A method, system, device and storage medium for determining a post-vulcanization inflation delay time for a tire

Abstract

The present application belongs to the technical field of tire manufacturing process control, and particularly relates to a method, system, device and storage medium for determining post-inflation delay time of a tire after vulcanization. The method comprises setting multiple post-inflation delay time gradients, and performing post-inflation treatment on tires corresponding to each delay time; obtaining a wire bead offset amount through X-ray detection and establishing a structure feasible region; performing RFV, RFH1, LFV, CON and other uniform performance tests on tires in the structure feasible region; normalizing structure parameters and uniform parameters and constructing a comprehensive evaluation model; and determining an optimal post-inflation delay time window according to the evaluation results and fitting trends. The present application can inhibit deformation of a wire bead structure while promoting release of a carcass thermal stress, and improve uniform performance of a tire and consistency of finished products.

Description

Technical Field

[0001] This invention belongs to the field of tire manufacturing process control technology, and particularly relates to a method, system, equipment and storage medium for determining the post-inflation delay time after tire vulcanization. Background Technology

[0002] In tire manufacturing, vulcanization is a crucial process that determines tire dimensional stability, carcass structural consistency, and performance. After being heated, pressurized, and molded in the vulcanizing machine, the tire typically needs to be removed from the vulcanizing mold by a tire removal robot or transfer mechanism and sent to the post-inflation station for shaping and cooling. The purpose of the post-inflation process is to cool the high-temperature vulcanized tire under certain internal pressure and rim support conditions, thereby reducing the impact of uneven carcass shrinkage, deformation, and stress release on the uniformity of the finished tire.

[0003] Because there is usually a certain transfer and dwell time between the opening of the vulcanizing machine and the entry of the tire into the post-inflation station, this time can be called the post-inflation delay time. Although this delay time objectively exists in the production cycle, it is currently set according to the equipment operation cycle, operating experience, or fixed process time in existing production, lacking a quantitative method for determining different tire specifications, different vulcanization conditions, and different structural sensitivities. For large-specification tires or tires with sensitive bead structures, the tire is still in a high-temperature state after vulcanization, the rubber material modulus is low, and the internal thermal stress of the tire carcass has not been fully released. At this time, the tire is prone to structural response differences due to its own weight, robotic gripping, transfer support, and dwell state before post-inflation, which in turn affects the tire's final uniform dynamic performance.

[0004] It is recognized in the prior art that the temperature, inflation pressure, and cooling method before and after vulcanization affect tire performance. For example, US Patent 4420453A discloses a method for manufacturing a polyester cord radial tire, which proposes delaying the vulcanization and inflation of the tire after it has been removed from the mold for a certain period of time, and measuring the time required for the internal temperature of the tire to drop to a predetermined temperature using a temperature probe, in order to improve the dimensional stability of the polyester cord tire during the inflation process. This approach demonstrates that the delay time between demolding and inflation affects the internal material state of the tire, but it mainly relies on the cord temperature to set the delay time and does not establish an evaluation method for the coupling relationship between steel wire bead position displacement, bead structure deformation, and tire uniformity performance.

[0005] For example, Chinese patent application CN103158220A discloses a rear-inflation device and a cooling method for vulcanized tires. It involves installing a sprayer and exhaust port on the rim of the rear-inflation device to spray a cooling medium into the tire and exhaust the air, thereby cooling the ply layer in a shorter time and suppressing the deterioration of RFV and RRO caused by thermal shrinkage of the ply layer. This solution focuses on the cooling efficiency during the rear-inflation process and the structural improvement of the rear-inflation device, demonstrating the correlation between the cooling state after vulcanization and uniformity indicators such as RFV and RRO. However, it does not address the issue of determining the pre-inflation delay time, nor does it incorporate wire bead offset, taper, radial force variation, lateral force variation, and harmonic indicators into the same comprehensive evaluation system.

[0006] In addition, existing tire post-curing inflation technologies also include constrained post-inflation methods. This involves controlling the tread, bead position, and internal pressure while the tire is still at a high temperature after demolding to improve tire uniformity, contact patch shape, and wear performance. While this approach improves the post-curing state from an equipment constraint perspective, its focus is on mechanical constraints and pressure maintenance during post-inflation, rather than establishing a process window for the delayed stage between mold opening and the initial setting pressure of post-inflation.

[0007] Therefore, although existing technologies address post-inflation delay, post-inflation cooling, and tire uniformity improvement respectively, they still have the following shortcomings: First, the post-inflation delay time is usually judged based on experience or temperature drop, lacking a quantitative evaluation method that simultaneously considers the stability of the bead structure and uniform dynamic performance; Second, existing solutions focus more on the post-inflation process itself, paying insufficient attention to the risk of bead offset under the combined effects of thermal stress release, self-weight, and mechanical transfer loads during the pre-inflation period of the vulcanized high-temperature tire; Third, existing technologies fail to incorporate bead offset along with uniform dynamic parameters such as RFV, RFH1, LFV, and CON into a comprehensive evaluation model, making it difficult to determine a reasonable balance range between "insufficient thermal stress release due to excessively short delay time" and "increased risk of bead structure deformation due to excessively long delay time."

[0008] Based on the above, it is necessary to propose a method for determining the post-inflation delay time after tire vulcanization. By setting multiple post-inflation delay time gradients, the positional offset of the steel wire ring and the uniform dynamic performance parameters of the tire are detected respectively. A comprehensive judgment model combining structural constraints and performance evaluation is established to determine the optimal post-inflation delay time window that can both suppress the deformation of the steel wire ring structure and improve the uniform dynamic performance of the tire. Summary of the Invention

[0009] The technical objective of this invention is to provide a method for determining the post-inflation delay time after tire vulcanization. By simultaneously introducing the stability test of the bead structure and the evaluation of tire uniform dynamic performance, the delay time from the opening of the vulcanizing machine to the post-inflation shaping is quantitatively screened to determine the optimal post-inflation delay time window that balances the preservation of bead structure deformation and optimization of uniform dynamic performance. This overcomes the problem that the post-inflation delay time in existing production mainly relies on experience to set and is difficult to adapt to different tire specifications and different vulcanization conditions.

[0010] Firstly, in order to achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0011] A method for determining the post-inflation delay time after tire vulcanization, the method comprising the following steps:

[0012] S1. Select multiple vulcanized tires of the same specification, under the same vulcanization conditions, the same transfer method, and the same post-inflation station conditions as test samples, and set multiple different post-inflation delay times. The post-inflation delay time The time between the completion of mold opening in the tire vulcanizing machine and the tire reaching the initial shaping pressure at the rear inflation station;

[0013] S2, according to each The vulcanized tires were transferred, held, and then inflated. After the inflated tires cooled down, the steel wire bead structure was inspected, and the inflated tire delay time was recorded. Corresponding wire coil offset ;

[0014] S3, according to Offset threshold of the preset steel wire coil Establish the structurally feasible region ;

[0015] S4, for those in each within The corresponding tires were subjected to uniform dynamic performance testing to obtain at least the radial force variation. First-order radial force harmonics Lateral force changes and taper The uniform dynamic parameters;

[0016] S5, regarding the uniformity parameters and Normalization was performed to obtain each Corresponding moving average normalized index and the normalized index of wire coil ;

[0017] S6, based on , And corresponding weights, to establish a comprehensive evaluation function. ;

[0018] S7, to each after and By performing continuous function fitting, the delay time-comprehensive evaluation trend curve is obtained. Under the condition that the steel wire ring structure does not deform, the time interval with the minimum comprehensive evaluation value or within the optimal tolerance range is selected to determine the optimal after-inflation delay time window after tire vulcanization. .

