Method and system for regulating inherent frequency and excitation source to improve tire cavity noise

Abstract

The invention relates to the technical field of tire production, in particular to a method and system for regulating and controlling inherent frequency and an excitation source to improve tire cavity noise. According to the method, the weight and the perimeter of a tire blank are collected, the cavity noise peak frequency is predicted, and extrusion fitting and forming parameters are adjusted in a feedforward write-back mode so as to lock the inherent frequency; the vulcanization secondary shaping pressure is controlled to be 0.05-0.07 MPa, peak overshoot is limited not to exceed 0.02 MPa, and RFV8H excitation caused by uneven internal stress is inhibited; and meanwhile, no less than 12 clamping block transfer rings are adopted to weaken circumferential periodic disturbance. After vulcanization, target parameters are updated in a closed-loop mode through double indexes of RFV8H and peak frequency, and the noise risk and the customer complaint rate of the 200-250 Hz sensitive frequency band are remarkably reduced.

Description

Technical Field

[0001] This invention relates to the field of tire manufacturing technology, and in particular to a method and system for adjusting the natural frequency and excitation source to improve tire cavity noise. Background Technology

[0002] Tire cavity noise (also known as tire cavity resonance noise) is a typical and difficult-to-suppress narrowband noise in vehicle NVH performance. When a vehicle is in motion, the air within the annular closed cavity formed by the tire and rim undergoes acoustic resonance under periodic external excitation, producing a perceptible humming / roaring characteristic peak inside the vehicle. In engineering practice, this noise peak frequency often falls within the 200–250 Hz range, which is sensitive to human hearing, and is highly sensitive to batch, equipment, and operating conditions. Because the tire manufacturing process involves multiple continuous steps such as molding, shaping, and vulcanization, even slight fluctuations in any step can alter the inherent characteristics of the cavity system or enhance the excitation source, leading to a drift in the peak frequency of the cavity noise or an increase in the peak sound pressure level, thus causing customer complaints and rework.

[0003] From a mechanistic perspective, the formation of cavity noise typically involves three coupled elements: first, the excitation source, namely the periodic excitation of the tread / carcass caused by radial force fluctuations and their harmonic components due to tire rolling unevenness; second, the transmission path, namely the influence of carcass structural stiffness, prestress distribution, and circumferential uniformity on the transmission efficiency of excitation energy and the degree of modal coupling; and third, the acoustic cavity system itself, namely the natural frequency and resonant modes determined by the tire's internal cavity geometry and boundary conditions. These elements are not isolated under mass production conditions: for example, the weight and distribution of the tire blank, the tire blank circumference and its dispersion, the setting and transient peaks of the vulcanization and shaping pressure curve, and the circumferential periodic disturbances caused by the molding clamping and transfer processes all simultaneously affect the natural frequency-transmission path-excitation source link, causing the cavity noise to exhibit significant batch-level fluctuations. Therefore, improvements in a single aspect often only reduce noise in stages or are effective on specific specification platforms, making it difficult to maintain consistency across batches and equipment conditions.

[0004] In existing technologies, improvements to cavity noise can be broadly categorized into the following approaches.

[0005] The first approach focuses on weakening the excitation source by improving the uniformity harmonic index. For example, patent document CN111805955A discloses a tire manufacturing process for reducing cavity noise. It reduces the eighth harmonic component (such as RFV8H) related to cavity noise and achieves noise improvement by controlling the misalignment angle of eight movable mold modules. The advantage of this approach is that it establishes a relatively direct engineering correlation between cavity noise and uniformity harmonic index and provides a control approach based on mold structure / phase relationship. However, the technical focus of this approach is mainly on the misalignment angle of the mold modules and its impact on RFV8H, which is a targeted optimization for a specific process / mold structure. It does not systematically reveal or solve the combined problem of inherent frequency drift and excitation enhancement caused by tire blank weight fluctuation, tire blank circumference drift, vulcanization shaping pressure curve peaks, etc., and in the scenario of multi-specification and multi-mold parallel production, the portability and batch stability of simply relying on the mold misalignment angle may still be limited.

[0006] The second approach focuses on detecting and improving the circumferential dimensions / roundness of the tire blank at the forming stage or during manufacturing, thereby enhancing geometric uniformity and dynamic uniformity. For example, patent document CN211000071U discloses a tire blank roundness identification and improvement device. By adding a laser sensor to the forming machine, the circumferential state of the tire blank is detected, and the tire crown transfer ring and drive mechanism are used to improve the out-of-roundness or circumferential dimension distribution of the tire blank. The advantage of this approach is that it moves control forward to the manufacturing process, reducing the lag in finished product detection—rework and scrap, and improving the circumferential consistency of the tire blank to a certain extent. However, such solutions typically focus on roundness, dimensional uniformity, or dynamic performance, without locking the peak frequency of cavity noise as the core control object. They also fail to establish a prediction and write-back mechanism between changes in tire blank weight / circumference and the inherent frequency drift of the tire-air system. Furthermore, the curve shape of the secondary curing pressure (especially the pressure peak overshoot spike) amplifies the effects of uneven internal stress and harmonics such as RFV8H in such solutions. This results in cavity noise fluctuations even if the geometry at the molding end is improved, due to periodic disturbances introduced during the curing or clamping and transfer processes.

[0007] The third approach focuses on acoustic sound absorption / damping design or model optimization to reduce cavity resonance response. For example, patent document CN114218827B discloses a parameter design method for suppressing tire cavity resonance noise. By establishing an acoustic model, it optimizes the parameters (such as thickness, width, and flow resistance) of the sound-absorbing material attached to the inner surface of the tire, thereby suppressing cavity resonance noise. This approach has a certain systematicity in theoretical modeling and parameter optimization, and can directly affect the response amplitude of the acoustic cavity system; however, it is usually accompanied by engineering problems such as increased weight, increased cost, and higher requirements for durability, reliability, and process consistency due to material attachment. Furthermore, this approach is more inclined to attenuate the acoustic cavity response, and cannot solve the problems caused by the enhancement of excitation sources during the manufacturing process (such as an increase in RFV8H) and the drift of inherent frequencies (such as peak frequencies falling into sensitive frequency bands due to fluctuations in tire circumference / weight). Therefore, under mass production conditions, there may still be situations where the device is effective but customer complaints about fluctuations still occur.

[0008] In summary, existing technologies reveal two main issues: First, solutions for cavity noise often focus on a single aspect, lacking a comprehensive control mechanism that integrates natural frequency stabilization, transmission path stabilization, and excitation source reduction into a unified framework. Second, key variables affecting cavity noise during tire manufacturing exhibit significant coupling. For instance, the tire blank circumference is not only determined by molding but also influenced by the secondary vulcanization pressure and its transient peaks. The tire blank weight and its distribution not only affect quality control but also alter the equivalent mass and natural frequency of the tire-air system. The number of clamping points and the uniformity of force during clamping and transfer may introduce circumferential periodic disturbances, thereby enhancing specific harmonic excitations. Existing technologies typically lack a systematic correlation model and closed-loop write-back strategy for the weight-circumference-vulcanization pressure curve (including peak overshoot), clamping periodic disturbances, RFV8H, and cavity noise peak frequency / amplitude. This makes it difficult to maintain stable cavity noise reduction effects over the long term, especially in multi-equipment, multi-batch production environments.

