A static tire wrapping force partition linear fitting method and device

Abstract

The present application relates to the field of tire mechanical property data processing, in particular to a static tire covering force partition linear fitting method and device, wherein the static tire covering force partition linear fitting method comprises the following steps: performing covering rigidity test on the static tire, obtaining multiple groups of protrusion lifting distance and protrusion load in the load loading stage and the load unloading stage, drawing a test data scatter plot of protrusion load and protrusion displacement with the protrusion lifting distance as the abscissa and the protrusion load as the ordinate; dividing the load loading stage and the load unloading stage of the test data scatter plot according to at least two kinds of preset load intervals respectively and forming multiple partitions, and determining the covering rigidity of each partition according to the protrusion lifting distance and the protrusion load of each partition; and fitting the covering rigidity curve according to the covering rigidity of each partition. Thus, the accuracy of the static tire covering rigidity test is improved, which is conducive to subsequent characteristic analysis of the tire.

Description

Technical Field

[0001] This invention relates to the field of tire mechanical property data processing, specifically to a method and apparatus for linear fitting of static tire wrapping force zones. Background Technology

[0002] Tire wrap stiffness characteristics refer to the relationship between the bulge load and bulge displacement at the tire contact patch under specified tire pressure and vertical load conditions. It reflects the tire's ability to enclose road surface bulges (i.e., its enveloping characteristics) and is closely related to tire comfort.

[0003] Existing technologies typically only collect experimental data during the vertical load loading phase, neglecting experimental data during the vertical load unloading phase. This results in relatively limited experimental data, leading to lower experimental accuracy and hindering subsequent tire feature analysis.

[0004] Therefore, how to improve the accuracy of testing the static tire sheathing rigidity to facilitate subsequent tire characteristic analysis is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] This invention discloses a linear fitting method for static tire sheathing force partitioning to solve the technical problem of low accuracy in testing static tire sheathing rigidity in existing technologies, which makes subsequent tire feature analysis inconvenient. The method includes:

[0006] The test tire is mounted on the test rim, inflated to the preset pressure, and left to stand for the first preset time.

[0007] The assembly of the test tire and test rim is fixed to the test rigidity machine, and the test tire is brought into contact with the contact platform.

[0008] Vertical force is applied to the test tire at a first preset moving speed until each preset target load is reached, and finally the preset maximum target load is reached. After each preset target load or the preset maximum target load is reached and held for a second preset time, an upward bulge is applied at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0009] The vertical force is unloaded from the preset maximum target load to each preset target load. After each preset target load is reduced and held for a second preset duration, an upward bulge is applied at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0010] Plot a scatter plot of the test data of bulge load and bulge displacement with the distance the bulge rises as the x-axis and the load on the bulge as the y-axis.

[0011] The load loading and unloading phases of the test data scatter plot are divided into multiple partitions according to at least two preset load ranges. The covering rigidity of each partition is determined according to the distance of the bulge rise and the bulge load.

[0012] The wrapping stiffness curve is generated by fitting the wrapping stiffness of each partition;

[0013] Wherein, the load in the preset load range is less than the preset maximum target load.

[0014] In some embodiments of this application, the covering rigidity of each partition is determined based on the distance the protrusions of each partition rise and the load on the protrusions, specifically as follows:

[0015] The experimental data for each region were fitted with a single linear equation. The fitting formula was y = b0 + b1x. The values ​​of constants b0 and b1 were obtained.

[0016] Where b1 represents the rigidity of the covering.

[0017] In some embodiments of this application, the preset load range includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

[0018] In some embodiments of this application, the preset maximum target load includes 90% of the maximum load of the test tire.

[0019] In some embodiments of this application, before applying a vertical force to the test tires at a first preset moving speed until each preset target load is reached, the method further includes:

[0020] Apply a vertical force to the test tire at the first preset moving speed until the pre-test load is reached, maintain it for a third preset time, and then unload it. Repeat the pre-test a preset number of times. After the pre-test is completed, inflate the test tire to the preset air pressure.

[0021] The present invention also proposes a static tire wrapping force zoning linear fitting device, the device comprising:

[0022] The contact platform accommodates and contacts the test tire.

