second pressure plate 34. This allows for the device to accommodate samples of varying sizes and enhances its versatility. The first and second guide members 20 and 30 guide the movement of the first and second pressure plates 21 and 34. The symmetrical arrangement of the first and second pressure plates 21 and 34 ensures uniform pressure transmission.

[0022] Initially, the test sample 60 is positioned vertically within the hollow region 11, with a certain gap between the second pressure plate 34 and the test sample 60. The test sample 60 can be handheld, or more conveniently, the fixture 10 can be placed on a tabletop so that the test sample 60 is horizontal and in contact with the inner wall of the fixture 10. The first and second pressure plates 21 and 34 first preload a pressure of a preset value K, then transmit the preset pressure value K to the test sample 60. By driving the first and second guide members 20 and 30, the pressure state of the pressure sensor 40 is dynamically adjusted. The second pressure plate 34 is axially movable on the first guide section 31. Therefore, by controlling the relative displacement of the second pressure plate 34, sufficient space is provided for removing the pressure sensor 40 after pressure loading is completed.

[0023] See also Figure 7 As shown, in a feasible embodiment, the first guide member 20 includes a symmetrically arranged first screw rod 200 , and a polished rod portion 201 is provided at the connection portion between the first screw rod 200 and the first pressing plate 21 . The fixing frame 10 is provided with a threaded hole that cooperates with the first screw 200. The first screw 200 cooperates with the threaded hole of the fixing frame 10 to form a spiral transmission mechanism, which can accurately adjust the displacement of the first pressure plate 21, and the self-locking property of the threaded transmission can keep the first screw 200 in a fixed position after stopping rotation, preventing the first pressure plate 21 from being displaced and changing due to vibration or external force. The first screw 200 is movably connected to the first pressure plate 21. When the first screw 200 moves toward the direction of the sample 60 to be tested, it can drive the first pressure plate 21 to move, and the connecting part is provided with a smooth rod portion 201. The diameter of the smooth rod portion 201 is smaller than the outer diameter of the first screw 200 to avoid friction resistance caused by thread engagement. When the first screw 200 moves away from the sample 60 to be tested, the gap between the first pressure plate 21 and the second pressure plate 34 increases, and the first pressure plate 21 and the first screw 200 can be directly removed from the fixing frame 10, reducing the weight of the auxiliary device during the shear test and reducing errors.

[0024] See also Figure 8As shown, the second guide member 30 includes a symmetrically arranged second screw 300, a first thread 310 is provided on the first guide section 31, and a second thread 320 is provided on the second guide section 32. The outer diameter of the first thread 310 is smaller than the outer diameter of the second thread 320. The two second screws 300 are located on both sides of the sample 60 to be tested. The aperture of the second pressure plate 34 is larger than the outer diameter of the first thread 310 and smaller than the outer diameter of the second thread 320. In this way, the second pressure plate 34 can move axially at the first thread 310, and can be restricted by the end of the second thread 320 to move to the second guide section 32. When the first pressure plate 21 and the second pressure plate 34 clamp the pressure sensor 40 in the initial stage, since the second pressure plate 34 has not yet contacted the sample 60 to be tested, the second pressure plate 34 will press against the end of the second thread 320. When the second pressure plate 34 contacts the sample 60 to be tested, the second pressure plate 34 will separate from the end of the second thread 320. At this time, the pressure between the second pressure plate 34 and the sample 60 to be tested is 0, which is at the critical point of pressure transfer. After ensuring that the pressure between the first pressure plate 21 and the second pressure plate 34 is the preset value K, the second pressure plate 34 is driven to move toward the sample 60 to be tested. The pressure of the preset value K can be completely transferred to the sample 60 to be tested, and during the transfer process, the gap between the first pressure plate 21 and the second pressure plate 34 increases, providing disassembly space for the pressure sensor 40.

