Tire management device, program and tire management method

Abstract

To provide a tire management device, a program, and a tire management method, which can determine a deterioration state through a simple calculation.SOLUTION: A tire management device (10) comprises: an acquisition unit (131) for acquiring input data including information regarding a state of a tire detected by a detection device mounted on a vehicle; a calculation unit (132) for calculating a speed related deterioration index, which is a deterioration index of the tire related to the speed of the vehicle, based on the input data, for calculating a first load-related deterioration index, which is the deterioration index of the tire related to a load according to a fitting position of the tire; and for calculating a second load-related deterioration index, which is the deterioration index of the tire related to the load of the vehicle; and a determination unit (133) that determines a deterioration state of the tire based on the speed related deterioration index, the first load-related deterioration index, and the second load-related deterioration index.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a tire management device, a program, and a tire management method. [Background technology]

[0002] Conventionally, there is known a system that acquires data detected by a vehicle while it is moving and estimates tire deterioration. For example, Patent Document 1 discloses a tire management device including a deterioration state prediction means that predicts the deterioration tendency and deterioration state of tires mounted on a vehicle for each mounting position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-218097 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the tire management device of Patent Document 1 appropriately manages tires to average the period of use of each tire, but there is a demand for quickly determining a specific deterioration state with sufficient accuracy by simple calculations using less data. For example, there is a demand for quickly determining the deterioration state of a base tire and whether or not it can be retreaded. Here, retreading refers to scraping the surface of the tread rubber of a tire and applying new rubber to reuse it. The base tire is the part of the tire (the part to be reused) excluding the tread portion that is replaced in the retreading.

[0005] In view of the above circumstances, an object of the present disclosure is to provide a tire management device, a program, and a tire management method that can determine the deterioration state through simple calculations. [Means for solving the problem]

[0006] (1) A tire management device according to an embodiment of the present disclosure includes: an acquisition unit that acquires input data including information regarding a tire condition detected by a detection device mounted on the vehicle; a calculation unit that calculates, based on the input data, a speed-related deterioration index that is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index that is a deterioration index of the tire related to a load corresponding to a mounting position of the tire, and a second load-related deterioration index that is a deterioration index of the tire related to a load corresponding to a load amount of the vehicle; The tire degradation state determining unit determines a degradation state of the tire based on the speed-related degradation indicator, the first load-related degradation indicator, and the second load-related degradation indicator. With this configuration, the deterioration state of the tire can be determined by simple calculation.

[0007] (2) As an embodiment of the present disclosure, in (1), The calculation unit calculates a low internal-pressure running deterioration index, which is a deterioration index indicating whether or not the vehicle has run in a state where the internal pressure of the tire is low, based on the input data; and The determination unit determines a deterioration state of the tire based on the speed-related deterioration index, the first load-related deterioration index, the second load-related deterioration index, and the low-inner-pressure running deterioration index. With this configuration, the deterioration state of the tire can be determined taking into account low internal pressure running, which causes significant deterioration of the base tire.

[0008] (3) As an embodiment of the present disclosure, in (2), When the input data includes position information of the vehicle, the calculation unit distinguishes between a running state and a stopped state of the vehicle based on the position information, and when the input data does not include position information of the vehicle but includes temperature information of the tires, the calculation unit distinguishes between a running state and a stopped state of the vehicle based on the tire temperature rising above a specific value. With this configuration, it is possible to accurately distinguish between a moving state and a stopped state of the vehicle based on the acquired information.

[0009] (4) As an embodiment of the present disclosure, in any one of (1) to (3), the input data includes location information of the vehicle; The calculation unit calculates the speed-related deterioration index by distinguishing whether the road on which the vehicle has traveled is an expressway or an ordinary road based on the position information. This configuration allows the speed-related degradation index to be calculated accurately.

[0010] (5) As an embodiment of the present disclosure, in any one of (1) to (4), The tire mounting positions used for calculating the first load-related deterioration index are classified into a front wheel, an inner rear wheel, and an outer rear wheel. This configuration allows tires to be grouped according to load, and allows the deterioration state of the tires to be determined efficiently.

[0011] (6) As an embodiment of the present disclosure, in (5), the input data includes temperature information of the tire; The calculation unit estimates a group of tires belonging to one of the categories based on the ranking of the median temperatures of the tires over a certain period of time, and performs verification based on the distribution of temperatures of the other tires relative to the temperature of the reference tire, using one of the estimated tire groups as a reference. This arrangement allows accurate tire grouping to be performed, eg, without the user having to input individual tire positions.

[0012] (7) As an embodiment of the present disclosure, in any one of (1) to (6), The load capacity of the vehicle used in calculating the second load-related deterioration index is classified according to one or more threshold values ​​determined based on the maximum load capacity of the vehicle. With this configuration, the second load-related deterioration index can be calculated efficiently.

[0013] (8) As an embodiment of the present disclosure, in (7), the input data includes temperature information of the tire; The calculation unit calculates the second load-related deterioration index based on a distribution of temperatures of rear tires relative to a reference temperature of front tires. With this configuration, the second load-related deterioration index can be calculated accurately.

