Rubber product elasticity detection equipment and detection method

Abstract

The invention relates to the technical field of rubber product detection, in particular to a rubber product elasticity detection device and method, and the device comprises a testing machine which is provided with a driving mechanism and a bearing platform; a bottom die is locked on the bearing table, a loading groove is formed in the bottom die, and the loading groove is used for interference assembly of a test object; a constant pressure part is fixedly mounted at the output end of the driving mechanism; the top of the bottom die is designed to be an open channel, and the constant pressure part can enter the channel and apply axial pressure to a test object; a loading groove is formed in the bottom die, a metering structure used for detecting the reset height of a test object is installed at the inner top of the bottom die, a reaction cavity is further formed in the bottom die, and the reaction cavity communicates with the inner bottom of the circumferential edge of the loading groove. And the rubber product with rubber creep deformation can also be monitored.

Description

Technical Field

[0001] The invention relates to the technical field of rubber product detection, and in particular to a rubber product elasticity detection device and a detection method. Background Art

[0002] Rubber products refer to various products made of natural rubber or synthetic rubber. These products are widely used in various fields such as industry, agriculture, national defense, transportation, machinery manufacturing, medical care and daily life due to the excellent properties of rubber materials such as elasticity, wear resistance, corrosion resistance, insulation and vibration resistance.

[0003] Some rubber products need to withstand repeated stretching and recovery for a long time during use. To cope with such working conditions, they need to have good elasticity and durability, such as rubber belts, rubber shock absorbers, sealing rings and elastic gaskets. Therefore, rubber products need to be tested for their elasticity before being put into use, especially their recovery ability. Rubber products such as rubber gaskets and shock absorbers need to be reciprocatedly compressed and restored. Summary of the invention

[0004] The invention provides a rubber product elasticity detection device, which can detect the elastic recovery ability of the rubber product and monitor the rubber product with rubber creep.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A rubber product elasticity testing device, comprising:

[0007] A testing machine, wherein the testing machine is provided with a driving mechanism and a bearing platform;

[0008] A bottom mold is locked on the bearing platform, and a loading slot is provided inside the bottom mold, and the loading slot is used for interference fitting the test object;

[0009] A constant pressure portion is fixedly mounted on the output end of the driving mechanism;

[0010] The top of the bottom mold is designed as an open channel, and the constant pressure part can enter the channel and apply axial pressure to the test object;

[0011] A metering structure for detecting the reset height of the test object is installed on the inner top of the bottom mold.

[0012] Optionally, a reaction chamber is further provided inside the bottom mold, and the reaction chamber is connected to the inner bottom at the circumferential edge of the loading slot. When the test object is interference fit in the loading slot, the test object isolates the connection between the reaction chamber and the loading slot, and the interior of the reaction chamber is under negative pressure.

[0013] Optionally, a plurality of adaptive cylinders are installed at the top of the bottom mold, and an annular limit plate is commonly installed at the output end of the adaptive cylinder. The outer edge of the annular limit plate can slide like a piston with the inner wall of the loading slot. When driven by the adaptive cylinder, the bottom of the annular limit plate always conflicts with the top of the test object.

[0014] Optionally, the measuring structure includes a measuring rod fixedly mounted on an annular limit plate, the measuring rod passing through an inner top of the bottom mold, and a measuring scale is marked on the outer wall of the measuring rod, the top of the measuring rod is a reflective surface, and a miniature laser rangefinder is installed on the testing machine, and the laser rangefinder can measure the distance between the top of the measuring rod and the laser rangefinder.

[0015] Optionally, a guide column is fixedly installed on the inner bottom of the loading slot, and the test object can be sleeved on the outside of the guide column. A guide hole is opened on the constant pressure part, and the guide hole forms a guiding fit with the outer wall of the guide column.

[0016] Optionally, the outer wall of the guide column near the bottom end is covered with a flexible pressure sensor sheet, and the flexible pressure sensor sheet is composed of a flexible substrate, a conductive layer, a pressure-sensitive layer and a protective layer from the inside to the outside. The test object will be sleeved on the outer wall of the protective layer before testing, and the flexible pressure sensor sheet is associated with an external digital display system.

[0017] Optionally, the reaction chamber is divided into a plurality of identical micro chambers, and each of the micro chambers is equipped with an air pressure sensor.