[0025] The ends of the first screw 200 and the second screw 300 are each provided with a butterfly knob 36 for convenient manual operation, thereby achieving infinite adjustment. The butterfly knob 36 on the second screw 300 can also lock the second screw 300 after pressure transfer to the test sample 60 is completed, preventing displacement during subsequent tests. In this embodiment, the first guide member 20 and the second guide member 30 can also be achieved by using a screw and nut pair to achieve axial movement. Of course, other axially movable components can also be used, but they must be equipped with corresponding limit components to achieve a self-locking function. This is not limited here, but for the sake of lightweight design, a screw structure is preferably used.

[0026] See also Figure 3-4 As shown, in this embodiment, a baffle 35 is fixedly provided on the side of the second guide section 32 facing the second pressure plate 34. The baffle 35 has a larger area and can better prevent the second pressure plate 34 from moving onto the second guide section 32. When the second pressure plate 34 contacts the test sample 60, the baffle 35 will separate from the second pressure plate 34, so that the critical position of pressure transfer can be determined.

[0027] See also Figure 8As shown, the adjustment block 33 includes a threaded sleeve 330, which is threadedly connected to the first thread 310. The pitch of the first thread 310 is smaller than the pitch of the second thread 320. The first thread 310 and the threaded sleeve 330 can achieve precise control of displacement and a self-locking function. When pressure is transferred to the sample 60 to be tested, the smaller pitch of the first thread 310 allows for fine adjustment, while the larger pitch of the second thread 320 can drive the second pressure plate 34 to move to the sample 60 to be tested more quickly. Of course, the adjustment block 33 can also be other components with a locking structure.

[0028] See also Figure 3 As shown, in this embodiment, a clamping assembly 50 is provided on each of the first pressing plate 21 and the fixing frame 10. The two clamping assemblies 50 are arranged opposite each other, and the sample 60 to be tested is placed between the two clamping assemblies 50. The two clamping assemblies 50 are symmetrically arranged, and the clamping assemblies 50 clamp the sample 60 to be tested, so that the preset pressure can be transferred to the sample 60 to be tested more concentratedly.

[0029] See also Figure 9 As shown, in a feasible embodiment, the clamping assembly 50 includes a pressure roller 51 and an axle pin 52, and the pressure roller 51 is connected to the fixed frame 10 and the second pressure plate 34 respectively through the axle pin 52. The contact surface between the pressure roller 51 and the sample 60 to be tested is a cylindrical surface. This design can reduce the additional error caused by contact pressure. Compared with plane contact, cylindrical surface contact can more evenly disperse the pressure, reduce local stress concentration, and thus improve the reliability of the test data. In addition, the pressure roller 51 and the surface of the sample 60 to be tested are in rolling contact, and the axle pin 52 can make the pressure roller 51 rotate around the axis. When the sample 60 to be tested is displaced by shear force during the shear test, the pressure roller 51 rolls synchronously, and the friction resistance is greatly reduced, thereby reducing the stress concentration caused by the fixture resistance, and making the fracture position more accurately reflect the weak area of ​​the material.

[0030] See also Figure 2-3 As shown, in this embodiment, the pressure sensor 40 includes a thin film pressure sensor 40. The thin film pressure sensor 40 is easy to clamp, and one end of the thin film pressure sensor 40 is connected to a display screen to display the pressure value in real time. This embodiment also provides a control method for the sample auxiliary device of the shear test, including the following steps: S1. Place the sample 60 to be tested in the hollow area 11 and the pressure sensor 40 in the gap between the first pressing plate 21 and the second pressing plate 34; S2, driving the first pressing plate 21 to move toward the test sample 60 until the pressure sensor 40 displays a pressure value that is a preset value K; S3, driving the second pressing plate 34 to move toward the test sample 60, and stopping when the value of the pressure sensor 40 drops to 10-20% of the preset value K; S4. Repeat steps S2-S3. When the second pressure plate 34 presses against the sample 60 to be tested and the second pressure plate 34 is separated from the end of the second guide section 32, drive the first pressure plate 21 to move toward the second pressure plate 34 until the pressure sensor 40 displays the pressure value as the preset value K. Then drive the second pressure plate 34 to move toward the sample 60 to be tested until the value of the pressure sensor 40 drops to 0, completing the pressure loading of the sample 60 to be tested.