[0014] (9) As an embodiment of the present disclosure, in any one of (1) to (8), The determination unit determines whether the tire can be retreaded as the determination of the deterioration state of the tire. With this configuration, it is possible to quickly determine whether or not retreading is necessary with sufficient accuracy.

[0015] (10) As an embodiment of the present disclosure, in any one of (1) to (9), The calculation unit calculates the operating time and the number of years of use of the tire based on time information associated with information on the condition of the tire. This configuration allows the tire's operating hours and age to be calculated accurately.

[0016] (11) A program according to an embodiment of the present disclosure, For tire management devices, Obtaining input data including information regarding a tire condition detected by a detection device mounted on the vehicle; Calculating a speed-related deterioration index, which is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index, which is a deterioration index of the tire related to a load according to a mounting position of the tire, and a second load-related deterioration index, which is a deterioration index of the tire related to a load according to a load amount of the vehicle, based on the input data; determining a deterioration state of the tire based on the speed related deterioration indicator, the first load related deterioration indicator, and the second load related deterioration indicator. With this configuration, the deterioration state of the tire can be determined by simple calculation.

[0017] (12) A tire management method according to an embodiment of the present disclosure, A tire management method executed by a tire management device, comprising: The tire management device, Obtaining input data including information regarding a tire condition detected by a detection device mounted on the vehicle; Calculating a speed-related deterioration index, which is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index, which is a deterioration index of the tire related to a load corresponding to a mounting position of the tire, and a second load-related deterioration index, which is a deterioration index of the tire related to a load corresponding to a load amount of the vehicle, based on the input data; determining a deterioration state of the tire based on the speed related deterioration indicator, the first load related deterioration indicator, and the second load related deterioration indicator. With this configuration, the deterioration state of the tire can be determined by simple calculation. Effect of the Invention

[0018] According to the present disclosure, it is possible to provide a tire management device, a program, and a tire management method that can determine the deterioration state through simple calculations. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a tire management system including a tire management device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is another diagram showing an example of the configuration of the tire management system of FIG. [Diagram 3] FIG. 3 is a diagram for explaining divisions of tire mounting positions. [Figure 4] FIG. 4 is a diagram for explaining the deterioration index. [Diagram 5] FIG. 5 is a diagram illustrating grouping using the median temperature. [Figure 6A]FIG. 6A is a graph showing an image of the distribution of temperatures of other tires relative to the temperature of a reference tire for all tires. [Figure 6B] FIG. 6B is a graph showing an image of the distribution of temperatures of the other tires relative to the temperature of a reference tire for a front tire. [Figure 6C] FIG. 6C is a graph showing an image of the distribution of temperatures of the other tires relative to the temperature of a reference tire for the inside rear tire. [Figure 6D] FIG. 6D is a graph showing an image of the distribution of temperatures of the outer rear tire relative to the temperature of a reference tire. [Figure 7] FIG. 7 is a diagram for explaining the difference in temperature distribution of rear tire temperatures relative to the temperature distribution of front tire temperatures. [Figure 8] FIG. 8 is an example of a flowchart showing a process for determining whether or not a tire can be retreaded. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, a tire management device 10 (see FIG. 1), a program, and a tire management method according to an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding parts are given the same reference numerals. In the description of this embodiment, the description of the same or corresponding parts will be omitted or simplified as appropriate.

[0021] 1 and 2 are diagrams showing an example of the configuration of a tire management system. The tire management system includes a tire management device 10. Fig. 1 is a block diagram including an example of the internal configuration of the tire management device 10 and an example of the configuration of a device mounted on a vehicle 20. Fig. 2 shows the overall configuration of the tire management system.

[0022] The tire management device 10 according to the present embodiment judges the deterioration state of the tire 30 mounted on the vehicle 20. The judgment of the deterioration state of the tire 30 may be a judgment of the degree of deterioration in order to judge whether a specific work can be performed, and in the present embodiment, it will be described as a judgment of whether the tire 30 can be retreaded. As described above, retreading is a process of scraping the surface of the tread rubber of the tire 30 and attaching new rubber to reuse the tire. For example, when the damage, chemical deterioration, and mechanical deterioration of the base tire are each sufficiently small, it can be judged that retreading is possible. Here, the tire management device 10 can indicate the deterioration state of the tire 30, for example, as a numerical value (score) or a rank, using a deterioration index as described later. The tire management device 10 is not limited to only indicating the judgment result of whether retreading is possible, but may also objectively indicate the deterioration state of each tire 30 mounted on the vehicle 20 as a numerical value in order to reflect the result in the rotation of changing the mounting position of the tire 30. Here, the vehicle 20 may be, for example, a passenger car, a truck, a bus, or a construction vehicle, and is not limited to a specific type of moving body. In this embodiment, the vehicle 20 is described as being a 12-wheel or 10-wheel truck. Also, to avoid redundancy in Figures 1 and 2, only one vehicle 20 is shown, but the tire management system may be configured to include multiple vehicles 20.