[0018] A method for detecting elasticity of a rubber product, the method is implemented by using the rubber product elasticity detection device and an external negative pressure device, and the method comprises the following steps:

[0019] S1: Sleeve the test object on the outer wall of the guide column and the flexible pressure sensor sheet, and record the height of the top of the measuring rod;

[0020] S2: Turn on the testing machine, so that the driving mechanism drives the constant pressure part to enter the loading slot and reciprocately compress the top of the test object;

[0021] S3: After the preset number of compressions, the height of the top of the measuring rod is measured to detect the recovery ability of the test object;

[0022] S4: Associating the negative pressure device with the reaction chamber to make the inside of the reaction chamber a negative pressure state, and using an air pressure sensor to detect the negative pressure state of the reaction chamber to detect whether rubber creep occurs in the test object.

[0023] Optionally, in S4, it further includes:

[0024] V1: records the initial pressure value of the flexible pressure sensor;

[0025] V2: After rubber creep occurs, check whether the tightening force or internal stress of the test object on the flexible pressure sensing sheet is relaxed.

[0026] Optionally, in S1, a self-checking step is also included:

[0027] T1: Connect the negative pressure device to the reaction chamber, so that the inside of the reaction chamber is in a negative pressure state, and use the up and down displacement of the annular limit piece to put the test object in an interference fit state;

[0028] T2: The annular limit piece moves upward, releases the resistance to the top of the test object and detaches from the inner wall of the loading slot, and releases the top of the test object;

[0029] T3: Detect the negative pressure state of the reaction chamber. If the negative pressure state of the reaction chamber remains unchanged, it is determined that the interference fit of the test object is normal, and the subsequent rubber creep test steps can be carried out.

[0030] The present invention provides a rubber product elasticity detection device and a detection method, which achieve the following beneficial effects:

[0031] 1. By designing the cooperation between the bottom mold and the loading groove, the test object can be installed by interference fit, and the test object can be limited. When the constant pressure part is controlled by the driving mechanism to move back and forth, the constant pressure part can apply axial pressure to the top of the test object, so that the test object can cycle between compression and recovery. When the compression amount remains unchanged or the pressure is constant, when a certain number of compressions or compression cycles are reached, the elastic recovery ability of the test object can be determined by detecting the recovery height of the test object.

[0032] Second, since the reaction chamber is in a negative pressure state, while the loading slot is in a normal state, there is a pressure difference between the two. If the test object undergoes rubber creep, its shape will change, resulting in failure of the interference fit. At this time, the loading slot and the reaction chamber will be connected, thereby invalidating the negative pressure state of the reaction chamber, thereby determining whether the test object undergoes rubber creep.

[0033] 3. By monitoring the tightening force or stress applied by the test object to the flexible pressure sensing sheet, it is possible to determine whether stress relaxation occurs in the test object. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the external three-dimensional structure of the present invention;

[0035] Figure 2 It is a three-dimensional structural schematic diagram of the bottom mold and the metering structure in the present invention;

[0036] Figure 3 For the present invention Figure 2 A right view structural diagram of ;

[0037] Figure 4 For the present invention Figure 3 The schematic diagram of the structure is a cross-section at AA in the middle;

[0038] Figure 5 It is a schematic diagram of a three-dimensional half-section structure inside the bottom mold of the present invention;

[0039] Figure 6 It is a schematic diagram of the external three-dimensional structure of the bottom mold of the present invention;

[0040] Figure 7 It is a schematic diagram of the three-dimensional structure of the guide column and the flexible pressure sensing sheet in the present invention.

[0041] In the figure: 1. testing machine; 2. bottom mold; 3. constant pressure part; 4. guide column; 5. driving mechanism; 6. reaction chamber; 7. measuring rod; 8. annular limit plate; 9. adaptive cylinder; 11. flexible pressure sensor. DETAILED DESCRIPTION

[0042] The following will be combined with the 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 described embodiments 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 creative work are within the scope of protection of the present invention.

[0043] See also Figures 1 to 7 The present invention provides a technical solution: a rubber product elasticity detection device, comprising:

[0044] The testing machine 1 is provided with a driving mechanism 5 and a supporting platform; a bottom mold 2 is locked on the supporting platform, a loading groove is provided inside the bottom mold 2, and the loading groove is used for interference fitting the test object; a constant pressure part 3 is fixedly installed at the output end of the driving mechanism 5; the top of the bottom mold 2 is designed as an open channel, and the constant pressure part 3 can enter the channel and apply axial pressure to the test object; a metering structure for detecting the reset height of the test object is installed on the inner top of the bottom mold 2.