[0009] Therefore, there is an urgent need in this field for a systematic approach that is feasible for mass production: not only can key state quantities such as tire weight and circumference be used for natural frequency stabilization and risk prediction during the manufacturing process, but also the curve shape (especially peak overshoot) of the secondary molding pressure of vulcanization can be constrained, and the molding clamping and transfer structure can be optimized to suppress harmonic excitation sources such as RFV8H, so as to achieve systematic suppression of cavity noise and improve batch consistency, thereby reducing the noise risk and the probability of customer complaints in the sensitive frequency band of 200-250Hz. Summary of the Invention

[0010] The technical objective of this invention is to provide a system method for mass production, addressing the problem that tire cavity noise is prone to occur in the sensitive frequency band of 200-250Hz and has large batch fluctuations. This method uses the weight and circumference of the tire blank to lock the natural frequency of the tire-air system, and coordinates the constraint of the secondary molding pressure and its peak overshoot, and optimizes the molding clamping and transfer structure to reduce the excitation of harmonic radial forces such as RFV8H, thereby achieving source reduction and stable suppression of cavity noise.

[0011] Firstly, in order to achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0012] A method for adjusting the natural frequency and excitation source to improve tire cavity noise, the method comprising the following steps:

[0013] S1, Target peak frequency of tire cavity noise and allowable deviation And determine the target embryo weight corresponding to the target peak frequency. Target perimeter Secondary shaping pressure setting value and the eighth harmonic limit of radial force variation ;

[0014] S2, The measured weight of the tire blank is collected after the tire is formed. and measured perimeter and based on and The peak frequency of cavity noise in the tire-air system is predicted, and the predicted peak frequency is obtained. ;

[0015] when Compared to The deviation exceeds Furthermore, when related to weight deviation, the weight deviation rate of the embryo can be adjusted by regulating the extrusion and bonding process parameters. Keep within the preset range;

[0016] when Compared to The deviation exceeds Furthermore, when related to circumference deviation, the circumferential tension during molding and the secondary shaping pressure are adjusted in a coordinated manner. This causes the embryo's circumference to deviate. Keep within the preset range;

[0017] S3, during the vulcanization process, the pressure curve of the secondary setting stage is monitored and controlled to ensure the pressure peak... With secondary shaping pressure setting value The difference between them does not exceed a preset threshold. At the same time, in the molding clamping and transfer process, a clamping block type transfer ring with no less than 12 clamping blocks is used to weaken the circumferential periodic disturbance. And after vulcanization, the radial force variation of the tire is detected by the eighth harmonic. ,when Exceeding the stated limit Or the actual peak frequency of cavity noise Deviation Exceed Update , or At least one of the above and return to execute S2 to systematically reduce tire cavity noise.

[0018] Preferably, in step S1, the target peak frequency The preset peak frequency of cavity noise allows for a deviation of [missing information]. The allowed frequency width for fluctuation of the peak frequency; and includes the following steps:

[0019] Determine the target weight for the embryo, including the target weight. Upper limit of weight deviation rate The actual weight of the embryo was The weight deviation rate is ;

[0020] Determine the target circumference of the embryo, including the target circumference. Upper limit of deviation from perimeter The measured circumference of the embryo was 100 mm. The perimeter deviation is ;

[0021] Determine the vulcanization setting pressure control target, including the secondary setting pressure setpoint. Lower limit of pressure range and upper limit The secondary shaping pressure setting value The pressure inside the air bladder applied to the inner surface of the tire blank during the secondary shaping stage of vulcanization, and meeting the following requirements. ;

[0022] Determine the upper limit of pressure peak overshoot The maximum value of the internal pressure curve during the secondary shaping stage is The peak pressure overshoot is ;

[0023] And determine the eighth harmonic limit of radial force variation. ,in This is the amplitude of the eighth harmonic of the radial force variation during the tire uniformity test.

[0024] Preferably, in step S2, each embryo is weighed to obtain the weight. And perform a perimeter measurement to obtain and according to , With the target peak frequency Establish or invoke the inherent frequency control relationship to obtain the predicted peak frequency corresponding to the embryo. Among them, the predicted peak frequency The peak frequency of cavity noise is calculated from the tire blank state in the tire-air coupling system.

[0025] When the weight deviation rate is greater than Or predict peak frequency Deviation Exceed Furthermore, when its deviation is related to weight deviation, it is based on the difference. The amount of adhesive supplied per unit length, component thickness, or bonding position in the extrusion and bonding processes are adjusted to ensure that the weight deviation rate of the subsequent preform is no greater than [value missing]. ;

[0026] When the perimeter deviation is greater than Or predict peak frequency Deviation Exceed Furthermore, when its deviation is related to the perimeter deviation, it is based on the difference. The circumferential tension or forming drum size in the molding process is corrected, and the secondary setting pressure setting value is corrected simultaneously. This ensures that the circumference deviation of the subsequent embryo is no greater than [a certain value]. And maintain .

[0027] Preferably, in step S2, the upper limit of the weight deviation rate is... Pick to Furthermore, the weight deviation of key areas of the tire blank or finished tire, including the crown and sidewall, is controlled within the target weight of the corresponding area. within;

[0028] And / or, the upper limit of the perimeter deviation for ;

[0029] And / or, the lower limit of the pressure range for Upper limit of pressure range for And the upper limit of the pressure peak overshoot for Or smaller.

[0030] Preferably, the number of clamping blocks in the clamping block type transfer ring is [not specified]. for Furthermore, the clamping block is a full-size clamping block, which ensures that the tire blank forms at least 12 uniform force points along the circumference during clamping and transfer.

[0031] Preferably, the uniformity test includes tests in both clockwise and counterclockwise directions, yielding results respectively. and And the average of the two is taken as the value of the two. .

[0032] Preferably, the inherent frequency control relationship is a mapping model or lookup table model established based on historical samples, wherein the historical samples at least include the measured weight of the embryo. Measured circumference of the embryo Secondary shaping pressure setting value With the corresponding actual peak frequency Used to output predicted peak frequency .

[0033] Secondly, the present invention also provides a system for improving tire cavity noise by adjusting the natural frequency and excitation source, the system being used to implement the method, comprising:

[0034] The weighing module is used to obtain the measured weight of the embryo. ;

[0035] The circumference measurement module is used to obtain the actual circumference of the embryo. ;

[0036] The vulcanization and setting pressure control module, including a pressure sensor and an actuator, is used to set the secondary setting pressure value. And obtain the pressure peak value of the internal pressure curve during the secondary shaping stage. ;

[0037] The clamping block type transfer ring has the following number of clamping blocks: and ;

[0038] The uniformity test module is used to measure the eighth harmonic of the radial force variation of the tire. ;

[0039] The noise spectrum acquisition module is used to acquire the cavity noise spectrum and determine the actual peak frequency. ;

[0040] Controller, stores target peak frequency Allowable deviation Target weight Upper limit of weight deviation rate Target perimeter Circumference deviation upper limit Lower limit of pressure range and upper limit Pressure peak overshoot limit and the eighth harmonic limit of radial force variation And is configured to perform steps S1 to S5 of the method described.

[0041] Thirdly, the present invention also provides a computer-readable storage medium having a computer program or instructions stored thereon, which, when executed by a processor, implement the steps of the method.

[0042] Fourthly, the present invention also provides a computer program product, including a computer program or instructions that, when executed by a processor, implement the steps of the method.

