A structural design method for solving low-frequency noise of passenger car tire

Abstract

The application relates to a structure design method for solving low-frequency noise of a passenger vehicle tire, and relates to the technical field of tires. The diameters of sample tire blanks before vulcanization and after inflation, the inflation rate a before vulcanization, the inflation rate b after vulcanization, the inflation rate change degree c before and after vulcanization, and tire noise parameters after vulcanization are collected. Sample tire blanks with tire noise parameters meeting design requirements are screened out as low-noise samples, qualified intervals of a, b and c are set based on the low-noise samples, and the qualified intervals are set at the same time. Tire blanks to be vulcanized, which meet the corresponding qualified intervals of a, b and c, are vulcanized. The application solves the problems that the circumferential mass distribution is uneven, the structural density difference is too large, the generation of inherent vibration frequency of the tire is effectively inhibited, the tire and the vehicle body structure are avoided from resonating, and the low-frequency vibration and noise induced and transmitted by the uneven tire structure during driving are significantly reduced.

Description

Technical Field

[0001] This invention relates to the field of tire technology, and in particular to a structural design method for solving low-frequency noise in passenger car tires. Background Technology

[0002] With breakthroughs in lithium battery technology, the range anxiety problem of electric vehicles has been solved. Electric vehicles have rapidly gained popularity due to their simple electric system structure, long maintenance cycles, low costs, electricity prices far lower than gasoline prices, quiet operation, and zero emissions. Since electric vehicles lack an internal combustion engine, the high-frequency noise of the drive motor is much lower than that of the engine. This makes tire noise and wind noise, which were previously masked by engine noise in gasoline vehicles, the main noise sources in electric vehicles.

[0003] In recent years, to effectively control low-frequency tire noise, a common approach in the industry is to address the noise at its source, such as combining porous materials with resonant sound-absorbing structures to attenuate tire noise. Related research has also confirmed that embedding optimized sound-absorbing materials inside the tire or adding specialized noise-reducing structures to the rim can reduce the level of low-frequency noise radiated by the tire to some extent.

[0004] However, existing technologies typically require attaching specialized sound-absorbing materials to the inside of the tire or the surface of the rim. This can lead to a series of problems for consumers, such as the sound-absorbing material peeling or falling off over long-term use, and the difficulty in repairing it once damaged. For manufacturers, adopting such solutions means investing in additional production equipment and purchasing specific materials, increasing production costs and potentially impacting production efficiency. Therefore, there is an urgent need for a more reliable, durable, and easy-to-implement low-frequency noise control structure design. Summary of the Invention

[0005] To address the shortcomings of related technologies, this invention provides a structural design method for solving low-frequency noise in passenger car tires. This method eliminates the need for additional noise reduction components, directly controlling the tire's expansion at different production stages from the core process of tire molding to vulcanization. This fundamentally reduces problems such as uneven circumferential mass distribution and excessive structural density differences caused by uneven expansion of different parts of the tire during vulcanization. This effectively suppresses the generation of the tire's inherent vibration frequency, preventing resonance with the vehicle body structure, and ultimately significantly reducing low-frequency vibrations and noise induced and transmitted by structural inhomogeneity during tire operation.

[0006] This invention provides a structural design method for solving low-frequency noise in passenger car tires, comprising the following steps: S1, determining the maximum diameter of the vulcanizing cavity of the tire vulcanizing mold through actual measurement or the instruction manual of the tire vulcanizing mold. ; Multiple pre-vulcanized tire blanks were selected as sample pre-vulcanized tire blanks, and their structural parameters were collected. These structural parameters included the outer diameter of the tire blank skeleton. Diameter after inflation before vulcanization 1. Expansion rate before vulcanization (a), expansion rate after vulcanization (b), degree of change in expansion rate before and after vulcanization (c), tire noise parameters after vulcanization; tire noise parameters include the average noise energy or effective sound pressure RMS during the test period, and the highest instantaneous sound pressure level MAX recorded during the test period. The outer diameter of the tire body after the airtight layer and the tire carcass are sequentially applied to the bonding drum of the tire forming machine; a=( - )÷ ×100%; b=( - )÷ ×100%; c = (ab) ÷ b; Select embryos with RMS less than a set threshold A and MAX less than a set threshold B as low-noise samples, and set qualified intervals a, b, and c based on the low-noise samples respectively. Based on design requirements The acceptable range; S2. Before embryo vulcanization, select Tire blanks that meet the corresponding qualified range are used as pre-cured tire blanks, based on the pre-cured tire blanks... Calculate a, b, and c, and select the tire blanks that meet the corresponding qualified ranges for vulcanization; tire blanks that do not meet the corresponding qualified ranges are returned to the molding process for reshaping or are regarded as scrap tire blanks.

