TIRE CONDITION DETERMINATION DEVICE, TIRE CONDITION DETERMINATION METHOD, AND TIRE CONDITION DETERMINATION PROGRAM

Abstract

To provide a tire state determination device, tire state determination method and tire state determination program which can highly accurately determine a state of a tire.SOLUTION: A tire state determination device 10 comprises: an acquisition unit 11A which acquires a tire state parameter being a parameter indicating a state of a tire in a case where a vehicle attached with the tire being the target is traveling, and tire wear information being information indicating the wear state in a tread part of the tire; and a determination unit 11B which determines the state of the tire using the tire state parameter and the tire wear information acquired by the acquisition unit 11A.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a tire condition determining device, a tire condition determining method, and a tire condition determining program. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known a technique disclosed in Patent Document 1 as a tire internal pressure detection method capable of easily detecting the internal pressure of a tire.

[0003] In this tire internal pressure detection method, a group of load sensors is provided that is aligned in a row in a direction intersecting the traveling direction of the vehicle, and the tire internal pressure of the vehicle that passes the group of load sensors is detected. This tire internal pressure detection method is characterized by including a step of acquiring a time change in load and a time change in a passing area when a tire passes the group of load sensors, and a step of calculating the tire internal pressure based on the acquired time change in load and time change in the passing area. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-219355 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, values ​​indicating the condition of a tire, such as the internal pressure and applied load, are greatly influenced not only by parameters that indicate the state of the tire when a vehicle equipped with the tire is traveling, such as the above-mentioned change in load over time and passing area, but also by the wear state of the tire's tread portion.

[0006] However, the technology described in Patent Document 1 takes into consideration only the above parameters, and therefore has the problem that it cannot necessarily be said to be able to accurately determine the state of the tire's internal pressure, etc.

[0007] The present invention has been made in consideration of the above circumstances, and has an object to provide a tire condition determination device, a tire condition determination method, and a tire condition determination program that can determine the condition of tires with higher accuracy. [Means for solving the problem]

[0008] The tire condition determination device according to claim 1 includes an acquisition unit that acquires tire condition parameters, which are parameters indicating a condition of a target tire when a vehicle equipped with the target tire is traveling, and tire wear information, which is information indicating a wear condition of a tread portion of the tire, and a determination unit that determines a condition related to the tire using the tire condition parameters and the tire wear information acquired by the acquisition unit. The determination unit determines the internal pressure of the tire as the tire-related condition. .

[0009] According to the tire condition determination device of claim 1, tire condition parameters, which are parameters indicating the condition of the tire when a vehicle equipped with the tire to be managed is traveling, and tire wear information, which is information indicating the wear state of the tread of the tire, are obtained, and the obtained tire condition parameters and tire wear information are used to determine the condition of the tire, thereby making it possible to more accurately determine the tire condition compared to a case in which the wear state of the tire is not taken into consideration. The situation can be determined. Furthermore, according to the tire condition determining device of claim 1, by determining the internal pressure condition of the tire as the condition related to the tire, it is possible to determine the internal pressure condition of the tire with higher accuracy.

[0010] The tire condition determination device described in claim 2 is the tire condition determination device described in claim 1, wherein the acquisition unit further acquires identification information of the tire, and acquires the tire wear information using the acquired identification information.

[0011] According to the tire condition determination device described in claim 2, tire identification information is further obtained and tire wear information is obtained using the obtained identification information, making it possible to obtain tire wear information more easily compared to a case in which the identification information is not used.

[0012] The tire condition determination device of claim 3 is the tire condition determination device of claim 2, wherein the acquisition unit further acquires tire type information which is information indicating the type of the tire, and the determination unit determines the condition of the tire for each type of tire indicated by the tire type information acquired by the acquisition unit.

[0013] According to the tire condition determination device described in claim 3, tire type information indicating the type of tire is further acquired, and the tire condition is determined for each tire type indicated by the acquired tire type information. This makes it possible to determine the tire condition with higher accuracy compared to a case in which the tire type is not taken into consideration.

[0016] Claim 4 The tire condition determination device according to claim Any one of claims 1 to 3 The tire condition determination device described in the above, wherein the tire condition parameters are at least one of contact length, contact area, change in load over time, change in passing area over time, and passing time, each of which is obtained by a load sensor as the vehicle passes.

[0017] Claim 4 According to the tire condition determination device described in the above, the tire condition parameters are at least one of the contact length, contact area, change in load over time, change in passing area over time, and passing time, each of which is obtained by a load sensor as a vehicle passes, and the tire condition can be determined according to the applied parameter.

[0018] Claim 5 The tire condition determination device according to the present invention is 4 The tire condition determination device according to any one of claims 1 to 5, wherein the acquisition unit further acquires tire temperature information indicating a temperature of the tire, and the determination unit determines a condition related to the tire using the tire condition parameters, the tire wear information, and the tire temperature information.

[0019] Claim 5 According to the tire condition determination device described in the above, tire temperature information indicating the tire temperature is further acquired, and the tire condition is determined using tire condition parameters, tire wear information, and tire temperature information, thereby making it possible to determine the tire condition with higher accuracy compared to a case in which the tire temperature is not taken into consideration.

[0020] Claim 6 The tire condition determination device according to the present invention is 5 2. The tire condition determination device according to claim 1 , wherein the acquisition unit acquires a plurality of different tire condition parameters as the tire condition parameters. The tire condition parameter acquisition unit acquires values ​​at a plurality of time periods, and the determination unit determines a condition related to the tire using the tire condition parameters at the plurality of time periods acquired by the acquisition unit.

[0021] Claim 6 According to the tire condition determination device described above, values ​​for tire condition parameters are acquired at multiple different time periods, and the tire condition is determined using the acquired tire condition parameters at the multiple time periods, making it possible to determine the tire condition over time.