[0043] This invention incorporates the inherent characteristics of the acoustic cavity system, the transmission path, and the excitation source into a single coordinated control chain, enabling a significant reduction in cavity noise and improved batch stability under mass production conditions. On one hand, by converging control over the weight and distribution of the tire blank and its circumference, the equivalent mass of the tire-air system and the cavity volume are kept stable, thereby locking the cavity resonance peak frequency stably within the target frequency band and significantly reducing peak frequency dispersion. On the other hand, by controlling the secondary vulcanization setting pressure within a reasonable window and limiting pressure peak overshoot, irreversible damage caused by overstretching is suppressed. Uneven internal stress, combined with a transfer ring consisting of no fewer than 12 clamping blocks to weaken circumferential periodic disturbances, reduces the excitation of harmonic radial forces such as RFV8H from the source, thereby weakening the ignition effect on cavity resonance. The overall effect is a significant improvement in uniformity, a reduction in structural risks such as glue edge / interference, a decrease in peak sound pressure level of cavity noise and a reduction in fluctuation. In typical specification verification, it can achieve a reduction of more than 50% in RFV8H, a reduction of approximately several dB in peak sound pressure level, and a significant decrease in related customer complaints, thereby achieving a quieter, more stable, and more easily mass-producible systematic noise reduction effect. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the frequency spectrum of tire cavity noise reported by customers. The diagram shows that the cavity noise has a significant peak in the 200-250Hz frequency band.

[0045] Figure 2 The chart and table show the improvement in tire uniformity after the secondary shaping pressure is reduced from 0.08MPa to 0.06MPa. The uniformity index includes RFV, RFV8H clockwise direction, RFV8H counterclockwise direction, and LFV.

[0046] Figure 3A comparison chart showing the impact of different transfer ring clamping block structures on uniformity indicators, including structural diagrams / photographs of 12-block and 8-block clamping block configurations, as well as comparison curves and data tables of each harmonic component of RFV and RFV8H. Detailed Implementation

[0047] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0048] For ease of explanation, the cavity noise described herein preferably refers to the narrowband resonant noise generated by the vibration of the tire structure in the closed annular cavity formed by the tire and rim during vehicle operation; its peak frequency typically falls within the sensitive range of 200–250 Hz. Figure 1 This illustrates the distribution characteristics of typical customer complaint frequency bands. The present invention also incorporates Table 1... Figure 2 and Figure 3 The influence relationships of key process variables are explained, with Table 1 showing the effect of vulcanization setting pressure on the tire circumference and the tire-mold clearance. Figure 2 The effect of secondary setting pressure on improving uniformity indicators such as RFV8H is presented. Figure 3 The effects of different forming transfer ring structures (8-block and 12-block clamping blocks) on the RFV8H are compared.

[0049] I. Terminology Explanation

[0050] Cavity noise peak frequency The frequency corresponding to the maximum sound pressure level obtained by analyzing the noise spectrum of the tire cavity, in Hz.

[0051] Target peak frequency : The target peak frequency of cavity noise, set in Hz, to avoid sensitive frequency bands and meet the NVH targets of the whole vehicle.

[0052] Allowable deviation : relatively Permissible deviation range, in Hz.

[0053] Embryo weight / Target weight Actual weight of embryo Compared with the preset target weight The unit is g or kg.

[0054] Weight deviation rate : Characterizes the degree of deviation of the embryo weight from the target weight, and is defined as shown in equation (1).

[0055] Embryo circumference / Target perimeter Measured value of embryo circumferential length Perimeter of the design target , unit mm.

[0056] Upper limit of perimeter deviation : relatively Maximum permissible absolute deviation, in mm.

[0057] Secondary shaping pressure With peak pressure Airbag pressure setting value during the secondary curing and setting stage of vulcanization With the maximum value of the pressure curve during this stage , unit MPa.

[0058] Pressure peak overshoot limit : relatively The maximum allowable overshoot is defined in equation (2), in MPa.

[0059] Radial force variation eighth harmonic : The amplitude of the eighth harmonic of the radial force variation signal in the tire uniformity test (which can be measured by CW and CCW respectively), in kgf.

[0060] II. System Structure of the Invention

[0061] The method of this invention is preferably implemented by a manufacturing process collaborative control system, which includes at least the following functional modules (which can be integrated into the tire MES / process control platform, vulcanizing machine control system, and molding machine modification unit). The modules communicate with each other via industrial Ethernet, fieldbus, or OPC-UA to achieve data acquisition, judgment, and write-back control:

[0062] Weighing module: Located at the off-line station after molding or before transfer, it performs 100% weighing on each tire blank and outputs the tire blank weight. It can further output the weight of the zones (such as the crown zone, sidewall zone, etc.) to control the uniformity of weight distribution.

[0063] Perimeter Measurement Module: Preferably, a laser perimeter measuring instrument, a flexible measuring tape standard measuring fixture, or a ring measuring device is used to measure the perimeter of the tire blank. Sampling or full inspections are conducted; in mass production scenarios, stricter inspections are preferred for the first tire blank produced by each molding machine each day, the first tire blank produced when changing specifications / shifts, and the tire blanks when abnormal alarms occur.

[0064] Inherent frequency prediction and evaluation module: used to predict and evaluate the frequency of embryonic key states (including at least...) and It can be expanded to include the gap between the tire blank and the mold, the prestressing proxy index of the tire body, etc., to predict the peak frequency of cavity noise and output the predicted peak frequency. and with the target Perform deviation determination.

[0065] Molding process write-back module: used for... and To address deviations, adjustments are made to process settings such as extrusion glue supply, bonding, molding drum size, and circumferential tension to suppress weight and circumference drift at the source.

[0066] Vulcanization and setting pressure closed-loop control module: Real-time acquisition and control of the pressure curve during the secondary vulcanization and setting stage, including setting... ,monitor And limit pressure overshoot to ensure Not exceeding the threshold At the same time, it is coupled with the perimeter control target to avoid the bad link shown in Table 1, which is pressure increase - perimeter increase - gap becomes interference - causing glue edge / detachment risk.

[0067] Molding clamping and transfer suppression module (transfer ring structure): The original 8 clamping block transfer rings in the molding machine blank clamping / transfer station are upgraded to The clamping block type transmission ring (preferably 12 full-size clamping blocks) forms a more uniform circumferential force distribution, suppressing the enhancement of specific harmonics (especially 8H) caused by the periodic disturbance of clamping; Figure 3 The comparison trend of the improvement of RFV8H by 8-block and 12-block structures is presented.

[0068] Uniformity testing and noise spectrum acquisition module: Performs uniformity testing on vulcanized tires and acquires... (may contain) and Simultaneously, the cavity noise spectrum was obtained under NVH test bench or road simulation conditions, and the actual noise level was determined. It is used for closed-loop determination and parameter recalibration.

[0069] Controller (PLC / Industrial Computer): Stores and manages data. , , , , , , , , The parameters such as limit values ​​are used to execute the logic corresponding to steps S1 to S5 of the claims, and to complete abnormal alarms, traceability and statistical analysis (such as pass rate, process capability index, customer complaint correlation, etc.).

