Tire capable of conveniently measuring sidewall wear and working method

Abstract

The invention provides a tire capable of conveniently measuring sidewall wear and a working method, relates to the field of tires, and aims to solve the problem that the sidewall of a bus tire is easy to excessively wear and is inconvenient to monitor at present, a resistance wire is adopted as a core detection element, is of a U-shaped structure and is embedded into a convex position of a sidewall rubber layer, and compared with a multi-layer sensor with a complex tread, the tire is more convenient to monitor. The tire sidewall structure is simple in structure and small in occupied space, the problem that the tire sidewall strength is weakened due to the fact that the size of an element is too large is solved, when a tire sidewall rubber layer is abraded, the protruding part of the annular end face of the tire sidewall rubber layer is gradually reduced along with abrasion, the resistance wire embedded in the tire sidewall rubber layer is synchronously abraded due to abrasion of the rubber layer, and the effective length of the resistance wire is gradually shortened. Due to the fact that the resistance value and the length of the resistance wire have the corresponding relation, the real-time resistance value of the resistance wire is measured through the detection circuit, the abrasion thickness of the sidewall rubber layer can be reversely deduced by combining the pre-calibrated corresponding relation of the length of the resistance wire, the resistance value and the thickness of the sidewall rubber layer, and quantitative monitoring is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of tires, in particular to a tire for conveniently measuring sidewall wear and a working method. BACKGROUND

[0002] The need to monitor the condition of vehicle tires is critical to saving fuel, reducing downtime, and reducing accidents caused by tire failure. Current monitoring of the condition of vehicle tires focuses on the tire tread wear condition, a tread wear indicator inserted into the inner side of the tire. The indicator is configured as a plurality of radially stacked sensor elements that are operatively configured and positioned to respond to progressive tread wear of the corresponding tread element by sequentially sacrificially abrading and undergoing a change in electrical resistance. The sensor elements are connected by an electrical circuit that communicates data signals from the sensor elements to a data processor that indicates the change in cumulative resistivity of the sensor elements. The data processor receives the data signals from the sensor elements and determines the radial wear level of the tread element based on the data signals.

[0003] For a bus tire, the sidewall is the weakest part of the tire, and the bus is in the working condition of frequent starting and stopping, and the bus tire is easily cracked, bulged or excessively worn due to long-term bending and road edge scraping. Cracks and bulges can be found by direct observation, but it is difficult to monitor the excessive wear quantitatively. Since the main wear position of the tread is the pattern block, the pattern block has enough thickness for a more complex sensor element to be embedded, and the sidewall is thinner than the tread. Without the protection of the tread pattern, the strength is mainly maintained by the rubber layer and the internal cord layer. A complex sensor element will occupy more space, resulting in a larger weak area in the sidewall, which is not suitable for wear detection of the sidewall and affects the safety of the tire. SUMMARY

[0004] The purpose of the present application is to overcome the defects of the prior art and provide a tire for conveniently measuring sidewall wear and a working method. The resistance wire adopts a U-shaped structure and is embedded in the protruding position of the sidewall rubber layer. Compared with the complex multi-layer sensor of the tread, the structure is simple and occupies less space, avoiding the problem of weakened sidewall strength caused by the large size of the element. It is suitable for the characteristics of the thin sidewall.

[0005] The first purpose of the present application is to provide a tire for conveniently measuring sidewall wear, which adopts the following scheme: The tire comprises a resistance wire embedded in the protruding position of the annular end surface of the sidewall rubber layer. The resistance wire is in a U-shaped structure, with one side blocked and embedded in the sidewall rubber layer, and the other side with two exposed contact points on the annular end surface of the sidewall rubber layer for connecting to a detection circuit to form a closed loop. The resistance wire gradually shortens with the wear of the sidewall rubber layer. The wear of the sidewall of the tire is obtained according to the corresponding relationship between the length of the resistance wire, the resistance value of the resistance wire and the thickness of the sidewall rubber layer.

[0006] Furthermore, the resistance wire is provided in multiple strands, which are distributed at intervals along the tire sidewall ring upwards.

[0007] Furthermore, the length between the contacts at both ends of the resistance wire is the total length of the resistance wire, and the contacts are gradually renewed as the tire sidewall rubber layer wears down, thus maintaining exposure.