[0022] Claim 7 The tire condition determination device according to the present invention is 6 In the tire condition determination device according to any one of claims 1 to 5, the determination of the condition of the tire is at least one of a determination of whether or not the condition is problematic and a determination of a value indicating the condition.

[0023] Claim 7According to the tire condition determination device described in the above, by determining the tire condition by at least one of determining whether the condition is problematic and determining the value itself indicating the condition, the tire condition can be determined more simply by determining whether the condition is problematic compared to the value itself indicating the condition. Also, the tire condition can be determined by determining the value itself indicating the condition, allowing for a wider range of applications compared to the value itself indicating the condition.

[0024] Claim 8 In the tire condition determination method described in the above, a computer acquires tire condition parameters, which are parameters indicating a state of the tire when a vehicle equipped with a target tire is running, and tire wear information, which is information indicating a wear state of a tread portion of the tire, and performs a tire condition determination process on the tire using the acquired tire condition parameters and tire wear information. of internal pressure Evaluate the situation.

[0025] Claim 8 According to the tire condition determination method described above, tire condition parameters, which are parameters that indicate the condition of the target tire when a vehicle equipped with the tire is traveling, and tire wear information, which is information that indicates the wear condition of the tread portion of the tire, are obtained, and the obtained tire condition parameters and tire wear information are used to determine the condition of the tire, thereby making it possible to determine the tire condition with higher accuracy compared to a case in which the wear condition of the tire is not taken into consideration. According to the tire condition determining method recited in claim 8, by determining the internal pressure of the tire as the condition related to the tire, the internal pressure of the tire can be determined with higher accuracy.

[0026] Claim 9 The tire condition determination program described in the above is for a computer to acquire tire condition parameters, which are parameters indicating a condition of the tire when a vehicle equipped with a target tire is running, and tire wear information, which is information indicating a wear state of a tread portion of the tire, and to determine whether the tire is in a worn state or not by using the acquired tire condition parameters and tire wear information. of internal pressure Determine the situation and execute the process.

[0027] Claim 9 According to the tire condition determination program described in the above, tire condition parameters, which are parameters that indicate the condition of the target tire when a vehicle equipped with the tire is traveling, and tire wear information, which is information that indicates the wear condition of the tread portion of the tire, are obtained, and the obtained tire condition parameters and tire wear information are used to determine the condition of the tire, thereby making it possible to determine the tire condition with higher accuracy compared to a case in which the wear condition of the tire is not taken into consideration. According to the tire condition determination program recited in claim 9, by determining the internal pressure condition of the tire as the condition related to the tire, it is possible to determine the internal pressure condition of the tire with higher accuracy. Effect of the Invention

[0028] According to the present invention, there is an effect that the tire condition can be determined with higher accuracy. [Brief description of the drawings]

[0029] [Figure 1] 1 is a block diagram showing an example of a hardware configuration of a tire condition determination system according to a first embodiment. [Diagram 2] 1 is a block diagram showing an example of a functional configuration of a tire condition determination system according to an embodiment of the present invention; [Diagram 3] FIG. 2 is a schematic configuration diagram of a measurement unit according to the embodiment. [Figure 4] FIG. 4 is a conceptual diagram of load measurement by a measurement unit according to the embodiment. [Diagram 5] 5A and 5B are diagrams illustrating detection of a load by a sensor according to an embodiment. [Figure 6] FIG. 4 is a waveform diagram showing a change over time in load measured by a sensor according to the embodiment. [Figure 7] FIG. 2 is a schematic diagram showing an example of a configuration of a tire tolerance information database according to the first embodiment. [Figure 8] FIG. 2 is a schematic diagram showing an example of a configuration of a tire wear management information database according to the embodiment. [Figure 9] 5 is a flowchart showing an example of a tire condition determination process according to the first embodiment. [Figure 10] FIG. 13 is a front view showing an example of a configuration of a tire condition warning screen according to the embodiment. [Figure 11] FIG. 13 is a front view showing an example of a configuration of a tire condition presentation screen according to the embodiment. [Figure 12] FIG. 4 is a block diagram showing an example of a hardware configuration of a tire condition determination system according to second and third embodiments. [Figure 13] FIG. 11 is a schematic diagram showing an example of a configuration of a tire tolerance information database according to the second and third embodiments. [Figure 14] FIG. 11 is a schematic diagram showing an example of the configuration of a tire condition estimation information database according to the second and third embodiments. [Figure 15] 10 is a flowchart showing an example of a tire condition determination process according to the second embodiment. [Figure 16] FIG. 13 is a front view showing an example of a configuration of a tire condition warning screen according to the second and third embodiments. [Figure 17] FIG. 13 is a front view showing an example of a configuration of a tire condition presentation screen according to the second and third embodiments. [Figure 18] 13 is a flowchart showing an example of a tire condition determination process according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In this embodiment, the present invention will be described as being applied to a tire condition determination system including a tire condition determination device, a vehicle terminal mounted on each of a plurality of vehicles on which a target tire is mounted, and a traffic management server that manages the operation of the plurality of vehicles.

[0031] [First embodiment] First, the configuration of a tire condition determination system 90A according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a block diagram showing an example of the hardware configuration of the tire condition determination system 90A according to this embodiment. Also, Figure 2 is a block diagram showing an example of the functional configuration of the tire condition determination system 90A according to this embodiment.

[0032] 1, a tire condition determination system 90A according to this embodiment includes a tire condition determination device 10, a fleet management server 30, a plurality of vehicle terminals 50, and a measurement unit 70, each of which is accessible to a network 80. Examples of the tire condition determination device 10 include information processing devices such as a personal computer and a server computer. Examples of the vehicle terminals 50 include portable terminals such as a smartphone, a tablet terminal, and a PDA (Personal Digital Assistant, mobile information terminal).