[0007] In some embodiments, the acceptable range for a is 2.0% to 4.5%; the acceptable range for b is 2.0% to 4.5%; and the acceptable range for c is -0.2 to 0.2.

[0008] In some of these embodiments, in S1 and S2, The derivation yields:

[0009] Where e is a preset constant obtained through experiments; f is the thickness of the tread reinforcement structure applied to the tire carcass, obtained through actual measurement or design drawings; the tread reinforcement structure includes the belt layer, the crown layer and the tread.

[0010] In some embodiments, the value of e ranges from 0.985 to 0.995.

[0011] In some embodiments, the belt layer is composed of steel wire cord and rubber calendering composite, the included angle between the cord and the tire radial direction is 21°~33°, the diameter of the belt layer cord is 0.4mm~0.8mm, and the thickness of a single belt layer is 0.8mm~1.4mm; the tread reinforcement structure has two belt layers, and the cords of the two belt layers are inclined in opposite directions; The crown layer comprises a film layer consisting of cords wound around the tire circumference, a coating layer enclosing the film layer, and a rubber layer enclosing the coating layer; the cords of the crown layer are uniformly wound around the surface of the outermost belt layer, and the tension of the crown layer cords is controlled at 10N~50N during the winding process; the diameter of the crown layer cords is 0.5mm~0.9mm, and the thickness of the crown layer is 0.7mm~1.3mm; the crown layer cord material includes aramid material, nylon material, or a composite reinforcing material made of aramid blended with other high-performance fibers.

[0012] In some embodiments, S1 further includes transferring multiple low-noise samples... and The design pattern depth obtained from the design drawings is then substituted into the following formula to calculate the low-noise samples. : = 2ASD+ ; ASD represents the design pattern depth, which is obtained from the design drawings; S2 also includes the embryo to be vulcanized. ASD and The following relationship must be satisfied: = 2ASD+ ; in, Represents multiple The mean.

[0013] In some of these embodiments, The value range is -8mm to 8mm.

[0014] In some embodiments, S1 further includes measuring the tread thickness of the sample tire blank during assembly, and substituting the tread thickness and designed tread depth of multiple low-noise samples into the following formula to calculate the tread thickness of multiple low-noise samples. : h=ASD

[0015] Where h is the measured tread thickness and ASD is the designed tread depth, obtained from the drawings; S2 also includes that h and ASD of the tire blank to be vulcanized must satisfy the following formula: h=ASD

[0016] in, Represents multiple The mean.

[0017] In some of these embodiments, The value range is -1mm to 3mm.

[0018] In some embodiments, during the tire embryo forming process, the airtight layer, tire body, belt layer, crown belt layer and tread are first assembled in the radial direction of the tire in an uninflated state, and then the sidewall airtight layer, tire body, bead and sidewall are assembled in an inflated state.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This method requires no additional noise reduction components. It directly controls the expansion degree of the tire in different production processes from the core process of tire molding to vulcanization. It fundamentally reduces problems such as uneven circumferential mass distribution and excessive differences in structural density caused by uneven expansion of different parts of the tire during vulcanization. This effectively suppresses the generation of the tire's inherent vibration frequency and avoids resonance with the vehicle body structure. Ultimately, it significantly reduces the low-frequency vibration and noise induced and transmitted by the tire's structural inhomogeneity during driving. Consumers do not need to bear additional usage and maintenance costs. It eliminates the possibility of additional noise reduction components falling off and being damaged at the source, and greatly improves the reliability and durability of low-noise tires during use.

[0020] 2. This method relies entirely on the existing structural parameter control process in the conventional tire production process to achieve noise control. It does not require manufacturers to invest in additional special production equipment or purchase exclusive noise reduction materials. It is fully compatible with existing mature tire production lines and will not negatively affect the original production efficiency. The entire method has a clear logic and is easy to implement. The parameter verification process is well-defined and will not introduce additional quality control blind spots. It can be directly replicated and applied to the production control process of various passenger car tires to achieve large-scale low-noise tire production output. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 A flowchart illustrating the structural design method for resolving low-frequency noise in passenger vehicle tires in a specific embodiment of this application; Figure 2 The structural parameters of the sample embryo in the specific embodiments of this application; Figure 3 This is a diagram showing the test results of tire noise parameters of the sample embryo in a specific embodiment of this application; Figure 4 In the specific implementation of this application A schematic diagram; Figure 5 In the specific implementation of this application A schematic diagram; Figure 6 This is a schematic diagram of the tread reinforcement structure in a specific embodiment of this application; Figure 7 This is a schematic diagram illustrating the tire sidewall structure in a specific embodiment of this application.

