Tread assembly outside belt ply of tire, mold, and manufacturing method

Abstract

A tread assembly (101) outside a belt ply of a tire, comprising a vulcanized rubber body (102), and an array of a plurality of hollow cavities (103) distributed on the vulcanized rubber body (102), wherein each cavity (103) comprises a neck portion (103b) recessed inwards on the outer side surface of the vulcanized rubber body (102), and a base portion (103a) that is located on the inner side of the neck portion (103b) and is integrally connected to the neck portion (103b); the first ratio of the maximum cross-sectional area of the base portion (103a) to the cross-sectional area of the neck portion (103b) is 5:1. Further disclosed are a tire, a mold for manufacturing a tread assembly outside a belt ply of a tire, and a manufacturing method for a tread assembly outside a belt ply of a tire. The structure of the tread assembly is provided with a Helmholtz resonant cavity that is elongated enough in neck portion and large enough in base portion size and is used as a silencing cavity, thereby achieving a good silencing effect on the radiation noise of the tire within the main frequency range.

Description

A tread assembly outside the belt layer of a tire, a mold and a manufacturing method Technical Field

[0001] The present application relates to a tread component outside a belt layer of a tire, a mold and a manufacturing method. Background Art

[0002] Tire noise seriously affects driving comfort and causes serious noise pollution to the surrounding environment. Relevant regulations have put forward requirements for the control of tire coasting noise, and the tire noise level index values ​​are getting lower and lower.

[0003] Tire noise is generally categorized as low-frequency structure-borne noise, cavity noise, tread knocking noise, and pumping noise. Low-frequency structure-borne noise, with a frequency range below 300Hz, can be transmitted into the vehicle through the chassis. Tread knocking noise and pumping noise, however, are generated by the high-speed rotation of the tires and propagate through air radiation into the vehicle interior and the surrounding environment. For example, the noise spectrum generated by the tread impact of a radial tire on a passenger car has most of its energy concentrated in the 800Hz-2000Hz range.

[0004] While many tire noise reduction methods have been implemented, there's still no effective solution for tire radiated noise. First, the improvements achievable through optimizing rubber formulations and tread pattern design have reached their limits. Furthermore, for tires with specialized requirements, such as snow tires, tread pattern modifications are limited. Furthermore, while applying sound-absorbing cotton to the inside of the tire can effectively suppress cavity noise, this primarily affects the noise transmitted into the vehicle, which has a frequency of only around 220Hz and has no effect on radiated noise from the tire.

[0005] Summary of the Invention

[0006] The present application is provided to address problems in the prior art. The application aims to provide a tire tread assembly, mold, and manufacturing method outside the belt layer of a tire. The resulting tread assembly structure is provided with a Helmholtz resonance cavity with a sufficiently slender neck and a sufficiently large base volume as a soundproofing chamber, which can achieve good soundproofing effects in the main frequency range of tire radiated noise.

[0007] According to a first embodiment of the present application, a tread assembly outside the belt layer of a tire is provided. The tread assembly includes a vulcanized rubber body and an array of multiple hollow cavities distributed within the vulcanized rubber body. Each cavity includes a neck portion recessed inwardly from the outer surface of the vulcanized rubber body and a base portion integrally connected to the neck portion on the inner side thereof. A first ratio of the maximum cross-sectional area of ​​the base portion to the cross-sectional area of ​​the neck portion is greater than 5:1.

[0008] According to a second embodiment of the present application, a tire is provided, characterized by comprising a belt layer and a tread assembly according to various embodiments of the present application outside the belt layer. The tread assembly comprises a vulcanized rubber body and an array of multiple hollow cavities distributed within the vulcanized rubber body. Each cavity comprises a neck portion recessed inwardly from the outer surface of the vulcanized rubber body and a base portion integrally connected to the neck portion on the inner side thereof, wherein a first ratio of the maximum cross-sectional area of ​​the base portion to the cross-sectional area of ​​the neck portion is greater than 5:1.

[0009] According to a third embodiment of the present application, a mold for manufacturing a tread component outside the belt layer of a tire is provided. The mold includes a first mold portion, a second mold portion, and a third mold portion. The first mold portion includes an array of first protrusions arranged circumferentially, which are used to vulcanize and mold the base of the hollow cavity in the tread component. The second mold portion is arranged radially outward from the first mold portion and includes an array of second protrusions arranged circumferentially, which are used to vulcanize and mold the neck of the hollow cavity in the tread component, and the neck is integrally connected to the corresponding inner base, thereby vulcanizing and molding an array of multiple hollow cavities distributed on the vulcanized rubber body. The third mold portion is configured to carry the array of the first protrusions and the array of the second protrusions on the radial inner side, wherein a first ratio of the maximum cross-sectional area of ​​the first protrusion to the cross-sectional area of ​​the second protrusion is greater than 5:1.

[0010] According to a fourth aspect of the present application, a mold for manufacturing a tread component outside a tire belt is provided. In addition to the third aspect, the third mold portion is configured to sequentially support the array of the second protrusions and the array of the first protrusions radially inward, wherein the first protrusions are physically or chemically decomposable so as to be removed after vulcanization molding of the tread component without tearing the neck.

[0011] According to the fifth embodiment of the present application, a mold for manufacturing a tread component outside the belt layer of a tire is provided. Based on the third embodiment, the third mold part includes a separate first mold sub-part and a second mold sub-part. The first mold sub-part carries the array of the first protrusions on the radial inner side for vulcanization molding the base of the hollow cavity in the tread component. The mold also includes a plurality of fourth mold parts, each of which is adapted to each base of the cavity so that each base can be filled in after the base is vulcanized. The second mold sub-part carries the array of the second protrusions on the radial inner side so that a neck can be vulcanized and molded with the fourth mold part filled in the base, and connected to the corresponding inner base as a whole. The fourth mold part is physically or chemically decomposable so that it can be removed after the vulcanization molding of the tread component is completed without tearing the neck.

[0012] According to a sixth embodiment of the present application, a mold for manufacturing a tread assembly outside the belt layer of a tire is provided. Based on the third embodiment, the third mold portion includes a separate first mold sub-section and a second mold sub-section. The first mold sub-section carries an array of the first protrusions on the radially inner side for vulcanization molding the base of the hollow cavity in the tread assembly and the corresponding first tread portion. The second mold sub-section carries an array of the second protrusions on the radially inner side for vulcanization molding the neck of the cavity and the corresponding second tread portion. The second tread portion is constructed to be tightly fitted and adhered to the outer periphery of the first tread portion.

[0013] According to the seventh embodiment of the present application, a method for manufacturing a tread component outside the belt layer of a tire is provided. The manufacturing method includes performing the following steps using the mold according to the fourth embodiment of the present application. The mold is used to perform vulcanization molding to integrally form a vulcanized rubber body having an array of multiple hollow cavities, with the second protrusion remaining in the neck of the cavity and the first protrusion remaining in the base. The third mold portion is moved radially outward together with the second protrusion, thereby removing the second protrusion and leaving a hollow neck. The first protrusion is physically or chemically decomposed, so that the decomposed first protrusion is removed through the hollow neck without tearing the neck.