[0033] The tire condition determination device 10 according to this embodiment is a device that plays a central role in the tire condition determination system 90A. The tire condition determination device 10 includes a CPU (Central Processing Unit) 11, a memory 12 as a temporary storage area, a non-volatile storage unit 13, an input unit 14 such as a keyboard and a mouse, a display unit 15 such as a liquid crystal display, a medium reading and writing device (R / W) 16, and a communication interface (I / F) unit 18. The CPU 11, the memory 12, the storage unit 13, the input unit 14, the display unit 15, the medium reading and writing device 16, and the communication interface (I / F) unit 18 are connected to each other via a bus B. The medium reading and writing device 16 reads information written in a recording medium 17 and writes information to the recording medium 17.

[0034] The storage unit 13 is realized by an HDD (Hard Disk Drive), an SSD (Solid State Drive), a flash memory, or the like. A tire condition determination program 13A is stored in the storage unit 13 as a storage medium. The tire condition determination program 13A is stored (installed) in the storage unit 13 by setting a recording medium 17, on which the program 13A is written, in the medium reading and writing device 16, and the medium reading and writing device 16 reading the program 13A from the recording medium 17. The CPU 11 reads the tire condition determination program 13A from the storage unit 13, expands it in the memory 12, and sequentially executes the processes of the tire condition determination program 13A.

[0035] Furthermore, a tire tolerance information database 13B is stored in the storage unit 13. The tire tolerance information database 13B will be described in detail later.

[0036] On the other hand, the fleet management server 30 is a device that manages the operation of a plurality of vehicles equipped with the target tires, as described above. The fleet management server 30 includes a storage unit 33 in addition to a CPU, a memory, an input unit, a display unit, and the like similar to those of the tire condition determination device 10.

[0037] A tire wear management information database 33A is stored in the storage unit 33. The tire wear management information database 33A will be described in detail later.

[0038] Furthermore, as described above, the vehicle terminal 50 is individually installed in each of the plurality of vehicles.

[0039] Next, the functional configuration of the tire condition determining device 10 and the fleet management server 30 according to this embodiment will be described with reference to FIG.

[0040] 2, tire condition determination device 10 includes an acquisition unit 11A and a determination unit 11B. CPU 11 of tire condition determination device 10 executes tire condition determination program 13A to function as acquisition unit 11A and determination unit 11B.

[0041] The acquisition unit 11A according to the present embodiment acquires tire condition parameters, which are parameters indicating the condition of the target tire when a vehicle equipped with the tire is running, and tire wear information, which is information indicating the wear state of the tread portion of the tire. The acquisition unit 11A according to the present embodiment further acquires tire identification information, and acquires the tire wear information using the acquired identification information.

[0042] On the other hand, the determination unit 11B according to this embodiment determines the condition of the tires by using the tire condition parameters and tire wear information acquired by the acquisition unit 11A.

[0043] The acquiring unit 11A according to the present embodiment further acquires tire type information, which is information indicating the type of tire, by using the identification information. Then, the determining unit 11B according to the present embodiment determines the tire-related situation for each tire type indicated by the tire type information acquired by the acquiring unit 11A.

[0044] The determining unit 11B according to the present embodiment determines the internal pressure of the tire as the tire-related condition, but is not limited thereto. For example, the determining unit 11B may determine the load condition of the tire as the tire-related condition.

[0045] In this embodiment, the tire contact length corresponding to the measurement value obtained by the load sensor when a vehicle passes is applied as the tire condition parameter.

[0046] Here, the acquisition unit 11A according to the present embodiment further acquires tire temperature information indicating the temperature of the tire, and the judgment unit 11B according to the present embodiment judges the tire-related condition using the tire condition parameters, the tire wear information, and the tire temperature information. In addition, in the present embodiment, the judgment of the tire-related condition is applied to the condition, i.e., whether or not there is a problem with the tire internal pressure.

[0047] Meanwhile, the fleet management server 30 according to this embodiment includes a control unit 31 A. The CPU of the fleet management server 30 executes a pre-installed program to function as the control unit 31 A.

[0048] The control unit 31A according to this embodiment controls communications with the tire condition determining device 10 via the communications I / F unit 38, controls access to the storage unit 33, controls the display of various information on the display unit, and the like.

[0049] Meanwhile, FIG. 3 shows a schematic configuration diagram of the measurement unit 70 according to this embodiment. As shown in FIG. 3, the measurement unit 70 according to this embodiment includes a plurality of sensors 72 capable of detecting a load. The plurality of sensors 72 are arranged, for example, in a line at equal intervals on a straight line to form one sensor group. The interval X is set so that adjacent sensors 72 are spaced apart by a predetermined distance in the arrangement direction. Each sensor 72 has a pressure receiving surface 72A for measuring the load. For example, as shown in FIG. 3, the pressure receiving surface 72A is set to a rectangular shape, with a length in the tire passing direction set to A and a length in the sensor arrangement direction set to B. Note that the shape of the pressure receiving surface 72A is an example and is not limited thereto. The number of the plurality of sensors 72 is set so that, for example, the distance from one end side to the other end side has a length that exceeds the width W of the tire R to be measured while maintaining the interval X between adjacent sensors 72. In other words, the length of the load detection section composed of multiple sensors 72 is set by the sum of the length B of the sensors 72 in the sensor arrangement direction multiplied by the number of sensors 72 and the number of sensors 72 minus 1 multiplied by the spacing X.

[0050] 4(A) and 4(B) are conceptual diagrams of load measurement by the measuring unit 70. In FIG. 4(B), the measuring unit 70 is composed of 15 sensors 72, but this number is set for convenience of explanation and is not limited to this. Also, M in FIG. 4(B) indicates an example of the contact surface of the tire R, that is, the so-called tire footprint. As shown in FIG. 4, the measuring unit 70 is provided on the road surface z or the like so that the arrangement direction of the sensors 72 intersects with the traveling direction of the traveling vehicle. Note that the intersection means that the tire R passes across the arrangement direction of the sensors 72, and for example, the measurement accuracy is best when the tire R passes perpendicular to the arrangement direction of the sensors 72.