[0008] Furthermore, the resistance wire and the sidewall rubber layer are distinguished by different colors.

[0009] Furthermore, the resistance wire includes a first segment, a second segment, and a third segment in sequence according to the U-shaped bending path. The first segment and the third segment are straight segments and perpendicular to the annular end face of the tire sidewall rubber layer. One end of the first segment and the third segment respectively forms a contact point. The ends of the first segment and the third segment inside the tire sidewall rubber layer are connected through the second segment.

[0010] Furthermore, the two contacts at both ends of the resistance wire are distributed separately.

[0011] Furthermore, the resistance wires are respectively arranged in the rubber layers on the sidewalls at both ends of the tire.

[0012] A second objective of the present invention is to provide a method for measuring tire sidewall wear, utilizing a tire for convenient measurement of sidewall wear as provided in the first objective, comprising: Tires that allow for easy measurement of sidewall wear are installed on vehicles; Periodically connect the testing equipment to the contacts of the resistance wire to form a closed circuit, and calculate the resistance value of the resistance wire; The remaining length of the resistance wire is calculated based on the relationship between the resistance value and the length of the resistance wire, and the thickness of the tire sidewall rubber layer is obtained based on the relationship between the length of the resistance wire and the thickness of the tire sidewall rubber layer. Determine the wear condition of the rubber layer on the tire sidewall.

[0013] Furthermore, the correspondence between the resistance value of the resistance wire, the length of the resistance wire, and the thickness of the rubber layer on the tire sidewall is pre-calibrated.

[0014] Furthermore, once the resistance of the heating wire reaches the set value, the tire is replaced.

[0015] Compared with the prior art, the advantages and positive effects of this invention are: To address the issue of excessive wear on bus tire sidewalls that is difficult to monitor, a resistance wire with a U-shaped structure is used as the core detection element. This wire is embedded in the raised portion of the sidewall rubber layer. Compared to the complex multi-layer sensors on the tire tread, its structure is simpler and occupies less space, avoiding the problem of weakened sidewall strength due to excessive component size. It is also suitable for the thinner sidewall. As the sidewall rubber layer wears, the raised portion of its annular end face gradually decreases, and the embedded resistance wire is simultaneously eroded by the rubber layer, causing the effective length of the resistance wire to gradually shorten. Since there is a correlation between the resistance value and the length of the resistance wire, the real-time resistance value of the resistance wire is measured by the detection circuit. Combined with the pre-calibrated correlation between the resistance wire length, resistance value, and sidewall rubber layer thickness, the wear thickness of the sidewall rubber layer can be deduced, achieving quantitative monitoring.

[0016] The resistance wires are not single strands, but rather multiple wires spaced at intervals along the circumferential direction of the tire sidewall, covering the entire annular area. This avoids monitoring errors caused by localized abnormal wear of a single resistance wire, such as excessive scratching in a particular location. The resistance wires are a different color from the tire sidewall rubber layer, allowing for visual identification of the wire's exposure level and aiding in the assessment of wear progress.

[0017] Resistance wires are arranged in the rubber layers on both sides of the tire, which can simultaneously monitor the wear of both sides of the tire. This adapts to the differential wear that may exist on the two sides of the tire and can cope with the working conditions of buses that frequently pull over to the side of the road, resulting in more severe wear on one side. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0019] Fig. 1 This is a schematic diagram of a tire for convenient measurement of sidewall wear in one or more embodiments of the present invention; Fig. 2 This is a schematic diagram of the end face of a tire in one or more embodiments of the present invention; Fig. 3 This is a schematic diagram of the resistance wire embedded in the tire sidewall rubber layer in one or more embodiments of the present invention; Among them, 1. Tread; 2. Resistance wire; 3. Protrusion on the annular end face of the sidewall rubber layer; 4. Sidewall rubber layer; 5. Sidewall; 6. Contact point. Detailed Implementation

[0020] Example 1 In a typical embodiment of the present invention, such as Figs. 1-3 As shown, a convenient method for measuring tire sidewall wear is presented.