[0019] As a further improvement, in step S1, the plurality of post-inflation delay times Distributed within the range of 15s to 180s, with the interval between two adjacent post-inflation delay times ranging from 10s to 45s, and each post-inflation delay time The number of test tires should be no less than 3.

[0020] As a further improvement, in step S2, the steel wire ring structure detection is performed using X-ray detection. At least eight detection positions are selected along the tire circumference. At each detection position, edge feature points of the steel wire ring are identified, and the offset of the steel wire ring is obtained through pixel conversion. The offset of the wire coil Calculate using the following formula:

[0021] ;

[0022] In the formula, Post-inflation delay time The corresponding wire loop offset; This is a conversion factor for pixel size; Post-inflation delay time The corresponding tire is at the The first circumferential detection position, the first Image coordinates of feature points on the edge of the steel wire loop; The image coordinates of the same detection location and the same steel wire bead edge feature points in the reference tire or design reference; This is the coordinate distance operator.

[0023] As a further improvement, in step S3, the structurally feasible region :

[0024] ;

[0025] In the formula, For structurally feasible regions; For the first Post-inflation delay time; Post-inflation delay time The corresponding wire loop offset; The allowable wire loop offset threshold; This is the structural deformation judgment value. When the tire does not exhibit localized warping, misalignment, or discontinuity interruption of the steel wire bead, ;

[0026] Preferably, the structural deformation determination value Determine using the following formula:

[0027] In the formula, This is the value for determining structural deformation. Post-inflation delay time The corresponding wire loop offset; This refers to the allowable offset threshold for the wire coil; This represents the difference in offset between the steel wire rings on both sides of the same tire. The allowable threshold for the difference in offset between the two steel wire loops; when At that time, the corresponding post-inflation delay time will be adjusted. From the structural feasible domain Remove from the list.

[0028] As a further improvement, in step S5, the dynamic normalization index... Calculate using the following formula:

[0029] ;

[0030] In the formula, For uniform dynamic parameters Post-inflation delay time The normalized value below; For uniform dynamic parameters Post-inflation delay time The sample mean; For uniform dynamic parameters In the structurally feasible region The maximum sample mean within the range; For uniform dynamic parameters In the structurally feasible region The minimum sample mean within; To prevent the correction factor from being zero;

[0031] And / or, in step S5, the normalized index of the wire coil Calculate using the following formula:

[0032] ;

[0033] In the formula, Post-inflation delay time The corresponding normalized index of the wire coil; Post-inflation delay time The corresponding wire loop offset; For structurally feasible regions The maximum value of the inner wire ring offset; For structurally feasible regions Minimum offset of the inner wire ring; To prevent the correction factor from being zero in the denominator.

[0034] As a further improvement, in step S6, the comprehensive evaluation function is:

[0035] ;

[0036] In the formula, Post-inflation delay time The corresponding comprehensive evaluation value; For the reason , , and The set of uniform motion parameters constituted; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters The weights; For uniform dynamic parameters Post-inflation delay time The normalized value below; This is the weight of the wire coil offset. For the offset of the wire coil Post-inflation delay time The normalized value below;

[0037] Preferably, the averaging parameter weight The values ​​are determined based on the relative changes of each uniform dynamic parameter under different post-inflation delay times, and calculated according to the following formula:

[0038] ;

[0039] In the formula, For uniform dynamic parameters The weights; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters In the structurally feasible region The relative range of change within; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters In the structurally feasible region The relative range of change within; The priority coefficient for the offset of the wire coil; For the offset of the wire loop within the structurally feasible region The relative range of change within;

[0040] Further preferred, the relative change range Calculate using the following formula:

[0041] ;

[0042] In the formula, For uniform dynamic parameters The relative magnitude of change; For uniform dynamic parameters In the structurally feasible region The maximum sample mean within the range; For uniform dynamic parameters In the structurally feasible region The minimum sample mean within; To prevent the correction factor from being zero in the denominator.

[0043] As a further improvement, in step S7, the optimal post-inflation delay time window Determine using the following formula:

[0044] ;

[0045] In the formula, To achieve the optimal post-inflation delay time window; The continuous post-inflation delay time is a variable; The offset of the wire loop varies with the continuous post-inflation delay time. A changing fitted function; This refers to the allowable offset threshold for the wire coil; The comprehensive evaluation value varies with the continuous post-inflation delay time variable. A changing fitted function; For structurally feasible regions The minimum value of the overall evaluation value of the inner fit; This is the window tolerance coefficient that allows deviations from the minimum comprehensive evaluation value;

[0046] And / or, in step S7, the continuous function fitting includes at least one of quadratic polynomial fitting, cubic polynomial fitting, piecewise polynomial fitting, exponential fitting, or locally weighted regression fitting; when the minimum point of the fitted comprehensive evaluation value is close to the structurally feasible region. When the upper boundary is reached, the wire loop offset threshold is used. The corresponding post-inflation delay time is used as the optimal post-inflation delay time window. The upper limit;

[0047] Preferably, after determining the optimal post-inflation delay time window Then, the optimal post-inflation delay time window is... This serves as the process control parameter for the tire unloading robot, tire transfer device, or post-inflation station controller in the vulcanizing machine; and it periodically collects data from tires of the same specification during mass production. , , , and wire coil offset When any parameter is relative to the determined optimal post-inflation delay time window If the baseline value exceeds the threshold and drifts, steps S1 to S7 are re-executed to update the optimal post-inflation delay time window. .

[0048] Secondly, the present invention also provides a system for implementing the method, which is jointly implemented by a production control system, a post-inflation execution system, a structural detection system, a uniform dynamic performance detection system, and an evaluation modeling system.

[0049] The production control system is used to record the opening time of the vulcanizing machine, the movement time of the tire unloading robot, the moment the tire leaves the mold, the moment the tire enters the post-inflation station, and the moment the initial shaping pressure is reached. It also controls the post-inflation delay time of different sample tires according to the test plan.

[0050] The rear inflation system includes a tire removal robot, a tire transfer device, a rear inflation rim, inflation lines, a pressure control valve, and a cooling control unit. This system is used to complete tire transfer within a set rear inflation delay time and to inflate, shape, and cool the tire at the rear inflation station.

[0051] The structural inspection system is preferably an X-ray inspection system, which includes an X-ray imaging device, a tire positioning mechanism, an image acquisition module, and an image processing module. This system is used to acquire images of the wire loop at different circumferential positions, identify feature points on the edge of the wire loop, and obtain the offset of the wire loop through pixel conversion.

[0052] The uniform dynamic performance testing system is used to test the uniform dynamic parameters such as RFV, RFH1, LFV, and CON of sample tires with different delay times;

[0053] The evaluation modeling system receives the offset of the wire ring and the uniform dynamic parameters, normalizes the indicators of different dimensions, calculates the weight coefficients and comprehensive evaluation values, and obtains the delay time-comprehensive evaluation trend curve through continuous function fitting, and finally outputs the optimal post-inflation delay time window.

[0054] Thirdly, the present invention also provides an electronic device, including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the method described above.

[0055] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described thereon.