[0022] In the diagram: 1. Belt layer; 3. Crown layer; 4. Tread; 5. Airtight layer; 6. Carcass; 7. Triangle rubber; 8. Sidewall. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] In the description of this invention, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] like Figure 1-7 As shown, in an illustrative embodiment of a structural design method for solving low-frequency noise in passenger car tires according to the present invention, the structural design method for solving low-frequency noise in passenger car tires includes the following steps: S1, by actual measurement or the instruction manual of the tire vulcanizing mold, the maximum diameter of the vulcanizing inner cavity of the tire vulcanizing mold is determined. ; Multiple pre-vulcanized tire embryos were selected as sample pre-vulcanized tire embryos, and their structural parameters were collected. These structural parameters included the outer diameter of the tire embryo skeleton. Diameter after inflation before vulcanization 1. Expansion rate before vulcanization (a), expansion rate after vulcanization (b), degree of change in expansion rate before and after vulcanization (c), tire noise parameters after vulcanization; tire noise parameters include the average noise energy or effective sound pressure RMS during the test period, and the highest instantaneous sound pressure level MAX recorded during the test period. The outer diameter of the tire body is formed by sequentially applying the airtight layer and the tire carcass to the bonding drum of the tire forming machine. a=( - )÷ ×100%; b=( - )÷ ×100%; c = (ab) ÷ b; Select embryos with RMS less than a set threshold A and MAX less than a set threshold B as low-noise samples, and set qualified intervals a, b, and c based on the low-noise samples respectively. Based on design requirements The acceptable range; S2. Before embryo vulcanization, select Tire blanks that meet the corresponding qualified range are used as pre-cured tire blanks, based on the pre-cured tire blanks... Calculate a, b, and c, and select the tire blanks that meet the corresponding qualified ranges for vulcanization; tire blanks that do not meet the corresponding qualified ranges are returned to the molding process for reshaping or are regarded as scrap tire blanks.

[0028] This method requires no additional noise reduction components. It directly controls the expansion degree of the tire in different production processes from the core process of tire molding to vulcanization. It fundamentally reduces problems such as uneven circumferential mass distribution and excessive differences in structural density caused by uneven expansion of different parts of the tire during vulcanization. This effectively suppresses the generation of the tire's inherent vibration frequency, avoids resonance with the vehicle body structure, and ultimately significantly reduces the low-frequency vibration and noise induced and transmitted by the tire's structural inhomogeneity during driving.

[0029] This method relies entirely on existing structural parameter control processes within the conventional tire production workflow to achieve noise control. It eliminates the need for consumers to bear additional usage and maintenance costs, fundamentally preventing the possibility of additional noise-reducing components detaching and becoming damaged. This significantly improves the reliability and durability of low-noise tires during use. Furthermore, it eliminates the need for manufacturers to invest in special production equipment or purchase exclusive noise-reducing materials, making it fully compatible with existing mature tire production lines without negatively impacting production efficiency. The pre-production parameter screening process directly eliminates substandard tire blanks that generate high and low frequency noise, achieving noise control for passenger vehicles from the design stage. Precise control of low-frequency tire noise completely avoids the various pain points of traditional noise reduction solutions. At the same time, it can stably control the noise in the 50~300Hz frequency band at a low level, with reliable and long-lasting noise reduction effect. It is especially suitable for electric vehicles where there is no internal combustion engine to cover tire noise, so that the tire noise level can be stably maintained in a low range during vehicle driving, greatly improving the quiet riding experience of passengers. The whole method has a clear logic and can be implemented. The parameter verification process is clear and will not introduce additional blind spots in quality control. It can be directly replicated and applied to the production control process of various passenger car tires to achieve large-scale production output of low-noise tires.

[0030] In some embodiments, the acceptable range for a is 2.0% to 4.5%; the acceptable range for b is 2.0% to 4.5%; and the acceptable range for c is -0.2 to 0.2.

[0031] By clearly defining the qualified ranges for a, b, and c, the potential subjective bias in setting the parameter ranges for low-noise samples is eliminated. This provides the entire screening and control process with a unified and directly executable hard standard. Relevant production operators do not need to make vague judgments based on experience; they can quickly complete the parameter verification of the tire blanks to be vulcanized simply by comparing the numerical ranges. This significantly reduces the learning cost and the probability of operational errors for personnel in the control process.