[0014] According to an eighth aspect of the present application, a method for manufacturing a tread component outside the belt layer of a tire is provided. The manufacturing method includes performing the following steps using the mold according to the fifth aspect of the present application. The first mold subsection, along with the array of first protrusions, is subjected to vulcanization molding to form a first tread portion having a base portion of the cavity, with the first protrusions remaining within the base portion. The first mold subsection, along with the array of first protrusions, is moved radially outward, thereby removing the first protrusions from the base portion, leaving a hollow base portion of the cavity. Each fourth mold section is inserted into each hollow base portion of the cavity. With the base portion filled with the fourth mold section, the second mold subsection, along with the array of second protrusions, is subjected to vulcanization molding radially outward of the first tread portion to form a second tread portion having a neck portion of the cavity, with the second protrusions remaining within the neck portion. The second mold subsection, along with the array of second protrusions, is moved radially outward, thereby removing the second protrusions from the neck portion, leaving a hollow neck portion of the cavity integrally connected to the corresponding inner base portion. The fourth mold part is physically or chemically decomposed so that the decomposed fourth mold part can be removed through the hollow neck without tearing the neck, thereby forming a vulcanized rubber body having an array of a plurality of hollow cavities distributed therein.

[0015] According to the ninth embodiment of the present application, a method for manufacturing a tread component outside the belt layer of a tire is provided. The manufacturing method includes performing the following steps using the mold according to the sixth embodiment of the present application. The first mold sub-section is used together with the array of the first protrusions carried thereon to perform vulcanization molding to form a first tread portion having a base of the cavity, and the first protrusion is removed from the base by moving the first mold sub-section together with the array of the first protrusions radially outward. The second mold sub-section is used together with the array of the second protrusions carried thereon to perform vulcanization molding to form a second tread portion having a neck of the cavity, and the second mold sub-section is used together with the array of the second protrusions radially outward to remove the second protrusion from the neck. The second tread portion having a hollow neck is tightly fitted and adhered to the outer periphery of the first tread portion having a hollow base, thereby forming a vulcanized rubber body having an array of multiple hollow cavities.

[0016] By utilizing the tread assembly, mold, and manufacturing method outside the belt layer of the tire according to various embodiments of the present application, an array of sound-absorbing chambers including a neck and a base are distributed on the obtained tread assembly, and each sound-absorbing chamber operates in the form of a Helmholtz resonance cavity. The first ratio of the maximum cross-sectional area of ​​the base to the cross-sectional area of ​​the neck can be greater than 5:1, or even greater, so that the neck is sufficiently slender and the base volume is sufficiently large, thereby achieving a good sound-absorbing effect for the main frequency range of the tire's radiated noise, such as but not limited to below 5kHz, or refined to 800Hz-2000Hz, or refined to 500Hz-2000Hz, or even reduced to within 500Hz. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar components. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the description and claims, serve to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

[0018] FIG1 is a schematic structural diagram of a tread assembly outside a belt layer of a tire according to an embodiment of the present application.

[0019] FIG2 is a schematic structural diagram of a cavity in a tread assembly according to an embodiment of the present application that operates in a Helmholtz resonance cavity mechanism.

[0020] FIG3 shows an energy distribution diagram of radiation noise of a car tire at various frequencies according to an embodiment of the present application.

[0021] FIG4 is a schematic diagram showing the sound absorption effect of the tread assembly on the radiated noise of the tire according to an embodiment of the present application.

[0022] FIG5 is a schematic diagram showing Example 1 of a mold for manufacturing a tread component outside a belt layer of a tire according to an embodiment of the present application.

[0023] FIG6 is a schematic diagram showing Example 2 of a mold for manufacturing a tread component outside a belt layer of a tire according to an embodiment of the present application.

[0024] FIG7 is a schematic diagram showing Example 3 of a mold for manufacturing a tread component outside a belt layer of a tire according to an embodiment of the present application.

[0025] FIG8 is a schematic diagram showing Example 4 of a mold for manufacturing a tread component outside a belt layer of a tire according to an embodiment of the present application.

[0026] FIG9 is a flowchart illustrating a method for manufacturing a tread component outside a belt layer of a tire using the mold of Example 2 according to an embodiment of the present application.

[0027] FIG10 is a schematic flow chart showing a method for manufacturing a tread component outside a belt layer of a tire using the mold of Example 3 according to an embodiment of the present application.

[0028] FIG11 is a schematic flow chart showing a method for manufacturing a tread component outside a belt layer of a tire using the mold of Example 4 according to an embodiment of the present application.

[0029] 12 is a schematic diagram showing a transverse interface of a connection between a neck portion and a base portion of a tread component outside a belt layer of a tire manufactured using a mold of Example 3 or 4 according to an embodiment of the present application.

[0030] 13 is a schematic diagram showing the effect of different vulcanization times of the first layer of rubber on the shear strength of the interface during the process of manufacturing a tread component using the mold of Example 3 according to an embodiment of the present application.

[0031] FIG14 is a schematic diagram showing the effect of increasing the roughness of the mold surface on the shear strength of the interface during the process of manufacturing a tread component using the mold of Example 3 according to an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific embodiments, but are not intended to limit the present application. For the various steps described herein, if there is no necessity for a contextual relationship between each other, the order in which they are described as examples herein should not be regarded as a limitation, and those skilled in the art should know that they can be adjusted in order as long as the logic between them is not destroyed, resulting in the inability to implement the entire process.

[0033] Generally speaking, a tire, from the inside out, includes a tire blank, one or more belt layers, and a tread assembly assembled on the outside of the belt layer. For example, the manufacturing process of a tire, such as a passenger car tire, is as follows. The two bead ring assemblies of the tire are placed at both ends of a building drum, an airtight layer is wound around the middle of the building drum, and then the carcass cord layer is wound on top of the airtight layer. The bead ring assembly is pushed in from both sides toward the middle, so that the carcass cord layer is rolled up to cover and wrap the bead ring assembly. Next, the sidewall rubber is bonded to both ends, and the bonded areas of the bead ring assembly, carcass cord layer, airtight layer, and sidewall rubber are compacted to form a tire blank (also known as a semi-finished tire blank). The belt layer can be laid out on the outside of the semi-finished tire blank, and the vulcanized rubber assembly can be laid out on the outside of the belt layer, thereby forming a tread assembly outside the belt layer. The manufacturing of the parts of the tire other than the belt layer and the tread assembly in this application can use conventional processes and will not be repeated here.

[0034] FIG1 is a schematic structural diagram of a tread assembly 101 outside a belt layer 100 of a tire according to an embodiment of the present application.

[0035] As shown in FIG1 , the tread assembly 101 includes a vulcanized rubber body 102 and an array of multiple hollow cavities 103 distributed on the vulcanized rubber body 102. Each cavity 103 includes a neck portion 103b recessed inwardly from the outer surface of the vulcanized rubber body 102 and a base portion 103a integrally connected to the inner side of the neck portion 103b. A first ratio of the maximum cross-sectional area of ​​the base portion 103a to the cross-sectional area of ​​the neck portion 103b is greater than 5:1.