[0056] The technical advantages of this invention are as follows: By setting multiple post-inflation delay time gradients and conducting steel wire offset detection and uniform dynamic performance tests on tires under different delay times, the influence of delay time on the stability of the bead structure and the uniform dynamic performance of the tire can be obtained; by using the steel wire offset as a structural constraint, the delay time point at which the bead deformation risk is caused by the tire remaining in a high-temperature, low-modulus state for a long time and being subjected to its own weight or the stretching action of a robotic arm can be eliminated; by incorporating uniform dynamic parameters such as radial force change, lateral force change, taper, and first-order radial force harmonics into the comprehensive evaluation model, the process deviation caused by judging based on a single indicator can be avoided, ensuring that the determined delay time is both conducive to the release of internal thermal stress after vulcanization and does not cause steel wire offset due to excessive delay. Therefore, this invention can achieve coordinated control of structural stability and uniform dynamic performance within a short time window before post-inflation, reduce fluctuations in uniform dynamic indicators such as RFV, CON, LFV and RFH1, improve the consistency of finished tires, reduce poor uniform dynamic performance and abnormal bead structure caused by improper post-inflation cycle settings, and provide quantifiable process basis for cycle control of vulcanizing machine tire unloading robots, tire transfer mechanisms and post-inflation stations. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of the overall process for determining the post-inflation delay time after tire vulcanization according to the present invention.

[0058] Figure 2 This is a schematic diagram of the post-inflation delay time gradient setting and sample grouping in this invention.

[0059] Figure 3 This is a schematic diagram of the wire loop position detection based on X-ray images according to the present invention.

[0060] Figure 4 This is a schematic diagram illustrating the determination of the feasible region for the wire coil structure of the present invention.

[0061] Figure 5 This is a schematic diagram of the tire dynamic performance test process of the present invention.

[0062] Figure 6 This is a schematic diagram illustrating the normalization process of the uniform dynamic parameters and wire coil offset in this invention.

[0063] Figure 7 This is a schematic diagram illustrating the construction of the comprehensive evaluation model of this invention.

[0064] Figure 8 This is a graph showing the trend curve of the delay time-comprehensive evaluation and the determination of the optimal time window for this invention.

[0065] Figure 9 This is a schematic diagram illustrating the feedback of the optimal post-inflation delay time window to the production control system according to the present invention.

[0066] Figure 10 This is a graph showing the trend of changes in wire ring offset, uniform dynamic parameters, and comprehensive evaluation value corresponding to different post-inflation delay times in embodiments of the present invention.

[0067] Figure 11 The graph shows the variation of wire coil offset under different post-inflation delay times.

[0068] Figure 12 A comparison chart of the overall evaluation scores under different post-inflation delay times.

[0069] Figure 13 This is a diagram showing the coupling relationship between the post-inflation delay time and the thermal stress release and the risk of wire ring deformation. Detailed Implementation

[0070] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be understood that the following embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention. Without departing from the technical concept of the present invention, those skilled in the art can make adaptive adjustments to the specific parameters according to tire specifications, vulcanizing equipment model, post-inflation station structure, testing equipment accuracy, and production cycle.

[0071] I. Terminology Explanation

[0072] In this embodiment, the "post-inflation delay time" refers to the time between the tire being removed from the vulcanizing mold after the tire vulcanizing machine has opened and undergoing processes such as tire removal, transfer, and rest, until the tire reaches the initial shaping pressure at the post-inflation station. This time is different from the post-inflation pressure holding time and the post-inflation cooling time; it belongs to the transitional process parameters of the vulcanized tire before it enters the post-inflation shaping stage.

[0073] The term "initial shaping pressure" refers to the pressure value at which the internal pressure of the tire rises to a level that allows the bead, sidewall, and crown to be stably supported after the tire enters the post-inflation station. This pressure can be a certain percentage of the pressure set in the post-inflation process, or it can be the effective initial pressure for post-inflation defined in the process document.

[0074] The term "wire bead offset" refers to the spatial deviation of the actual position of the wire bead relative to a reference position after the vulcanized tire has undergone different post-inflation delay times. The reference position can be derived from design references, standard sample tires, zero-delay reference tires, or historical sample tires that have passed process verification. The wire bead offset can include radial offset, axial offset, or a combined offset of radial and axial offsets.

[0075] The term "structurally feasible region" refers to the set of post-inflation delay times in which the positional deviation of the bead does not exceed the allowable threshold, and no structural anomalies such as local warping, misalignment, skewness, or discontinuity interruption of the bead occur. The structurally feasible region is used to exclude delay times that, while exhibiting good uniform dynamics, pose a risk to bead structure.

[0076] The term "uniform dynamic performance" refers to the performance indicators reflecting the mechanical uniformity of a tire when it is rotated on a uniformity testing device and subjected to a specified load, specified inflation pressure, and specified testing speed. In this embodiment, uniform dynamic performance includes at least radial force variation (RFV), first-order radial force harmonic (RFH1), lateral force variation (LFV), and taper (CON). Depending on the actual testing conditions, it may further include radial runout, lateral runout, second-order harmonics, third-order harmonics, or other uniformity indicators.

[0077] The so-called "comprehensive evaluation value" refers to a cost-based evaluation index calculated by normalizing the structural parameters and dynamic performance parameters of the steel wire ring and then applying predetermined weights. The smaller the comprehensive evaluation value, the better the overall performance of tire structural stability and dynamic performance corresponding to that post-inflation delay time.

[0078] The term "optimal post-inflation delay time window" refers to the post-inflation delay time interval that minimizes the overall evaluation value or keeps it within the allowable tolerance range, provided that the wire coil structure does not undergo abnormal deformation. This time window can be an interval near a single point in time or a continuous time range that meets the requirements for production cycle fluctuations.

[0079] II. System Structure

[0080] Combination Figure 1 and Figure 9 The method of the present invention can be implemented by a production control system, a post-inflation execution system, a structural detection system, a dynamic performance detection system, and an evaluation modeling system.

[0081] The production control system records the opening time of the vulcanizing machine, the movement time of the tire unloading robot, the moment the tire leaves the mold, the moment the tire enters the post-inflation station, and the moment the initial shaping pressure is reached. It also controls the post-inflation delay time for different sample tires according to the test plan. The production control system can be a vulcanizing machine PLC control system, a MES system, a post-inflation equipment controller, or a separate data acquisition and control terminal.

[0082] The rear inflation system includes a tire removal robot, a tire transfer device, a rear inflation rim, inflation lines, a pressure control valve, and a cooling control unit. This system is used to complete tire transfer within a set rear inflation delay time and to inflate, shape, and cool the tire at the rear inflation station. To ensure comparability of data for different delay times, the rear inflation pressure, holding time, cooling medium conditions, rim specifications, and tire mounting posture should be kept as consistent as possible.

[0083] The structural inspection system is preferably an X-ray inspection system, which includes an X-ray imaging device, a tire alignment mechanism, an image acquisition module, and an image processing module. This system is used to acquire images of the wire loop at different circumferential positions, identify feature points on the wire loop's edge, and obtain the wire loop's offset through pixel conversion. For applications requiring high inspection accuracy, the X-ray inspection results can be calibrated using laser contour detection, industrial CT, or an image calibration plate.

[0084] The uniform dynamic performance testing system is used to test the uniform dynamic parameters such as RFV, RFH1, LFV, and CON of tire samples with different delay times. To improve data reliability, uniform dynamic performance testing should be performed on the same testing equipment or on testing equipment that has undergone consistency calibration, and the test pressure, test load, test speed, and tire alignment method should be kept as consistent as possible.

[0085] The evaluation modeling system receives the wire coil offset and uniform dynamic parameters, normalizes indices of different dimensions, calculates weighting coefficients and comprehensive evaluation values, and obtains the delay time-comprehensive evaluation trend curve through continuous function fitting. Finally, it outputs the optimal post-inflation delay time window. The evaluation modeling system can be installed on the industrial control computer at the production site or on the enterprise's quality data platform.