[0070] III. Specific Technical Route for Implementing the Method of the Invention

[0071] This invention is not a single-point improvement, but rather incorporates the three elements of cavity noise formation—the inherent characteristics of the acoustic cavity, the transmission path, and the excitation source—into a unified, coordinated control chain. Its overall technical approach can be summarized as follows:

[0072] First chain: Natural frequency locked chain (weight / circumference → natural frequency stability)

[0073] By measuring the weight of the embryo and the convergence control of its distribution (such as controlling the weight deviation of the critical area of ​​the finished product within) Within (within), reduce the inherent frequency drift caused by equivalent quality fluctuations; by adjusting the embryo circumference Strict constraints (such as) mm), stabilizing the cavity volume and the prestress distribution of the tire carcass, thereby... around Stablize.

[0074] Second chain: Excitation source reduction chain (vulcanization pressure curve + molding clamping cycle → RFV8H decrease)

[0075] By using secondary shaping pressure Controlled ~ MPa, and further limit peak pressure overshoot. No more than MPa, reducing the unrecoverable uneven internal stress caused by overstretching, thereby weakening Harmonic excitation; simultaneously, by increasing the number of clamping blocks in the transfer ring to This makes the clamping force points more uniform, reduces clamping cycle disturbances, and suppresses the 8H source. Figure 2 and Figure 3 Improvement directions consistent with this chain are given.

[0076] The third chain: a data-driven closed-loop chain (test feedback → parameter write-back and locking).

[0077] by and As the outcome indicator, , , Using a clamping structure as a control mechanism, a closed loop of judgment-writeback-re-verification is formed, enabling the method to have mass production reproducibility and cross-batch stability.

[0078] IV. Detailed description of the specific implementation method of each step

[0079] 4.1 Step S1, Setting Targets and Limits

[0080] Step S1 is used to establish the control objectives, threshold system, and judgment criteria of this invention, and is usually performed when introducing new specifications, changing molds, updating formulas, or adjusting NVH targets; in the mass production stage, it can also be reviewed monthly or batch-by-batch. S1 includes the following sub-steps:

[0081] 1) Target frequency and allowable deviation settings

[0082] Based on the vehicle's NVH targets and customer complaint-sensitive frequency bands (see appendix) Figure 1 (Concentrated region of 200-250Hz) to determine the target peak frequency of cavity noise. and allowable deviation For example, for a 205 / 50R17 high-performance passenger car tire, it can be set to... Hz, Hz, to ensure the actual peak frequency It stabilizes within the range of 235±5Hz, thereby reducing the probability of entering the central region of sensitive frequency bands.

[0083] 2) Weight and weight deviation rate threshold setting

[0084] Set target weight Upper limit of weight deviation rate The weight deviation rate is defined as:

[0085] ;

[0086] in, This is the actual measured weight of the embryo. The target weight of the embryo. This refers to the weight deviation rate. Preferably, Take a value of 0.01 to 0.03, or control it based on the zonal weight deviation (tire crown / sidewall). As an engineering constraint.

[0087] 3) Perimeter and perimeter deviation threshold setting

[0088] Set target perimeter Upper limit of deviation from perimeter Preferred mm, so that the circumference fluctuation will not significantly change the cavity volume and the prestress distribution of the tire body.

[0089] 4) Setting of secondary shaping pressure and peak overshoot threshold

[0090] Set secondary shaping pressure and its permitted scope (Preferred) MPa MPa), and set the upper limit for pressure peak overshoot. Pressure overshoot is defined as:

[0091] ;

[0092] in, This represents the maximum value of the internal pressure curve during the secondary shaping stage. This is the set value for the secondary shaping pressure. This represents the pressure peak overshoot. (Optimal constraint) MPa.

[0093] 5) Setting the threshold for uniformity incentive index

[0094] set up Limit ,For example kgf is used to ensure that the intensity of the 8H excitation source is at a low level, thereby reducing the possibility of cavity resonance being excited from the source.

[0095] 4.2 Step S2, Acquisition and Determination of Natural Frequency Control Quantity

[0096] The core of step S2 lies in upgrading traditional quality control indicators (weight, circumference) into control quantities whose cavity noise natural frequency is predictable, determineable, and rewritable, thereby establishing the systematic collaborative control foundation of this invention. S2 is preferably implemented jointly by a weighing module, a circumference measurement module, a natural frequency prediction and evaluation module, and a controller, and can be specifically implemented as follows:

[0097] (a) Embryo weight Acquisition and preprocessing

[0098] 1) Data collection location and granularity

[0099] The optimal location for collecting tire blank weight data is at the tire blank removal station, using either a dynamic or static scale to achieve 100% weighing. To further control the uniformity of weight distribution, a zoned weighing strategy can be introduced: weighing key components of the tire blank (such as belt layer assembly, sidewall assembly, and tread assembly) separately before they are put into service, or indirectly achieving zoned weight control by monitoring the length and mass per unit length of each component.

[0100] 2) Data cleaning and anomaly removal

[0101] Weighing data may be affected by factors such as weighing platform vibration, foreign matter adhering to the tire blank, and ambient airflow. The controller can be set with a stable time window and a repeat weighing strategy, such as continuous sampling of the same tire blank at the same workstation. Next (such as) If the difference between the maximum and minimum values ​​exceeds the threshold (e.g., 2g), a retest or manual confirmation is prompted; if foreign matter is confirmed, it is removed and recorded.

[0102] 3) Determination of weight deviation rate

[0103] Actual measurement With the goal Compare the calculation formula (1) And make a classification judgment:

[0104] when The weight is acceptable; proceed to the circumference determination.

[0105] when If the weight is unqualified, the S3 write-back strategy is triggered (see S3 for details), and its influence on the predicted peak frequency offset is recorded.

[0106] (ii) Embryo circumference Data acquisition and pressure-gap correlation modeling

[0107] 1) Data Acquisition Strategy

[0108] Considering mass production efficiency and cost, the circumference measurement strategy can be adopted: stricter testing on the first piece + stricter testing for abnormalities + random sampling. The first tire blank of each molding machine must be measured every day; stricter testing is required when abnormal weight, abnormal vulcanization pressure, abnormal uniformity, or abnormal noise occurs; and random sampling is conducted on a steady-state batch basis (e.g., 1 piece out of every 50 pieces). For specifications that are highly sensitive to NVH, full inspection of key batches can also be implemented.

[0109] 2) Perimeter deviation determination

[0110] Calculate perimeter deviation and Compare:

[0111] when The perimeter is acceptable.

[0112] when If the perimeter is not up to standard, the S4 write-back strategy will be triggered (see S4 for details).

[0113] 3) Coupling relationship with vulcanization setting pressure (refer to Table 1)

[0114] Table 1: Experimental data on the effect of vulcanization setting pressure on the circumference of the tire blank and the gap between the tire blank and the mold.

[0115]

[0116] As shown in Table 1 and the data in Figure 1, when the molding pressure gradually increases from 0.06 MPa to 0.12 MPa, the circumference of the tire blank tends to increase (e.g., from 1916 mm to 1953 mm), and the gap between the tire blank and the mold gradually decreases from a positive gap to an interference fit (e.g., from 4.0 mm to -1.9 mm), with the risk of glued edges / detachment. This indicates that the circumference is not solely controlled by molding; excessively high vulcanization molding pressure or sharp peaks in the pressure curve can also cause excessive stretching of the tire blank, leading to an excessively large circumference and changes in cavity volume, ultimately causing natural frequency drift and structural defects. Therefore, this invention not only records in stage S2... Furthermore, it is preferred to record the mapping relationship between perimeter, pressure, and gap related to the vulcanization stage, providing a basis for the coordinated control of S4 and S5.