[0021] Bus tires suffer from the problem of difficulty in quantitatively monitoring excessive wear on the sidewall (5). Due to the special operating conditions, the sidewall (5) of bus tires is prone to excessive wear. However, the sidewall (5) is thin and lacks tread protection, relying on the rubber layer and internal ply layer for strength. Using complex sensor elements found in the tread layer (1) would occupy too much space, creating a weak area on the sidewall (5) and affecting tire safety. Furthermore, existing technologies lack effective quantitative methods for measuring excessive wear on the sidewall (5), only allowing direct observation to detect cracks and bulges, without accurately determining the degree of wear. Therefore, this embodiment provides a tire for conveniently measuring sidewall wear. The resistance wire (2) adopts a U-shaped design and is embedded in the protruding position of the sidewall rubber layer (4). Compared to the complex multi-layer sensor in the tread layer (1), its structure is simple and occupies less space, avoiding the problem of excessive weakening of the sidewall (5) due to excessive component size, thus achieving convenient and quantitative monitoring of sidewall (5) wear.

[0022] The tire for convenient sidewall wear measurement includes a tire body and a resistance wire 2. The resistance wire 2 is the core detection element and has a U-shaped structure. The U-shaped sealed side of the resistance wire 2 is embedded in the sidewall rubber layer 4, and the two ends of the open side are contact points 6 exposed on the annular end face of the sidewall rubber layer 4, which are used to connect to the detection circuit to form a closed loop. The resistance wire 2 is embedded in the protrusion 3 position on the annular end face of the sidewall rubber layer.

[0023] like Fig. 3 As shown, the resistance wire 2 adopts a U-shaped design and is embedded in the protrusion 3 of the annular end face of the tire sidewall rubber layer. Compared with the complex multi-layer sensor of the tread 1, its structure is simple and occupies less space, avoiding the problem of weakening the strength of the tire sidewall 5 due to excessive component size, and adapting to the thinner characteristics of the tire sidewall 5. When the tire sidewall rubber layer 4 wears, the protrusion 3 of the annular end face of the tire sidewall rubber layer is the structure that first comes into contact with the outside. For example, when parking on the side of the road, the protrusion 3 of the annular end face of the tire sidewall rubber layer rubs against the curb. The length of the resistance wire 2 gradually decreases with wear, and the resistance wire 2 embedded in it will be eroded synchronously due to the wear of the rubber layer, resulting in a gradual shortening of the effective length of the resistance wire 2. Since there is a corresponding relationship between the resistance value of the resistance wire 2 and its length, under the same material, the shorter the length, the smaller the resistance value. By measuring the real-time resistance value of the resistance wire 2 through the detection circuit and combining it with the pre-calibrated correspondence between the length of the resistance wire 2, resistance value, and thickness of the tire sidewall rubber layer 4, the wear thickness of the tire sidewall rubber layer 4 can be deduced, realizing quantitative monitoring.

[0024] By correlating the length of the resistance wire 2 with its resistance value, the phenomenon of excessive wear on the tire sidewall 5, which is difficult to quantify intuitively, is transformed into a measurable resistance signal. This accurately reflects the degree of wear on the tire sidewall 5, overcoming the limitation of quantitative analysis based solely on observation. A simple U-shaped resistance wire 2 structure is used, embedded in the protruding position, avoiding the encroachment of complex components on the space of the tire sidewall 5, and preserving the original strength of the tire sidewall rubber layer 4 and the ply layer, thus ensuring tire safety. Addressing the characteristic of easy wear on the tire sidewall 5 of buses, this provides a convenient monitoring method that can promptly detect excessive wear problems, reduce accidents or downtime caused by tire sidewall 5 malfunctions, and improve operational safety and efficiency.

[0025] like Fig. 1 , Fig. 2 As shown, multiple resistance wires 2 are distributed circumferentially at intervals. The resistance wires 2 are not single, but multiple are arranged circumferentially at intervals along the tire sidewall 5. This covers the annular area of ​​the tire sidewall 5, avoiding monitoring deviations caused by localized abnormal wear of a single resistance wire 2 (such as excessive scratching at a certain position).

[0026] A single resistance wire 2 can only reflect localized wear, while multiple resistance wires 2 distributed circumferentially can simultaneously monitor wear at different locations on the tire sidewall 5. When wear occurs at a certain location, the length of the corresponding resistance wire 2 shortens and its resistance changes. By comparing multiple sets of data, interference from localized abnormal wear can be eliminated, and the average wear level of the entire tire sidewall 5 can be more accurately reflected, solving the problem of the limitations of single-point monitoring.