[0045] In the present invention, by designing the cooperation between the bottom mold 2 and the loading groove, the test object can be installed by interference fit, and the test object can be limited. When testing is required, the driving mechanism 5 is used to control the constant pressure part 3 to move back and forth, so that the constant pressure part 3 can apply axial pressure to the top of the test object, so that the test object can cycle between compression and recovery. When the compression amount remains unchanged or the pressure is constant, after reaching a certain number of compressions or compression cycles, by detecting the recovery height of the test object, it can be determined whether the elastic recovery ability of the test object is destroyed or weakened, thereby effectively evaluating the elastic recovery ability of the rubber gasket and ensuring its reliability and durability in practical applications.

[0046] During the test, the environment needs to be controlled to ensure that the temperature and humidity of the test environment are stable to avoid the influence of environmental factors on the test results, and to ensure that the compression or pressure of the constant pressure part 3 on the test object is constant so that the test process can meet the test standards, such as ASTMD395 and ISO815.

[0047] In a more preferred embodiment, a reaction chamber 6 is further provided inside the bottom mold 2, and the reaction chamber 6 is connected with the inner bottom at the circumferential edge of the loading groove. When the test object is interference fit in the loading groove, the test object isolates the connection between the reaction chamber 6 and the loading groove, and the inside of the reaction chamber 6 is negative pressure.

[0048] Repeated compression and recovery will cause rubber to creep. This is because under the repeated cyclic stress, the molecular chains of rubber materials will continue to slip and rearrange, gradually accumulating permanent deformation. As the number of cycles increases, the rubber will undergo irreversible permanent deformation, and the thickness will gradually decrease or the shape will change. Therefore, it is necessary to monitor or inspect the rubber creep. In the present invention, please refer to Figure 4 In a normal state, the test object is interference fit in the loading slot. At this time, the test object in the initial state will use the interference fit as a partition to disconnect the reaction chamber 6 from the loading slot. When testing is required, since the inside of the reaction chamber 6 is in a negative pressure state and the loading slot is in a normal state, there is a pressure difference between the two. If the test object undergoes rubber creep, its shape will change, resulting in failure of the interference fit. At this time, the loading slot and the reaction chamber 6 will be connected, thereby failing the negative pressure state of the reaction chamber 6, thereby determining whether the test object undergoes rubber creep. Even if rubber creep does not occur, a deformation accident will occur.

[0049] Furthermore, a plurality of adaptive cylinders 9 are installed at the top of the bottom mold 2, and an annular stopper 8 is installed at the output end of the adaptive cylinder 9. The outer edge of the annular stopper 8 can slide with the inner wall of the loading groove in a piston-like manner. Under the drive of the adaptive cylinder 9, the bottom of the annular stopper 8 always conflicts with the top of the test object. Please refer to Figure 4In this embodiment, when the test object is compressed, the tracking action of the annular limit plate 8 can assist the constant pressure part 3 to complete the reciprocating compression action. When the test object returns to its original state, it will push the annular limit plate 8 upward, and the adaptive cylinder 9 can also feel the recovery stress of the test object.

[0050] Furthermore, the metering structure includes a measuring rod 7 fixedly mounted on the annular limiting piece 8, the measuring rod 7 passes through the inner top of the bottom mold 2, and the outer wall of the measuring rod 7 is marked with a metering scale, the top of the measuring rod 7 is a reflective surface, and a miniature laser rangefinder is installed on the testing machine 1, and the laser rangefinder can measure the distance between the top of the measuring rod 7 and the laser rangefinder. In this embodiment, since the annular limiting piece 8 will follow the top displacement of the test object, the metering scale on the measuring rod 7 can display the height of the test object, and an accurate digitally displayable metering method is also designed, using the laser emitted by the laser rangefinder and the rebound path to determine the height of the measuring rod 7 and the test object. Specifically, when the elastic recovery ability of the test object is weakened, the recovery time and recovery stroke of the test object will change. Since it is a compressive pressure, the height or thickness of the test object reflects its elastic ability. Therefore, the thickness or height change of the test object can be accurately and real-time detected by the laser rangefinder and the measuring rod 7.

[0051] Furthermore, a guide column 4 is fixedly installed at the inner bottom of the loading slot, and the test object can be sleeved on the outside of the guide column 4. A guide hole is opened on the constant pressure part 3, and the guide hole forms a guide match with the outer wall of the guide column 4. The outer wall of the guide column 4 near the bottom is covered with a flexible pressure sensor sheet 11. The flexible pressure sensor sheet 11 is composed of a flexible substrate, a conductive layer, a pressure-sensitive layer and a protective layer from the inside to the outside. The test object will be sleeved on the outer wall of the protective layer before detection, and the flexible pressure sensor sheet 11 is associated with the external digital display system. Please refer to Figure 4 , Figure 6 and Figure 7 In this embodiment, when rubber creep occurs in the test object, stress relaxation will also occur synchronously. Under constant deformation, the internal stress of the test object gradually decreases over time, which will cause the fastening force of the test object to decrease, affecting its durability and reliability, that is, the fastening force or internal stress of the test object on the flexible pressure sensing sheet 11. When the internal stress or fastening force is reduced, the pressure applied by the test object to the flexible pressure sensing sheet 11 will also be reduced, so that the specific situation or early warning can be easily judged by the change in the pressure value of the flexible pressure sensing sheet 11.