[0117] (iii) Predicting peak frequency Calculation and judgment

[0118] 1) The necessity and objectives of prediction

[0119] In mass production scenarios, relying solely on finished product noise test feedback is time-consuming and difficult to correct deviations in a timely manner. This invention establishes a prediction mechanism based on the tire blank's state and inherent frequency, enabling the risk of the tire blank entering a sensitive frequency band to be determined before vulcanization. This allows for the early writing back of molding / vulcanization settings, reducing batch drift.

[0120] 2) Implementation of the prediction model

[0121] Path A: Table lookup / piecewise linear mapping model

[0122] Establish two-dimensional or three-dimensional lookup table relationships based on historical production data, for example, using and As the independent variable, with The dependent variable is used to form a lookup table matrix or piecewise linear fit. The controller obtains... and Then, interpolation calculations were performed to obtain... This method is simple to implement, highly interpretable, and suitable for rapid project implementation.

[0123] Path B: Regression Model / Lightweight Machine Learning Model

[0124] When there is sufficient data, models such as multiple linear regression, ridge regression, or gradient boosting trees can be used to... Input is equal to the value of the input, and output is equal to the value of the output. Model training can be performed offline, with only the inference module deployed online. This approach is better able to capture non-linear relationships.

[0125] 3) Prediction frequency deviation determination and risk classification

[0126] calculate and Compare:

[0127] Low risk: Proceed to the next step;

[0128] Medium risk: It is recommended to prioritize writing back the weight or perimeter settings;

[0129] High risk: This triggers a forced write-back and allows for stricter monitoring of the embryo (such as mandatory subsequent uniformity checks and noise bench retests).

[0130] 4) Attribution principles for judgment and write-back trigger logic

[0131] To avoid blind adjustments, S2 optimization incorporates attribution rules: when Deviation First, determine the deviation and , Correlation:

[0132] like Smaller and When entering a sensitive area (e.g., the pattern of shifting towards low / high frequencies is determined by historical data), S3 is triggered first.

[0133] like Larger / Smaller The offset changes in line with the perimeter, triggering S4 first.

[0134] like and All qualified If the deviation persists, it indicates an abnormality in the vulcanization pressure curve or increased clamping disturbance. Prioritize checking S5. Overshoot and transfer loop state.

[0135] Through the above S2 step, the present invention achieves the preliminary identification of inherent frequency risks and establishes a unified data base for weight, perimeter, pressure, clamping, and noise, providing an executable basis for subsequent closed-loop control.

[0136] 4.3 Step S3, Weight Closed-Loop Correction

[0137] Step S3 is used to upgrade weight control from result verification to process write-back. The key to its implementation lies in: once the weight deviation rate is detected... If the deviation exceeds the limit or the predicted frequency deviation is related to the weight deviation, the upstream process parameters such as extrusion and bonding should be adjusted immediately to bring the subsequent preform weight back to the target range, thereby stabilizing the equivalent quality and reducing the natural frequency drift.

[0138] 1) Write-back objects and adjustment amounts

[0139] Weight deviations typically originate from tread extrusion, sidewall extrusion, belt layer film, or bonding overlap. Data that can be rewritten may include: extruder screw speed, traction speed, and die clearance, which alter the amount of adhesive supplied per unit length; bonding tension, overlap length, and cut length of the laminator; and target thickness values ​​for critical components or online thickness measurement closed-loop parameters.

[0140] 2) Write-back rules

[0141] when At that time, the controller calculates .like (If heavier), reduce the amount of adhesive supplied per unit length or reduce the overlap proportionally; if If the material is too light, then increase the glue supply or the overlap. The proportionality coefficient can be determined from historical process capabilities; for example, the change in extrusion parameters corresponding to each 1g / strip adjustment in glue supply. This can form an experience mapping or be updated online through self-learning.

[0142] 3) Zoned weight control (preferred)

[0143] To more effectively control the inherent frequency, it is preferable to implement zoned weight constraints on the tire crown and sidewall. For example, the weight deviation in the tire crown area is controlled within a certain range. The inner portion can more directly affect the equivalent mass distribution of the tire structure in the cavity coupling mode, thereby... More stable. This can be achieved by weighing or monitoring the length and quality of the tread, belt layer rubber, and sidewall rubber separately.

[0144] Step S4, circumference and shaping pressure are adjusted in tandem.

[0145] The core innovation of step S4 lies in establishing a synergistic relationship between perimeter control and vulcanization pressure control, avoiding the disconnect between the traditional approach where molding only manages perimeter and vulcanization only manages pressure. As shown in Table 1, changes in setting pressure not only affect uniformity excitation but also significantly alter the tire blank perimeter and the tire blank-mold gap, thus simultaneously impacting the acoustic cavity volume, natural frequency, and structural defect risk. Therefore, S4 uses perimeter deviation as a trigger point, simultaneously writing back to both the molding and vulcanization ends to stabilize the acoustic cavity structure and transmission path.

[0146] (I) Specific implementation of the correction of the circumference of the forming end

[0147] 1) Analysis of the sources of perimeter deviation

[0148] The deviation in the tire carcass circumference may originate from: errors in the molding drum diameter, molding tension settings, fabric cutting length and overlap, and differences in elastic shrinkage due to tire carcass temperature. S4 preferably employs a dual-path correction method combining equipment calibration and process settings.

[0149] Equipment calibration: Periodically verify the diameter of the forming drum and the concentricity of the drum surface;

[0150] Process settings: Adjust circumferential tension, cutting length, and overlap, etc.

[0151] 2) Calculation and execution of write-back volume

[0152] calculate .like (If the perimeter is too large), it is preferable to reduce the forming tension or reduce the cutting length; if If the perimeter is too small, increase the tension or the cutting length accordingly. To avoid over-adjustment causing oscillations, a proportional-integral progressive correction can be used: correct only the following at a time. A certain proportion (such as 30% to 50%) is used, and the trend of the next 3 to 5 embryos is observed before further adjustments are made.

[0153] 3) Perimeter control and acoustic cavity stability

[0154] Perimeter deviation alters the internal cavity volume and prestress distribution of the tire carcass after vulcanization, thus affecting the cavity's natural frequency. By... (Preferred 5mm) as a hard constraint can significantly reduce Batch dispersion, and reduce cavity noise peaks falling into the surrounding area. Figure 1 The probability of the sensitive frequency band shown.

[0155] (ii) Secondary setting pressure at the vulcanization end Coordinated correction with perimeter (in conjunction with engineering constraints in Table 1)

[0156] 1) Why is collaboration necessary?

[0157] Table 1 shows that increased molding pressure leads to increased tire circumference, reduced clearance, and even interference, increasing the risk of rubber edge / separation. If the circumference is reduced only at the molding end, but the vulcanization pressure remains too high or has spikes, the tire may still be stretched during vulcanization, thus negating the molding control effect and even causing structural defects. Therefore, S4 stipulates that when the circumference deviation exceeds the limit or... When the deviation is related to the perimeter, it should be adjusted synchronously. This allows the overall molding circumference and vulcanization stretching to be controlled.

[0158] 2) Collaborative Correction Strategy

[0159] when When the gap is too large or there is a risk of over-excess: it is preferable to adjust downwards. to The low to medium values ​​(e.g., 0.06 MPa) are further constrained in S5. Overshoot prevents the actual pressure curve from spiked, causing further stretching.