[0027] The length between the contacts 6 at both ends of the resistance wire 2 is the total length. As the rubber layer 4 on the tire sidewall wears down, the resistance wire 2 will gradually become shorter. The exposed resistance wire 2 after wear will form new contacts 6, and the contacts 6 will be gradually renewed and kept exposed. That is, when the surface of the tire sidewall 5 wears down, the original contacts 6 are eroded, but new contacts 6 will be exposed as the rubber layer peels off, ensuring a continuous connection with the detection circuit.

[0028] The resistance wire 2 is a different color from the sidewall rubber layer 4. The degree of exposure of the resistance wire 2 can be intuitively identified through visual difference, which helps to judge the wear progress.

[0029] The resistance wire 2 is divided into three segments—the first, the second, and the third—following a U-shaped path. The first and third segments are straight sections perpendicular to the annular end face of the sidewall 5, forming contact points 6 at both ends. The second segment connects the first two segments inside the sidewall 5. This segmented design makes the wear path of the resistance wire 2 more regular, and the relationship between its length variation and the wear of the sidewall 5 thickness more stable.

[0030] The two contacts 6 at both ends do not touch each other, ensuring that an effective closed loop is formed when connected to the detection circuit, avoiding short circuit interference with resistance measurement.

[0031] Resistance wires 2 are arranged on both sides of the tire sidewall rubber layer 4, which can simultaneously monitor the wear of both sides of the tire sidewall 5 and adapt to the differential wear that may exist on both sides of the vehicle, such as the more severe wear on one side due to the frequent pulling of buses to the side.

[0032] During the wear process of the tire sidewall 5, the surface rubber layer is continuously peeled off. If the contact 6 remains fixed, it may be disconnected from the circuit due to wear. However, the design of the contact 6 gradually being renewed and kept exposed as it wears off ensures that the resistance wire 2 can always be connected to the detection circuit, forming a closed loop. For example, when the exposed parts of the first and third sections are eroded, the parts embedded in the rubber layer become new contacts 6 as the rubber peels off, maintaining the continuity of resistance measurement and avoiding monitoring interruptions due to contact 6 failure.

[0033] The color difference between the resistance wire 2 and the rubber layer allows for quick visual identification of the exposed length of the resistance wire 2. When the rubber layer wears down to the point where the resistance wire 2 is exposed, the wear depth can be intuitively judged through color comparison, which can be corroborated with the resistance measurement results, thus improving the reliability of monitoring. It can also serve as a backup judgment basis, especially when detecting temporary circuit faults.

[0034] The first and third segments are perpendicular to the annular end face of the sidewall 5. Their length changes are directly related to the radial wear thickness of the sidewall rubber layer 4 (1 mm of wear corresponds to a 1 mm shortening of the resistance wire 2). The second segment is located inside the sidewall 5 and does not directly contact the wear surface. This ensures that the total length change of the resistance wire 2 is determined only by the wear of the sidewall 5 surface. This makes the correspondence between the length of the resistance wire 2, the resistance value, and the thickness of the sidewall 5 more linear and easier to calibrate, reducing measurement errors caused by structural irregularities.

[0035] The wear on the tire sidewalls 5 on both sides of the bus may vary due to parking habits, road conditions, etc. The resistance wires 2 are installed on each side to independently monitor the wear of each side, avoiding the omission of hidden dangers on the other side due to monitoring on only one side, and ensuring that there are no blind spots in the safety monitoring of the tire sidewalls 5.

[0036] The circumferential distribution of multiple resistance wires 2 and the linear correspondence of the segmented structure enable the measurement results to better reflect the overall wear level of the tire sidewall 5, reducing local errors. The dual-sided arrangement covers the differentiated wear on both sides of the tire, improving the comprehensiveness of monitoring. The dynamic updating design of the contacts 6 ensures that the circuit remains connected during the wear process, avoiding monitoring interruptions; the phased distribution of the contacts 6 prevents the risk of short circuits and ensures the accuracy of resistance measurement. The color-coded visual aid allows operators to quickly judge the wear status by appearance, forming a dual verification with electronic monitoring. The overall structure remains simple, without increasing the volume of too many components, maintaining the original strength of the tire sidewall 5, and adapting to the thin and easily worn working conditions of bus tire sidewalls 5.