[0052] Furthermore, the reaction chamber 6 is divided into a plurality of identical micro chambers, each of which is equipped with an air pressure sensor, see Figure 5In the present embodiment, when the test object undergoes rubber creep, its deformation will cause a gap to be generated between the axial outer wall of the test object and the inner wall of the loading slot, thereby enabling the reaction chamber 6 and the loading slot to be connected. By designing multiple reaction chambers 6, the deformation position of the test object can be accurately located, thus narrowing the scope of investigation and being more helpful for inspection and judgment.

[0053] By using the above structures, the elastic recovery ability of rubber products can be tested, and rubber products that have undergone rubber creep can also be monitored.

[0054] A method for detecting elasticity of a rubber product, the method using a rubber product elasticity detection device and an external negative pressure device, the method comprising the following steps:

[0055] S1: The test object is sleeved on the outer wall of the guide column 4 and the flexible pressure sensing sheet 11, and the height of the top of the measuring rod 7 is recorded;

[0056] S2: Turn on the testing machine 1, and make the driving mechanism 5 drive the constant pressure part 3 to enter the loading slot and reciprocately compress the top of the test object;

[0057] S3: After the preset number of compressions, the height of the top of the measuring rod 7 is measured to detect the recovery ability of the test object;

[0058] S4: Associating the negative pressure device with the reaction chamber 6 to make the inside of the reaction chamber 6 a negative pressure state, and using an air pressure sensor to detect the negative pressure state of the reaction chamber 6 to detect whether rubber creep occurs in the test object.

[0059] In the inspection of rubber products, especially rubber gaskets and shock absorbers that need to be compressed and restored repeatedly, the recovery stroke and recovery strength of the rubber products are the most important. Therefore, in this method, the elastic recovery ability of the test object can be judged by measuring the height or thickness of the test object. Secondly, the isolation ability of the test object can also be used to judge whether rubber creep has occurred. The most obvious manifestation of rubber creep is deformation of the rubber product.

[0060] Furthermore, in S4, it also includes:

[0061] V1: records the initial pressure value of the flexible pressure sensing sheet 11;

[0062] V2: After the rubber creep occurs, check whether the tightening force or internal stress of the test object on the flexible pressure sensing sheet 11 is relaxed.

[0063] In this method, by comparing the front and rear pressure values ​​of the flexible pressure sensing sheet 11, it is possible to determine whether the internal stress applied by the test object to the flexible pressure sensing sheet 11 is weakened, and then determine whether the test object undergoes stress relaxation synchronously after rubber creep.

[0064] Furthermore, in S1, a self-checking step is also included:

[0065] T1: Associating the negative pressure device with the reaction chamber 6, so that the inside of the reaction chamber 6 is in a negative pressure state, and using the up and down displacement of the annular limit piece 8 to put the test object in an interference fit state;

[0066] T2: The annular limiting piece 8 moves upward, releases the resistance to the top of the test object and detaches from the inner wall of the loading slot, and releases the top of the test object;

[0067] T3: Detect the negative pressure state of the reaction chamber 6. If the negative pressure state of the reaction chamber 6 remains unchanged, it is determined that the interference fit of the test object is normal, and the subsequent rubber creep test steps can be performed.

[0068] In this method, the accuracy of the detection work can be ensured by self-checking the isolation capability of the test object.

[0069] By adopting the above method, the elastic recovery ability of the rubber product can be tested in a mold, and the rubber creep can also be monitored and the deformation position can be tracked.

[0070] The standard parts used in this embodiment can be purchased directly from the market, and the non-standard structural components recorded in the specification and the drawings can also be directly processed according to the existing technical common sense without any doubt. At the same time, the connection method of each component adopts the mature conventional means in the prior art, and the machinery, parts and equipment all adopt the conventional models in the prior art, so no specific description will be given here.