[0160] when When the size is too small but there are risks of insufficient mold filling and pattern forming: it can be done within no more than Fine-tuning under the premise Meanwhile, the circumference deviation is addressed by rewriting the tension at the forming end, thus avoiding reliance on pressurization for forced forming.

[0161] 3) Gap constraint (preferred)

[0162] Based on the mold design clearance (e.g., the design distance of 3.5mm in Table 1), a process safety window can be set: blank-mold clearance. Should be kept ,in Avoid over-excess (e.g.) mm), Avoid excessive gaps that could lead to insufficient mold filling (e.g.) mm). When found through mapping in Table 1 or online estimation. Approaching When, priority should be given to lowering and restrictions .

[0163] (iii) Link step S4 with target locking using the inherent frequency.

[0164] Step S4 not only aims for a satisfactory perimeter, but also... Stable. Therefore, after step S4 is executed, the controller should be recalculated or updated. and judge Whether convergence has occurred. If the perimeter is within acceptable limits but the frequency still deviates, it indicates that the weight distribution or the excitation source reduction measures in step S5 need to be checked.

[0165] Through step S4, the present invention achieves unified control of acoustic cavity structure stability, transmission path stability, and process safety window: it avoids perimeter drift and defects caused by excessive pressure, and incorporates the influence of perimeter fluctuation on the natural frequency into the closed loop, thereby reducing cavity noise from a system perspective.

[0166] Step S5, 4.5: Excitation source reduction, process constraints, and feedback loop closure.

[0167] Step S5 is a key step in this invention to reduce the excitation source energy at the source and form a closed-loop recalibration. It includes two core measures: peak overshoot constraint of the vulcanization secondary setting pressure curve and suppression of perturbation during the molding clamping cycle. Clamping block transfer ring); and with and As a result feedback, it enables parameter updates and continuous stability.

[0168] (I) Closed-loop control and peak overshoot constraint of the secondary setting pressure curve of vulcanization

[0169] 1) Problem Mechanism

[0170] In mass production, even if set Even at a certain value, the actual pressure curve may still exhibit transient overshoot or spikes (e.g., valve response hysteresis, gas source fluctuations, improper control parameters), leading to short-term excessive stretching of the tire cords. This overstretching, after cooling and setting, solidifies into irreversible internal stress unevenness, significantly amplifying harmonic components in the uniformity (including...). , (etc.), which become a strong excitation source for cavity resonance. Figure 2 The experimental trend shows that when the setting pressure is reduced from 0.08 MPa to 0.06 MPa, A significant decrease of about 50% can occur, which is consistent with the mechanism described above.

[0171] 2) Expression of control objectives and constraints

[0172] Step S5 requires: During the secondary shaping stage, ensure... In And the pressure peak overshoot satisfies:

[0173] ;

[0174] in, This represents the maximum value of the pressure curve during the secondary shaping stage. For setting value, To allow for an overshoot limit (preferably 0.02 MPa).

[0175] 3) Closed-loop implementation method

[0176] Sensor sampling: The pressure sensor acquires pressure curves at a sufficient sampling frequency (e.g., 50–200 Hz) to ensure the capture of transient spikes;

[0177] Controller Algorithm: The controller performs real-time peak detection and prediction of the pressure curve, and can adopt a threshold trigger + sliding window maximum value strategy;

[0178] Actuator adjustment: The airbag intake and exhaust are controlled by a proportional valve / solenoid valve to quickly reduce the pressure back to the set trajectory; if necessary, the PID parameters are adjusted to suppress overshoot;

[0179] Alarm and interlock: If continuous Next (such as) )Appear This will trigger an alarm and can be linked to a degradation strategy, such as forcibly degrading the system. The pressure was lowered to 0.06 MPa and subsequent uniformity testing was tightened.

[0180] 4) Coordination with perimeter control (step S4)

[0181] When S4 has been downgraded due to its large circumference. At that time, S5 further restricted This prevents the actual pressure spikes from stretching the tire blank again, avoiding the risk of the gap shown in Table 1 changing from positive to negative and causing edge / detachment. This creates a dual constraint of set value + curve shape, rather than just constraining the set value.

[0182] (ii) Suppression of disturbances during the molding and clamping cycle: Clamping block transfer ring

[0183] 1) Why does the clamping structure introduce 8H excitation?

[0184] If the number of clamping points is small (e.g., 8) or the force is uneven during the clamping and transfer process after the tire blank is formed, periodic deformation and residual stress distribution will form in the circumferential direction of the tire blank. This periodic disturbance can manifest as specific harmonic enhancement in the subsequent vulcanization and shaping and the uniformity of the finished product, especially on some specification platforms, where it is more significantly correlated with 8H. Figure 3 The comparison shows that, for specifications such as 205 / 50R17, using a 12-piece structure compared to an 8-piece structure can... Significant reduction (example trend: from about 1.2 kgf to about 0.5 kgf).

[0185] 2) Key points of structural implementation

[0186] Number of clamping blocks satisfy Preferred ;

[0187] The clamping blocks are evenly distributed along the circumference to ensure that the force-bearing points are spaced at equal angles.

[0188] Full-size clamping blocks are preferred to increase the clamping contact area and reduce local indentations;

[0189] The clamping force is calibrated to ensure that the difference in clamping force between each clamping block does not exceed a set threshold (e.g., ±5%), thus avoiding a failure mode with multiple but uneven clamping points.

[0190] 3) Considerations for process cycle time and compatibility

[0191] Upgrading the transfer rings requires compatibility with the molding machine's cycle time and blank size range. A modular approach is preferred, allowing the same machine to replace 12 transfer rings of corresponding diameters for different specifications while maintaining the required clamping stroke and centering accuracy.

[0192] (III) Collection of Results Indicators and Closed-Loop Feedback Updates

[0193] 1) Uniformity test and determination

[0194] After vulcanization, the uniformity of the tires was tested, and the results were measured separately. and And the average value can be taken as :

[0195] ;

[0196] in, The amplitude value of 8H was obtained by clockwise testing. The amplitude value at 8H is obtained from the counterclockwise test. This is the overall 8H amplitude. If... If the excitation source reduction is insufficient, it is necessary to backtrack the pressure curve overshoot and clamping structure status in S5. At the same time, S3 and S4 can be backtracked to check whether there is boundary drift in weight / circumference.

[0197] 2) Noise spectrum acquisition and determination

[0198] Collect cavity noise spectra in NVH test benches, vehicle road tests, or acoustic laboratories to determine the actual .like This indicates insufficient natural frequency locking, requiring a backtracking of the weight and circumference control from S2 to S4. If necessary, adjustments should be made to... The prediction model is recalibrated.

[0199] 3) Parameter update and write-back strategy (continuously improved)

[0200] When any of the following conditions are met:

[0201] ;

[0202] ;

[0203] Controller update , , At least one of the following, and return to execute S3 and S4. The preferred update principle is:

[0204] If the main cause of the frequency shift is weight drift, then fine-tune... and its partition objectives;

[0205] If the main cause of the frequency shift is perimeter drift or pressure-perimeter coupling as shown in Table 1, then adjust... And optimize and Control parameters;

[0206] like If the weight / circumference is normal but the abnormality is not, the priority should be to check the balance of the clamping force of the transfer ring and the overshoot of the vulcanization pressure curve.