[0036] Each cavity 103 can operate as a Helmholtz resonator mechanism and serve as a soundproofing chamber. As shown in Figure 2, S represents the cross-sectional area of ​​the neck 103b, l represents the length of the neck 103b, and V represents the volume of the base 103a. When a sound wave enters the Helmholtz resonator, resonance occurs within the cavity, causing the sound wave energy to dissipate within the resonant cavity. The frequency of the absorbed sound is determined by the size of the resonant cavity, as shown in formula (1):

[0037] Where f represents the frequency range that the cavity is intended to absorb, c represents the speed of sound, S represents the cross-sectional area of ​​the neck, l represents the length of the neck, and V represents the volume of the base. Formula (1) shows that by increasing the length l of neck 103b, decreasing the cross-sectional area S of neck 103b, and increasing the volume V of base 103a, the frequency range of sound absorbed can be reduced.

[0038] Formula (1) can be further transformed into formula (1'):

[0039] Among them, S j represents the cross-sectional area of ​​the neck, S f represents the cross-sectional area of ​​the base, and V represents the volume of the base. Assuming the length of the base is m, the volume V = S f m, the length of the neck plus the base H = m + l. However, the length l of the neck 103b and the cross-sectional area S of the neck 103b are j Due to the limitations of the manufacturing process, its effect on reducing the frequency is limited.

[0040] Referring to formula (1'), in S j / S f When the value of is constant, the value of f is minimum when l=H / 2, and the volume V of the base 103a can be relatively larger. Under this premise, it is verified through repeated experiments that when the first ratio S of the maximum cross-sectional area of ​​the base 103a to the cross-sectional area of ​​the neck 103b is j / S f When the ratio is set to approximately 5:1, for a typical passenger car tire (e.g., H = 10 mm), the frequency range of noise that the cavity can absorb can be basically controlled to below 5 kHz, thereby absorbing the majority of the tire's radiated noise as needed. Furthermore, when the first ratio of the maximum cross-sectional area of ​​the base portion 103a to the cross-sectional area of ​​the neck portion 103b is 5:1, when the tread assembly 101 is manufactured and processed according to the new process proposed in this application, the connection between the neck portion and the base portion, as well as the narrower neck portion, can be prevented from cracking or tearing. Furthermore, the base portion, the neck portion, and the connection between the two can all maintain relatively smooth surfaces, with less residue in the cavity and a smooth connection.

[0041] FIG3 shows the energy distribution diagram of the radiated noise of the car tire at various frequencies according to an embodiment of the present application. As shown in FIG3 , the radiated noise of the car tire has components of various frequencies, but the equivalent noise level (dB(A) / 20u Pa) is the highest in the frequency range of 800Hz-2000Hz. Specifically, a 3dB difference in energy at two frequencies represents a double difference in energy. It can be seen that the noise above 5000Hz is more than 21dB smaller than the noise at 1000Hz, which is equivalent to the sound energy above 5000Hz being only 7.8‰ of the sound energy at 1000Hz. Therefore, if the frequency range of the noise that the cavity can absorb is controlled below 5kHz, or even within the frequency range of 800Hz-2000Hz, the radiated noise of the car tire can be efficiently absorbed.

[0042] The frequency distribution of radiated noise from tires of other models is generally similar to that of Figure 3, but with slight deviations. In some embodiments, by using the cavity 103 as a soundproofing chamber and adjusting the cross-sectional area S of the neck 103b, the length l of the neck 103b, and the volume V of the base 103a, the frequency range of the noise absorbed by the cavity 103 can be adapted to the peak frequency of the radiated noise of the tire. For example, if the peak frequency is 900Hz, then the frequency range of the noise absorbed by the cavity 103 is adjusted to fall within a 3dB range, a 4dB range, a 5dB range, etc. on both sides of 900Hz, thereby achieving adaptation to the peak frequency. For example, for passenger car tires, absorbing sound within a certain frequency range above 800Hz can achieve a good silencing effect on radiated noise; for another example, for truck tires, absorbing sound within a certain frequency range above 500Hz can achieve a good silencing effect on radiated noise.

[0043] The inventors have developed a variety of new processes to manufacture the tread component 101 , in which the cavity 103 is formed so that a first ratio of the maximum cross-sectional area of ​​the base 103 a to the cross-sectional area of ​​the neck 103 b can be greater than 5:1.

[0044] Such a first ratio, if achieved using conventional direct demolding methods, could result in cracking, such as tearing, of the neck portion 103b or at the junction between the neck portion 103b and the base portion 103a, severely impacting sound absorption. In contrast, the inventors' various novel processes, described below, enable the manufacture of a cavity 103 in which the first ratio of the maximum cross-sectional area of ​​the base portion 103a to the cross-sectional area of ​​the neck portion 103b is greater than or equal to 10:1, or even greater than or equal to 23:1, or even greater. This further reduces the frequency range of sound absorption, adapting it to the lower frequency range of the intended tire radiated noise, such as, but not limited to, as low as 800Hz-2000Hz, or as low as 800Hz, or even as low as 500Hz. Furthermore, these novel processes can prevent cracking or tearing at the junction between the neck portion 103b and the base portion 103a, as well as at the neck portion 103b.

[0045] In some embodiments, the new process can also reduce the volume of residual rubber attached to the inner wall of the base 103a after vulcanization. Experiments have shown that the ratio of residual rubber to the volume of the base can be less than 4%. In other words, the new process can not only produce cavities 103 with a first ratio greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 23:1, or even greater than 56:1, but also ensure that the surface of the molded cavity 103 is less damaged, has less residue, and has smooth connections, further ensuring a good sound absorption coefficient and a precise sound absorption frequency range.

[0046] In some embodiments, the cross-sectional area S of the neck j The third ratio of the second ratio of the length l of the neck to the volume of the base is set according to the above formula (1), wherein the second ratio is The third ratio is

[0047] Taking the cavity 103 with a cylindrical neck 103b and a rectangular base 103a as an example, the inventors manufactured such a cavity 103, where the length l of the neck 103b is 6 mm and the cross-sectional area S of the neck 103b is 1.7671 mm 2 The volume V of the base 103a is 10*10*6=600mm 3 , then the second ratio of the cross-sectional area of ​​the neck to the length of the neck is 1.7671mm 2 / 6mm=0.2945mm, and the third ratio of the second ratio to the volume of the base is 0.2945mm / 600mm 3 =4.9e-4 / mm 2By setting the second ratio and the third ratio, the cavity 103 functions as a sound-absorbing chamber. For tire radiation noise with a peak frequency between approximately 900 Hz and 1000 Hz (e.g., 950 Hz), as shown in FIG. 4 , the sound absorption coefficient can be greater than or equal to 0.3, or even reach approximately 0.35.

[0048] In some embodiments, by properly setting the second ratio and the third ratio, or by properly setting the cross-sectional area S of the neck 103 b, the length l of the neck 103 b, and the volume V of the base 103 a, the sound absorption coefficient of the array of cavities 103 at the peak frequency of tire noise can be made greater than 0.4, or even greater than 0.5, greater than 0.6, greater than 0.7, and so on.