[0051] The measurement unit 70 measures the load as the tire R of a traveling vehicle passes over the multiple sensors 72. That is, the load is measured by scanning the contact surface M of the tire R with the multiple sensors 72. For example, in the case shown in Fig. 4(B), the measurement unit 70 measures the load with the sensors 72 from position 3 to position 13, where the tire R passes, among the multiple sensors 72.

[0052] Fig. 5 is a diagram showing detection of a load by the sensor 72. As shown in Fig. 5(A), the sensor 72 outputs a load when, for example, the leading edge Sin of the rotating tire R comes on the pressure receiving surface 72A, and as shown in Fig. 5(B), stops outputting the load when the main part of the contact surface M passes and the trailing edge Kout separates from the pressure receiving surface 72A. The load value measured by the sensor 72 is output according to the resolution Δt of the sensor 72.

[0053] Fig. 6 is a waveform diagram showing the change over time of the load measured by the sensor 72. The waveform u1 shown in Fig. 6(A) shows the change over time of the load detected by the sensor 72 at the position 3 or the position 13 in Fig. 4. Moreover, the waveform u2 shown in Fig. 6(B) shows the change over time of the load detected by the sensor 72 at the position 8 which is just on the tire center CL in the tire width direction.

[0054] As shown in Fig. 4, the contact length of the widthwise ends of the ground contact patch M is shorter than that of the tire center CL, so the time during which the tire R presses the sensor 72 at position 3 or position 8 is shorter than the time during which the tire R presses the sensor 72 at position 8. The time interval t1 of the load measurement range of the waveform u1 shown in Fig. 6(A) is shorter than the time interval t2 of the load measurement range of the waveform u2 shown in Fig. 6(B).

[0055] As described above, the measurement unit 70 outputs the load as a measurement value from the sensors 72 through which the tire R has passed, and outputs 0 (zero) as a measurement value for the load from the sensors 72 through which the tire R has not passed. The measurement values ​​measured by each sensor 72 are transmitted to the tire condition determination device 10 at the timing of measurement, using a frequency determined for each sensor 72, for example, the time resolution Δt of the sensor 72.

[0056] On the other hand, as shown in FIG. 4, the tire R according to this embodiment is provided with a transmitter 78 that wirelessly transmits information for identifying the vehicle on which the tire R is mounted, tire type information indicating the type of the tire R, and tire number information indicating the mounting position of the tire R in the vehicle.

[0057] In this embodiment, different identification information (hereinafter referred to as "vehicle identification information") is pre-assigned to each vehicle targeted by the tire condition determination system 90A as information for identifying the vehicle, and the vehicle identification information is used as information for identifying the vehicle, but it goes without saying that this is not limited to this.

[0058] In addition, in the tire condition determination system 90A according to this embodiment, the vehicle is assumed to be a truck that transports various goods, and it is assumed that tires are mounted at up to six locations on each vehicle. The tire number information is information indicating the mounting location of the tire R in the vehicle in this case, and in this embodiment, values ​​from 1 to 6 are applied in the order of left front, right front, left middle, right middle, left rear, and right rear, but it goes without saying that this is not limited to this.

[0059] Furthermore, the transmitting unit 78 according to this embodiment also has a function of detecting the temperature at the position where the transmitting unit 78 itself is installed, and wirelessly transmitting information indicating the temperature (hereinafter referred to as "tire temperature information").

[0060] In this embodiment, an RFID (Radio Frequency Identifier) ​​is applied as the transmitter 78, but this is not limited thereto, and other transmitting devices capable of medium to short-range communication such as NFC (Near Field Communication) and Bluetooth (registered trademark) may also be applied.

[0061] 3 to 5, the measurement unit 70 according to this embodiment is provided with a receiving unit 74 that receives a transmission signal from a transmitting unit 78 in the vicinity of a position where a tire R mounted on a vehicle passes when the vehicle passes over the measurement unit 70. Then, various pieces of information (hereinafter referred to as "tire-related information"), such as vehicle identification information, tire type information, tire number information, and tire temperature information, received by the receiving unit 74 from the transmitting unit 78 of the tire R are transmitted to the tire condition determination device 10 at the timing of reception.

[0062] Next, the tire tolerance information database 13B according to this embodiment will be described with reference to Fig. 7. Fig. 7 is a schematic diagram showing an example of the configuration of the tire tolerance information database 13B according to this embodiment.

[0063] The tire tolerance information database 13B according to the present embodiment is a database in which the allowable values ​​of tire condition parameters that are allowable for tires are registered. As shown in Fig. 7, the tire tolerance information database 13B according to the present embodiment stores information on tire type, wear amount, and allowable contact length.

[0064] The tire type is information indicating the type of tire, and the wear amount is information expressing the wear amount of the tire in a number of stages. In this embodiment, the state where there is absolutely no wear is set to 0 (zero)%, the maximum amount of wear expected is set to 100%, and the amount of wear is expressed in 10 stages in 10% increments, but this is not limited to this. For example, the stage of the length of the amount of wear from the state where there is absolutely no wear may be applied as a value expressing the stage of the amount of wear, and it goes without saying that the number of stages is not limited to 10 stages.

[0065] The allowable contact length is information indicating the allowable value of the contact length of the tire R of the corresponding tire type at the corresponding wear level. In this embodiment, the allowable contact length is a value obtained by an experiment using an actual machine or a computer simulation, etc., as a value indicating that the internal pressure of the tire R is equal to or lower than the allowable value when the contact length of the tire R obtained by using the measuring unit 70 exceeds the allowable value. However, this is not limited to this form, and a form in which a manager of the tire condition determination system 90A appropriately inputs a value according to the tire condition determination accuracy required for the tire condition determination system 90A, the purpose, etc. may be used.

[0066] Next, the tire wear management information database 33A according to this embodiment will be described with reference to Fig. 8. Fig. 8 is a schematic diagram showing an example of the configuration of the tire wear management information database 33A according to this embodiment.