[0207] Through step S5, the present invention realizes a closed-loop system of setpoint control, process curve constraint, structural disturbance suppression, and result feedback update, which can stably reduce the 8H excitation source and lock the peak frequency of cavity noise under mass production conditions, and ultimately achieve a systematic reduction in cavity noise complaints.

[0208] V. Specific Application Examples

[0209] The following are three specific application examples and comparative examples. The experimental design and data are designed to closely resemble real-world tire manufacturing and laboratory verification scenarios, and are accompanied by figures / tables (see attached figures). Figure 1 Table 1 Figure 2 , Figure 3 The pattern shown is consistent with the characteristics of this invention, which is used to demonstrate the systematic suppression effect of the invention on cavity noise by synergistically controlling the natural frequency, circumferential size / stiffness uniformity and RFV8H excitation source.

[0210] (I) General test conditions and detection methods

[0211] 1. Test subjects and batch settings

[0212] Test tire specifications: 195 / 65R15 (GTRcomfort platform) and 205 / 50R17 (high-performance passenger car tire platform) were each selected from one typical production line for verification.

[0213] For each group (example / comparative example), at least n=30 tires were produced for statistical analysis. Among them, n_U=20 tires were selected for uniformity testing, and n_N=10 tires were selected for cavity noise bench / semi-anechoic chamber spectrum testing. If conditions permit, the noise test can be extended to the whole vehicle road NVH condition.

[0214] 2. Definition of key parameters

[0215] Embryo weight: Target weight: Weight deviation rate: in This represents the weight deviation rate.

[0216] Embryo circumference: Target perimeter: Perimeter deviation: .

[0217] Secondary setting pressure setting value: Peak pressure during the secondary shaping stage: Peak overshoot: in This refers to the pressure peak overshoot.

[0218] Radial force variation eighth harmonic: and record , Overall value:

[0219] ;

[0220] Cavity noise peak frequency: Target peak frequency: Allowable deviation: .

[0221] Peak sound pressure level (or equivalent) of cavity noise: The unit is dB(A) or dB (the same weights should be used and the test conditions should be consistent).

[0222] 3. Testing equipment and methods

[0223] Cartridge weight: Static electronic scale at the molding line station, resolution 0.5g; each cartridge is weighed once, and re-measured twice if there is an abnormality.

[0224] Embryo circumference: Use a laser circumference meter or circumference tape / ring fixture, repeat the measurement twice and take the average.

[0225] Vulcanization pressure curve: The sampling frequency of the pressure sensor of the vulcanizing machine is ≥50Hz. Record the entire curve during the secondary setting stage and extract the curve. .

[0226] Uniformity: measured by dynamic averaging tester , .

[0227] Cavity noise: Tire cavity noise test bench (tire and rim assembly, under specified load, inflation pressure and speed), microphone array sampling, FFT to obtain the spectrum, extraction and .

[0228] (II) Example 1 (195 / 65R15 platform)

[0229] 1. Purpose

[0230] Verification: On the 195 / 65R15 platform, the secondary shaping pressure was controlled according to the present invention. The pressure should be between 0.05 and 0.07 MPa, and peak overshoot should be limited. At MPa, the tire blank circumference is stable, the mold clearance remains positive, and The cavity noise decreased significantly; at the same time, the trend shown in Table 1 was reproduced: increased pressure → increased circumference → smaller gap / interference → risk of rubber edge.

[0231] 2. Process Setup

[0232] Target perimeter: mm; Maximum perimeter deviation: mm.

[0233] Secondary setting pressure: MPa; Pressure range: MPa MPa; Overshoot limit: MPa.

[0234] Transfer ring structure: Maintain the original production line configuration (this example focuses on verifying the vulcanization pressure link), and the number of clamping blocks is not a variable.

[0235] Target frequency: Hz; Hz (used for statistical determination).

[0236] 3. Experimental data (statistical results for n=30)

[0237] Table 2 Summary of key processes and results data in Example 1 (195 / 65R15)

[0238]

[0239] 4. Results Analysis

[0240] 1) Pressure-perimeter coupling: Comparative example A in When the pressure is increased by MPa and the overshoot is more pronounced, the mean perimeter increases significantly, the dispersion increases, and the gap approaches zero, resulting in the risk of glue edge; this is consistent with the pattern in Table 1 where pressure increases → perimeter increases → gap decreases / interference.

[0241] 2) Excitation source reduction: Example 1 controls and restrictions , The mean value decreased to 0.31 kgf, a decrease of approximately 50% compared to control sample A. Figure 2 The pattern of a significant decrease in RFV8H is consistent with the decrease in pressure.

[0242] 3) Noise reduction: Example 1 The frequencies are concentrated around 235Hz and have small dispersion, with a significantly reduced proportion of the sensitive band. The average decrease of about 5dB indicates that the effect is achieved by simultaneously stabilizing the natural frequency and reducing the excitation source.

[0243] (III) Example 2 (205 / 50R17 platform)

[0244] 1. Purpose

[0245] Verification: Upgrading the forming machine's transfer ring from 8 clamping blocks to 12 full-size clamping blocks significantly reduces the impact of clamping cycle disturbances. This weakens the cavity resonance excitation at its source and reduces the peak sound pressure level of the cavity noise; reproducing Figure 3 The trend is that 12 pieces are better than 8 pieces.

[0246] 2. Process Setup

[0247] The experiment fixed the secondary setting pressure of vulcanization at... MPa, and maintain MPa (to avoid pressure becoming a distracting factor).

[0248] The only variable for comparison is the number of blocks held by the transfer ring:

[0249] Comparative Example B: 8 clamping block transfer rings (original configuration)

[0250] Example 2: 12 full-size clamping block transfer rings (this invention)

[0251] 3. Experimental data (statistical results for n=30)

[0252] Table 3 Comparison of results between Example 2 and Comparative Example B (205 / 50R17)

[0253]

[0254] 4. Results Analysis

[0255] 8H excitation significantly reduced: simply changing the number of clamping blocks is sufficient. The mean decreased from 0.97 to 0.46 kgf, a drop of approximately 53%, compared to... Figure 3 The consistent trend indicates that the clamping period disturbance has been effectively suppressed.

[0256] Noise synchronization improvement: The average decrease was approximately 3.9 dB, and The decrease in discreteness indicates that, with the natural frequency remaining essentially unchanged (and the perimeter being similar), weakening the excitation source can significantly reduce the intensity of resonance excitation.

[0257] (iv) Example 3

[0258] 1. Purpose

[0259] Verification: When the triple measures of this invention are implemented simultaneously (inherent frequency locking chain + transmission path stabilization chain + excitation source reduction chain), the risk of customer complaints in the sensitive frequency band of 200-250Hz can be significantly reduced, as shown in the following ways:

[0260] Stable at ;

[0261] Significantly decreased and the pass rate increased;

[0262] The peak sound pressure level of the cavity noise decreased and stabilized in batches.

[0263] 2. Process settings (205 / 50R17)

[0264] Target frequency: Hz, Hz.

[0265] Weight control: settings kg (example), control And control the weight deviation of the tread / sidewall zones within .

[0266] Perimeter control: mm, mm.

[0267] Vulcanization control: MPa MPa MPa MPa.

[0268] Transfer loop: Full-size clamping block.

[0269] Comparative Example C: Only traditional process control is performed (weight sampling, perimeter not linked, ... Set to 0.08MPa and do not constrain overshoot, 8 transfer loops).