[0032] The pre-vulcanization expansion rate α is stably maintained within the range of 2.0% to 4.5%. This ensures that the deformation of the tire carcass after inflation is within a very reasonable range, guaranteeing a uniform tension distribution in the tire body and all supporting components. This avoids problems such as excessive stretching or relaxation of materials in localized areas, laying a solid foundation for subsequent low-noise performance from the tire carcass forming stage. Preferably, the pre-vulcanization expansion rate α is stably maintained within the range of 2.5% to 3.8%.

[0033] By controlling the post-vulcanization expansion rate (b) within the range of 2.0% to 4.5%, the tire blank can achieve optimal skeleton tension and material distribution uniformity after vulcanization within the vulcanization cavity of the tire vulcanization mold. This prevents stress concentration within the tire due to excessive or insufficient expansion during vulcanization, avoiding uneven stress distribution that leads to uneven periodic deformation during tire operation and fundamentally reducing low-frequency noise caused by abnormal vibrations. Preferably, the post-vulcanization expansion rate (b) is stably maintained between 2.5% and 3.3%.

[0034] By limiting the change in expansion rate c before and after vulcanization to the range of -0.2 to 0.2, it is further ensured that the tire expansion process from the pre-vulcanization inflation state to the vulcanization completion state is in a smooth and controllable state throughout, and there will be no situation where the difference in expansion rate between the two stages is too large. This completely avoids the problem of local misalignment and tension imbalance of the tire's internal structure caused by abrupt deformation before and after vulcanization.

[0035] The reasonable ranges of these three parameters work together to ensure a highly uniform overall rigidity distribution in the final tire, a regular and stable contact patch when the tire contacts the ground, and extremely low vibration levels during driving. This allows for stable and excellent low-frequency noise suppression without relying on any additional noise reduction components. It also simultaneously improves tire durability, reduces abnormal tire wear caused by uneven stress distribution, and maintains low-noise performance for extended periods without rapid degradation over time. The entire parameter standard is compatible with most standard passenger car tire production scenarios and can be directly embedded into existing production parameter verification processes. It can be implemented without significant adjustments to existing production procedures, helping manufacturers quickly achieve stable mass production of low-noise tires.

[0036] In some of these embodiments, in S1 and S2, The derivation yields:

[0037] Where e is a preset constant obtained through experiments; f is the thickness of the tread reinforcement structure applied to the tire body, obtained through actual measurement or design drawings; the tread reinforcement structure includes belt layer 1, crown belt layer 3 and tread 4.

[0038] If obtained through manual measurement This requires operators to complete the measurement within the confined space of the molding machine. This not only makes the measurement difficult and time-consuming, but also easily introduces additional numerical deviations due to deviations in the placement of measuring tools or reading errors by the measuring personnel. This, in turn, affects the accuracy of subsequent calculations of the three parameters a, b, and c, ultimately leading to fluctuations in the tire noise control effect.

[0039] and To derive this, one needs to obtain easily and accurately measured values. By taking measurements and combining them with a preset constant e and the tread reinforcement structure thickness f, which can be obtained directly from drawings or through precise field measurements, the accuracy can be quickly calculated to fully meet the control requirements. Numerical values ​​completely eliminate the need for direct measurement. This significantly improves the efficiency of parameter acquisition on the production site, eliminating cumbersome operations and also eliminating the need for direct measurement. Various measurement errors that may be introduced during the process further ensure the accuracy of core structural parameters. This ensures that the calculated values ​​of pre-curing expansion rate (a), post-curing expansion rate (b), and the degree of change in expansion rate (c) before and after curing perfectly match the actual structural state of the tire blank. This avoids the problem of qualified tire blanks being misjudged and rejected due to parameter distortion, or unqualified tire blanks flowing into subsequent curing processes. It can reduce unnecessary tire blank scrap rates, improve raw material utilization, reduce overall production costs, and further ensure the stability of the low-frequency noise suppression performance of the final tire. The entire derivation logic is simple and clear, and the calculation process does not require complex equipment support. It can be completed quickly using only a conventional workstation calculator. It is fully adapted to the fast-paced management needs of tire production sites and can be seamlessly integrated into the original production process without any negative impact on the production cycle. It provides a more convenient and reliable parameter acquisition path for large-scale low-noise tire production.

[0040] In some embodiments, the value of e ranges from 0.985 to 0.995.