[0023] The tire management device 10 includes a communication unit 11, a storage unit 12, and a control unit 13. The control unit 13 includes an acquisition unit 131, a calculation unit 132, a determination unit 133, and an output unit 134. The tire management device 10 may be, for example, a computer as a hardware configuration. The computer may be a server computer or a portable computer such as a laptop or a tablet. Details of the components of the tire management device 10 will be described later. In this embodiment, the tire management device 10 is a computer at a location where the tire 30 is retreaded. Here, the tire management device 10 may not be a single device, but may be configured of multiple devices that are arranged at multiple locations and can transmit and receive data to each other via a network 40. In other words, multiple devices connected by the network 40 may function as the tire management device 10 shown in FIG. 1 as a whole. Therefore, for example, the tire management device 10 may be configured of a single computer as a hardware configuration, or may be configured of multiple computers connected by the network 40. When the system is configured with multiple computers, the storage unit 12 may be a shared memory that can be accessed by each computer.

[0024] The tire management device 10 may constitute a tire management system together with devices (detection device 70 and on-board communication device 80) mounted on the vehicle 20 connected by a network 40. The network 40 is, for example, the Internet. The network 40 may also be configured to include, for example, a local area network (LAN) in part. Here, the tire management system may further include a terminal device 50 used by an operator who performs retreading. The terminal device 50 is, for example, a general-purpose mobile terminal such as a smartphone or a tablet terminal, but is not limited to these. The terminal device 50 may function as a display unit that displays the determination result output by the output unit 134 described later. The tire management system may also include a storage device 90 (storage device 90 on the cloud) on the network 40 as viewed from the tire management device 10 and the devices mounted on the vehicle 20. In this embodiment, the storage device 90 includes a database that stores information on the state of the tire 30 detected by the detection device 70 mounted on the vehicle 20 as time-series data after linking it to the vehicle 20 that is the detection target. When the in-vehicle communication device 80 also outputs the position information of the vehicle 20, the database also stores the position information as time-series data. In the present embodiment, the tire management device 10 acquires, as input information, information on the condition of the tire 30 and the position information of the vehicle 20 from the database via the network 40.

[0025] In this embodiment, the vehicle 20 includes a detection device 70 and an on-board communication device 80. The detection device 70 is a device or on-board system including sensors that generates information about the state of the tires 30. In this embodiment, the detection device 70 includes a tire pressure monitoring system (TPMS).

[0026] The tire pressure monitoring system monitors the pressure (internal pressure) and temperature (internal tire temperature) of a tire 30 attached to a vehicle 20. The tire pressure monitoring system may be configured to include, for example, a sensor installed inside the tire 30, a processor that calculates and outputs the pressure of the tire 30 based on a detection value of the sensor, and a memory that stores the detection value of the sensor, etc. The sensor may include a pressure sensor and a temperature sensor.

[0027] The in-vehicle communication device 80 is a device that outputs information about the state of the tire 30 detected by the detection device 70 so that the information is stored in a database. In this embodiment, the in-vehicle communication device 80 is realized by a communication function of a digital tachograph, but is not limited thereto, and may be, for example, a dedicated communication device. The in-vehicle communication device 80 may output information about the current position of the vehicle 20 to the storage device 90 or the tire management device 10. In this embodiment, the in-vehicle communication device 80 has a GPS (Global Positioning System) function and outputs GPS information including coordinates as position information of the vehicle 20. That is, in this embodiment, the in-vehicle communication device 80 outputs information about the internal pressure and temperature of the tire 30 and the position of the vehicle 20, and these pieces of information are stored in the database of the storage device 90 on the cloud. However, the in-vehicle communication device 80 does not need to output part of the information about the internal pressure and temperature of the tire 30 and the position of the vehicle 20.

[0028] The components of the tire management device 10 will be described in detail below. The communication unit 11 is configured to include one or more communication modules connected to the network 40. The communication unit 11 may include a communication module compatible with mobile communication standards such as 4G (4th Generation) and 5G (5th Generation). The communication unit 11 may include a communication module compatible with a wired or wireless LAN standard.

[0029] The storage unit 12 is one or more memories. The memory may be, for example, a semiconductor memory, a magnetic memory, an optical memory, or the like, but is not limited to these and may be any memory. The storage unit 12 is, for example, built into the tire management device 10, but may also be configured to be accessed from the outside by the tire management device 10 via any interface.

[0030] The storage unit 12 stores various data used in various calculations performed by the control unit 13. The storage unit 12 may also store results and intermediate data of various calculations performed by the control unit 13.

[0031] In this embodiment, the storage unit 12 may temporarily store various information from the database of the storage device 90 on the cloud acquired via the communication unit 11. The storage unit 12 may also store vehicle information, which is information related to the vehicle 20 (e.g., axle configuration, etc.).

[0032] The control unit 13 is one or more processors. The processor may be, for example, a general-purpose processor or a dedicated processor specialized for a specific process, but is not limited to these and may be any processor. The control unit 13 controls the overall operation of the tire management device 10.