[0071] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rubber product elasticity testing device, characterized in that: include: A testing machine (1), wherein the testing machine (1) is provided with a driving mechanism (5) and a bearing platform; A bottom mold (2) is locked on the bearing platform, and a loading slot is provided inside the bottom mold (2), and the loading slot is used for interference fitting the test object; A constant pressure portion (3) is fixedly mounted on the output end of the driving mechanism (5); The top of the bottom mold (2) is designed as an open channel, and the constant pressure portion (3) can enter the channel and apply axial pressure to the test object; The inner top of the bottom mold (2) is provided with a metering structure for detecting the reset height of the test object.

2. The rubber product elasticity testing device according to claim 1, characterized in that: A reaction chamber (6) is also provided inside the bottom mold (2), and the reaction chamber (6) is connected to the inner bottom of the loading groove at the circumferential edge. When the test object is interference-fitted in the loading groove, the test object isolates the connection between the reaction chamber (6) and the loading groove, and the interior of the reaction chamber (6) is negative pressure.

3. The rubber product elasticity testing device according to claim 2, characterized in that: A plurality of adaptive cylinders (9) are installed at the top of the bottom mold (2), and an annular limiting piece (8) is installed at the output end of the adaptive cylinder (9). The outer edge of the annular limiting piece (8) can slide with the inner wall of the loading groove in a piston-like manner. When driven by the adaptive cylinder (9), the bottom of the annular limiting piece (8) always contacts the top of the test object.

4. The rubber product elasticity testing device according to claim 3, characterized in that: The metering structure comprises a measuring rod (7) fixedly mounted on an annular stopper (8), the measuring rod (7) passing through the inner top of the bottom mold (2), and the outer wall of the measuring rod (7) is marked with a metering scale, the top of the measuring rod (7) is a reflective surface, and the testing machine (1) is equipped with a miniature laser rangefinder, which can measure the distance between the top of the measuring rod (7) and the laser rangefinder.

5. The rubber product elasticity testing device according to claim 2, characterized in that: A guide column (4) is fixedly mounted on the inner bottom of the loading slot, and the test object can be sleeved on the outside of the guide column (4). A guide hole is opened on the constant pressure portion (3), and the guide hole forms a guiding fit with the outer wall of the guide column (4).

6. The rubber product elasticity testing device according to claim 5, characterized in that: The outer wall of the guide column (4) near the bottom end is covered with a flexible pressure sensing sheet (11), and the flexible pressure sensing sheet (11) is composed of a flexible substrate, a conductive layer, a pressure-sensitive layer and a protective layer from the inside to the outside. The test object will be sleeved on the outer wall of the protective layer before testing, and the flexible pressure sensing sheet (11) is associated with an external digital display system.

7. The rubber product elasticity testing device according to any one of claims 2 to 6, characterized in that: The reaction chamber (6) is divided into a plurality of identical micro chambers, each of which is equipped with an air pressure sensor.

8. A method for detecting elasticity of a rubber product, the method being implemented by using the rubber product elasticity detection device as claimed in claim 6 and an external negative pressure device, characterized in that: The detection method comprises the following steps: S1: The test object is sleeved on the outer wall of the guide column (4) and the flexible pressure sensing sheet (11), and the height of the top of the measuring rod (7) is recorded; S2: Turn on the testing machine (1), so that the driving mechanism (5) drives the constant pressure part (3) to enter the loading slot and reciprocately compress the top of the test object; S3: After the preset number of compressions, the height of the top of the measuring rod (7) is measured to detect the recovery ability of the test object; S4: Associating the negative pressure device with the reaction chamber (6) so that the interior of the reaction chamber (6) is in a negative pressure state, and using an air pressure sensor to detect the negative pressure state of the reaction chamber (6) to detect whether rubber creep occurs in the test object.

9. The method for detecting elasticity of rubber products according to claim 8, characterized in that: In said S4, it also includes: V1: records the initial pressure value of the flexible pressure sensing sheet (11); V2: After the rubber creep occurs, check whether the tightening force or internal stress of the test object on the flexible pressure sensing sheet (11) is relaxed.

10. The method for detecting elasticity of rubber products according to claim 8, characterized in that: In the S1, a self-checking step is also included: T1: Associating the negative pressure device with the reaction chamber (6) so that the interior of the reaction chamber (6) is in a negative pressure state, and utilizing the up and down displacement of the annular limiting piece (8) to place the test object in an interference fit state; T2: The annular limiting piece (8) moves upward, releases the resistance to the top of the test object and detaches from the inner wall of the loading slot, and releases the top of the test object; T3: Detecting the negative pressure state of the reaction chamber (6). If the negative pressure state of the reaction chamber (6) remains unchanged, it is determined that the interference fit of the test object is normal, and the subsequent rubber creep test steps can be performed.

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