[0037] Example 2 In another typical embodiment of the present invention, such as Figs. 1-3 As shown, a working method for measuring tire sidewall wear is provided, using a tire with convenient sidewall wear measurement as described in Example 1.

[0038] A method for measuring tire sidewall wear includes: Tires that allow for easy measurement of sidewall wear are installed on vehicles; Periodically connect the testing equipment to the contact 6 of the resistance wire 2 to form a closed circuit, and calculate the resistance value of the resistance wire 2; The remaining length of the resistance wire 2 is calculated based on the correspondence between the resistance value and the length of the resistance wire 2, and the thickness of the tire sidewall rubber layer 4 is obtained based on the correspondence between the length of the resistance wire 2 and the thickness of the tire sidewall rubber layer 4. Determine the wear condition of the rubber layer 4 on the tire sidewall.

[0039] Specifically, in combination Figs. 1-3 The working method for measuring tire sidewall wear is described in detail in Example 1.

[0040] The tire described in the first purpose, which is convenient for measuring sidewall wear, is installed on the vehicle. White resistance wires 2 are vertically embedded in the semi-finished tire sidewall 5. The first and third segments are at 90° to the sidewall 5, fixed by high-temperature vulcanization, and arranged equally along the circumference 6 of the sidewall 5.

[0041] The correspondence between the resistance value (R) and length (L) of resistance wire 2 and the thickness of the sidewall rubber layer 4 is pre-calibrated to establish a basic data model. Based on the resistance formula R=ρL / S, when the material (ρ) and cross-sectional area (S) are fixed, R and L are linearly related.

[0042] Before and after the bus departs, a handheld resistance measuring device, such as a multimeter, is used to measure and record the resistance value by placing it on the white resistance wire 2 (position 5) on the tire sidewall and connecting it to contact 6 of resistance wire 2 to form a closed circuit. The measured resistance data is then sent to a backend system for centralized data management.

[0043] Based on the pre-calibrated correspondence, the remaining length of the resistance wire 2 is deduced from the resistance value, and then converted into the remaining thickness of the tire sidewall rubber layer 4 to determine the wear condition. When the resistance value of the resistance wire 2 reaches the set value (corresponding to the remaining thickness of the tire sidewall 5 being lower than the safety threshold), a tire replacement command is triggered; combined with wear data and operating condition information (such as route and driving habits), intelligent analysis and optimization are performed.

[0044] The material (ρ) and cross-sectional area (S) of the resistance wire 2 are fixed. According to the resistance formula R=ρL / S, the resistance value (R) is directly proportional to the length (L). When the sidewall 5 wears, the resistance wire 2 wears down synchronously with the rubber layer. The decrease in length (L) leads to a decrease in resistance (R). Therefore, the change in L can be directly inferred by measuring R. The remaining length of L is directly related to the remaining thickness of the sidewall rubber layer 4. Since the resistance wire 2 is perpendicularly embedded in the sidewall 5, the change in length is equal to the wear thickness of the sidewall 5, thus achieving a quantitative conversion between resistance value, length, and thickness.

[0045] For bus tires, regular monitoring can be performed, with drivers taking measurements before departure and after returning to the city, covering the state before and after a single operation. This can capture short-term wear changes (such as abnormal wear caused by scratches during a single trip). The resistance wires 2 arranged in 6 equal parts around the circumference ensure that the measurement points cover the entire circumference of the tire sidewall 5, avoiding local missed detections.

[0046] After the measurement data is uploaded to the backend, it is not only used to judge the wear and tear in real time, but also linked with the vehicle's GPS route, operation records, etc. to form a multi-dimensional database, providing support for long-term analysis.

[0047] By setting a safe threshold for the resistance value of resistance wire 2 (corresponding to a remaining thickness of ≥4mm on the tire sidewall 5), a replacement command is triggered when the measured value reaches the threshold, turning passive response to faults into active prevention. For example, it avoids tire blowout caused by the tire sidewall 5 wearing down to the ply layer, while ensuring that the tire is used to its maximum extent within a safe range.