[0270] 3. Experimental data (statistical results for n=30)

[0271] Table 4 Comparison of full-link collaboration in Example 3 and Comparative Example C (205 / 50R17)

[0272]

[0273] 4. Results Analysis

[0274] The natural frequency is locked: Comparative C Large dispersion (standard deviation 12.1Hz) and mean deviating from the target; Example 3 Concentrated around 235Hz, the pass rate increased to 86%, indicating that after weight and circumference were used for natural frequency control, the probability of drifting into the sensitive area could be significantly reduced.

[0275] The excitation source is significantly reduced: Example 3 The mean value decreased from 0.88 to 0.38 kgf, and the pass rate increased significantly, indicating that the pressure window / overshoot constraint and the 12-block clamping structure have a superimposed effect on the reduction of the 8H excitation source.

[0276] Noise amplitude and stability are improved simultaneously: The average energy reduction was approximately 5.6 dB, and the standard deviation decreased from 2.4 to 1.3 dB, indicating not only greater quietness but also improved stability. The relative peak energy in the sensitive frequency band decreased to 0.42, directly corresponding to the attached... Figure 1 The risk of customer complaints in the indicated frequency bands has decreased.

[0277] 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.

[0278] 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.

[0279] 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.

[0280] 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.

[0281] 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.

[0282] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0283] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0284] Computer-readable media include both permanent and non-permanent, removable and non-removable media that can store information by 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 for adjusting the natural frequency and excitation source to improve tire cavity noise, characterized in that, The method includes the following steps: S1, Target peak frequency of tire cavity noise and allowable deviation And determine the target embryo weight corresponding to the target peak frequency. Target perimeter Secondary shaping pressure setting value and the eighth harmonic limit of radial force variation S2, The actual weight of the tire blank is collected after the tire is formed. and measured perimeter and based on and The peak frequency of cavity noise in the tire-air system is predicted, and the predicted peak frequency is obtained. ;when Compared to The deviation exceeds Furthermore, when related to weight deviation, the weight deviation rate of the embryo can be adjusted by regulating the extrusion and bonding process parameters. Keep within the preset range; when Compared to The deviation exceeds Furthermore, when related to circumference deviation, the circumferential tension during molding and the secondary shaping pressure are adjusted in a coordinated manner. This causes the embryo's circumference to deviate. Controlled within a preset range; S3, during the vulcanization process, the pressure curve of the secondary setting stage is monitored and controlled to ensure that the pressure peak is within the preset range. With secondary shaping pressure setting value The difference between them does not exceed a preset threshold. At the same time, in the molding clamping and transfer process, a clamping block type transfer ring with no less than 12 clamping blocks is used to weaken the circumferential periodic disturbance. And after vulcanization, the radial force variation of the tire is detected by the eighth harmonic. ,when Exceeding the stated limit Or the actual peak frequency of cavity noise Deviation Exceed Update , or At least one of the above and return to execute S2 to systematically reduce tire cavity noise.

2. The method according to claim 1, characterized in that, In step S1, the target peak frequency The preset peak frequency of cavity noise allows for a deviation of [missing information]. The allowed frequency width for fluctuation of the peak frequency; and includes the following steps: Determine the target weight for the embryo, including the target weight. Upper limit of weight deviation rate The actual weight of the embryo was The weight deviation rate is ; Determine the target circumference of the embryo, including the target circumference. Upper limit of deviation from perimeter The measured circumference of the embryo was 100 mm. The perimeter deviation is ; Determine the vulcanization setting pressure control target, including the secondary setting pressure setpoint. Lower limit of pressure range and upper limit The secondary shaping pressure setting value The pressure inside the air bladder applied to the inner surface of the tire blank during the secondary shaping stage of vulcanization, and meeting the following requirements. ; Determine the upper limit of pressure peak overshoot The maximum value of the internal pressure curve during the secondary shaping stage is The peak pressure overshoot is ; And determine the eighth harmonic limit of radial force variation. ,in This is the amplitude of the eighth harmonic of the radial force variation during the tire uniformity test.

3. The method according to claim 1, characterized in that, In step S2, each embryo is weighed to obtain the weight. And perform a perimeter measurement to obtain and according to , With the target peak frequency Establish or invoke the inherent frequency control relationship to obtain the predicted peak frequency corresponding to the embryo. Among them, the predicted peak frequency The peak frequency of cavity noise is calculated from the tire blank state in the tire-air coupling system. When the weight deviation rate is greater than Or predict peak frequency Deviation Exceed Furthermore, when its deviation is related to weight deviation, it is based on the difference. The amount of adhesive supplied per unit length, component thickness, or bonding position in the extrusion and bonding processes are adjusted to ensure that the weight deviation rate of the subsequent preform is no greater than [value missing]. ; When the perimeter deviation is greater than Or predict peak frequency Deviation Exceed Furthermore, when its deviation is related to the perimeter deviation, it is based on the difference. The circumferential tension or forming drum size in the molding process is corrected, and the secondary setting pressure setting value is corrected simultaneously. This ensures that the circumference deviation of the subsequent embryo is no greater than [a certain value]. And maintain .

4. The method according to claim 1, characterized in that, In step S2, the upper limit of the weight deviation rate Pick to Furthermore, the weight deviation of key areas of the tire blank or finished tire, including the crown and sidewall, is controlled within the target weight of the corresponding area. within; And / or, the upper limit of the perimeter deviation for ; And / or, the lower limit of the pressure range for Upper limit of pressure range for And the upper limit of the pressure peak overshoot for Or smaller.

5. The method according to claim 1, characterized in that, The number of clamping blocks of the clamping block type transfer ring for Furthermore, the clamping block is a full-size clamping block, which ensures that the tire blank forms at least 12 uniform force points along the circumference during clamping and transfer.

6. The method according to claim 1, characterized in that, The uniformity test includes tests in both clockwise and counterclockwise directions, yielding results respectively. and And the average of the two is taken as the value of the two. .

7. The method according to claim 1, characterized in that, The inherent frequency control relationship is a mapping model or lookup table model established based on historical samples, and the historical samples at least include the measured weight of the embryo. Measured circumference of the embryo Secondary shaping pressure setting value With the corresponding actual peak frequency Used to output predicted peak frequency .

8. A system for improving tire cavity noise by adjusting the natural frequency and excitation source, characterized in that, The system is used to implement the method according to any one of claims 1-7, comprising: The weighing module is used to obtain the measured weight of the embryo. ; The circumference measurement module is used to obtain the actual circumference of the embryo. ; The vulcanization and setting pressure control module, including a pressure sensor and an actuator, is used to set the secondary setting pressure value. And obtain the pressure peak value of the internal pressure curve during the secondary shaping stage. ; The clamping block type transfer ring has the following number of clamping blocks: and ; The uniformity test module is used to measure the eighth harmonic of the radial force variation of the tire. ; The noise spectrum acquisition module is used to acquire the cavity noise spectrum and determine the actual peak frequency. ; Controller, stores target peak frequency Allowable deviation Target weight Upper limit of weight deviation rate Target perimeter Circumference deviation upper limit Lower limit of pressure range and upper limit Pressure peak overshoot limit and the eighth harmonic limit of radial force variation And configured to perform steps S1 to S5 of the method according to any one of claims 1-7.

9. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by a processor, they implement the steps of the method described in any one of claims 1-7.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by a processor, they implement the steps of the method described in any one of claims 1-7.

Images