[0041] When the value of e stably falls within the range of 0.985 to 0.995, based on Obtained through formula derivation The deviation of the actual outer diameter after the airtight layer and the tire body are applied on the bonding drum can be controlled within a very small range, which fully meets the accuracy requirements of the subsequent calculation of the three core parameters a, b, and c. The subsequent expansion rate calculation results will not be distorted due to the deviation of the preset constant value. This numerical range is derived from repeated calibration based on a large amount of measured data from passenger car tires of different specifications. It is compatible with the carcass material characteristics and molding process characteristics of most conventional passenger car radial tires. Manufacturers only need to select the corresponding fixed e-value within this range according to their own carcass rubber compound formulation and molding machine operating parameters, and can directly put it into mass production. There is no need to conduct a large number of calibration experiments for each new tire, which greatly reduces the workload of parameter calibration in the introduction of new products. At the same time, it can ensure that all tires of different specifications maintain a uniform high-precision standard in the parameter control process, fundamentally avoiding the parameter control failure problem caused by unreasonable constant settings. This further expands the applicability of the entire low-frequency noise control structure design method, making it compatible with the production needs of various passenger car tires of different brands and specifications, and always maintaining a stable low-frequency noise suppression effect. There will be no problem of control performance degradation due to tire specification switching, providing a unified and reliable parameter support for the mass production of low-noise tires for different product lines.

[0042] In some embodiments, the belt layer is composed of steel wire cord and rubber calendering composite, the included angle between the cord and the tire radial direction is 21°~33°, the diameter of the belt layer cord is 0.4mm~0.8mm, and the thickness of a single belt layer is 0.8mm~1.4mm; the tread reinforcement structure has two belt layers, and the cords of the two belt layers are inclined in opposite directions; The crown layer comprises a film layer consisting of cords wound around the tire circumference, a coating layer enclosing the film layer, and a rubber layer enclosing the coating layer; the cords of the crown layer are uniformly wound around the surface of the outermost belt layer, and the tension of the crown layer cords is controlled at 10N~50N during the winding process; the diameter of the crown layer cords is 0.5mm~0.9mm, and the thickness of the crown layer is 0.7mm~1.3mm; the crown layer cord material includes aramid material, nylon material, or a composite reinforcing material made of aramid blended with other high-performance fibers.

[0043] This complete set of parameter constraints allows the rigidity distribution of the tread reinforcement structure to reach a near-ideal uniform state. The two steel belt layers with opposite tilt directions can cancel each other out the shear forces from different directions during driving, keeping the circumferential and radial support rigidity of the tread highly consistent. This avoids local rigidity abrupt changes during tire contact with the ground, significantly reducing the impact vibration generated when the tread contacts and separates from the ground during tire rolling. The crown belt layer, with precise tension control, can further constrain the circumferential deformation of the belt layer, keeping the tension distribution of the belt layer uniform throughout the entire process, and preventing excessive local deformation during high-speed rolling. By setting these structural parameters, the tread reinforcement structure can quickly dissipate high-frequency vibrations generated during tire operation, while avoiding low-frequency resonance problems caused by uneven rigidity distribution. Without increasing the weight of the structure or changing the core processes of the original production, it further optimizes the dynamic mechanical properties of the tire, significantly weakening the conditions for low-frequency noise generation from the root of vibration. This makes the contact patch on the tire more regular and significantly improves the uniformity of deformation during rolling. It can not only stably reduce the level of low-frequency noise generated by the tire, but also simultaneously improve the tire's handling stability and wear resistance, further enhancing the noise reduction effect of the entire low-frequency noise control structure design method.

[0044] Furthermore, the tension of the crown layer cord is controlled at 25N~50N during the winding process.

[0045] In some embodiments, S1 further includes transferring multiple low-noise samples... and The design pattern depth obtained from the design drawings is then substituted into the following formula to calculate the low-noise samples. : = 2ASD+ ; ASD represents the design pattern depth, which is obtained from the design drawings; S2 also includes the embryo to be vulcanized. ASD and The following relationship must be satisfied: = 2ASD+ ; in, Represents multiple The mean.

[0046] The above solution integrates three previously independent core parameters: the diameter of the tire blank before inflation, the maximum diameter of the vulcanization cavity of the tire vulcanization mold, and the designed tread depth. It establishes a direct quantitative correlation between these three parameters. By statistically averaging data from a large number of sample tire blanks that have been verified to have excellent low-noise performance, a solution suitable for its own product system is obtained. Numerical analysis avoids the deviations caused by relying on empirical formulas to set parameters in traditional design processes. It enables the most precise matching between the core structural dimensions of the tire blank and the inner cavity dimensions of the vulcanizing mold. This ensures that after the tire blank is shaped inside the vulcanizing mold, the tire's body contour and tread root support rigidity fall precisely within the optimal range for low-noise performance, completely avoiding unnecessary deformation stress concentration in the tire's internal contour due to dimensional mismatch. This solution relies entirely on existing measured data and design drawings for statistical calculations, requiring no additional testing costs. It further narrows the allowable deviation range of parameters for the tire blank, ensuring that the core structural dimensions of all mass-produced tires approach the validated optimal low-noise sample state. This further reduces the noise performance dispersion between different products, ensuring that the low-frequency noise level of each tire produced remains stably within a low range, preventing excessive differences in noise levels within the same batch. This significantly improves batch consistency of low-noise tires, making it particularly suitable for large-scale mass production scenarios. It helps manufacturers achieve large-scale, stable production of low-noise tires, avoiding substandard noise performance in some products due to individual parameter deviations.