[0049] Specifically, the sound absorption frequency and absorption coefficient of a cavity depend on its dimensions. For target frequencies between 500 Hz and 3000 Hz, the absorption coefficient is consistently above 0.4, with the coefficient increasing as the frequency decreases. For example, a single cavity 103 has a neck 103b that is 4 mm long and a base 103a that is 4 mm high. The combined heights of the neck 103b and base 103a are 10 mm. For example, assuming the base 103a is a square, its side length is assumed to be a. When the dimensions of the neck 103b remain constant and the side length a of the base 103a varies, the absorption frequency and absorption coefficient are shown in Table 1.

[0050] Table 1

[0051] As can be seen from Table 1, when the side length a increases, the sound absorption frequency decreases, and the sound absorption coefficient increases, and the sound absorption coefficient ranges from 0.4 to 0.66.

[0052] On the other hand, the overall sound absorption effect of the cavity array also depends on the number of cavities (arrangement density). The sound absorption effect of multiple cavities combined is greater than that of a single cavity. If the sound absorption coefficient of a single cavity 103 is not less than 0.4, considering the combined effect of the array composed of multiple cavities 103, it is reasonable to have a sound absorption coefficient greater than or equal to 0.4.

[0053] In some embodiments, the angle between the neck 103b and the base 103a at the connection can have a preset angle range, and within the preset angle range, using a direct demolding method will cause the connection between the neck and the base and / or the neck to crack or tear. By way of example only, when the angle α is 160°, due to the relatively sharp rubber sheet between the neck 103b and the base 103a, it is very difficult to maintain the integrity of the connection between the neck 103b and the base 103a and / or the neck 103b using a direct demolding method. In contrast, the new process proposed by the inventors does not have this limitation. When α is any angle between 0° and 180°, an array of cavities 103 can be successfully manufactured. Furthermore, the molded cavities 103 can have less surface trauma, less residue, and smooth connections, further ensuring a good sound absorption coefficient and an accurate sound absorption frequency range.

[0054] The inventors have shown through rubber vulcanization experiments that the tire assembly 101 processed according to the new process in the embodiment of the present application has a transverse shear strength of 1.3Mpa-1.5Mpa in the cross section at the connection between the neck 103b and the base 103a, so that it can contact various types of surfaces in a rolling manner and withstand normal loads and transverse shear loads during the life of the tire without causing tearing at the connection between the neck 103b and the base 103a.

[0055] The length l of the neck portion 103b and the longitudinal depth of the base portion 103a together determine the longitudinal depth of the cavity 103. The longitudinal depth of the cavity 103 can be adjusted based on the thickness of the tire's tread assembly 101 and the absorption frequency range of the cavity 103. For example, the depth can be set to less than 80% of the thickness of the tread assembly 101 to ensure the strength of the tread assembly 101 while achieving the desired absorption frequency range. In other words, for a tread assembly 101 with a thickness of 10mm, the longitudinal depth of the cavity can reach 8mm. Furthermore, the inventors have experimentally verified that, in practice, only a 1mm thick rubber cover belt layer is required to ensure that the belt layer is not exposed within the cavity. Therefore, the longitudinal depth of the cavity 103 can reach the thickness of the tread assembly 101 minus 1mm. How the longitudinal depth of cavity 103, that is, the length l of neck portion 103b, and the longitudinal depth of base portion 103a (associated with its volume V) affect the absorption frequency range of cavity 103 can be understood in conjunction with formula (1) and will not be further elaborated here. Specifically, for a second absorption frequency range lower than the first absorption frequency range, the corresponding second longitudinal depth of cavity 103 is greater than the first depth corresponding to the first absorption frequency range.

[0056] Furthermore, the thickness of the tread assembly 101 is related to the specifications of the tire. The thicker the tread assembly 101 of the tire of the specification, the greater the longitudinal depth of the cavity 103 can be, thereby achieving a lower absorption frequency range.

[0057] In some embodiments, a visible lateral interface is formed at the connection between the neck portion 103b and the base portion 103a. This interface is caused by the separate or step-by-step molding of the neck portion 103b and the base portion 103a during the manufacturing process of the tread component 101. The inventors provide several examples of manufacturing processes below, detailing how the neck portion 103b and the base portion 103a are separately or step-by-step molded. In practice, if a lateral interface at the connection between the neck portion 103b and the base portion 103a is visible in a cross-section of the finished product of the tread component 101, it means that the neck portion 103b and the base portion 103a are separately or step-by-step molded, rather than being integrally molded.

[0058] Accordingly, the present application may provide a tire including a belt layer 100 and a tread assembly 101 outside the belt layer. Various embodiments of the tread assembly 101 in the present application may be combined here and will not be described in detail herein.

[0059] The manufacturing process of the tread assembly 101 (as shown in FIG. 9 to FIG. 11 ) is exemplarily described below in conjunction with the corresponding mold structure (as shown in FIG. 5 to FIG. 8 ).

[0060] Figure 5 shows a schematic diagram of Example 1 of a mold for manufacturing a tread assembly outside the belt layer of a tire according to an embodiment of the present application. As shown in Figure 5, as Example 1, the mold includes a first mold section 501, a second mold section 502, and a third mold section 503. Please note that the term "mold section" herein is intended to refer to a component of a mold assembly, which can refer to a single mold member or a portion of a mold member, such as, but not limited to, a protrusion or groove.

[0061] The first mold section 501 includes an array of circumferentially arranged first protrusions for vulcanization-molding the base of the hollow cavity in the tread assembly. The second mold section 502 is arranged radially outward from the first mold section 501 and includes an array of circumferentially arranged second protrusions for vulcanization-molding the neck of the hollow cavity in the tread assembly, with the neck being integrally connected to the corresponding inner base, thereby vulcanizing and molding a plurality of hollow cavities distributed on the vulcanized rubber body. The third mold section 503 is configured to support the array of the second protrusions and the array of the first protrusions radially inward. The first ratio of the maximum cross-sectional area of ​​the first protrusion to the cross-sectional area of ​​the second protrusion is greater than 5:1. Accordingly, the first ratio of the maximum cross-sectional area of ​​the formed base to the cross-sectional area of ​​the neck is also greater than 5:1.

[0062] In some embodiments, the third mold portion 503 is integrally formed with the array of the second protrusions, the array of the first protrusions is integrally formed with the array of the second protrusions, or is detachably connected and fixed to the array of the second protrusions.

[0063] By employing a separable design for the first protrusion with a significantly larger cross-sectional area and the second protrusion with a much smaller cross-sectional area radially outward, such as by making the first protrusion detachably fixed to the end of the corresponding second protrusion (as shown in FIG. 5 ), or by making the first protrusion itself employ a physically or chemically decomposable structure or material (as shown in FIG. 6 ), or by making the first protrusion and the second protrusion part separate mold components (as shown in FIG. 7 and FIG. 8 ), the first ratio can be freed from the process limitations of the direct demolding method. Specifically, using such a mold design, a cavity can be produced in which the first ratio of the maximum cross-sectional area of ​​the base to the cross-sectional area of ​​the neck is greater than or equal to 10:1, or even greater than or equal to 23:1, or even 56:1 or greater, thereby further reducing the frequency range of sound absorption to match the lower frequency range of the tire radiated noise to be absorbed, such as, but not limited to, as low as 800 Hz-2000 Hz, as low as 800 Hz, or even as low as 500 Hz. At the same time, the various new processes can also avoid cracking or tearing of the connection between the neck and the base and the neck.