[0023] The loading module is used to apply vertical force to the test tire and to apply an upward bulge;

[0024] The positioning module is used to fix the test tire to the contact platform;

[0025] Controller, used for:

[0026] When receiving a test command sent by the user, the control loading module applies vertical force to the test tire at a first preset moving speed until each preset target load is reached, and finally reaches the preset maximum target load. After each preset target load or the preset maximum target load is reached and held for a second preset time, the control loading module applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0027] The control loading module unloads the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads. After each preset target load is reduced and held for the second preset duration, the control loading module applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0028] Plot a scatter plot of the test data of bulge load and bulge displacement with the distance the bulge rises as the x-axis and the load on the bulge as the y-axis.

[0029] The load loading and unloading phases of the test data scatter plot are divided into multiple partitions according to at least two preset load ranges. The covering rigidity of each partition is determined according to the distance of the bulge rise and the bulge load.

[0030] The covering stiffness curve is generated by fitting the covering stiffness of each partition;

[0031] Wherein, the load in the preset load range is less than the preset maximum target load.

[0032] In some embodiments of this application, the controller is specifically used for:

[0033] The experimental data for each region were fitted with a single linear equation. The fitting formula was y = b0 + b1x. The values ​​of constants b0 and b1 were obtained.

[0034] Where b1 represents the rigidity of the covering.

[0035] In some embodiments of this application, the preset load range includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

[0036] In some embodiments of this application, the preset maximum target load includes 90% of the maximum load of the test tire.

[0037] In some embodiments of this application, the controller is also used for:

[0038] Upon receiving a pre-test instruction from the user, the control loading module applies a vertical force to the test tire at the first preset moving speed until the pre-test load is reached. After maintaining this force for a third preset duration, the load is unloaded, and the pre-test is repeated a preset number of times.

[0039] By applying the above technical solution, a wrapping rigidity test is conducted on a static tire. Multiple sets of bulge lifting distances and bulge loads are obtained during the load loading and unloading phases. A scatter plot of the test data is plotted with the bulge lifting distance as the x-axis and the bulge load as the y-axis. The load loading and unloading phases of the test data scatter plot are divided into multiple partitions based on at least two preset load ranges. The wrapping rigidity of each partition is determined based on the bulge lifting distance and bulge load. A wrapping rigidity curve is generated by fitting the wrapping rigidity of each partition. The load in the preset load range is less than the preset maximum target load. This improves the accuracy of the static tire wrapping rigidity test and facilitates subsequent tire feature analysis. Attached Figure Description

[0040] Figure 1 A flowchart illustrating a static tire wrapping force zoning linear fitting method proposed in an embodiment of the present invention is shown.

[0041] Figure 2 A schematic diagram of a tire static wrapping rigidity test is shown in an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a static tire wrapping force zoning linear fitting device proposed in an embodiment of the present invention is shown. Detailed Implementation

[0043] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] This application provides a method for linear fitting of static tire wrapping force in different zones. By fitting the test data of the wrapping force in each zone with a univariate linear equation, the test data of the loading and unloading sections can be fitted into a smooth curve with high accuracy. This curve can then be used to calculate tire characteristic values, perform benchmark analysis, or for tire model identification. It features high accuracy, good repeatability, and high efficiency. Figure 1 As shown, it includes the following steps:

[0045] Step S101: Mount the test tire onto the test rim, inflate the test tire to a preset pressure, and leave it for a first preset time.

[0046] In this embodiment, tires with similar production dates, batches, storage environments, usage histories, and good appearance quality should be selected as test tires;

[0047] The preset pressure can be 250 kPa or 290 kPa, and those skilled in the art can adjust it according to the requirements of the experiment;

[0048] The first preset duration should be more than 24 hours, and the tire should be stored at room temperature after being pressurized. If the tire has been assembled and inflated within 24 hours, it does not need to be stored. Those skilled in the art can flexibly set the time according to the experimental requirements.

[0049] When mounting the tire onto the rim, ensure that there is no damage, defects, or impurities on the contact surface between the tire and the rim: do not over-lubricate, use a suitable adapter if necessary, and ensure that the steering center position remains unchanged.