[0047] In some of these embodiments, The value range is -8mm to 8mm.

[0048] This numerical range, obtained through statistical verification using a large amount of low-noise sample data, is compatible with the size specifications of almost all conventional passenger car tires. It ensures that the matching relationship between the diameter of the tire blank before vulcanization and after inflation, and the maximum diameter of the vulcanization cavity and the designed tread depth of the tire vulcanization mold, remains optimal, preventing excessive dimensional deviations. When the value falls within the range of -8mm to 8mm, after the tire blank enters the vulcanizing mold, it will not be too small, which would cause the tire material to be unable to fully stretch and shape during the vulcanization process, resulting in insufficient internal tension and uneven rigidity distribution. Nor will it be too large, which would cause the tire blank to be excessively squeezed inside the mold, resulting in local material stacking and stress concentration. This ensures that the internal contour of the tire and the support structure at the root of the tread are all in a state of optimal low-noise performance after vulcanization. The deformation amplitude during tire rolling is always controlled within a reasonable range, reducing the generation of low-frequency vibrations from the root.

[0049] This numerical range eliminates the need for companies to conduct extensive verification experiments for every new tire specification. They only need to make minor adjustments within this range, based on their existing low-noise sample data, to obtain a range suitable for different products. The numerical values ​​significantly reduce the workload of parameter calibration during the new product development phase, while ensuring that the structural matching logic of all products remains within a verified and reliable range.

[0050] In some embodiments, S1 further includes measuring the tread thickness of the sample tire blank during assembly, and substituting the tread thickness and designed tread depth of multiple low-noise samples into the following formula to calculate the tread thickness of multiple low-noise samples. : h=ASD

[0051] Where h is the measured tread thickness and ASD is the designed tread depth, obtained from the drawings; S2 also includes that h and ASD of the tire carcass to be vulcanized must satisfy the following formula: h=ASD

[0052] in, Represents multiple The mean.

[0053] Traditional tire production control often focuses only on whether the tread thickness meets the drawing tolerance requirements, without establishing a direct correlation between tread thickness parameter fluctuations and the final tire's low-frequency noise performance. This method, however, by statistically analyzing the correspondence between tread thickness and design tread depth of a large number of low-noise samples, incorporates tread thickness parameters that directly affect tread rigidity distribution into the low-noise performance control system, and proposes... This unified control standard ensures that the tread thickness of all tire blanks to be vulcanized falls exactly within the verified optimal range. It prevents excessive tread thickness from causing excessive tread rigidity and excessive ground impact during rolling, which would lead to unnecessary vibration and noise. Conversely, it prevents insufficient tread rigidity from causing excessive compression deformation during rolling, which would lead to periodic low-frequency vibration. This ensures that the dynamic deformation characteristics of the tread are at the lowest level of low-frequency noise generation.

[0054] The tread thickness h can be measured directly at the tire blank forming station without the need for additional complex testing equipment. This improves the control accuracy of tread thickness from the traditional standard tolerance level to a high-precision level that adapts to low-noise performance. It further fills the blind spot in the control of the last core structural parameter in the tire forming stage, allowing the parameter control of the entire low-frequency noise control structural design method to cover all core structures from the tire blank skeleton to the tread, further enhancing the low-noise performance stability of the final finished tire.

[0055] In some of these embodiments, The value range is -1mm to 3mm.

[0056] This numerical range, obtained through statistical calibration of a large number of low-noise tire blank samples, can fully adapt to the tread structure design requirements of various passenger car tires, ensuring that the matching relationship between tread thickness and designed tread depth is always optimal. When the value of is stably within the range of -1mm to 3mm, the distribution ratio of the rubber material in the tread is just right so that the overall rigidity of the tread is in the most reasonable range. This ensures that the tread has sufficient support strength to avoid excessive redundant deformation during rolling, which would cause low-frequency vibration. It also ensures that the tread has appropriate cushioning and vibration absorption capacity, which can offset some of the impact energy transmitted from the road surface at the moment the tire contacts the ground, greatly reducing the magnitude of vibration transmitted to the inside of the tire, and further reducing the generation and outward radiation efficiency of low-frequency noise from the vibration transmission path.