[0064] In some embodiments, the new process can also reduce the volume of residual rubber attached to the inner wall of the base after vulcanization. Experiments have shown that the ratio of residual rubber to the volume of the base can be less than 4%. In other words, the new process can not only produce cavities with a first ratio greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 23:1, or even greater, but also achieve less trauma and residue on the molded cavity surface, and smooth connections, further ensuring a good sound absorption coefficient and a precise sound absorption frequency range.

[0065] FIG6 illustrates a schematic diagram of Example 2 of a mold for manufacturing a tread component outside the belt layer of a tire according to an embodiment of the present application. As shown in FIG6 , the third mold portion 503 is configured to sequentially support an array of the second raised portions (i.e., the second mold portion 502) and an array of the first raised portions (i.e., the first mold portion 501) radially inwardly. The first raised portions 501 are physically or chemically decomposable so that they can be removed without tearing the neck after the vulcanization molding of the tread component is completed. For example, the first raised portion 501 can be composed of a plurality of sub-portions with a thickness comparable to that of the second raised portion 502, which can be combined into a single piece for molding. Upon completion of molding and requiring demolding, the sub-portions can be separated and removed one by one through the neck without tearing the neck. For another example, the first raised portion 501 can be made of a material that chemically reacts with a solvent (which does not react with vulcanized rubber) to dissolve it. Upon completion of molding and requiring demolding, the first raised portion 501 can be treated with a solvent to dissolve it and be removed smoothly through the neck in a liquid state without tearing the neck.

[0066] FIG9 is a flowchart illustrating a method for manufacturing a tread component outside a belt layer of a tire using the mold of Example 2 according to an embodiment of the present application.

[0067] As shown in Figure 9, in step 901, with the first protrusion 501 assembled and fixed to the end of the corresponding second protrusion 502, the mold is used for vulcanization molding to form a vulcanized rubber body with an array of multiple hollow cavities distributed in an integrated manner. Before demolding, the second protrusion 502 remains in the neck of the cavity and the first protrusion 501 remains in the base. Next, the second protrusion 502 and the first protrusion 501 are demolded in steps rather than directly. Specifically, in step 902, the third mold part 503 is first moved radially outward together with the second protrusion 502, thereby removing the second protrusion 502 and leaving a hollow neck. The first protrusion 501 is detachably assembled and fixed to the end of the corresponding second protrusion 502. Therefore, at this time, the first protrusion 501 has not been pulled out and remains in the base. In step 903, the first protrusion 501 may be physically or chemically decomposed, for example, dissolved or decomposed into sub-parts with a thickness and size equivalent to the second protrusion 502, so that the decomposed first protrusion 501 can be removed through the hollow neck without tearing the neck.

[0068] Example 1 of the manufacturing process

[0069] Curing equipment: Use a standard curing equipment, such as a closed mold curing press.

[0070] Control parameters: During the vulcanization process, pressure, temperature, and humidity need to be strictly controlled. For example, the pressure may need to be maintained at 10-15 bar, the temperature at 150-160 degrees Celsius, and the humidity at 50-60% RH.

[0071] Rubber composition: Tire rubber is mainly composed of natural rubber, synthetic rubber (such as styrene-butadiene rubber, nitrile rubber, chloroprene rubber, etc.), fillers (such as carbon black, silica treated with silane coupling agent), softeners, protective agents, sulfur, etc.

[0072] Vulcanization molding time: The vulcanization molding time of each step depends on the specific tire model and specifications. Generally speaking, the vulcanization process may take 10-20 minutes.

[0073] In the example of a car tire:

[0074] 1. Unvulcanized tire specifications: Choose a tire with a sidewall thickness of 15-20mm and a crown thickness of 8-10mm.

[0075] 2. Curing bladder specifications: Use common butyl bladders.

[0076] 3. Vulcanization process: A contracted tire vulcanization bladder is inserted into the inner side of an unvulcanized tire blank disposed in a tire vulcanization mold. Then, with the tire vulcanization mold closed, a heating medium (e.g., steam) and a pressurizing medium (e.g., nitrogen) are injected into the bladder to expand the bladder. The bladder is pressurized to 15 bar and maintained for 15 minutes. The bladder is then heated to 160°C and maintained for 20 minutes while the humidity is controlled at 50% RH to vulcanize the unvulcanized tire.

[0077] 4. Opening the vulcanization mold: The control system instructs the third mold portion 503 of the vulcanization mold, together with the second raised portion 502, to move radially outward to remove the vulcanized tire from the mold. The vulcanization bladder is then contracted and peeled off.

[0078] 5. Treatment of the first raised portion:

[0079] The first method: The first method: Use physical methods, such as high-frequency vibration or impact, to decompose the first protrusion 501 into small pieces for subsequent processing and recycling.

[0080] The second method is to use a chemical method, for example, exposing the first protrusion 501 to a chemical solvent (such as methanol, acetic acid, toluene or ethyl acetate, etc.) to dissolve or decompose it into a size equivalent to that of the second protrusion 502, so that it can be completely separated from the tire base.

[0081] Figure 7 shows a schematic diagram of Example 3 of a mold for manufacturing a tread component outside the belt layer of a tire according to an embodiment of the present application. As shown in Figure 7, the third mold section 503 includes a separate first mold subsection 503a and a second mold subsection 503b. The first mold subsection 503a carries the array of the first protrusions 501 on the radially inner side for vulcanization molding the base of the hollow cavity in the tread component. The second mold subsection 503b carries the array of the second protrusions 502 on the radially inner side. The mold also includes multiple fourth mold sections 504, each of which is adapted to fit the base of the cavity so that each base can be filled after the base is vulcanized. When the base is filled with the fourth mold section 504, the second mold subsection 503b, together with the array of second protrusions 502 it carries, can be used to vulcanize and mold the neck in layers (also in steps) and connect it to the corresponding inner base to form a whole. The fourth mold portion 504 is physically or chemically decomposable so that it can be removed after the vulcanization molding of the tread assembly is completed without tearing the neck. Regarding how to make the fourth mold portion 504 physically or chemically decomposable, please refer to how to make the first raised portion 501 physically or chemically decomposable, and will not be repeated here.

[0082] FIG10 uses a small portion of a mold extending circumferentially to schematically illustrate a method for manufacturing a tire tread component outside the belt layer using the mold of Example 3 according to an embodiment of the present application, thereby making the changes in the surface structure of the tread component during the process more clearly apparent. It should be noted that in the actual process flow, an annular mold is used, obtained by circumferentially extending the small portion of the mold shown in FIG10 . Similar situations also apply to FIG11 , which will not be further described here.

[0083] As shown in FIG. 10 , the mold of Example 3 may be used to perform the following steps.