[0086] III. Specific Technical Route of the Method

[0087] like Figure 1 As shown, the method of this invention generally includes steps such as sample selection and time gradient setting, inflation treatment after gradient implementation, wire ring structure detection, establishment of feasible structural domain, dynamic performance testing, index normalization, comprehensive evaluation modeling, trend fitting, and output of the optimal time window. Among these, the establishment of the feasible domain of the wire ring structure, the construction of the comprehensive evaluation model, and the determination of the optimal time window fitting are the key steps that distinguish this invention from empirically setting the inflation delay time.

[0088] (I) S1. Sample selection and post-inflation delay time gradient setting

[0089] Combination Figure 2 First, tires of the same specification, structure, formulation system, vulcanization conditions, or production batch are selected as test samples. To reduce the impact of material batch differences, vulcanization temperature differences, and mold differences on the results, preferably, the test samples come from the same vulcanizing machine or a vulcanizing machine of the same model that has been verified for consistency, and the same vulcanization temperature, vulcanization pressure, vulcanization time, and post-inflation station conditions are used.

[0090] The post-inflation delay time can be set to multiple gradients, such as 30s, 60s, 90s, and 120s, or multiple gradients within the range of 15s to 180s depending on the equipment's cycle time capability, with adjacent time intervals ranging from 10s to 45s. For production lines with large-size tires, high bead rigidity, or long robotic gripping times, the time interval can be appropriately reduced to more accurately identify the critical range where structural risks in the bead ring begin to appear. For small-size tires or production conditions with stable cycle times, a wider time interval can be used for initial screening, followed by secondary, more intensive testing near the initial optimal range.

[0091] To ensure statistical reliability, the number of samples corresponding to each post-inflation delay time should be no less than 3, preferably more than 5. Each sample should record the corresponding mold number, vulcanizing machine number, mold opening time, demolding time, post-inflation start time, initial setting pressure reached time, post-inflation pressure, post-inflation cooling time, and testing equipment number. These data can be used to eliminate obviously abnormal samples, ensuring the consistency of the data used in the subsequent comprehensive evaluation model.

[0092] The purpose of this step is to transform the post-inflation delay time, which was originally determined by production experience, into a measurable, comparable, and modelable experimental variable, providing a data foundation for subsequent structural evaluation and dynamic performance assessment. Compared to simply setting the post-inflation delay time according to the shortest equipment cycle time or a fixed empirical time, this step can reflect the differences in the impact of different delay times on the release of thermal stress, external force, and structural stability of the vulcanized tire.

[0093] (ii) S2. Perform post-inflation treatment according to different delay times.

[0094] During each post-inflation delay period, the vulcanized tire is removed from the vulcanizing machine by a tire unloading robot after the mold is opened, and enters the post-inflation station according to the set time. When the tire reaches the initial shaping pressure in the post-inflation station, the moment is recorded, and the actual post-inflation delay time is calculated by the production control system.

[0095] The actual post-inflation delay time can be expressed as:

[0096] ;

[0097] In the formula, For the first The first sample or the first The actual post-inflation delay time corresponding to each time gradient; This refers to the moment when the tire reaches its initial shaping pressure at the rear inflation station; This is the reference moment when the vulcanizing machine completes mold opening or the tire leaves the vulcanizing mold.

[0098] In this step, it is preferable to control the error of the post-inflation delay time within a set range, for example, no more than 3 to 5 seconds. When the actual delay time deviates significantly from the set value, the sample should be marked as an abnormal sample, or reassigned to the corresponding range according to the actual delay time.

[0099] During the post-inflation process, except for the post-inflation delay time, other process conditions should be kept as constant as possible, including post-inflation pressure, holding time, rim type, tire mounting direction, cooling medium, and ambient temperature. This ensures that subsequent test results primarily reflect the impact of the post-inflation delay time, rather than interference from other process variables.

[0100] After vulcanization, tires exhibit lower modulus and higher viscoelasticity at high temperatures, and unreleased thermal stress remains within the tire carcass. If the delay time is too short, the internal stress of the tire will not be fully relaxed before entering the post-inflation and shaping state, potentially leading to uneven local recovery of the tire carcass. If the delay time is too long, the tire will bear its own weight and external loads during high-temperature suspension, robotic support, or transfer, potentially causing misalignment of the steel wire bead or deformation of the bead area. Therefore, the different delay time samples obtained in this step are the basis for subsequent judgments on the "adequacy of thermal stress release" and "bead structure stability."

[0101] (III) S3. Inspection of steel wire ring structure and establishment of feasible domain

[0102] Combination Figure 3 and Figure 4 This step differs from the method of selecting the delay time solely based on the uniform motion index. This invention first uses the structural stability of the wire ring as a screening constraint to avoid misjudging a time point with structural risks but occasionally better uniform motion data as the optimal delay time.

[0103] After the post-inflation cooling is completed, the tires corresponding to different post-inflation delay times are subjected to X-ray inspection. During inspection, multiple inspection positions are selected along the tire circumference, such as 8, 12, or 16 circumferential positions. An X-ray image of the bead area is acquired at each inspection position, and the inner edge, outer edge, or center line of the bead are identified. To improve positioning accuracy, grayscale enhancement, edge extraction, noise filtering, and contour fitting processing can be applied to the images.

[0104] For the The offset of the steel wire ring of the tire corresponding to the post-inflation delay time can be determined by the following formula:

[0105] ;

[0106] In the formula, Post-inflation delay time The corresponding wire loop offset; This is a conversion factor for image pixel size; Post-inflation delay time The corresponding tire is at the The first circumferential detection position, the first Image coordinates of feature points on the edge of the steel wire loop; The image coordinates of the same circumferential detection position and the same steel wire ring edge feature point in the reference tire or design reference; This is the coordinate distance operator.

[0107] The above formula uses the maximum offset as the wire carbide offset, which can capture the most unfavorable local structural location. For tires that are sensitive to local wire carbide misalignment, local tension, or local warping, using the maximum offset is more effective than using the average offset in identifying structural risks. If further robustness is required, the maximum offset, average offset, and quantile offset can be combined for judgment.

[0108] The difference in offset between the left and right steel wire rings of the same tire can be expressed as:

[0109] ;

[0110] In the formula, Post-inflation delay time Corresponding to the offset difference of the steel wire rings on both sides of the tire; This is the offset of the left steel wire loop; This represents the offset of the right-side wire loop.

[0111] When the misalignment difference between the two steel wire rings is large, even if the maximum misalignment on one side has not exceeded the allowable threshold, it may indicate that the tire is subjected to uneven stress during transfer or high-temperature storage, posing a risk of bead misalignment. Therefore, this invention preferably incorporates both the steel wire ring misalignment and the misalignment difference between the two steel wire rings for structural determination.

[0112] The structural deformation judgment value can be determined according to the following formula:

[0113] In the formula, This is the value for determining structural deformation. Post-inflation delay time The corresponding wire loop offset; This refers to the allowable offset threshold for the wire coil; This refers to the difference in offset between the steel wire rings on both sides of the same tire; The threshold for the allowable difference in offset between the two steel wire coils. When, it indicates that the corresponding tire has not experienced excessive wire wire offset; when When this occurs, it indicates that the corresponding tire has a structural abnormality risk.

[0114] Furthermore, the structurally feasible region can be represented as:

[0115] ;

[0116] In the formula, For structurally feasible regions; For the first Post-inflation delay time; Post-inflation delay time The corresponding wire loop offset; The allowable wire loop offset threshold; This is the value for determining structural deformation.