[0057] This numerical range eliminates the need for companies to conduct extensive and lengthy verification tests on tires with different tread patterns and compounds. They only need to perform minor calibrations within this defined range, using their existing low-noise sample data, to quickly obtain a range suitable for different products. The numerical values ​​significantly reduce the workload of implementing this low-noise design method for tires with different tread patterns and compounds, while also avoiding [the negative impact of noise]. The abnormal tread rigidity caused by values ​​exceeding the reasonable range leads to negative issues such as increased low-frequency noise, abnormal tire wear, and increased rolling resistance. This method further ensures that passenger car tires of different design types can achieve stable and excellent low-frequency noise suppression effects. It also expands the applicable scenarios of the entire low-frequency noise control structure design method, fully covering passenger car tire products with different positioning needs, and achieving effective control of low-frequency noise without affecting other core tire performance.

[0058] In some embodiments, during the tire embryo forming process, the airtight layer 5, tire body 6, belt layer 1, crown belt layer 3 and tread 4 are first assembled in the radial direction of the tire in an uninflated state, and then the airtight layer 5, tire body 6, tire bead and tire sidewall 8 are assembled in an inflated state.

[0059] First, the airtight layer 5, carcass 6, belt layer 1, crown belt layer 3, and tread 4 of the core crown area of ​​the tire are assembled in an uninflated state. This ensures that all components of the crown are precisely fitted to the surface of the bonding drum without any stretching interference. The alignment accuracy between the components is higher, and the deformation tension caused by pre-inflation will not cause the components of the crown to shift or stretch unevenly. The rigidity distribution of the tire crown is guaranteed to be highly uniform from the assembly stage, and the subsequent low-frequency vibration problem caused by local stress concentration in the crown is avoided from the root.

[0060] The assembly of the sidewall 8 airtight layer 5, tire body 6, tire bead and sidewall 8 is completed under the inflated state, which can ensure that the tension distribution of each component in the sidewall 8 is uniform and consistent, and the dynamic deformation characteristics of the sidewall 8 remain stable throughout the process, without the problem of excessive rigidity differences in different areas of the sidewall 8.

[0061] This step-by-step assembly method allows for precise and controllable tension distribution across all components of the tire blank, from the crown to the sidewall, completely avoiding the problems of component misalignment and uneven tension that easily occur in traditional molding processes. This elevates the overall rigidity uniformity of the tire after vulcanization to a new level, ensuring highly synchronized deformation across all areas of the tire during rolling and preventing additional abnormal low-frequency vibrations. This further enhances the noise reduction effect of the entire low-frequency noise control structure design method. Through the description of multiple embodiments of the structural design method for solving low-frequency noise in passenger car tires according to the present invention, it can be seen that the embodiments of the structural design method for solving low-frequency noise in passenger car tires according to the present invention have at least one or more of the following advantages: 1. This method requires no additional noise reduction components. It directly controls the expansion degree of the tire in different production processes from the core process of tire molding to vulcanization. It fundamentally reduces problems such as uneven circumferential mass distribution and excessive differences in structural density caused by uneven expansion of different parts of the tire during vulcanization. This effectively suppresses the generation of the tire's inherent vibration frequency and avoids resonance with the vehicle body structure. Ultimately, it significantly reduces the low-frequency vibration and noise induced and transmitted by the tire's structural inhomogeneity during driving. Consumers do not need to bear additional usage and maintenance costs. It eliminates the possibility of additional noise reduction components falling off and being damaged at the source, and greatly improves the reliability and durability of low-noise tires during use.

[0062] 2. This method relies entirely on the existing structural parameter control process in the conventional tire production process to achieve noise control. It does not require manufacturers to invest in additional special production equipment or purchase exclusive noise reduction materials. It is fully compatible with existing mature tire production lines and will not negatively affect the original production efficiency. The entire method has a clear logic and is easy to implement. The parameter verification process is well-defined and will not introduce additional quality control blind spots. It can be directly replicated and applied to the production control process of various passenger car tires to achieve large-scale low-noise tire production output.