[0033] Here, the tire management device 10 may have the following software configuration. One or more programs used to control the operation of the tire management device 10 are stored in the storage unit 12. When the program stored in the storage unit 12 is read by the processor of the control unit 13, it causes the control unit 13 to function as an acquisition unit 131, a calculation unit 132, a determination unit 133, and an output unit 134.

[0034] The acquisition unit 131 acquires input data including information about the state of the tire 30 detected by the detection device 70 mounted on the vehicle 20. The information about the state of the tire 30 includes information about the internal pressure of the tire 30 and information about the temperature of the tire 30. The input data may also include position information of the vehicle 20.

[0035] The calculation unit 132 calculates a speed-related deterioration index, a first load-related deterioration index, and a second load-related deterioration index based on the input data. The deterioration index indicates the size or presence of a factor that deteriorates the tire 30. Each deterioration index can take, for example, either two values ​​or three values. As described later, it is possible to calculate the deterioration state of the tire 30 as a score by associating the value of each deterioration index with a numerical value. At this time, since the value that each deterioration index can take is a quantized two value or three value, the score calculation of the deterioration state of the tire 30 is not complicated. Here, the deterioration index may be configured to take any of four or more values, but is preferably two values ​​or three values ​​in order to reduce the complexity of the calculation of the deterioration state. The speed-related deterioration index is a deterioration index of the tire 30 related to the speed of the vehicle 20. The first load-related deterioration index is a deterioration index of the tire 30 related to a load according to the mounting position of the tire 30. The second load-related deterioration index is a deterioration index of the tire 30 related to a load according to the load amount of the vehicle 20. The speed-related deterioration index, the first load-related deterioration index, and the second load-related deterioration index will be described later in detail.

[0036] The calculation unit 132 may also calculate a low internal pressure running deterioration index, which is a deterioration index indicating whether or not the vehicle 20 has run with the internal pressure of the tire 30 low, based on the input data. The calculation unit 132 may also calculate the operating time and years of use of the tire 30 based on time information associated with information on the state of the tire 30. In other words, the calculation unit 132 may treat the vehicle 20 as having been operating at the time when data detected by the detection device 70 exists, and the years of use of the tire 30 as the accumulated operating time. At this time, the operating time and years of use of the tire 30 can be accurately calculated. The low internal pressure running deterioration index, operating time, and years of use are used, for example, in calculating a score of the deterioration state of the tire 30 or in determining whether or not to retread.

[0037] FIG. 3 is a diagram for explaining the classification of the mounting position of the tire 30. In this embodiment, the mounting position of the tire 30 used for calculating the first load-related deterioration index is classified into the front wheel, the rear inner wheel, and the rear outer wheel. FIG. 3 shows a vehicle 20 with 12 wheels (left diagram) and 10 wheels (right diagram) as viewed from above. The tires 30 mounted at positions P1, P2, P7, and P8 are front wheel tires and are classified as front wheels. Moreover, the tires 30 mounted at positions P3 to P6 and P9 to P12 are rear wheel tires. Among the rear wheel tires, the tires 30 mounted at positions P5, P6, P11, and P12 are classified as the rear inner wheel. Moreover, among the rear wheel tires, the tires 30 mounted at positions P3, P4, P9, and P10 are classified as the rear outer wheel. In this embodiment, the mounting position of the tire 30 is not classified as an individual position, but is classified as the front wheel, the rear inner wheel, and the rear outer wheel, which have different magnitudes of loads on the tires 30. The tires 30 can be grouped according to load, and the deterioration state of the tires 30 can be determined efficiently.

[0038] FIG. 4 is a diagram for explaining the deterioration index. In this embodiment, the speed-related deterioration index indicates whether the vehicle 20 is mainly used on expressways (value: Hi) or mainly used on general roads (value: Lo). When the vehicle 20 is mainly used on expressways, the load on the tires 30 is larger than when the vehicle 20 is mainly used on general roads. In the example of FIG. 4, the vehicle 20 is changed to be mainly used on general roads after time t2, so the load on the tires 30 is smaller. The calculation unit 132 may calculate the speed-related deterioration index by distinguishing whether the road on which the vehicle 20 has traveled is an expressway or a general road based on the position information of the vehicle 20. For example, the calculation unit 132 may obtain the speed from the position information of the vehicle 20, and may determine that the vehicle 20 is traveling on an expressway when the vehicle 20 is continuously traveling at a certain speed or higher, and may determine that the vehicle 20 is traveling on a general road otherwise. For example, the calculation unit 132 may calculate the speed-related deterioration index depending on whether the time determined to be traveling on an expressway or the time determined to be traveling on a general road is longer in a certain period of time. The calculation unit 132 can accurately calculate the speed-related deterioration index by using the position information of the vehicle 20 .