[0067] The tire wear management information database 33A according to this embodiment is a database in which information for managing the wear status of tires mounted on a vehicle targeted by the tire condition determination system 90A is registered. As shown in Fig. 8, the tire wear management information database 33A according to this embodiment stores vehicle identification information, notification destination, tire type, and tire wear information.

[0068] The vehicle identification information is the same as the vehicle identification information described above, and the notification destination is information indicating the notification destination for the vehicle terminal 50 mounted on the corresponding vehicle. In this embodiment, an e-mail address is used as the information indicating the notification destination, but the present invention is not limited to this. For example, other information such as an IP (Internet Protocol) address may be used as the information indicating the notification destination.

[0069] The tire type is information indicating the type of tire mounted on the corresponding vehicle. As shown in Fig. 8, in this embodiment, it is assumed that only one type of tire is mounted on one vehicle, and only one type of tire is mounted on each vehicle. However, this is not limited to this embodiment, and multiple types of tires may be mounted on one vehicle.

[0070] Furthermore, the tire wear information is information indicating the amount of wear of each tire R mounted on the corresponding vehicle. In the tire wear management information database 33A according to the present embodiment, each tire R is represented by the tire number information described above, but it goes without saying that this is not limited to this.

[0071] Next, the operation of the tire condition determination system 90A according to this embodiment will be described with reference to Fig. 9 to Fig. 11. Fig. 9 is a flowchart showing an example of a tire condition determination process according to this embodiment. Fig. 10 is a front view showing an example of the configuration of a tire condition warning screen according to this embodiment. Fig. 11 is a front view showing an example of the configuration of a tire condition presentation screen according to this embodiment.

[0072] When a command to start executing a tire condition determination process is input via the input unit 14 by a user of the tire condition determination device 10 (in this embodiment, an administrator of the tire condition determination system 90A), the CPU 11 of the tire condition determination device 10 executes the tire condition determination program 13A, thereby executing the tire condition determination process shown in FIG. 9. Note that, in order to avoid confusion, a case will be described here in which the tire tolerance information database 13B and the tire wear management information database 33A have already been constructed. Also, in order to avoid confusion, a case will be described here in which a determination is made for only one tire per vehicle.

[0073] 9, the CPU 11 waits until it receives tire-related information and measurement values ​​from the measurement unit 70. Here, for the measurement values, the CPU 11 receives information on the period during which the tire contact length can be derived.

[0074] In step 102, the CPU 11 uses the received measurement value to derive the contact length L of the tire R. Note that the method of deriving the contact length L of the tire R using the measurement value obtained by the measurement unit 70 is also described in the above-mentioned JP 2019-219355 A, and therefore detailed description thereof will be omitted here.

[0075] In step 104, the CPU 11 uses the received tire-related information to identify a tire R to be processed (hereinafter, referred to as a "processing target tire"). In step 106, the CPU 11 reads out tire wear information corresponding to the identified processing target tire from the tire wear management information database 33A.

[0076] In step 108, the CPU 11 reads out from the tire tolerance information database 13B the permissible contact length P that corresponds to the type of the tire being processed and to the amount of wear indicated by the read tire wear information.

[0077] In step 110, CPU 11 adjusts the read allowable contact length P to an appropriate value according to the temperature of the tire being processed by reflecting the temperature indicated by the tire temperature information contained in the received tire-related information. That is, the higher the temperature of the tire, the higher the internal pressure of the tire. Therefore, in the tire condition determination process according to this embodiment, the higher the temperature indicated by the tire temperature information, the longer the allowable contact length P is set to increase the accuracy of determining the tire condition.

[0078] Then, in step 110, the CPU 11 determines whether the derived contact patch length L of the tire being processed exceeds the adjusted allowable contact patch length P, and if the determination is negative, the process proceeds to step 120, whereas if the determination is positive, the process proceeds to step 112.

[0079] In step 112, the CPU 11 identifies the notification destination by reading out the notification destination corresponding to the vehicle identification information of the received tire-related information from the tire wear management information database 33A. In step 114, the CPU 11 transmits, to the identified notification destination, notification information that is determined in advance as an indication that the internal pressure of the tire to be processed may be below the allowable value. By transmitting this notification information, a tire condition warning screen, as shown in FIG. 10 as an example, is displayed on the vehicle terminal 50 that has received the notification information. Therefore, a passenger such as the driver of the vehicle can know that there is a problem with the internal pressure of the tire mounted on the vehicle they are riding in by referring to this tire condition warning screen.

[0080] In step 116, the CPU 11 controls the display unit 15 to display a tire condition display screen having a predetermined configuration, and in step 118, the CPU 11 waits until the predetermined information is input.

[0081] As an example, as shown in Fig. 11, the tire condition presentation screen according to this embodiment displays information indicating the vehicle on which the target tire is mounted, as well as information indicating that the internal pressure of the target tire may be below the allowable value. Thus, the user of the tire condition determination device 10 can grasp this information. When the tire condition presentation screen shown in Fig. 11 is displayed by the display unit 15, the user, after grasping the displayed content, selects the end button 15C using the input unit 14. In response to this, the determination in step 118 is affirmative, and the process proceeds to step 120.

[0082] In step 120, CPU 11 determines whether a predetermined timing has arrived as the timing for ending the tire condition determination process, and if the determination is negative, the process returns to step 100, whereas if the determination is positive, the tire condition determination process ends. Note that in this embodiment, the timing applied is the timing when a command input for ending the tire condition determination process is made by the user of tire condition determination device 10 via input unit 14, but it goes without saying that the timing is not limited to this.

[0083] As described above, this embodiment includes an acquisition unit 11A that acquires tire condition parameters, which are parameters indicating the condition of the target tire when a vehicle equipped with the tire is running, and tire wear information, which is information indicating the wear state of the tread of the tire, and a determination unit 11B that determines the condition of the tire using the tire condition parameters and tire wear information acquired by the acquisition unit 11A. Therefore, the tire condition can be determined with higher accuracy than when the wear state of the tire is not taken into consideration.