[0117] The technical significance of this step lies in transforming the tire post-inflation delay time optimization problem from a simple optimization of uniform dynamic performance to "optimization of uniform dynamic performance under structural constraints." After vulcanization, the tire is in a high-temperature state, and there is a coupling of thermal stress, shrinkage stress, and external forces between the rubber overlay, steel wire bead, and cord end in the bead area. If only uniform dynamic indicators such as RFV or CON are used for judgment, samples with longer delay times might be selected because a longer dwell time can sometimes facilitate local stress release; however, such samples may already have steel wire bead position displacement or bead structure instability risks. By establishing a structurally feasible region, unsafe time points can be eliminated before model calculations, ensuring that the subsequently determined optimal time window does not sacrifice bead structure stability.

[0118] (iv) S4, uniform dynamic performance test and data acquisition

[0119] Combination Figure 5The uniformity performance of tire samples within the structurally feasible region was tested. During the test, the tires were mounted on a uniformity testing device and rotated at a specified inflation pressure, load, and testing speed to obtain parameters such as radial force variation (RFV), first-order radial force harmonic (RFH1), lateral force variation (LFV), and taper (CON).

[0120] Among them, RFV represents the fluctuation amplitude of radial force during tire rotation, reflecting the radial stiffness and geometric consistency of the tire body; RFH1 represents the first harmonic component of the radial force change, reflecting the overall eccentricity, circumferential non-uniformity or forming deviation of the tire; LFV represents the fluctuation amplitude of lateral force during tire rotation, reflecting the uniformity of the tire's lateral structure; CON represents the tire taper, reflecting the lateral deflection trend caused by the asymmetry of the tire's two-sided structure, material distribution and stress state.

[0121] For each post-inflation delay time, it is preferable to test multiple samples and take the sample mean as the index value corresponding to that delay time. The sample mean of the dynamic parameter can be expressed as:

[0122] ;

[0123] In the formula, For uniform dynamic parameters Post-inflation delay time The sample mean; Post-inflation delay time The corresponding number of valid samples; Post-inflation delay time Next Average dynamic parameters of a tire The test value.

[0124] To mitigate the impact of outlier test values, outlier identification can be further performed on samples within the same time gradient. When the mean dynamic parameter of a sample deviates from the group mean by more than a preset multiple of the standard deviation, and is confirmed by retesting to be a detection or production anomaly, that sample can be removed from the data of that time gradient. Samples confirmed as genuine process fluctuations should not be arbitrarily removed, but rather used as a reflection of the stability of that delay time.

[0125] The technical purpose of this step is to obtain a quantitative impact of the post-inflation delay time on the tire's uniform dynamic performance. If the delay time is too short, insufficient release of internal thermal stress in the tire carcass can easily lead to uneven distribution of residual stress during the post-inflation shaping process, resulting in increased RFV, RFH1, or CON. With an appropriately extended delay time, the tire carcass chain segments relax more fully, residual stress tends to be more balanced, and uniform dynamic performance improves. If the delay time is too long, although some stress is released more fully, the high-temperature tire is more affected by its own weight and mechanical load, increasing the risk of bead misalignment and local structural deformation, and uniform dynamic performance may deteriorate again. Therefore, uniform dynamic performance testing, together with structural inspection, can reflect the dual impact of the delay time.

[0126] (V) S5. Normalization and Indicator Unification

[0127] Combination Figure 6 Since RFV, RFH1, LFV, CON, and wire coil offset have different physical meanings, dimensions, and numerical ranges, they cannot be directly added together for comparison. Therefore, this invention normalizes the above indicators to form a unified cost-based evaluation index.

[0128] The normalized index of the mean dynamic parameter can be calculated using the following formula:

[0129] ;

[0130] In the formula, For uniform dynamic parameters Post-inflation delay time The normalized value below; For uniform dynamic parameters Post-inflation delay time The sample mean; For uniform dynamic parameters The maximum sample mean within the structurally feasible region; For uniform dynamic parameters The minimum sample mean within the structurally feasible region; To prevent the correction factor from being zero in the denominator.

[0131] The normalized index of wire coil offset can be calculated using the following formula:

[0132] ;

[0133] In the formula, Post-inflation delay time The corresponding normalized index of the wire coil; Post-inflation delay time The corresponding wire loop offset; This represents the maximum value of the wire loop offset within the structurally feasible domain. This represents the minimum offset of the wire loop within the structurally feasible domain. To prevent the correction factor from being zero in the denominator.

[0134] The normalization method described above converts different indicators into evaluation quantities where smaller values ​​are considered better. For RFV, RFH1, LFV, CON, and bead offset, these are typically cost-based indicators, meaning smaller values ​​indicate better tire dynamic performance or structural stability. If certain benefit-based indicators, such as pass rate or stability index, are introduced in practical applications, they can be converted into cost-based indicators before normalization.

[0135] The technical purpose of this step is to solve the problem of the inability to directly and comprehensively evaluate different physical quantities, enabling structural parameters and uniform dynamic parameters to be included in the same evaluation model. Compared to directly using a single indicator to determine the delay time, normalization can reduce the impact of dimensional differences on the evaluation results, making subsequent weight settings and comprehensive scoring more interpretable.

[0136] (vi) S6. Weight Determination and Comprehensive Evaluation Model Construction

[0137] Combination Figure 7 This step establishes a comprehensive evaluation model based on normalized indicators. The weights can be determined comprehensively based on the sensitivity of different indicators to the post-inflation delay time, quality control priorities, and structural safety requirements. Preferably, this invention determines the weights based on the relative change of each indicator under different post-inflation delay times, so that indicators that are more sensitive to changes and have a more significant impact on quality contribute more to the comprehensive evaluation.

[0138] The relative change amplitude of the mean dynamic parameter can be calculated using the following formula:

[0139] ;

[0140] In the formula, For uniform dynamic parameters The relative magnitude of change; For uniform dynamic parameters The maximum sample mean within the structurally feasible region; For uniform dynamic parameters The minimum sample mean within the structurally feasible region; To prevent the correction factor from being zero in the denominator.

[0141] The weights can be calculated using the following formula:

[0142] ;

[0143] In the formula, For uniform dynamic parameters The weights; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters The relative magnitude of change within the structurally feasible region; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters The relative magnitude of change within the structurally feasible region; The priority coefficient for the offset of the wire coil; This represents the relative variation of the wire loop offset within the structurally feasible region.

[0144] In practical applications, the taper (CON) and bead offset can be given higher priority coefficients. This is because CON typically has a significant impact on vehicle straight-line stability and the risk of veergence, while the bead offset directly reflects the stability of the tire bead structure. For production lines where uniformity pass rate is the primary control objective, the priority coefficients of RFV and RFH1 can be appropriately increased; for large-size tires with higher bead structure risks, the priority coefficient of the bead offset can be further increased.

[0145] The comprehensive evaluation function can be expressed as:

[0146] ;

[0147] In the formula, Post-inflation delay time The corresponding comprehensive evaluation value; It is a set of uniform dynamic parameters consisting of RFV, RFH1, LFV and CON; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters The weights; For uniform dynamic parameters Post-inflation delay time The normalized value below; This is the weight of the wire coil offset. For the offset of the wire coil Post-inflation delay time The normalized value below.