[0039] In this embodiment, the first load-related deterioration index indicates which of the above groups (front wheel, inner rear wheel, outer rear wheel) the tire 30, which is the subject of the deterioration state judgment, belongs to. When the tire 30 is mounted as a front wheel, the load on the tire 30 is larger than when it is mounted as a rear wheel. This is because the front tire continues to be subjected to a high load regardless of whether the vehicle 20, which is a truck, is empty or loaded with cargo. As for the rear tire, the inner rear wheel has a higher load than the outer rear wheel. In the example of FIG. 4, rotation is performed at time t1 and time t3, and the mounting position of the tire 30 changes to the front wheel, inner rear wheel, and outer rear wheel, so that the load on the tire 30 changes to be smaller. The calculation unit 132 determines whether the mounting position of the tire 30 is the front wheel, inner rear wheel, or outer rear wheel by calculation based on the input data. The method of determination will be described later.

[0040] As described above, the second load-related deterioration index is a deterioration index of the tire 30 related to the load corresponding to the load of the vehicle 20. The load of the vehicle 20 used in calculating the second load-related deterioration index may be classified according to one or more thresholds determined based on the maximum load of the vehicle 20. In this case, the second load-related deterioration index can be calculated efficiently. In this embodiment, the second load-related deterioration index indicates whether the second load-related deterioration index exceeds a threshold (value: Hi) or is equal to or less than the threshold (value: Lo), for example, with 50% of the maximum load as the threshold. In other words, in this embodiment, the second load-related deterioration index indicates whether the vehicle 20 is loaded with cargo close to the maximum load. The calculation unit 132 determines whether the vehicle 20 is loaded with cargo close to the maximum load by calculation based on the input data. The method of determination will be described later.

[0041] As described above, the low internal pressure running deterioration index indicates whether the vehicle 20 has run with the internal pressure of the tire 30 low (for example, less than 500 kPa). If the vehicle 20 runs for, for example, one hour or more with the low internal pressure, the damage to the base tire will be significant. Therefore, it is important to accurately determine whether the vehicle 20 has run. In this embodiment, the calculation unit 132 can determine whether the low internal pressure running deterioration index is "present" or "absent" based on, for example, the internal pressure detected by the detection device 70 and the information on the position of the vehicle 20. The calculation unit 132 distinguishes between the running state and the stopped state of the vehicle 20 based on the position information. As another example, when the input data does not include the position information of the vehicle 20 but includes the temperature information of the tire 30, the calculation unit 132 may distinguish between the running state and the stopped state of the vehicle 20 by the temperature of the tire 30 rising to or above a specific value. The specific value is a value corresponding to a significant temperature rise, and is set to 10°C, for example. In this way, the calculation unit 132 can accurately distinguish between the running state and the stopped state of the vehicle 20 according to the acquired information.

[0042] In the example of Fig. 4, the speed-related deterioration index, the second load-related deterioration index, and the low internal pressure running deterioration index are described as being two values, and the first load-related deterioration index is described as being three values, but this is not limited thereto. For example, the first load-related deterioration index may indicate whether the tire 30 belongs to a front wheel or a rear wheel, that is, may be a value that can take two values. Also, for example, the second load-related deterioration index may be a value that can take three or more values ​​by setting multiple thresholds.

[0043] The following describes a method in which the calculation unit 132 determines whether the tire 30 is mounted on the front wheel, the inner rear wheel, or the outer rear wheel by calculation based on the input data. Fig. 5 is a diagram illustrating grouping using the median temperature. Figs. 6A to 6D are graphs showing an image of the distribution of temperatures of other tires 30 relative to the temperature of a reference tire 30. Fig. 6A shows all tires 30, Fig. 6B shows the front tires, Fig. 6C shows the inner rear tire, and Fig. 6D shows the outer rear tire.

[0044] The calculation unit 132 estimates the front tire group by grouping using the median temperature of the tires 30, for example, and verifies the estimated front tire group. The calculation unit 132 then estimates the rear inner tire group in a similar manner, verifies the estimated rear inner tire group, and sets the remaining tires 30 as the rear outer tire group. Here, the vehicle 20 is described as having 12 wheels, but the same method can be used to determine whether the vehicle 20 has 10 wheels. The fact that the target vehicle 20 has 12 wheels can be obtained, for example, from vehicle information stored in the storage unit 12.

[0045] FIG. 5 is a one-dimensional graph in which the median value of the internal temperature of each tire 30 is arranged from the right side in descending order. The calculation unit 132 calculates the median value for a certain period (e.g., 2 days, 3 days, one week, etc.) from the temperature data of each tire 30 obtained as input data. The calculation unit 132 ranks the tires 30 starting from the tire with the highest median temperature. It is known that the internal temperatures of the tires 30 in the same group are approximately equal to each other while the vehicle 20 is traveling. The calculation unit 132 provisionally estimates the four tires 30 with the highest median temperature as the front tire group (group G1). The calculation unit 132 may also provisionally estimate the four tires 30 with the highest median temperature among the remaining eight tires 30 as the rear inner tire group (group 2G-2). The calculation unit 132 may provisionally estimate the other four tires 30 as the rear outer tire group (group G2-1).