[0084] Furthermore, according to this embodiment, tire identification information (vehicle identification information in this embodiment) is further acquired, and the acquired identification information is used to acquire tire wear information. Therefore, tire wear information can be acquired more easily compared to a case where the identification information is not used.

[0085] In addition, according to the present embodiment, tire type information, which is information indicating the type of tire, is further acquired, and the tire status is determined for each tire type indicated by the acquired tire type information. Therefore, the tire status can be determined with higher accuracy than when the tire type is not taken into consideration.

[0086] Furthermore, according to this embodiment, the internal pressure of the tire is determined, so that the internal pressure of the tire can be determined with higher accuracy.

[0087] According to this embodiment, the tire condition parameter is the contact length obtained by the load sensor when a vehicle passes by, so that the tire condition can be determined according to the contact length of the tire.

[0088] In addition, according to the present embodiment, tire temperature information indicating the tire temperature is further acquired, and the tire status is determined using the tire condition parameters, tire wear information, and tire temperature information. Therefore, the tire status can be determined with higher accuracy than when the tire temperature is not taken into consideration.

[0089] Furthermore, according to the present embodiment, the tire condition is determined by determining whether or not the condition is problematic, which makes it easier to determine the tire condition compared to the case where the tire condition is determined based on a value that indicates the condition itself.

[0090] In this embodiment, the tire contact length is applied as the tire condition parameter, but the present invention is not limited to this. For example, in addition to the contact length, any one or a combination of the contact area, the time change in load, the time change in the passing area, and the passing time may be applied as the tire condition parameter. In this case, the tire condition can be determined according to the applied parameter.

[0091] [Second embodiment] In the first embodiment, an example of a case where a tire-related condition is judged by judging whether or not the condition is problematic has been described. In contrast, in the present embodiment, an example of a case where a tire-related condition is judged by judging a value indicating the condition itself will be described.

[0092] First, the configuration of a tire condition determination system 90B according to this embodiment will be described with reference to Fig. 12. Fig. 12 is a block diagram showing an example of the hardware configuration of a tire condition determination system 90B according to this embodiment, and the same components as those in the tire condition determination system 90A according to the first embodiment shown in Fig. 1 are given the same reference numerals as in Fig. 1, and descriptions thereof will be omitted.

[0093] 12, tire condition determination system 90B according to the present embodiment differs from tire condition determination system 90A according to the first embodiment in that tire condition determination program 13A executes different processes and in that a tire permissible information database 13C is applied instead of tire permissible information database 13B. Furthermore, tire condition determination system 90B according to the present embodiment differs from tire condition determination system 90A according to the first embodiment in that a tire condition estimation information database 13D is stored in memory unit 13 of tire condition determination device 10.

[0094] Next, the tire tolerance information database 13C according to this embodiment will be described with reference to Fig. 13. Fig. 13 is a schematic diagram showing an example of the configuration of the tire tolerance information database 13C according to this embodiment.

[0095] As shown in FIG. 13, the tire tolerance information database 13C according to the present embodiment differs from the tire tolerance information database 13B according to the first embodiment only in that the tolerance internal pressure is used instead of the tolerance contact length.

[0096] The allowable internal pressure according to this embodiment is information indicating the allowable value of the internal pressure of the tire R of the corresponding tire type at the corresponding wear amount stage. In this embodiment, the allowable internal pressure is a value obtained by an experiment using an actual machine or a computer simulation, which indicates that the internal pressure of the tire R is below the allowable value when the internal pressure derived using the measurement value obtained by the measurement unit 70 is below the allowable value. However, this is not limited to this form, and a form in which a manager of the tire condition determination system 90B appropriately inputs a value according to the tire internal pressure determination accuracy required for the tire condition determination system 90B, the purpose, etc. may be used.

[0097] Next, the tire condition estimation information database 13D according to this embodiment will be described with reference to Fig. 14. Fig. 14 is a schematic diagram showing an example of the configuration of the tire condition estimation information database 13D according to this embodiment.

[0098] The tire condition estimation information database 13D according to the present embodiment is a database in which information for estimating the condition of a tire (inner pressure in the present embodiment) is registered. As shown in Fig. 14, the tire condition estimation information database 13D according to the present embodiment stores information on tire types and estimation tables.

[0099] The tire type is the same as the tire type in the tire tolerance information database 13C. The estimation table is information indicating a lookup table in which information including predetermined tire state parameters corresponding to the corresponding tire type is used as input information, and the internal pressure of the corresponding tire corresponding to the input information is used as output information.

[0100] In this embodiment, the lookup table is a table obtained by experiments using an actual device, computer simulation, etc., which outputs the internal pressure corresponding to the input information when the input information is input.

[0101] In this embodiment, the input information is the time interval t1 or t2 (time interval t2 in this embodiment) in the graph showing the time change of the load shown in FIG. 6, the area of ​​the part surrounded by the curve and the X-axis in the graph, and the temperature indicated by the tire temperature information included in the tire-related information. Here, the time interval t1 and the area can be specified from the measurement value obtained by the measurement unit 70. Note that the input information is not limited to this form, and the input information may be any one or a combination of the contact length, contact area, time change of the load, time change of the passing area, and the passing time, each of which is obtained by the measurement unit 70 when the vehicle passes. In this case, the internal pressure of the tire can be determined according to the applied parameter.

[0102] The functional configuration of the tire condition determination device 10 and the fleet management server 30 in this embodiment is the same as that in the first embodiment, except that the determination unit 11B determines the tire condition by determining the value indicating the condition itself instead of determining whether the condition is problematic or not, and therefore will not be described here.