[0031] In step S1, in the initial stage, one side of the test sample 60 is in contact with the pressure roller 51 on the fixed frame 10 but no pressure is applied, and there is a small gap between the other side and the pressure roller 51 on the second pressure plate 34. At this time, the test sample 60 can be kept from moving by holding it or other means.

[0032] The purpose of steps S2-S3 is to achieve dynamic displacement of the pressure center, evenly distributing the pressure of the preset value K across the surface of the test sample 60, improving test accuracy and avoiding test result deviations caused by uneven pressure distribution. When releasing the pressure, the pressure value must not reach zero to prevent the pressure sensor 40 from falling through the gap between the first and second pressure plates 21 and 34. As a preferred approach, repeating step S2 when the pressure value drops to 10% of the preset value K not only prevents the pressure sensor 40 from falling, but also reduces the number of repetitions.

[0033] In step S4, when the second pressure plate is separated from the second guide section, the driving adjustment block 33 presses the second pressure plate 34 until the pressure value drops to 0, and the adjustment block 33 limits the side of the second pressure plate 34 away from the sample to be tested 60. After the pressure loading is completed, the first pressure plate 21 is driven to move in the direction away from the sample to be tested 60 until the gap between the first pressure plate 21 and the second pressure plate 34 is greater than the thickness of the pressure sensor 40, and then the pressure sensor 40 is removed.

[0034] It should be noted that, in this embodiment, since a baffle 35 is provided on the side of the second guide section 32 facing the second pressure plate 34, when the second pressure plate 34 is separated from the baffle 35, it indicates that the second pressure plate 34 has contacted the sample to be tested 60, and the second pressure plate 34 can move axially between the adjustment block 33 and the baffle 34. Therefore, at this time, the pressure between the second pressure plate 34 and the sample to be tested 60 is 0, and the first screw 200 is moved to the pressure value of the preset value K, indicating that the pressure between the first pressure plate 21 and the second pressure plate 34 is the preset value K, and the pressure between the second pressure plate 34 and the sample to be tested 60 is 0. Driving the second pressure plate 34 to move toward the sample to be tested 60 can ensure that the pressure transmitted to the sample to be tested 60 is just the complete preset pressure. Of course, during the final step of transferring pressure, the second guide member 30 can also be driven to allow the adjustment block 33 and the test sample 60 to fit together until the pressure value of the pressure sensor 50 drops to 0. The end of the second guide member 30 connected to the fixing frame 10 can be self-locked by the second thread 320 on the second screw 300, or can be further fixed by the butterfly knob 36. In addition, a slight error in pressure loading is allowed during the test, but this device can reduce the error to a minimum.

[0035] During the process of the second pressure plate 34 transferring pressure to the sample 60 to be tested, the gap between the second pressure plate 34 and the first pressure plate 21 increases. The pressure sensor 40 does not need to continue to monitor the pressure value. Therefore, the gap can be further increased by reverse driving the first pressure plate 21 to facilitate the removal of the pressure sensor 40.

[0036] This control method drives the first pressure plate 21 and the second pressure plate 34 to move and repeatedly clamp or release the pressure value of the pressure sensor 40, dynamically transferring the pressure of the preset value K to the sample 60 to be tested. The pressure sensor 40 can display the pressure value in real time to ensure that the pressure control during the test is more accurate. Compared with the existing technology, it can more effectively avoid test errors caused by improper pressure control. In addition, this control method simplifies the test process, reduces the preparation time before the test and the complexity of the operation during the test. It should be noted that the embodiment provided by the present invention is not only applicable to the pre-shear test assistance of the bonding structure of the battery pack, but also applicable to other samples that need to apply a preset pressure to the sample 60 to be tested during the shear test, and is not limited here.