[0046] The calculation unit 132 uses the tire 30 with the highest median temperature among the four tires 30 in each of the three groups as a reference. That is, the calculation unit 132 determines a reference front tire, a reference inner rear tire, and a reference outer rear tire. The calculation unit 132 plots temperatures at the same time with the horizontal axis (X-axis) as the temperature of the tire 30 as the reference and the vertical axis (Y-axis) as the temperature of the other tires 30 that are not the reference (see Figs. 6A to 6D). The calculation unit 132 uses the straight line Y=X as a reference line and verifies whether there is any tire 30 in the temperature distribution within the group that has a difference in slope and intercept of a certain level or more (i.e., is significantly different). If there is no tire 30 that is significantly different, the calculation unit 132 confirms the provisionally determined group, and if there is any tire 30 that is significantly different, it replaces it with the tire 30 in the next temperature order and verifies again.

[0047] The verification will be described in detail with reference to Figs. 6A to 6D. Fig. 6A plots all tires 30 as described above, and uses a reference front tire as the reference tire 30. There are three groups with different inclinations. Fig. 6B plots the reference front tire on the horizontal axis in a provisional front tire group (group G1). The tires 30 in group G1 are distributed in a narrow range in a nearly linear manner. In the example of Fig. 6B, the calculation unit 132 confirms the provisionally determined front tire group (group G1). Fig. 6C plots the reference inner rear tire on the horizontal axis in a provisional rear inner tire group (group 2G-2). Fig. 6D plots the reference outer rear tire on the horizontal axis in a provisional rear outer tire group (group G2-1). The calculation unit 132 performs the same verification on the provisional inner rear tire group as on the front tire group. When the provisionally determined group of inner rear tires (group 2G-2) is confirmed through the verification, the determination of whether the tire 30 is mounted on the front wheel, the inner rear wheel, or the outer rear wheel is completed.

[0048] In this embodiment, the calculation unit 132 estimates a group of tires that belongs to one of the categories (front wheels, inner rear wheels, outer rear wheels) based on the ranking of the median temperatures of the tires 30 over a certain period of time. Then, the calculation unit 132 uses one of the estimated tire groups as a reference and performs verification based on the distribution of temperatures of the other tires 30 relative to the temperature of the reference tire 30. For example, the grouping of the tires 30 can be accurately performed even without the user inputting the positions of the individual tires.

[0049] The following describes a method in which the calculation unit 132 determines whether the vehicle 20 is loaded with cargo close to the maximum load based on input data by calculation. Fig. 7 is a diagram for explaining the difference in temperature distribution of the rear tire temperature relative to the front tire temperature. The calculation unit 132 calculates the second load-related deterioration index based on the distribution of the rear tire temperature relative to the reference front tire temperature.

[0050] The left diagram of FIG. 7 shows the distribution of the temperature of the rear tire with respect to the temperature of the front tire as a reference. The front tire and the reference line here are the same as those described in FIG. 6A to FIG. 6D above. The rear tire is the combination of the inner rear tire and the outer rear tire. As described above, the load of the front tire is large. The load of the rear tire is small compared to the front tire, and the load is small especially when the vehicle 20 is empty or the load is small. Therefore, when the vehicle 20 is empty or the load is small, the distribution of the temperature of the rear tire is plotted only in the area (R1) indicating a small load compared to the front tire without any plot in the area (R2) close to the reference line as shown in the lower right diagram of FIG. 7. In contrast, when the vehicle 20 is loaded with cargo close to the maximum load, the distribution of the temperature of the rear tire has plots in the area (R2) close to the reference line as shown in the upper right diagram of FIG. 7. Therefore, the calculation unit 132 can calculate the second load-related deterioration index based on the difference in the distribution of the temperature of the rear tire. By using such a determination method, the second load-related deterioration index can be calculated accurately.

[0051] The determination unit 133 determines the deterioration state of the tire 30 based on the speed-related deterioration index, the first load-related deterioration index, and the second load-related deterioration index. As described above, the value that each deterioration index can take is a quantized binary or ternary value, so that the calculation for determining the deterioration state of the tire 30 is not complicated. That is, it is possible to determine the deterioration state of the tire 30 by a simple calculation. In addition, when the calculation unit 132 calculates the low internal pressure running deterioration index, the determination unit 133 may determine the deterioration state of the tire 30 based on the speed-related deterioration index, the first load-related deterioration index, the second load-related deterioration index, and the low internal pressure running deterioration index. At this time, the deterioration state of the tire 30 can be determined taking into consideration low internal pressure running that significantly deteriorates the base tire. In the following description, the determination unit 133 determines whether the tire 30 can be retreaded as the determination of the deterioration state of the tire 30. However, the determination unit 133 is not limited to whether the tire 30 can be retreaded, and may determine, for example, an estimated life based on the deterioration state of the tire 30.