[0084] The first mold sub-section 503a is used to perform vulcanization molding with the array of the first protrusions 501 carried thereon to form the first tread portion 102a having the base portion 103a of the cavity, with the first protrusions 501 retained therein (the base portion 103a with the first protrusions 501 retained therein is not shown). The first mold sub-section 503a is moved radially outward along with the array of the first protrusions 501, thereby removing the first protrusions 501 from the base portion 103a, leaving the base portion 103a with a hollow cavity.

[0085] Each fourth mold part 504 is filled into each hollow base part 103a of the cavity.

[0086] When the base 103a is filled with the fourth mold portion 504, the second mold sub-portion 503b is used together with the array of second protrusions 502 carried thereon to be vulcanized and molded on the radial outside of the first tread portion 102a to form a second tread portion 102b having a neck 103b of the cavity, in which the second protrusion 502 is retained (the neck 103b with the second protrusion 502 retained is not shown).

[0087] The second mold sub-part 503b together with the array of second protrusions 502 are moved radially outward, thereby removing the second protrusions 502 from the neck 103b, leaving the hollow cavity neck 103b connected to the corresponding inner base 103a as a whole.

[0088] Next, the fourth mold portion 504 can be physically or chemically decomposed so that the decomposed fourth mold portion 504 can be removed through the hollow neck portion 103b without tearing the neck portion 103b, thereby forming a vulcanized rubber body having an array of multiple hollow cavities. For how to make the fourth mold portion 504 physically or chemically decomposable, please refer to how to make the first protruding portion 501 physically or chemically decomposable, and will not be further described here.

[0089] Example 2 of the manufacturing process

[0090] The vulcanization process is divided into two steps to better control the vulcanization process and improve product quality. This process also includes filling each fourth mold part 504 into each hollow base 103a of the cavity. The following is the manufacturing process:

[0091] 1. First step: vulcanization: A contracted tire vulcanization bladder is inserted into the inner side of the unvulcanized tire in the tire vulcanization mold. With the tire vulcanization mold closed, a heating medium (e.g., steam) and a pressurizing medium (e.g., nitrogen) are injected into the bladder to expand it. The bladder is pressurized to 10 bar and held for 10 minutes, then heated to 150°C and held for 15 minutes. The humidity is then controlled at 50% RH to initiate vulcanization.

[0092] 2. Secondary Vulcanization: After the initial vulcanization is complete, the tire is placed in a secondary vulcanization mold. This mold contains individual fourth mold sections 504, which are designed to fit within the hollow bases 103a of the tire cavity. This process simultaneously subjects the tire to pressure and heat from both inside and outside, ensuring a uniform vulcanization process. The final vulcanization process is completed by applying pressure to 15 bar for 15 minutes, heating to 160°C for 20 minutes, and controlling the humidity to 50% RH.

[0093] The following is a detailed description of filling each fourth mold part 504 into each hollow base portion 103a of the cavity:

[0094] During the second vulcanization process, each fourth mold section 504 is designed to precisely fit within each hollow base portion 103a of the tire's internal cavity. This means that when the tire is placed in the second vulcanization mold, each fourth mold section 504 will conform to and fill the tire's internal cavity. When the mold is closed and the vulcanization process begins, these fourth mold sections 504 will be subjected to pressure and heat, ensuring that the rubber within these hollow base portions 103a is also fully vulcanized.

[0095] For example, if the hollow base 103a of the tire's internal cavity is designed to be square, the fourth mold part 504 will be designed to be a corresponding square to accurately fill the space. Similarly, if the hollow base is designed to be round or any other shape, the fourth mold part 504 will also be designed to accommodate these shapes.

[0096] This design ensures that every part inside the tire is vulcanized evenly, thereby improving product quality and durability.

[0097] As shown in FIG12 , the tread assembly outside the belt layer of the tire is manufactured using the mold of Example 3 in the above process, with a visible lateral interface at the connection between the neck and the base. The tread assembly outside the belt layer of the tire is manufactured using the mold of Example 4 below, and also with a visible lateral interface at the connection between the neck and the base, which appears to be two layers. This is because the two manufacturing processes perform step-by-step or separate molding of the first tread portion 102a and the second tread portion 102b.

[0098] In some embodiments, when the mold of Example 3 is used to manufacture a tread assembly, during vulcanization to form the first tread portion 102a, the vulcanization time is controlled so that the rubber of the first tread portion 102a is in a state of preliminary formation but not yet fully vulcanized. This significantly enhances the shear strength of the interface.

[0099] Figure 13 illustrates the effect of different curing times on the shear strength of the interface of the first tread portion 102a (i.e., the first rubber layer) during the manufacture of a tread assembly using the mold of Example 3 according to an embodiment of the present application. As shown in Figure 13, the first tread portion 102a is initially cured for 4 minutes, leaving the first rubber layer in a pre-formed but not fully cured state. This allows the first rubber layer to crosslink with the second rubber layer during the curing of the second tread portion 102b, for example, for 10 minutes, thereby increasing the shear strength at the interface. As shown in Figure 13, curves A, B, C, and D represent the shear strength of the interface when the first rubber layer is cured once and when the second tread portion 102b is cured for the same 10-minute curing time, respectively, but with different curing times for the first rubber layer. This demonstrates that appropriately shortening the curing time of the first rubber layer, thereby reducing its degree of curing maturity, can significantly improve the shear strength of the interface.

[0100] In some embodiments, when the first tread portion 102a is formed by vulcanization, its surface is roughened and / or the roughness of the mold surface is increased. For example, the first tread portion 102a is roughened with coarse sandpaper, or a layer of coarse sandpaper is placed on the mold surface before vulcanization. This can significantly improve the shear strength of the interface compared to not adding sandpaper. As shown in Figure 14, curves A, B, and C respectively represent the shear strength of the interface when using the mold of Example 3 to manufacture the tread assembly for a single vulcanization, a two-layer vulcanization without sandpaper, and a two-layer vulcanization with sandpaper added to the mold surface. It can be seen that the shear strength of the interface is significantly improved after adding sandpaper compared to not adding sandpaper.

[0101] FIG8 is a schematic diagram of Example 4 of a mold for manufacturing a tread component outside the belt layer of a tire according to an embodiment of the present application. As shown in FIG8 , the third mold portion 503 includes a separate first mold sub-portion 503a and a second mold sub-portion 503b. The first mold sub-portion 503a carries an array of the first protrusions 501 on the radially inner side for vulcanization molding the base of the hollow cavity in the tread component and the corresponding first tread portion. The second mold sub-portion 503b carries an array of the second protrusions 502 on the radially inner side for vulcanization molding the neck of the cavity and the corresponding second tread portion, which is constructed to be tightly fitted and adhered to the outer periphery of the first tread portion.

[0102] In some embodiments, the first mold sub-portion 503a is integrally formed with the array of the first protrusions 501 , and the second mold sub-portion 503b is integrally formed with the array of the second protrusions 502 .

[0103] Figure 11 is a schematic flow chart showing a method for manufacturing a tread component outside a belt layer of a tire using the mold of Example 4 according to an embodiment of the present application. As shown in Figure 11 , the mold according to Example 4 is used to perform the following steps.