[0050] Step S102: Fix the assembly of the test tire and the test rim onto the test rigidity machine and make the test tire contact the contact platform.

[0051] In this embodiment, the test rigidity tester is used to perform longitudinal rigidity tests on the test tire. During the test, the test tire contacts the contact platform. The contact platform can completely accommodate the entire contact portion of the tire and has sufficient roughness. The contact platform has sufficient stroke to meet the test requirements. The contact platform and its supporting structure have sufficient rigidity so that the contact platform does not undergo longitudinal, longitudinal, or bending deformation when a vertical force is applied to the tire.

[0052] Step S103: Apply vertical force to the test tire at a first preset moving speed until each preset target load is reached, and finally reach the preset maximum target load. After each preset target load or the preset maximum target load is reached and held for a second preset time, apply an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0053] In this embodiment, multiple preset target loads are pre-set, such as Figure 2As shown, a vertical force Fz1 is applied to the test tire at a first preset moving speed until each preset target load is reached, and finally the preset maximum target load is reached. After each preset target load or preset maximum target load is reached, the load is maintained for a second preset time. At the contact point between the test tire and the test rigidity machine, an upward bulge is applied at a second preset moving speed until the preset bulge load Fz2 is reached. The distance of the bulge is S. Thus, the distance of the bulge and the bulge load Fz2 corresponding to each preset target load during the load loading stage can be obtained.

[0054] Optionally, the first preset moving speed is within 10000 N / min, the second preset duration is 1 min, and the second preset moving speed is within 20 mm / min. Those skilled in the art can flexibly set different first preset moving speeds, second preset durations, and second preset moving speeds according to actual needs.

[0055] To improve the accuracy of test data, in some embodiments of this application, before applying vertical force to the test tires at a first preset moving speed until each preset target load is reached, the method further includes:

[0056] Apply a vertical force to the test tire at the first preset moving speed until the pre-test load is reached, maintain it for a third preset time, and then unload it. Repeat the pre-test a preset number of times. After the pre-test is completed, inflate the test tire to the preset air pressure.

[0057] In this embodiment, before the formal longitudinal rigidity test of the test tire is carried out, a preset number of pre-tests are performed to ensure that there are no problems with the test tire and the test rigidity tester. Then, the test tire is inflated to the preset pressure for the formal test.

[0058] Optionally, the pre-test load is 90% of the maximum load of the test tire, and the third preset duration can be 5 seconds.

[0059] Step S104: Unload the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads respectively. After each preset target load is reduced and held for the second preset duration, an upward bulge is applied at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0060] In this embodiment, as Figure 2As shown, after completing the load loading stage test, the load unloading stage begins. The vertical force Fz1 is unloaded from the preset maximum target load to each preset target load. After each preset target load is reached, the load is maintained for a second preset time. At the contact point between the test tire and the test rigidity machine, an upward bulge is applied at a second preset moving speed until a preset bulge load Fz2 is reached. The distance of the bulge is S. Thus, the distances of the multiple bulges corresponding to each preset target load during the load unloading stage and the bulge load Fz2 can be obtained.

[0061] Step S105: Plot a scatter plot of the test data of the bulge load and bulge displacement with the distance the bulge rises as the abscissa and the load of the bulge as the ordinate.

[0062] In this embodiment, based on the multiple sets of bulge lifting distances and bulge loads obtained in steps S103 and S104, a scatter plot of test data of bulge load and bulge displacement is drawn with the bulge load as the vertical axis.

[0063] Step S106: Divide the load loading stage and load unloading stage of the test data scatter plot into multiple partitions according to at least two preset load ranges, and determine the covering rigidity of each partition according to the distance of the bulge rise and the bulge load.

[0064] In this embodiment, the load of the preset load range is less than the preset maximum target load. The load loading stage of the test data scatter plot is divided into multiple partitions according to the preset load range, and the load unloading stage of the test data scatter plot is divided into multiple partitions according to the preset load range. Then, the covering rigidity of each partition is determined according to the test data of each partition.

[0065] To accurately determine the longitudinal rigidity of each partition, in some embodiments of this application, the covering rigidity of each partition is determined based on the distance the protrusions rise and the load on the protrusions, specifically as follows:

[0066] The experimental data for each region were fitted with a single linear equation. The fitting formula was y = b0 + b1x. The values ​​of constants b0 and b1 were obtained.