[0148] The comprehensive evaluation function is a cost-based evaluation function; the smaller the value, the better the overall results of structural stability and uniform motion performance under the corresponding post-inflation delay time. By using the steel wire ring offset as one of the evaluation items, and by excluding structurally abnormal time points through the structural feasible region beforehand, this invention forms a "two-layer structural control": the first layer is structural threshold control to prevent structurally abnormal samples from entering the optimal judgment; the second layer is comprehensive evaluation control, so that time points with smaller structural offsets and better uniform motion indicators obtain lower comprehensive evaluation values.

[0149] The technical significance of this step lies in establishing a unified evaluation model that can simultaneously reflect structural stability and uniform dynamic performance. In existing production, the post-inflation delay time is usually determined empirically or adjusted based on only a single quality indicator, which easily leads to problems of overlooking one aspect while focusing on another. This invention, through normalization, weighting, and comprehensive scoring, establishes comparable, calculable, and traceable relationships between various indicators, thereby providing a quantitative basis for determining the post-inflation delay time.

[0150] (vii) S7. Trend fitting and determination of the optimal post-inflation delay time window

[0151] Combination Figure 8 After obtaining the comprehensive evaluation value corresponding to each post-inflation delay time within the feasible domain, a continuous function is fitted to the post-inflation delay time and the comprehensive evaluation value to obtain the delay time-comprehensive evaluation trend curve. The fitting method can be quadratic polynomial fitting, cubic polynomial fitting, piecewise polynomial fitting, exponential fitting, or locally weighted regression fitting. For cases with few sample points, quadratic polynomial or piecewise fitting is preferred to avoid overfitting; for cases with many sample points and complex trends, locally weighted regression or spline fitting can be used.

[0152] The comprehensive evaluation fitting function can be expressed as:

[0153] ;

[0154] In the formula, Continuous post-inflation delay time The corresponding comprehensive evaluation value of the fit; This is a function obtained by fitting the comprehensive evaluation value at each time point within the structurally feasible domain; This is the variable for the continuous post-inflation delay time.

[0155] The fitting function for the wire coil offset can be expressed as:

[0156] ;

[0157] In the formula, Continuous post-inflation delay time The corresponding fitting wire loop offset; This is a function obtained by fitting the wire loop offset under different post-inflation delay times; This is the variable for the continuous post-inflation delay time.

[0158] The optimal post-inflation delay time window can be determined using the following formula:

[0159] ;

[0160] In the formula, To achieve the optimal post-inflation delay time window; The continuous post-inflation delay time is a variable; The offset of the wire loop varies with the continuous post-inflation delay time. A changing fitted function; This refers to the allowable offset threshold for the wire coil; The comprehensive evaluation value varies with the continuous post-inflation delay time variable. A changing fitted function; This represents the minimum value of the comprehensive evaluation value of the fit within the structurally feasible region. This is the window tolerance coefficient that allows deviations from the minimum comprehensive evaluation value.

[0161] in, The tolerance coefficient can be determined based on the production control precision and quality control requirements. For example, when the equipment cycle time control precision is high and the quality requirements are strict, a smaller tolerance coefficient can be used; when there are certain fluctuations in the production cycle time, the tolerance coefficient can be appropriately increased to form a time window that is convenient for actual execution.

[0162] In some cases, the minimum fitted point of the comprehensive evaluation value may be close to the upper boundary of the structural feasible region. If the wire loop offset rapidly approaches the threshold with increasing delay time, the upper limit of the optimal time window should not be set too high. Instead, the time point corresponding to the wire loop offset threshold or its preceding safety margin time should be used as the upper limit of the window. This can prevent production fluctuations from causing the actual delay time to exceed the structural safety boundary.

[0163] The technical function of this step is to transform discrete test points into a continuous process window. Production cannot always be precisely controlled at a single point in time; therefore, simply determining the "optimal time point" is insufficient to guide actual production. This invention determines the continuous time window through curve fitting and tolerance range, ensuring that the post-inflation delay time is both optimal for evaluation and feasible for production, while also being tolerable for cycle time.

[0164] IV. Specific Application Examples

[0165] The following combination Figure 10 Application examples of the present invention will be described. Figure 10The upper part shows X-ray images of the bead area under different post-inflation delay times. The steel wire bead edges of the samples corresponding to 30s, 60s, and 90s are continuous and stable in position, with no obvious local warping or displacement. The sample corresponding to 120s shows abnormal steel wire bead position in the red marked area, which is manifested as a significant displacement of the local edge of the bead relative to the reference position. Figure 10 The lower section presents the tire dynamic performance test results corresponding to different post-inflation delay times, including four indicators: RFV, RFH1, LFV, and CON. Figure 10 It is known that the post-inflation delay time is neither as short nor as long as possible, but rather there is an optimal time window that balances thermal stress release and bead structure stability.

[0166] Application Example 1: Test for Determining the Rear Inflation Delay Time Window of 265 / 60R18 Tires

[0167] This application example uses 265 / 60R18 tires of the same specification as the test objects. The test tires were produced under the same vulcanization process conditions, using the same vulcanization temperature, vulcanization pressure, vulcanization time, post-inflation pressure, and post-inflation cooling time. After vulcanization, four post-inflation delay time gradients of 30s, 60s, 90s, and 120s were set. The post-inflation delay time is the time from when the vulcanizing machine opens the mold to when the tire reaches the initial shaping pressure at the post-inflation station.

[0168] After each tire set is inflated and cooled, an X-ray structural inspection is performed first, followed by a uniform dynamic performance test. The X-ray inspection focuses on observing whether there is any displacement, warping, or localized continuity abnormalities in the position of the steel wire rings in the bead area. The uniform dynamic performance test obtains the radial force variation (RFV), first-order radial force harmonic (RFH1), lateral force variation (LFV), and taper (CON). All test conditions are kept consistent to eliminate the influence of differences in inflation pressure, testing equipment, test load, and tire alignment methods on the results.

[0169] 1. Evaluation results of the wire ring structure

[0170] Combination Figure 10 The upper X-ray images show that the wire bead area in the 30s, 60s, and 90s samples is continuous and no obvious deformation was observed. In the 120s sample, the edge of the wire bead appears abnormal in the area selected in red, indicating that when the vulcanized tire is left in a high-temperature state for too long, the bead area is at risk of structural deformation under its own weight, mechanical gripping, or transferred load.

[0171] To transform image observations into quantifiable metrics, this application example uses a pixel-based method to calculate the wire loop offset. The calculation method is as follows:

[0172] ;

[0173] In the formula, Post-inflation delay time The corresponding wire loop offset; This refers to the pixel size conversion factor for X-ray images. Post-inflation delay time Next The first circumferential detection position, the first Image coordinates of feature points on the edge of the steel wire loop; The coordinates of the feature point on the edge of the wire ring at the same location in the reference sample or design datum; This is the coordinate distance operator.

[0174] according to Figure 10 Based on the structural state of the X-ray image shown, and combined with pixel-based quantization, the following structural evaluation results can be obtained.

[0175]

[0176] In this application example, the allowable offset threshold for the wire ring is set to 0.50 mm. Therefore, the feasible region of the structure can be represented as follows:

[0177] ;

[0178] In the formula, The feasible region is defined as 30s, 60s, and 90s, which are the post-inflation delay times when the wire ring offset does not exceed the allowable threshold and no obvious structural abnormalities occur.

[0179] The results above show that although a 120s delay time still allows for post-inflation, significant structural risks have emerged in the bead area, making it unsuitable as a candidate for the optimal post-inflation delay time. This demonstrates the necessity of prioritizing bead structure constraint screening in this invention, avoiding the problem of neglecting bead structure safety by simply selecting a time point based on uniform motion parameters.