[0048] Measurements can be completed using a handheld device, requiring no specialized tools or complex training, making it suitable for daily bus operations. The white resistance wire 2 and tire sidewall 5 are clearly distinguishable by color, facilitating quick location of measurement points. Quantitative calculations based on the resistance formula avoid subjective judgment errors, and pre-calibrated correspondences ensure measurement accuracy, solving the problem of quantification inherent in traditional visual inspection. Through precise monitoring, tires can be replaced within safe thresholds (e.g., remaining thickness ≥ 4mm), increasing utilization by 20%~30% and avoiding resource waste caused by overly conservative replacement practices.

[0049] By combining resistance measurement data with GPS routes, the impact of specific road sections (such as those with many curves or rough curbs) on tire sidewall wear can be analyzed, allowing for the optimization of operating routes. Furthermore, by comparing vehicle wear data from different drivers, targeted driving habit training can be conducted, such as reducing frequent scrapes from pulling over to the side of the road. This forms a closed loop of measurement, analysis, and optimization, shifting tire maintenance from experience-driven to data-driven approaches and improving the overall operational efficiency of the public transportation system.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tire for convenient measurement of sidewall wear, characterized in that, It includes a resistance wire, which is embedded in the protruding part of the annular end face of the tire sidewall rubber layer. The resistance wire is U-shaped, with one side sealed and buried in the tire sidewall rubber layer, and the two ends of the open side exposed to the annular end face of the tire sidewall rubber layer as contacts are connected to the detection circuit to form a closed loop. The resistance wire gradually shortens as the tire sidewall rubber layer wears. The wear condition of the tire sidewall is obtained based on the corresponding relationship between the length of the resistance wire, the resistance value of the resistance wire and the thickness of the tire sidewall rubber layer.

2. The tire for convenient measurement of sidewall wear as described in claim 1, characterized in that, The resistance wire is provided in multiple strands, which are distributed at intervals along the tire sidewall ring upwards.

3. The tire for convenient measurement of sidewall wear as described in claim 2, characterized in that, The length between the contacts at both ends of the resistance wire is the total length of the resistance wire. As the rubber layer on the tire sidewall wears down, the contacts are gradually renewed, keeping them exposed.

4. The tire for convenient measurement of sidewall wear as described in claim 1, characterized in that, The resistance wire and the sidewall rubber layer are distinguished by different colors.

5. The tire for convenient measurement of sidewall wear as described in claim 1 or 4, characterized in that, The resistance wire includes a first segment, a second segment, and a third segment in sequence according to the U-shaped bending path. The first segment and the third segment are straight segments and perpendicular to the annular end face of the tire sidewall rubber layer. One end of the first segment and the third segment respectively forms a contact point. The ends of the first segment and the third segment inside the tire sidewall rubber layer are connected through the second segment.

6. The tire for convenient measurement of sidewall wear as described in claim 5, characterized in that, The two contacts at both ends of the resistance wire are distributed separately.

7. The tire for convenient measurement of sidewall wear as described in claim 6, characterized in that, The resistance wires are arranged in the rubber layers on the sidewalls at both ends of the tire.

8. A method for measuring tire sidewall wear, utilizing a tire for convenient sidewall wear measurement as described in any one of claims 1-7, characterized in that, include: Tires that allow for easy measurement of sidewall wear are installed on vehicles; Periodically connect the testing equipment to the contacts of the resistance wire to form a closed circuit, and calculate the resistance value of the resistance wire; The remaining length of the resistance wire is calculated based on the relationship between the resistance value and the length of the resistance wire, and the thickness of the tire sidewall rubber layer is obtained based on the relationship between the length of the resistance wire and the thickness of the tire sidewall rubber layer. Determine the wear condition of the rubber layer on the tire sidewall.

9. The working method for conveniently measuring tire sidewall wear as described in claim 8, characterized in that, The correspondence between the resistance value of the resistance wire, the length of the resistance wire, and the thickness of the rubber layer on the tire sidewall is pre-calibrated.

10. The working method for conveniently measuring tire sidewall wear as described in claim 8, characterized in that, Once the resistance of the heating wire reaches the set value, the tire is replaced.

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