[0052] FIG. 8 is an example of a flowchart showing the process of judging whether or not a retread is possible. In judging whether or not a retread is possible, the judging unit 133 acquires the operating time, the speed-related deterioration index, the first load-related deterioration index, the second load-related deterioration index, and the low internal pressure running deterioration index from the calculating unit 132. In the example of FIG. 8, if the operating time is more than 40 hours per week, the value is Hi, and if the operating time is 40 hours or less per week, the value is Lo. In addition, in the example of FIG. 8, the speed-related deterioration index takes the value Hi if the main road is an expressway (the ratio exceeds 50%), and the value Lo if the main road is an ordinary road. In addition, in the example of FIG. 8, the first load-related deterioration index takes the value Hi if the tire 30 to be judged is mounted on the front wheel, and takes the value Lo if the tire is mounted on the rear wheel (inner rear wheel or outer rear wheel). In addition, in the example of FIG. 8, the second load-related deterioration index takes the value Hi if the load exceeds the threshold value, with 50% of the maximum load amount as a threshold, and takes the value Lo if the load amount is equal to or less than the threshold value. In the example of FIG. 8, the low internal pressure running deterioration index takes a Hi value if the internal pressure of the tire 30 being judged is less than 500 kPa and the tire has been driven for one hour or more, and takes a Lo value if this is not the case.

[0053] If there is low internal pressure running, i.e., if the low internal pressure running deterioration index is Hi (YES in step S1), the determination unit 133 determines that retreading is not possible (step S5). In other words, the damage to the base tire is large, so the determination unit 133 determines that retreading is not possible. If there is no low internal pressure running, i.e., if the low internal pressure running deterioration index is Lo (NO in step S1), the determination unit 133 proceeds to the processing of step S2.

[0054] If the chemical deterioration score is greater than Tc (YES in step S2), the determination unit 133 determines that retreading is not possible (step S5). If the chemical deterioration score is equal to or less than Tc (NO in step S2), the determination unit 133 proceeds to the process of step S3. Here, the chemical deterioration score is a numerical value of the environmentally-derived deterioration state of the tire 30, and the larger the numerical value, the more advanced the deterioration is. Tc is a reference value for chemical deterioration determination, and may be obtained by machine learning using, for example, measurement values ​​of chemical deterioration for past performance data as learning data. In the example of FIG. 8, the chemical deterioration score is composed of two element scores, and an element reference value is set for each of the element scores. If either one of the two element scores is greater than the element reference value, it is determined that retreading is not possible. The first element score is a numerical value of natural deterioration of the surface portion of the tire 30 due to ultraviolet rays based on the cumulative years of use. The determination unit 133 calculates the cumulative years of use based on the operating time. The second element score quantifies the deterioration caused by the chemical reaction accelerated by the temperature inside the tire 30. The second element score can be calculated by, for example, "ΣConv (load-related deterioration index) × operating time × fixed coefficient × years of use". Here, "ΣConv (load-related deterioration index)" means that Hi and Lo are converted into numerical values ​​for each of the first load-related deterioration index and the second load-related deterioration index, and are calculated as an integrated value up to the present. The conversion into numerical values ​​may be, for example, converting "Hi" to "3" and "Lo" to "1". If a third value "Mid" exists, "Mid" may be converted to "2". Here, the numerical values ​​to which "Hi" or "Lo" is converted may be the same or different between the first load-related deterioration index and the second load-related deterioration index. Furthermore, the conversion into numerical values ​​may be performed according to each pattern of the combinations (four patterns) of "Hi" and "Lo" in the first load-related deterioration index and the second load-related deterioration index. Additionally, the fixed coefficient may be determined based on past performance data regarding chemical degradation.

[0055] If the mechanical deterioration score is greater than Tm (YES in step S3), the determination unit 133 determines that retreading is not possible (step S5). If the chemical deterioration score is equal to or less than Tm (NO in step S3), the determination unit 133 determines that retreading is possible (step S4). Here, the mechanical deterioration score is a numerical value of the deterioration state due to distortion of the tire 30, and the larger the numerical value, the more advanced the deterioration. Tm is a reference value for mechanical deterioration judgment, and may be obtained by machine learning using, for example, measurement values ​​of mechanical deterioration for past performance data as learning data. In the example of FIG. 8, the mechanical score is obtained by calculating "magnitude of distortion x number of distortions" as an integrated value up to the present. Here, the "magnitude of distortion" can be the above-mentioned "Conv (load-related deterioration index)", that is, Hi and Lo converted into numerical values ​​for each of the first load-related deterioration index and the second load-related deterioration index. In addition, the "number of distortions" is calculated by "years of use x operating time x Conv (speed-related deterioration index)". "Conv (speed-related deterioration index)" is, like "Conv (load-related deterioration index)", a value obtained by converting the Hi and Lo of the speed-related deterioration index.

[0056] The determining unit 133 executes the determination process as shown in FIG. 8, thereby being able to determine promptly with sufficient accuracy whether or not retreading is possible.

[0057] The output unit 134 may output the judgment result of the judgment unit 133 (e.g., judgment as to whether or not retreading is possible) to a terminal device 50 or the like used by a worker who performs retreading. Based on the displayed judgment result, the worker may proceed with the retreading work or the disposal work of the tire 30 that is the subject of the judgment. In addition, based on the displayed judgment result, the worker may plan or execute a rotation or the like that changes the mounting position of the tire 30 that is the subject of the judgment.

[0058] As described above, the tire management device 10, the program, and the tire management method according to the present embodiment can determine the deterioration state by simple calculations using the above configuration. In particular, in places where retreading is performed, it becomes possible to quickly determine whether or not a base tire can be retreaded using the above method, mainly based on data from the TPMS.