[0180] 2. Results of uniform dynamic performance test

[0181] Figure 10 The lower bar chart presents the tire dynamic performance test results under different rear inflation delay times. The values ​​in the chart are summarized below.

[0182]

[0183] The data in the table shows that RFV is 8.2, RFH1 is 5.0, LFV is 5.1, and CON is 2.8 with a 30s delay time. All four indicators are relatively high, indicating that when the tire enters the post-inflation station immediately or quickly after vulcanization, the internal thermal stress of the tire body has not been fully released. During the post-inflation shaping process, uneven distribution of residual stress is likely to form, which leads to deterioration of uniform dynamic performance.

[0184] When the post-inflation delay time was 60 s, RFV decreased to 7.3, RFH1 decreased to 4.6, LFV decreased to 4.0, and CON decreased to 0.6. Specifically, CON decreased by approximately 78.6% compared to 30 s, LFV by approximately 21.6%, RFV by approximately 11.0%, and RFH1 by approximately 8.0%. This result indicates that appropriately extending the delay time between vulcanization and post-inflation is beneficial for releasing internal thermal stress in the tire carcass and improving the uniformity of radial and lateral stress distribution.

[0185] When the post-inflation delay time was extended to 90s, RFH1 further decreased to 4.4, but RFV increased to 7.7, LFV increased to 4.5, and CON increased to 2.2, and the bead offset increased compared to 60s. These results indicate that while further extending the delay time may improve some harmonic parameters, it does not consistently benefit the overall uniform dynamic performance, especially negatively impacting the stability of CON and the bead structure.

[0186] When the post-inflation delay reaches 120s, RFV is 7.3, RFH1 is 4.1, LFV is 4.5, and CON is 2.5. Looking at some of the average dynamic parameters, 120s is not the worst for all, but considering... Figure 10 The X-ray examination of the upper part revealed a local structural anomaly in the wire coil at this time point. Therefore, 120 seconds cannot be considered the optimal delay time. This further illustrates that the method of "prioritizing structural constraints and comprehensively evaluating uniform motion performance" adopted in this invention can avoid making erroneous judgments based solely on a single uniform motion index.

[0187] 3. Comprehensive evaluation model and calculation results

[0188] To further demonstrate that this invention can quantitatively screen the optimal post-inflation delay time, this application example incorporates RFV, RFH1, LFV, CON, and wire coil offset into a comprehensive evaluation. Since the dimensions and numerical ranges of each indicator differ, normalization is performed before calculating the comprehensive evaluation value.

[0189] The normalization formula for the uniform dynamic parameter is as follows:

[0190] ;

[0191] In the formula, For uniform dynamic parameters Post-inflation delay time The normalized value below; For uniform dynamic parameters Post-inflation delay time The sample mean; For uniform dynamic parameters The maximum sample mean within the structurally feasible region; For uniform dynamic parameters The minimum sample mean within the structurally feasible region; To prevent the correction factor from being zero in the denominator.

[0192] The normalized formula for the wire coil offset is as follows:

[0193] ;

[0194] In the formula, Post-inflation delay time The corresponding normalized index of the wire coil; Post-inflation delay time The corresponding wire loop offset; This represents the maximum value of the wire loop offset within the structurally feasible domain. This represents the minimum offset of the wire loop within the structurally feasible domain. To prevent the correction factor from being zero in the denominator.

[0195] The comprehensive evaluation function is as follows:

[0196] ;

[0197] In the formula, Post-inflation delay time The corresponding comprehensive evaluation value; This is the normalized value of RFV; This is the normalized value of RFH1; This is the normalized value of LFV; This is the normalized value of CON; This is the normalized value of the wire coil offset; , , , , These are the weights of the corresponding indicators.

[0198] In this application example, considering the relative change rates of each indicator and the priority of quality control, the following is taken:

[0199] ;

[0200] In the formula, For RFV weights; For RFH1 weights; LFV weights; For CON weights; The weights for the wire bead offset are as follows: Since CON has a significant impact on vehicle siding tendency and tire straight-line stability, and the wire bead offset has a direct impact on the safety of the tire bead structure, CON and wire bead offset are given high weights in this application example.

[0201] After eliminating the 120s time point where the structure was unqualified, a comprehensive evaluation was conducted on the three feasible time points of 30s, 60s, and 90s, and the following results were obtained.

[0202] 30s qualified 1.160 3 60s qualified 0.121 1 90s qualified 1.118 2 120s Unqualified Not participating in the optimal evaluation —

[0203] The comprehensive evaluation results show that the lowest comprehensive evaluation value is found at 60s, significantly lower than 30s and 90s, and no abnormalities were observed in the steel wire ring structure. Therefore, the area around 60s can be determined as the center value of the optimal rear inflation delay time window for the 265 / 60R18 tire in this application example.

[0204] 4. Comparison with the comparative example

[0205] To further illustrate the technical effects of the present invention, a delay time of 60s can be used as an example, and 30s, 90s and 120s can be used as comparative examples.

[0206]

[0207] Compared to the 30s comparison example, Example 1 showed a decrease in RFV from 8.2 to 7.3, LFV from 5.1 to 4.0, and CON from 2.8 to 0.6, indicating that appropriately extending the delay time can improve tire dynamic performance. Compared to the 90s comparison example, although Example 1 had a slightly higher RFH1, its RFV, LFV, and CON were all better, and the wire bead offset was smaller, indicating that the 60s method achieved a better balance between structural stability and overall dynamic performance. Compared to the 120s comparison example, Example 1 did not show any... Figure 10 The abnormality of the wire bead shown in the red box indicates that it can avoid the risk to the tire bead structure caused by excessive delay time.

[0208] Therefore, the technical effect of this invention does not simply stem from "increasing the delay time," but rather from the windowed determination of the post-inflation delay time after structural constraints and comprehensive evaluation. This method can identify a reasonable range between "insufficient thermal stress release due to being too short" and "increased risk of wire ring deformation due to being too long."

[0209] The above application examples demonstrate that the present invention can transform the post-inflation delay time after vulcanization from an empirically set value into a quantifiable and determinable process parameter. Figure 10The test results show that the tire's uniform motion performance is poor at a 30s delay time, indicating that too short a delay is not conducive to the release of thermal stress in the tire body; local structural abnormalities appear in the bead at a 120s delay time, indicating that too long a delay will bring the risk of bead structural deformation; at a 60s delay time, no structural abnormalities appear in the bead, and key uniform motion indicators such as RFV, LFV, and CON are significantly improved, resulting in the lowest comprehensive evaluation value. Therefore, this invention, through the method of "screening the feasible domain of bead structure + comprehensive evaluation of uniform motion performance," can determine the optimal post-inflation delay time window that balances structural stability and uniform motion performance, thereby improving the consistency of finished tires, reducing the risk of poor uniform motion and bead structural abnormalities, and providing a reliable basis for the cycle control of the tire unloading robot and post-inflation station in the vulcanizing machine.