[0063] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0064] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A structural design method for solving low-frequency noise in passenger car tires, characterized in that, The steps include: S1. Determine the maximum diameter of the vulcanizing cavity of the tire vulcanizing mold through actual measurement or the instruction manual of the tire vulcanizing mold. ; Multiple pre-vulcanized tire embryos were selected as sample pre-vulcanized tire embryos, and their structural parameters were collected. These structural parameters included the outer diameter of the tire embryo skeleton. Diameter after inflation before vulcanization 1. Expansion rate before vulcanization (a), expansion rate after vulcanization (b), degree of change in expansion rate before and after vulcanization (c), tire noise parameters after vulcanization; tire noise parameters include the average noise energy or effective sound pressure RMS during the test period, and the highest instantaneous sound pressure level MAX recorded during the test period. The outer diameter of the tire body is formed by sequentially applying the airtight layer and the tire carcass to the bonding drum of the tire forming machine. a=( - )÷ ×100%； b=( - )÷ ×100%； c = (ab) ÷ b; Select embryos with RMS less than a set threshold A and MAX less than a set threshold B as low-noise samples, and set qualified intervals a, b, and c based on the low-noise samples respectively. Based on design requirements The acceptable range; S2. Before embryo vulcanization, select Tire blanks that meet the corresponding qualified range are used as pre-cured tire blanks, based on the pre-cured tire blanks... Calculate a, b, and c, and select the tire blanks that meet the corresponding qualified ranges for vulcanization; tire blanks that do not meet the corresponding qualified ranges are returned to the molding process for reshaping or are regarded as scrap tire blanks.

2. The structural design method for solving low-frequency noise in passenger car tires according to claim 1, characterized in that, The acceptable range for a is 2.0% to 4.5%; the acceptable range for b is 2.0% to 4.5%; and the acceptable range for c is -0.2% to 0.2%.

3. A structural design method for solving low-frequency noise in passenger car tires according to claim 1 or 2, characterized in that, In S1 and S2, The derivation yields: Where e is a preset constant obtained through experiments; f is the thickness of the tread reinforcement structure applied to the tire carcass, obtained through actual measurement or design drawings; the tread reinforcement structure includes the belt layer, the crown layer and the tread.

4. The structural design method for solving low-frequency noise in passenger car tires according to claim 3, characterized in that, The value of e ranges from 0.985 to 0.

995.

5. The structural design method for solving low-frequency noise in passenger car tires according to claim 3, characterized in that, The belt layer is made of steel cord and rubber calendering composite. The angle between the cord and the tire radial direction is 21°~33°. The diameter of the belt layer cord is 0.4mm~0.8mm and the thickness of a single belt layer is 0.8mm~1.4mm. The tread reinforcement structure has two belt layers with the cords of the two belt layers inclined in opposite directions. The crown layer comprises a film layer consisting of cords wound around the tire circumference, a coating layer enclosing the film layer, and a rubber layer enclosing the coating layer; the cords of the crown layer are uniformly wound around the surface of the outermost belt layer, and the tension of the crown layer cords is controlled at 10N~50N during the winding process; the diameter of the crown layer cords is 0.5mm~0.9mm, and the thickness of the crown layer is 0.7mm~1.3mm; the crown layer cord material includes aramid material, nylon material, or a composite reinforcing material made of aramid blended with other high-performance fibers.

6. A structural design method for solving low-frequency noise in passenger car tires according to claim 1 or 2, characterized in that, S1 also includes the processing of multiple low-noise samples. and The design pattern depth obtained from the design drawings is then substituted into the following formula to calculate the low-noise samples. : = 2ASD+ ; ASD represents the design pattern depth, which is obtained from the design drawings; S2 also includes the embryo to be vulcanized. ASD and The following relationship must be satisfied: = 2ASD+ ; in, Represents multiple The mean.

7. A structural design method for solving low-frequency noise in passenger car tires according to claim 6, characterized in that, The value range is -8mm to 8mm.

8. A structural design method for solving low-frequency noise in passenger car tires according to claim 6, characterized in that, S1 also includes measuring the tread thickness during sample tire assembly, and substituting the tread thickness and designed tread depth of multiple low-noise samples into the following formula to calculate the tread thickness of multiple low-noise samples. : h=ASD Where h is the measured tread thickness and ASD is the designed tread depth, obtained from the drawings; S2 also includes that h and ASD of the tire carcass to be vulcanized must satisfy the following formula: h=ASD in, Represents multiple The mean.

9. A structural design method for solving low-frequency noise in passenger car tires according to claim 8, characterized in that, The value range is -1mm to 3mm.

10. A structural design method for solving low-frequency noise in passenger car tires according to claim 1 or 2, characterized in that, During the tire embryo formation process, the airtight layer, tire body, belt layer, crown belt layer and tread are first assembled radially in the tire under an uninflated state, and then the sidewall airtight layer, tire body, bead and sidewall are assembled under an inflated state.

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