[0067] Where b1 represents the rigidity of the covering.

[0068] It should be noted that the above embodiments are only one specific implementation scheme proposed in this application, and other methods of determining the covering rigidity of each partition based on the distance of the raised protrusions and the load of the protrusions are all within the protection scope of this application.

[0069] Step S107: Generate a covering stiffness curve based on the covering stiffness fitting of each partition;

[0070] In this embodiment, a smooth wrapping rigidity curve is generated by fitting the wrapping rigidity of each zone. This wrapping rigidity curve can be used to calculate tire characteristic values, perform benchmark analysis, or for tire model identification.

[0071] Optionally, in some embodiments of this application, the preset load range includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

[0072] Understandably, the load loading phase of the scatter plot of the test data is divided into three zones based on 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load; the load unloading phase of the scatter plot of the test data is also divided into three zones based on 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load, thus forming a total of six zones.

[0073] Optionally, in some embodiments of this application, the preset maximum target load includes 90% of the maximum load of the test tire.

[0074] By applying the above technical solution, a wrapping rigidity test is conducted on a static tire. Multiple sets of bulge lifting distances and bulge loads are obtained during the load loading and unloading phases. A scatter plot of the test data is plotted with the bulge lifting distance as the x-axis and the bulge load as the y-axis. The load loading and unloading phases of the test data scatter plot are divided into multiple partitions based on at least two preset load ranges. The wrapping rigidity of each partition is determined based on the bulge lifting distance and bulge load. A wrapping rigidity curve is generated by fitting the wrapping rigidity of each partition. The load in the preset load range is less than the preset maximum target load. This improves the accuracy of the static tire wrapping rigidity test and facilitates subsequent tire feature analysis.

[0075] This application also proposes a static tire wrapping force zoning linear fitting device, such as... Figure 3 As shown, the device includes:

[0076] Contact platform 10, which accommodates and contacts the test tire;

[0077] Loading module 20 is used to apply a vertical force to the test tire and to apply an upward protrusion;

[0078] Positioning module 30 is used to fix the test tire on the contact platform;

[0079] Controller 40, used for:

[0080] When receiving a test command sent by the user, the control loading module 20 applies vertical force to the test tire at a first preset moving speed until each preset target load is reached, and finally reaches the preset maximum target load. After each preset target load or the preset maximum target load is reached and held for a second preset time, the control loading module 20 applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0081] The control loading module 20 unloads the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads. After each preset target load is reduced and held for the second preset duration, the control loading module 20 applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached.

[0082] Plot a scatter plot of the test data of bulge load and bulge displacement with the distance the bulge rises as the x-axis and the load on the bulge as the y-axis.

[0083] The load loading and unloading phases of the test data scatter plot are divided into multiple partitions according to at least two preset load ranges. The covering rigidity of each partition is determined according to the distance of the bulge rise and the bulge load.

[0084] The covering stiffness curve is generated by fitting the covering stiffness of each partition;

[0085] Wherein, the load in the preset load range is less than the preset maximum target load.

[0086] In the specific application scenario of this application, the controller 40 is specifically used for:

[0087] The experimental data for each region were fitted with a single linear equation. The fitting formula was y = b0 + b1x. The values ​​of constants b0 and b1 were obtained.

[0088] Where b1 represents the rigidity of the covering.

[0089] In the specific application scenario of this application, the preset load range includes 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

[0090] In the specific application scenario of this application, the preset maximum target load includes 90% of the maximum load of the test tire.

[0091] In the specific application scenario of this application, the controller 40 is also used for:

[0092] Upon receiving a pre-test instruction from the user, the control loading module 20 applies a vertical force to the test tire at the first preset moving speed until the pre-test load is reached, holds for a third preset duration, and then unloads the load. This process is repeated a preset number of times for the pre-test.