[0104] The first mold sub-portion 503a together with the array of the first protrusions 501 carried thereon is used for vulcanization molding to form the first tread portion 102a having the base 103a of the cavity, and the first protrusions 501 are removed from the base 103a by moving the first mold sub-portion 503a together with the array of the first protrusions 501 radially outward.

[0105] The second mold sub-portion 503b together with the array of the second protrusions 502 carried thereon is used for vulcanization molding to form the second tread portion 102b having the neck 103b of the cavity, and the second protrusions 502 are removed from the neck 103b by moving the second mold sub-portion 503b together with the array of the second protrusions 502 radially outward.

[0106] The second tread portion 102b having the hollow neck portion 103b is tightly fitted and adhered to the outer circumference of the first tread portion 102a having the hollow base portion 103a, thereby forming a vulcanized rubber body having an array of a plurality of hollow cavities distributed therein.

[0107] In some embodiments, when vulcanizing the first tread portion 102a, the vulcanization time is controlled so that the rubber of the first tread portion 102a is in a state of preliminary formation but not yet vulcanized, and when vulcanizing the second tread portion 102b, the vulcanization time is controlled so that the rubber of the second tread portion 102b is also in a state of preliminary formation but not yet vulcanized. Subsequently, when the second tread portion 102b is tightly fitted onto the first tread portion 102a, the strength at the interface can be enhanced by co-vulcanizing the unvulcanized rubber of the first tread portion 102a and the second tread portion 102b to induce crosslinking.

[0108] Similar to the method of manufacturing the tread component outside the belt layer of a tire using the mold of Example 3, in some embodiments, before the first tread portion 102a and the second tread portion 102b are sheathed and adhered, at least one contact surface to be adhered is roughened.

[0109] In some embodiments, when the first tread portion 102a and / or the second tread portion 102b are vulcanized to form the corresponding tread portion, the roughness of the mold surface used to form the corresponding tread portion may be increased, for example but not limited to, by adding sandpaper.

[0110] Example 3 of the manufacturing process

[0111] In Example 3 of the manufacturing process, the process of vulcanizing the two parts separately will be described in detail, and new parameter settings will be provided for a tire that is initially formed but not yet vulcanized. In addition, how to roughen at least one contact surface to be adhered will be described.

[0112] 1. First step: Vulcanization: A contracted tire vulcanization bladder is inserted into the inner side of the unvulcanized tire in the tire vulcanization mold. With the tire vulcanization mold closed, a heating medium (e.g., steam) and a pressurizing medium (e.g., nitrogen) are injected into the bladder to expand it. The new parameters are: pressurization to 8 bar for 8 minutes, heating to 120°C for 10 minutes, and humidity controlled at 45% RH for initial vulcanization.

[0113] 2. Secondary Curing: After the initial curing step, the tire is placed in a secondary curing mold. This mold includes fourth mold sections 504, which are designed to fit within the hollow base sections 103a of the tire cavity. The new parameters are: pressure to 12 bar for 12 minutes, heating to 140°C for 15 minutes, and humidity controlled at 45% RH for the final curing process.

[0114] During tire manufacturing, roughening is a key step in improving the adhesion between the tire interior and the curing bladder. This is typically achieved by physically or chemically treating at least one of the contact surfaces to be adhered.

[0115] Physical treatments typically include grinding with a grinding wheel or impact blasting. For example, the contact surface can be ground on a grinding wheel to increase its surface roughness, or impact blasted by spraying small particles onto the contact surface to create tiny surface defects, thereby increasing its surface area and improving adhesion.

[0116] Chemical treatments can involve etching the contact surface with an acid or base. For example, the contact surface can be immersed in a specific chemical solution, such as nitric acid or sodium hydroxide, which etches out tiny surface defects, thereby increasing its surface roughness.

[0117] After roughening, the contact surfaces are cleaned and prepared for adhesion to form a uniform and stable connection during the vulcanization process.

[0118] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of their solutions) can be used in combination with each other. For example, those of ordinary skill in the art may use other embodiments when reading the above description. In addition, in the above-mentioned specific embodiments, various features can be grouped together to simplify the application. This should not be interpreted as an intention that a disclosed feature that is not required to be protected is necessary for any claim. On the contrary, the subject matter of the present invention may be less than all the features of a specific disclosed embodiment. Thus, the following claims are incorporated into the specific embodiments as examples or embodiments, wherein each claim is independently a separate embodiment, and it is considered that these embodiments can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the appended claims and the full scope of equivalents to which these claims are entitled.

Claims

1. A tread component outside the belt layer of a tire, characterized in that, it includes: a vulcanized rubber body; and an array of a plurality of hollow cavities distributed on the vulcanized rubber body, each cavity including a neck recessed inwardly from the outer surface of the vulcanized rubber body and a base integrally connected to the inner side of the neck, and a first ratio of the maximum cross-sectional area of the base to the cross-sectional area of the neck being greater than 5:

1.

2. The tread component according to claim 1, characterized in that, the first ratio of the maximum cross-sectional area of the base to the cross-sectional area of the neck is greater than or equal to 10:

1.

3. The tread component according to claim 1, characterized in that, the first ratio of the average cross-sectional area of the base to the cross-sectional area of the neck is greater than or equal to 23:

1.

4. The tread component according to claim 1, characterized in that, the cavity serves as a sound absorption chamber, and the cross-sectional area of the neck, the length of the neck and the volume of the base are configured such that the cavity can absorb noise in a frequency range below 5 kHz.

5. The tread component according to claim 1, characterized in that, the cavity serves as a sound absorption chamber, and the cross-sectional area of the neck, the length of the neck and the volume of the base are configured such that the frequency range that the cavity can absorb is adapted to the peak frequency of the radiated noise of the tire.

6. The tread component according to claim 5, characterized in that, the cross-sectional area of the neck, the length of the neck and the volume of the base are configured such that the frequency range that the cavity can absorb reaches 800 Hz, or reaches 500 Hz.

7. The tread component according to claim 1, characterized in that, the cavity serves as a sound absorption chamber, and the cross-sectional area of the neck, the length of the neck and the volume of the base are configured such that the sound absorption coefficient of the array of cavities for the peak frequency of the radiated noise of the tire is greater than or equal to 0.

4.

8. The tread component according to claim 1, characterized in that, a second ratio of the cross-sectional area of the neck to the length of the neck and a third ratio with respect to the volume of the base are set according to the following formula (1): f = c / 2π √(S / Vl) Formula (1) wherein, f represents the frequency range that the cavity is intended to absorb, c represents the speed of sound, S represents the cross-sectional area of the neck, l represents the length of the neck, V represents the volume of the base, the second ratio is S / l, and the third ratio is S / Vl.

9. The tread component according to claim 1, characterized in that, the neck and the base have a preset included angle range at the connection, and within the preset included angle range, using the direct demolding method will cause cracking or tearing at the connection of the neck and the base and / or the neck.

10. The tread component according to claim 1, characterized in that, there is no tearing at the connection of the neck and the base and the neck.

11. The tread component according to claim 1, characterized in that, The transverse shear strength of the cross-section at the connection of the neck and the base of the tread component is 1.3 Mpa - 1.5 Mpa.