[0059] Although the embodiments of the present disclosure have been described based on the drawings and examples, it should be noted that a person skilled in the art would easily be able to make various modifications or alterations based on the present disclosure. Therefore, it should be noted that these modifications or alterations are included in the scope of the present disclosure. For example, the functions included in each component or step can be rearranged so as not to cause logical inconsistencies, and multiple components or steps can be combined into one or divided. The embodiments of the present disclosure can also be realized as a storage medium having a program executed by a processor provided in an apparatus recorded thereon. It should be understood that these are also included in the scope of the present disclosure. Contributing to the United Nations-led Sustainable Development Goals (SDGs)

[0060] The SDGs have been proposed to realize a sustainable society. One embodiment of the present disclosure is considered to be a technology that can contribute to "No. 9 Build infrastructure for industry and technological innovation." [Explanation of symbols]

[0061] 10 Tire management device 11 Communications Department 12 Storage section 13 Control section 20 Vehicles 30 Tires 40 Network 50 Terminal Equipment 70 Detection Device 80 In-vehicle communication device 90 Storage device 131 Acquisition Department 132 Calculation section 133 Judgment section 134 Output section

Claims

1. an acquisition unit that acquires input data including information regarding a tire condition detected by a detection device mounted on the vehicle; a calculation unit that calculates, based on the input data, a speed-related deterioration index that is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index that is a deterioration index of the tire related to a load corresponding to a mounting position of the tire, and a second load-related deterioration index that is a deterioration index of the tire related to a load corresponding to a load amount of the vehicle; a determination unit that determines a deterioration state of the tire based on the speed-related deterioration index, the first load-related deterioration index, and the second load-related deterioration index.

2. The calculation unit calculates a low internal-pressure running deterioration index, which is a deterioration index indicating whether or not the vehicle has run in a state where the internal pressure of the tire is low, based on the input data; and The tire management device according to claim 1 , wherein the determination unit determines the deterioration state of the tire based on the speed-related deterioration index, the first load-related deterioration index, the second load-related deterioration index, and the low internal pressure running deterioration index.

3. 3. The tire management device of claim 2, wherein when the input data includes position information of the vehicle, the calculation unit distinguishes between a running state and a stopped state of the vehicle based on the position information, and when the input data does not include the position information of the vehicle but includes temperature information of the tire, the calculation unit distinguishes between a running state and a stopped state of the vehicle by the temperature of the tire rising to or above a specific value.

4. the input data includes location information of the vehicle; The tire management device according to claim 1 , wherein the calculation unit calculates the speed-related deterioration index by distinguishing whether a road on which the vehicle has traveled is an expressway or an ordinary road based on the position information.

5. The tire management device according to claim 1 or 2, wherein the mounting positions of the tires used in calculating the first load-related deterioration index are classified into a front wheel, an inner rear wheel, and an outer rear wheel.

6. the input data includes temperature information of the tire; 6. The tire management device according to claim 5, wherein the calculation unit estimates a tire group belonging to one of the categories based on a ranking of the median temperatures of the tires over a certain period of time, and performs verification based on a distribution of temperatures of other tires relative to a temperature of a reference tire in the estimated tire group.

7. The tire management device according to claim 1 or 2, wherein the load of the vehicle used in calculating the second load-related deterioration index is classified using one or more threshold values ​​determined based on a maximum load of the vehicle.

8. the input data includes temperature information of the tire; The tire management device according to claim 7 , wherein the calculation unit calculates the second load-related deterioration index based on a distribution of temperatures of rear tires relative to a temperature of a front tire that serves as a reference.

9. The tire management device according to claim 1 or 2, wherein the determination unit determines whether the tire can be retreaded as the determination of the deterioration state of the tire.

10. The tire management device according to claim 1 , wherein the calculation unit calculates the operating time and the number of years of use of the tire based on time information associated with the information on the condition of the tire.

11. For tire management devices, Obtaining input data including information regarding a tire condition detected by a detection device mounted on the vehicle; Calculating a speed-related deterioration index, which is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index, which is a deterioration index of the tire related to a load according to a mounting position of the tire, and a second load-related deterioration index, which is a deterioration index of the tire related to a load according to a load amount of the vehicle, based on the input data; determining a deterioration state of the tire based on the speed-related deterioration indicator, the first load-related deterioration indicator, and the second load-related deterioration indicator.

12. A tire management method executed by a tire management device, comprising: The tire management device, Obtaining input data including information regarding a tire condition detected by a detection device mounted on the vehicle; Calculating a speed-related deterioration index, which is a deterioration index of the tire related to the speed of the vehicle, a first load-related deterioration index, which is a deterioration index of the tire related to a load according to a mounting position of the tire, and a second load-related deterioration index, which is a deterioration index of the tire related to a load according to a load amount of the vehicle, based on the input data; determining a deterioration state of the tire based on the speed-related deterioration indicator, the first load-related deterioration indicator, and the second load-related deterioration indicator.

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