[0093] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A method for linear fitting of static tire wrapping force in different zones, characterized in that, The method includes: The test tire is mounted on the test rim, inflated to a preset pressure, and left to stand for a first preset time. The assembly of the test tire and the test rim is fixed to the test rigidity machine, and the test tire is brought into contact with the contact platform; Vertical force is applied to the test tire at a first preset moving speed until each preset target load is reached, and finally the preset maximum target load is reached. After each preset target load or the preset maximum target load is reached and held for a preset holding time, an upward bulge is applied at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached. The vertical force is unloaded from the preset maximum target load to each preset target load. After each preset target load is reduced and held for a preset holding time, an upward bulge is applied at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached. Plot a scatter plot of the test data of bulge load and bulge displacement with the distance the bulge rises as the x-axis and the load on the bulge as the y-axis. The load loading and unloading phases of the test data scatter plot are divided into multiple partitions according to at least two preset load ranges. The covering rigidity of each partition is determined according to the distance of the bulge rise and the bulge load. The wrapping stiffness curve is generated by fitting the wrapping stiffness of each partition; Wherein, the load in the preset load range is less than the preset maximum target load.

2. The method according to claim 1, characterized in that, The covering rigidity of each zone is determined based on the distance the bulges rise and the bulge load, specifically as follows: The experimental data for each region were fitted with a separate univariate linear equation. The fitting formula was set as y = b0 + b1 x. The values ​​of constants b0 and b1 were obtained. Where x represents the distance the bulge rises, y represents the load on the bulge, and the values ​​of constants b0 and b1 are obtained, where b1 is the covering rigidity.

3. The method according to claim 1, characterized in that, The preset load ranges include 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

4. The method according to claim 1, characterized in that, The preset maximum target load includes 90% of the maximum load of the test tire.

5. The method according to claim 1, characterized in that, Before applying vertical forces to the test tires at a first preset moving speed until each preset target load is reached, the method further includes: Apply a vertical force to the test tire at the first preset moving speed until the pre-test load is reached, maintain it for a third preset time, and then unload it. Repeat the pre-test a preset number of times. After the pre-test is completed, inflate the test tire to the preset air pressure.

6. A static tire wrapping force zoning linear fitting device, characterized in that, The device includes: The contact platform accommodates and contacts the test tire. The loading module is used to apply vertical force to the test tire and to apply an upward bulge; The positioning module is used to fix the test tire to the contact platform; Controller, used for: When receiving a test command sent by the user, the control loading module applies vertical force to the test tire at a first preset moving speed until each preset target load is reached, and finally reaches the preset maximum target load. After each preset target load or the preset maximum target load is reached and held for a preset holding time, the control loading module applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached. The control loading module unloads the vertical force on the test tire from the preset maximum target load until it is reduced to each of the preset target loads. After each preset target load is reduced and held for the preset holding time, the control loading module applies an upward bulge at the contact point between the test tire and the test rigidity machine at a second preset moving speed until a preset bulge load is reached. Plot a scatter plot of the test data of bulge load and bulge displacement with the distance the bulge rises as the x-axis and the load on the bulge as the y-axis. The load loading and unloading phases of the test data scatter plot are divided into multiple partitions according to at least two preset load ranges. The covering rigidity of each partition is determined according to the distance of the bulge rise and the bulge load. The wrapping stiffness curve is generated by fitting the wrapping stiffness of each partition; Wherein, the load in the preset load range is less than the preset maximum target load.

7. The apparatus according to claim 6, characterized in that, The controller is specifically used for: The experimental data for each region were fitted with a separate univariate linear equation. The fitting formula was set as y = b0 + b1 x. The values ​​of constants b0 and b1 were obtained. Where x represents the distance the bulge rises, y represents the load on the bulge, and the values ​​of constants b0 and b1 are obtained, where b1 is the covering rigidity.

8. The apparatus according to claim 6, characterized in that, The preset load ranges include 0%-30%, 30%-60%, and 60%-90% of the preset maximum target load.

9. The apparatus according to claim 6, characterized in that, The preset maximum target load includes 90% of the maximum load of the test tire.

10. The apparatus according to claim 6, characterized in that, The controller is also used for: Upon receiving a pre-test instruction from the user, the control loading module applies a vertical force to the test tire at the first preset moving speed until the pre-test load is reached. After maintaining this force for a third preset duration, the load is unloaded, and the pre-test is repeated a preset number of times.

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