12. The tread component according to claim 1, wherein, after vulcanization, the ratio of the volume of the residual rubber attached to the inner wall of the base to the volume of the base is less than 4%.

13. The tread component according to claim 1, wherein, the depth of the cavity in the longitudinal direction is set according to the thickness of the tread component of the tire and the absorption frequency range of the cavity, such that the depth is less than 80% of the thickness of the tread component, and for a second absorption frequency range lower than the first absorption frequency range, the corresponding second depth is greater than the first depth corresponding to the first absorption frequency range.

14. For the tread component according to claim 13, the depth of the cavity in the longitudinal direction can reach the thickness of the tread component minus 1 mm.

15. The tread component according to claim 1, wherein, a visible transverse interface is formed at the connection of the neck and the base.

16. A tire, wherein, it includes a belt layer and a tread component according to any one of claims 1 - 10 outside the belt layer.

17. A mold for a tread component outside the belt layer for manufacturing a tire, wherein, it includes: a first mold part, the first mold part includes an array of first protrusions arranged circumferentially, and is used for vulcanizing and molding the base of the hollow cavity in the tread component; a second mold part, the second mold part includes an array of second protrusions arranged circumferentially, and is used for vulcanizing and molding the neck of the hollow cavity in the tread component and connecting the neck to the corresponding inner base as a whole, thereby vulcanizing and molding an array of multiple hollow cavities distributed on the vulcanized rubber body; a third mold part, the third mold part is configured to carry the array of the first protrusions and the array of the second protrusions on the radial inner side, wherein, the first ratio of the maximum cross-sectional area of the first protrusion to the cross-sectional area of the second protrusion is greater than 5:

1.

18. The mold according to claim 17, wherein, the third mold part is configured to carry the array of the second protrusions and the array of the first protrusions on the radial inner side in sequence, and the first protrusion is physically or chemically decomposable so as to be removed without tearing the neck after the vulcanization and molding of the tread component.

19. The mold according to claim 17, wherein, the third mold part includes a discrete first mold sub-part and a second mold sub-part, the first mold sub-part carries the array of the first protrusions on the radial inner side for vulcanizing and molding the base of the hollow cavity in the tread component, the mold further includes a plurality of fourth mold parts, and each fourth mold part is adapted to each base of the cavity so as to fill each base after the base is vulcanized and molded. The second die sub - part bears an array of the second protrusions on the radially inner side so as to vulcanize and mold a neck when the base is filled with the fourth die part and connect it integrally with the corresponding inner base, wherein the fourth die part is physically or chemically decomposable so as to be removed without tearing the neck after the vulcanization molding of the tread component is completed.

20. The die according to claim 17, wherein, the third die part includes discrete first and second die sub - parts, the first die sub - part bears an array of the first protrusions on the radially inner side for vulcanizing and molding a base of a hollow cavity and a corresponding first tread part in the tread component, the second die sub - part bears an array of the second protrusions on the radially inner side so as to vulcanize and mold a neck of the cavity and a corresponding second tread part, and the second tread part is configured to tightly sleeve and adhere to the outer periphery of the first tread part.

21. The die according to claim 18, wherein, the third die part and the array of the second protrusions are integrally formed, the array of the first protrusions and the array of the second protrusions are integrally formed, or are detachably connected and fixed to the array of the second protrusions.

22. The die according to claim 19 or 20, wherein, the first die sub - part and the array of the first protrusions are integrally formed, and the second die sub - part and the array of the second protrusions are integrally formed.

23. A method for manufacturing a tread component outside the belt layer of a tire, wherein, it includes performing the following steps using the die according to claim 18: Performing vulcanization molding using the die to integrally form a vulcanized rubber body with an array of a plurality of hollow cavities, and the second protrusions are retained in the necks of the cavities and the first protrusions are retained in the bases; Moving the third die part together with the second protrusions radially outward, thereby removing the second protrusions and leaving hollow necks; Physically or chemically decomposing the first protrusions, so that the decomposed first protrusions are removed through the hollow necks without tearing the necks.

24. A method for manufacturing a tread component outside the belt layer of a tire, wherein, it includes performing the following steps using the die according to claim 19: Performing vulcanization molding using the first die sub - part together with the array of the first protrusions borne thereon to form a first tread part having a base of the cavity, and the first protrusions are retained in the base; Removing the first protrusions from the base by moving the first die sub - part together with the array of the first protrusions radially outward, leaving a base of the hollow cavity; Filling each of the hollow bases of the cavities with each of the fourth die parts; Performing vulcanization molding on the radially outer side of the first tread part using the second die sub - part together with the array of the second protrusions borne thereon in the case where the base is filled with the fourth die part to form a second tread part having a neck of the cavity, and the second protrusions are retained in the neck; By moving the second die sub - part together with the array of second protrusions radially outward, the second protrusions are removed from the neck, leaving a hollow - necked cavity and integrally connecting it to the corresponding inner base; Physically or chemically decomposing the fourth die part so that the decomposed fourth die part is removed via the hollow neck without tearing the neck, thereby forming a vulcanized rubber body with an array of multiple hollow cavities distributed therein.

25. The manufacturing method according to claim 24, wherein, further comprising: When vulcanizing to form the first tread surface, controlling the vulcanization time such that the rubber of the first tread surface is in a state of being preliminarily formed but not fully vulcanized.

26. The manufacturing method according to claim 24, wherein, further comprising: When vulcanizing to form the first tread surface, roughening its surface and / or increasing the roughness of the die surface used.

27. A manufacturing method of a tread component outside the belt layer of a tire, wherein, comprising performing the following steps using the die according to claim 20: Using the first die sub - part together with the carried array of first protrusions for vulcanization molding to form a first tread surface having the base of the cavity, and by moving the first die sub - part together with the array of first protrusions radially outward, the first protrusions are removed from the base; Using the second die sub - part together with the carried array of second protrusions for vulcanization molding to form a second tread surface having the neck of the cavity, and by moving the second die sub - part together with the array of second protrusions radially outward, the second protrusions are removed from the neck; Tightly sleeving and adhering the second tread surface with a hollow neck onto the outer periphery of the first tread surface with a hollow base, thereby forming a vulcanized rubber body with an array of multiple hollow cavities distributed therein.

28. The manufacturing method according to claim 27, wherein, further comprising: When vulcanizing to form the first tread surface, controlling the vulcanization time such that the rubber of the first tread surface is in a state of being preliminarily formed but not fully vulcanized, and when vulcanizing to form the second tread surface, controlling the vulcanization time such that the rubber of the second tread surface is in a state of being preliminarily formed but not fully vulcanized; enhancing the strength at the interface by co - vulcanizing the first tread surface and the second tread surface with un - fully vulcanized rubber to initiate cross - linking.

29. [Corrected according to Rule 91 on 08.12.2023] The manufacturing method according to claim 27, wherein, further comprising: Before sleeving and adhering the first tread surface and the second tread surface, roughening at least one contact surface to be adhered.

30. [Corrected according to Rule 91 on 08.12.2023] The manufacturing method according to claim 27, wherein, further comprising: When vulcanizing to form the first tread surface and / or the second tread surface, increasing the roughness of the die surface used to form the corresponding tread surface.

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