[0103] Next, the operation of the tire condition determination system 90B according to this embodiment will be described with reference to Fig. 15 to Fig. 17. Fig. 15 is a flowchart showing an example of a tire condition determination process according to this embodiment. Fig. 16 is a front view showing an example of the configuration of a tire condition warning screen according to this embodiment. Fig. 17 is a front view showing an example of the configuration of a tire condition presentation screen according to this embodiment.

[0104] When a command to start execution of a tire condition determination process is input via input unit 14 by a user of tire condition determination device 10, CPU 11 of tire condition determination device 10 executes tire condition determination program 13A, thereby executing the tire condition determination process shown in Fig. 15. Note that, in order to avoid confusion, a case will be described here in which tire tolerance information database 13C, tire condition estimation information database 13D, and tire wear management information database 33A have already been constructed. Also, in order to avoid confusion, a case will be described here in which determination is performed for only one tire per vehicle.

[0105] 15, the CPU 11 waits until it receives tire-related information and measurement values ​​from the measurement unit 70. Here, for the measurement values, the CPU 11 receives information on the period during which the time interval t2 can be derived.

[0106] In step 202, the CPU 11 derives the time interval t2 and the above-mentioned area. In step 204, the CPU 11 uses the received tire-related information to identify the tire R to be processed (hereinafter referred to as the "processing target tire"). In step 206, the CPU 11 reads out tire wear information corresponding to the identified processing target tire from the tire wear management information database 33A.

[0107] In step 208, the CPU 11 reads out from the tire permissible internal pressure database 13C the permissible internal pressure PI that corresponds to the type of the tire being processed and to the amount of wear indicated by the read tire wear information.

[0108] In step 210, the CPU 11 reads out an estimation table corresponding to the type of the target tire from the tire condition estimation information database 13D. Then, in step 210, the CPU 11 inputs the derived input information into the read estimation table, thereby deriving the internal pressure I of the target tire.

[0109] In step 212, the CPU 11 determines whether the derived internal pressure I of the tire being processed is less than the read allowable internal pressure PI, and if the determination is negative, the process proceeds to step 222, whereas if the determination is positive, the process proceeds to step 214.

[0110] In step 214, the CPU 11 identifies the notification destination by reading out the notification destination corresponding to the vehicle identification information of the received tire-related information from the tire wear management information database 33A. In step 216, the CPU 11 transmits, to the identified notification destination, notification information that is determined in advance as an indication that the internal pressure of the tire to be processed may be below the allowable value. By transmitting this notification information, a tire condition warning screen, as shown in FIG. 16 as an example, is displayed on the vehicle terminal 50 that has received the notification information. Therefore, a passenger such as the driver of the vehicle can know that there is a problem with the internal pressure of the tire mounted on the vehicle he or she is riding in and the estimated internal pressure of the tire by referring to this tire condition warning screen.

[0111] In step 218, the CPU 11 controls the display unit 15 to display a tire condition display screen having a predetermined configuration, and in step 220, the CPU 11 waits until the predetermined information is input.

[0112] As an example, as shown in Fig. 17, the tire condition presentation screen according to this embodiment displays information indicating the vehicle on which the target tire is mounted and the estimated internal pressure of the target tire, as well as information indicating that the internal pressure of the target tire may be below the allowable value. Thus, the user of the tire condition determination device 10 can grasp this information. When the tire condition presentation screen shown in Fig. 17 is displayed by the display unit 15, the user, after grasping the displayed content, selects the end button 15C using the input unit 14. In response to this, an affirmative judgment is made in step 220, and the process proceeds to step 222.

[0113] In step 222, CPU 11 determines whether a predetermined timing has arrived as the timing for ending the tire condition determination process, and if the determination is negative, the process returns to step 200, whereas if the determination is positive, the tire condition determination process ends. Note that in this embodiment, the timing applied is the timing when the user of tire condition determination device 10 inputs an instruction to end the tire condition determination process via input unit 14, but it goes without saying that the timing is not limited to this.

[0114] As described above, according to this embodiment, the tire internal pressure value itself is also used to determine the tire condition, which allows for a wider range of applications compared to the case where only the tire internal pressure problem is used to determine the tire condition.

[0115] [Third embodiment] In this embodiment, an example is described in which the acquisition unit 11A acquires values ​​at different times as tire condition parameters, and the judgment unit 11B judges the situation regarding the tire using the tire condition parameters at the multiple times acquired by the acquisition unit 11A.

[0116] The configuration of tire condition determination system 90B according to this embodiment is the same as that according to the second embodiment, so the operation of tire condition determination system 90B according to this embodiment will be described below with reference to Figure 18. Figure 18 is a flowchart showing an example of tire condition determination processing according to this embodiment, and steps that perform the same processing as the tire condition determination processing according to the second embodiment shown in Figure 15 are given the same step numbers as in Figure 15, and descriptions thereof will be omitted.

[0117] In step 211 , the CPU 11 stores the internal pressure I derived by the processing in step 210 in the storage unit 13 .

[0118] Thereafter, in step 221A, the CPU 11 determines whether or not the internal pressure I has already been stored in the storage unit 13. If the determination is negative, the process proceeds to step 222, whereas if the determination is positive, the process proceeds to step 221B.

[0119] In step 221B, the CPU 11 reads out the internal pressure I stored in the storage unit 13, and calculates the difference S between the read out internal pressure I and the internal pressure I derived immediately before by the process of step 210.

[0120] In step 221C, the CPU 11 determines whether or not the calculated difference S is equal to or greater than a predetermined threshold value th. If the determination is negative, the process proceeds to step 222, whereas if the determination is positive, the process proceeds to step 221D.

[0121] In step 221D, the CPU 11 executes a predetermined notification process, and then proceeds to step 222. In this embodiment, the notification process is a process of notifying the vehicle terminal 50 mounted on the corresponding vehicle of information indicating that the amount of reduction in the internal pressure of the tire to be processed is larger than expected, but is not limited to this. For example, a similar notification may be sent to the fleet management server 30 or the tire condition determination device 10.