[0037] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the scope of implementation of the present invention is not limited to what is shown in the drawings. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which do not exceed the spirit covered by the description and drawings, should be within the scope of protection of the present invention.

Claims

1. A sample auxiliary device for shear test, characterized in that: include: A fixed frame having a hollow area for the sample to be tested to pass through; A first guide member, one end of which is movably connected to the fixing frame along the axial direction, and the other end of which is disposed in the hollow area and movably connected to the first pressing plate; The second guide member is provided with a first guide section and a second guide section along the axial direction, the first guide section is provided in the hollow area, the second guide section is movably connected to the fixed frame, an end of the first guide section facing away from the second guide section is movably connected to the adjustment block, and the first guide section is movably connected to the second pressure plate, and the second pressure plate can move axially between the adjustment block and the second guide section; The pressure sensor is arranged between the first pressing plate and the second pressing plate, and drives the first pressing plate and the second pressing plate to move along the axial direction, and compresses or releases the pressure sensor during the movement process.

2. The sample auxiliary device for shear test according to claim 1, characterized in that: The first guide member includes a first screw rod that is symmetrically arranged, and a polished rod portion is provided at a connection portion between the first screw rod and the first pressing plate.

3. The sample auxiliary device for shear test according to claim 1, characterized in that: The second guide member includes a symmetrically arranged second screw rod, the first guide section is provided with a first thread, the second guide section is provided with a second thread, and the outer diameter of the first thread is smaller than the second thread.

4. The sample auxiliary device for shear test according to claim 1, characterized in that: A blocking piece is fixedly provided on one side of the second guide section facing the second pressing plate.

5. The sample auxiliary device for shear test according to claim 3, characterized in that: The adjusting block includes a threaded sleeve, which is threadedly connected to the first thread segment, and the pitch of the first thread is smaller than the pitch of the second thread.

6. The sample auxiliary device for shear test according to claim 1, characterized in that: The second pressing plate and the fixing frame are respectively provided with clamping assemblies, the two clamping assemblies are arranged opposite to each other, and the sample to be tested is placed between the two clamping assemblies.

7. The sample auxiliary device for shear test according to claim 6, characterized in that: The clamping assembly includes a pressure roller and an axle pin, and the pressure roller is connected to the fixing frame and the second pressure plate respectively through the axle pin.

8. The sample auxiliary device for shear test according to claim 1, characterized in that: The pressure sensor includes a thin film pressure sensor.

9. A control method for a sample auxiliary device for a shear test according to any one of claims 1 to 8, characterized in that: The steps include: S1. Place the sample to be tested in the hollow area, and place the pressure sensor in the gap between the first pressing plate and the second pressing plate; S2, driving the first pressing plate to move toward the sample to be tested until the pressure value displayed by the pressure sensor reaches a preset value K; S3, driving the second pressing plate to move toward the sample to be tested, and stopping when the pressure sensor value drops to 10-20% of the preset value K; S4. Repeat steps S2-S3. When the second pressure plate presses against the sample to be tested and the second pressure plate is separated from the end of the second guide section, drive the first pressure plate toward the second pressure plate until the pressure sensor displays a pressure value that is a preset value K. Then drive the second pressure plate toward the sample to be tested until the value of the pressure sensor drops to 0, thereby completing the pressure loading of the sample to be tested.

10. The control method of the sample auxiliary device for shear test according to claim 9, characterized in that: In step S4, when the second pressure plate is separated from the second guide section, the driving adjustment block presses the second pressure plate until the pressure value drops to 0 and stops. The adjustment block limits the side of the second pressure plate away from the sample to be tested. After the pressure loading is completed, the first pressure plate is driven to move in the direction away from the sample to be tested until the gap between the first pressure plate and the second pressure plate is greater than the thickness of the pressure sensor, and then the pressure sensor is removed.

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