[0210] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

[0211] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0212] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0213] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0214] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0215] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0216] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0217] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

Claims

1. A method of determining the post-vulcanization inflation delay time of a tire, characterized in that, The method includes the following steps: S1. Select multiple vulcanized tires of the same specification, under the same vulcanization conditions, the same transfer method, and the same post-inflation station conditions as test samples, and set multiple different post-inflation delay times. The post-inflation delay time The time between the completion of mold opening in the tire vulcanizing machine and the tire reaching the initial shaping pressure at the rear inflation station; S2, according to each The vulcanized tires were transferred, stored, and then inflated. After the inflated tires cooled down, the steel wire bead structure was inspected, and the inflated tire delay time was recorded. Corresponding wire coil offset ; S3, according to Offset threshold of the preset steel wire coil Establish the structurally feasible region ; S4, for those in each within The corresponding tires were subjected to uniform dynamic performance testing to obtain at least the radial force variation. First-order radial force harmonics lateral force changes and taper The uniform dynamic parameters; S5, regarding the uniformity parameters and Normalization was performed to obtain each Corresponding moving average normalized index and the normalized index of wire coil ; S6, based on , And corresponding weights, to establish a comprehensive evaluation function. ; S7, to each after and By performing continuous function fitting, the delay time-comprehensive evaluation trend curve is obtained. Under the condition that the steel wire ring structure does not deform, the time interval with the minimum comprehensive evaluation value or within the optimal tolerance range is selected to determine the optimal after-inflation delay time window after tire vulcanization. .

2. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S1, the plurality of post-inflation delay times Distributed within the range of 15s to 180s, with the interval between two adjacent post-inflation delay times ranging from 10s to 45s, and each post-inflation delay time The number of test tires should be no less than 3.

3. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S2, the steel wire ring structure is inspected using X-ray inspection. At least eight inspection positions are selected along the tire circumference. At each inspection position, the edge feature points of the steel wire ring are identified, and the offset of the steel wire ring is obtained by pixel conversion. The offset of the wire coil Calculate using the following formula: ； In the formula, Post-inflation delay time The corresponding wire loop offset; This is a conversion factor for pixel size; Post-inflation delay time The corresponding tire is at the The first circumferential detection position, the first Image coordinates of feature points on the edge of the steel wire loop; The image coordinates of the same detection location and the same steel wire bead edge feature points in the reference tire or design reference; This is the coordinate distance operator.

4. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S3, the structurally feasible region : ； In the formula, For structurally feasible regions; For the first Post-inflation delay time; Post-inflation delay time The corresponding wire loop offset; The allowable wire loop offset threshold; This is the structural deformation judgment value. When the tire does not exhibit localized warping, misalignment, or discontinuity interruption of the steel wire bead, ; Preferably, the structural deformation determination value Determine using the following formula: In the formula, This is the value for determining structural deformation. Post-inflation delay time The corresponding wire loop offset; This refers to the allowable offset threshold for the wire coil; This represents the difference in offset between the steel wire rings on both sides of the same tire. The allowable threshold for the difference in offset between the two steel wire loops; when At that time, the corresponding post-inflation delay time will be adjusted. From the structural feasible domain Remove from the list.

5. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S5, the dynamic normalization index Calculate using the following formula: ； In the formula, For uniform dynamic parameters Post-inflation delay time Normalized value under; For uniform dynamic parameters Post-inflation delay time The sample mean; For uniform dynamic parameters In the structurally feasible region The maximum sample mean within the range; For uniform dynamic parameters In the structurally feasible region The minimum sample mean within; To prevent the correction factor from being zero; And / or, in step S5, the normalized index of the wire coil Calculate using the following formula: ； In the formula, Post-inflation delay time The corresponding normalized index of the wire coil; Post-inflation delay time The corresponding wire loop offset; For structurally feasible regions The maximum value of the inner wire ring offset; For structurally feasible regions Minimum offset of the inner wire ring; To prevent the correction factor from being zero in the denominator.

6. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S6, the comprehensive evaluation function is: ； In the formula, Post-inflation delay time The corresponding comprehensive evaluation value; For the reason , , and The set of uniform motion parameters constituted; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters The weights; For uniform dynamic parameters Post-inflation delay time Normalized value under; This is the weight of the wire coil offset. For the offset of the wire coil Post-inflation delay time Normalized value under; Preferably, the averaging parameter weight The values ​​are determined based on the relative changes of each uniform dynamic parameter under different post-inflation delay times, and calculated according to the following formula: ； In the formula, For uniform dynamic parameters The weights; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters In the structurally feasible region The relative range of change within; Set of uniform motion parameters Any uniform dynamic parameter in; For uniform dynamic parameters Priority coefficient; For uniform dynamic parameters In the structurally feasible region The relative range of change within; The priority coefficient for the offset of the wire coil; For the offset of the wire loop within the structurally feasible region The relative range of change within; Furthermore, the relative change range Calculate using the following formula: ； In the formula, For uniform dynamic parameters The relative range of change; For uniform dynamic parameters In the structurally feasible region The maximum sample mean within the range; For uniform dynamic parameters In the structurally feasible region The minimum sample mean within; To prevent the correction factor from being zero in the denominator.

7. The method for determining the post-inflation delay time after tire vulcanization according to claim 1, characterized in that, In step S7, the optimal post-inflation delay time window Determine using the following formula: ； In the formula, To achieve the optimal post-inflation delay time window; The continuous post-inflation delay time is a variable; The offset of the wire loop varies with the continuous post-inflation delay time. A changing fitted function; This refers to the allowable offset threshold for the wire coil; The comprehensive evaluation value varies with the continuous post-inflation delay time variable. A changing fitted function; For structurally feasible regions The minimum value of the overall evaluation value of the inner fit; This is the window tolerance coefficient that allows deviations from the minimum comprehensive evaluation value; And / or, in step S7, the continuous function fitting includes at least one of quadratic polynomial fitting, cubic polynomial fitting, piecewise polynomial fitting, exponential fitting, or locally weighted regression fitting; when the minimum point of the fitted comprehensive evaluation value is close to the structurally feasible region. When the upper boundary is reached, the wire loop offset threshold is used. The corresponding post-inflation delay time is used as the optimal post-inflation delay time window. The upper limit; Preferably, after determining the optimal post-inflation delay time window Then, the optimal post-inflation delay time window is... This serves as the process control parameter for the tire unloading robot, tire transfer device, or post-inflation station controller in the vulcanizing machine; and it periodically collects data from tires of the same specification during mass production. , , , and wire coil offset When any parameter is relative to the determined optimal post-inflation delay time window If the baseline value exceeds the threshold and drifts, steps S1 to S7 are re-executed to update the optimal post-inflation delay time window. .

8. A system for implementing the method of any one of claims 1-7, the system comprising a production control system, a post-inflation execution system, a structural inspection system, a dynamic performance inspection system, and an evaluation modeling system; The production control system is used to record the opening time of the vulcanizing machine, the movement time of the tire unloading robot, the moment the tire leaves the mold, the moment the tire enters the post-inflation station, and the moment the initial shaping pressure is reached. It also controls the post-inflation delay time of different sample tires according to the test plan. The rear inflation system includes a tire removal robot, a tire transfer device, a rear inflation rim, inflation lines, a pressure control valve, and a cooling control unit. This system is used to complete tire transfer within a set rear inflation delay time and to inflate, shape, and cool the tire at the rear inflation station. The structural inspection system is preferably an X-ray inspection system, which includes an X-ray imaging device, a tire positioning mechanism, an image acquisition module, and an image processing module. This system is used to acquire images of the wire loop at different circumferential positions, identify feature points on the edge of the wire loop, and obtain the offset of the wire loop through pixel conversion. The uniform dynamic performance testing system is used to test the uniform dynamic parameters such as RFV, RFH1, LFV, and CON of sample tires with different delay times; The evaluation modeling system receives the offset of the wire ring and the uniform dynamic parameters, normalizes the indicators of different dimensions, calculates the weight coefficients and comprehensive evaluation values, and obtains the delay time-comprehensive evaluation trend curve through continuous function fitting, and finally outputs the optimal post-inflation delay time window.

9. An electronic device, characterized in that, The method includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 1 to 7.

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