[0122] That is, in the tire condition determination process according to this embodiment, the internal pressure I of the tire to be processed that was previously stored is compared with the current internal pressure I, and if the difference S is equal to or greater than the threshold value th, it is determined that the amount of reduction in the internal pressure of the tire to be processed has exceeded the allowable range and a warning is issued.

[0123] Therefore, by executing the tire condition determination process at intervals of a predetermined period (for example, one week) as a period for determining the amount of reduced pressure, it is possible to determine the tire condition in a more realistic manner.

[0124] As described above, according to this embodiment, values ​​of tire condition parameters at different times are acquired, and the tire condition is determined using the acquired tire condition parameters at the different times, thereby making it possible to determine the tire condition over time.

[0125] In the present embodiment, the tire internal pressure is estimated using a lookup table, but the present invention is not limited to this. For example, the tire internal pressure may be estimated using AI (Artificial Intelligence).

[0126] In addition, in each of the above embodiments, the case where the transmitting unit 78 is equipped with a temperature detection function has been described, but the present invention is not limited to this. For example, a device having a temperature detection function and a communication function may be provided separately from the transmitting unit 78.

[0127] In addition, in each of the above embodiments, the tire condition determination process is executed in the tire condition determination device 10, but the present invention is not limited to this. For example, the tire condition determination process may be executed by each vehicle terminal 50. In this case, the tire condition determination device of the present invention is included in the vehicle terminal 50.

[0128] In addition, in each of the above embodiments, the measurement unit 70 is provided at only one location, but the present invention is not limited to this. For example, the measurement unit 70 may be provided at multiple locations, and the tire condition may be determined using multiple measurement values ​​obtained by each of the measurement units 70.

[0129] In each of the above embodiments, for example, the hardware structure of the processing unit that executes each process of the acquisition unit 11A and the determination unit 11B may be any of the following various processors: As described above, the above various processors include a CPU, which is a general-purpose processor that executes software (programs) and functions as a processing unit, as well as a programmable logic device (PLD), which is a processor whose circuit configuration can be changed after manufacture such as an FPGA (Field-Programmable Gate Array), a dedicated electric circuit, which is a processor having a circuit configuration designed specifically for executing a specific process such as an ASIC (Application Specific Integrated Circuit), etc.

[0130] The processing unit may be configured with one of these various processors, or may be configured with a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, or a combination of a CPU and an FPGA).The processing unit may also be configured with a single processor.

[0131] As an example of configuring the processing unit with one processor, first, there is a form in which one processor is configured with a combination of one or more CPUs and software, as represented by computers such as client and server, and this processor functions as the processing unit. Second, there is a form in which a processor is used that realizes the functions of the entire system including the processing unit with one IC (Integrated Circuit) chip, as represented by System On Chip (SoC), etc. In this way, the processing unit is configured using one or more of the above various processors as a hardware structure.

[0132] Furthermore, more specifically, the hardware structure of these various processors can be an electric circuit that combines circuit elements such as semiconductor elements. [Explanation of symbols]

[0133] 10. Tire condition determination device 11 CPU 11A Acquisition Department 11B Derivation part 12. Memory 13 Storage section 13A Tire Condition Judgment Program 13B Tire tolerance information database 13C Tire tolerance information database 13D Tire Condition Estimation Information Database 14 Input section 15 Display 16 Media Read / Write Device 17 Recording media 18 Communication I / F section 30 Traffic management server 31A Control section 33 Storage section 33A Tire wear management information database 50 Vehicle terminal 70 Measurement section 72 Sensors 72A Pressure surface 74 Receiving section 78 Transmission Department 80 Network 90A, 90B Tire Condition Judgment System Rear tire

Claims

1. an acquisition unit that acquires tire condition parameters, which are parameters that indicate a condition of the target tire when a vehicle equipped with the target tire is running, and tire wear information, which is information that indicates a wear state of a tread portion of the tire; a determination unit that determines a state related to the tire by using the tire state parameters and the tire wear information acquired by the acquisition unit; Equipped with The determination unit determines a state of an internal pressure of the tire as the state related to the tire. Tire condition determination device.

2. The acquisition unit further acquires identification information of the tire, and acquires the tire wear information by using the acquired identification information. The tire condition determining device according to claim 1 .

3. The acquisition unit further acquires tire type information which is information indicating a type of the tire, the determination unit determines a condition related to the tire for each type of tire indicated by the tire type information acquired by the acquisition unit. The tire condition determining device according to claim 2 .

4. the tire condition parameter is at least one of a contact length, a contact area, a time change in load, a time change in a passing area, and a passing time, each of which is obtained by a load sensor as the vehicle passes through the tire; The tire condition determining device according to any one of claims 1 to 3.

5. The acquisition unit further acquires tire temperature information indicating a temperature of the tire, The determination unit determines a condition related to the tire by using the tire state parameters, the tire wear information, and the tire temperature information. The tire condition determining device according to any one of claims 1 to 4.

6. The acquisition unit acquires values ​​at different times as the tire state parameters, the determination unit determines a condition related to the tire by using the tire state parameters at the plurality of time periods acquired by the acquisition unit. The tire condition determining device according to any one of claims 1 to 5.

7. The determination of the tire condition is at least one of a determination of whether or not the condition is problematic and a determination of a value indicating the condition. The tire condition determining device according to any one of claims 1 to 6.

8. The computer A tire condition parameter is a parameter indicating a condition of the target tire when a vehicle equipped with the target tire is traveling, and tire wear information is information indicating a wear state of a tread portion of the tire. determining an internal pressure state of the tire using the acquired tire condition parameters and the tire wear information; How to determine tire condition.

9. On the computer, A tire condition parameter is a parameter indicating a condition of the target tire when a vehicle equipped with the target tire is traveling, and tire wear information is information indicating a wear state of a tread portion of the tire. determining an internal pressure state of the tire using the acquired tire condition parameters and the tire wear information; A tire condition determination program for executing processing.

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