Re-fastening notification device

Abstract

A refastening notification device (2) includes a travel distance acquisition section (231) that acquires a post-installation travel distance, which is a distance traveled by a vehicle (1) from when a wheel (12a) of a tire (12) is installed to the vehicle (1) by fastening a fastening member such as a nut or a bolt to a current time, and a notification control section (232) that provides a notification that prompts refastening of the fastening member (121) in a case where the acquired post-installation travel distance is equal to or greater than a refastening distance determined in accordance with a usage state of the fastening member (121).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a re-tightening notification device that notifies of re-tightening of a fastening member for fastening a wheel. BACKGROUND

[0002] In order to mount a wheel to a vehicle, a fastening member such as a bolt or a nut needs to be fastened with an appropriate torque. Patent Literature 1 discloses a torque wrench in which a toggle mechanism operates to maintain the torque at a certain level, thereby preventing the torque from being too large or insufficient by bringing the torque to a predetermined value.

[0003] PRIOR ART

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2013-31926 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] Since the fastening member is loosened during traveling even if the fastening member is fastened with an appropriate torque, the axial force of the fastening member decreases. If the vehicle travels in a state where the axial force of the fastening member decreases, the wheel can fall off.

[0008] The present disclosure is made in view of these aspects, and aims to prevent the wheel from falling off due to loosening of the fastening member.

[0009] MEANS FOR SOLVING THE PROBLEM

[0010] In one aspect of the present disclosure, a re-tightening notification device includes a travel distance acquisition section that acquires a distance traveled after mounting, which is a distance traveled by a vehicle from when a wheel is mounted to the vehicle by fastening a fastening member to the present time, and a notification control section that provides a notification that prompts re-tightening of the fastening member in a case where the distance traveled after mounting is equal to or greater than a re-tightening distance, the re-tightening distance being determined in accordance with a usage state of the fastening member.

[0011] The travel distance acquisition section can acquire at least one of a first cumulative travel distance of the vehicle input at the time of mounting of the wheel and a second cumulative travel distance of the vehicle detected at the time when the wheel is mounted to the vehicle as the cumulative travel distance of the vehicle at the time of mounting of the wheel.

[0012] If both the first cumulative travel distance and the second cumulative travel distance are acquired, the travel distance acquisition section can acquire the shorter one of the first cumulative travel distance and the second cumulative travel distance as the cumulative travel distance of the vehicle at the time of mounting of the wheel.

[0013] The notification control section can acquire state information indicating whether the fastening member is in an unused state in which the fastening member has not been used in the past or in a used state in which the fastening member has been used in the past, and can set the retightening distance when the state information indicates the unused state to be longer than the retightening distance when the state information indicates the used state.

[0014] The travel distance acquisition section can acquire the second cumulative travel distance if the detection device detects a change in the sensor identification information and the radio field strength of the sensor provided to the wheel.

[0015] The notification control section can provide a notification prompting retightening of the fastening member and a notification of information for identifying one or more wheels having a fastening member that needs to be retightened among the plurality of wheels.

[0016] The notification control section can control at least one of the output of the power unit of the vehicle and the upper limit speed until the notification control section acquires execution information indicating that the retightening of the wheel was performed from when the notification prompting the retightening was previously provided.

[0017] Effects of the Invention

[0018] According to the present disclosure, it is possible to prevent a wheel from falling off due to loosening of a fastening member. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic diagram for explaining an outline of a retightening notification system.

[0020] Figure 2 is a schematic diagram for explaining a configuration of a retightening notification device.

[0021] Figure 3 is a schematic diagram for explaining a change in the axial force according to the usage state of the fastening member 121.

[0022] Figure 4 is a flowchart showing an example of a processing flow executed by the retightening notification device.

[0023] REFERENCE NUMERALS

[0024] S Notification System

[0025] 1 Vehicle

[0026] 11 ECU

[0027] 12 Tire

[0028] 121 Fastening Member

[0029] 122 Sensor

[0030] 2 Retightening Notification Device

[0031] 21 communication section

[0032] 22 storage section

[0033] 23 control section

[0034] 231 travel distance acquisition section

[0035] 232 notification control section

[0036] 3 terminal DETAILED DESCRIPTION

[0037] <Outline of Re-tightening Notification System S>

[0038] Figure 1 is a diagram for explaining an outline of a re-tightening notification system S. The re-tightening notification system S is a system for providing a notification of prompting re-tightening of a tightening member 121 such as a bolt or a nut for a wheel 12a of a tire 12 mounted to a vehicle 1. The re-tightening notification system S includes the vehicle 1, a re-tightening notification device 2, and a terminal 3.

[0039] The vehicle 1 is a vehicle such as a truck or a trailer. The vehicle 1 is equipped with an electronic control unit (ECU) 11. The ECU 11 transmits a cumulative travel distance of the vehicle 1 to the re-tightening notification device 2 through wireless communication. For example, the ECU 11 transmits the latest cumulative travel distance to the re-tightening notification device 2 every time the cumulative travel distance of the vehicle 1 is updated, or transmits the cumulative travel distance to the re-tightening notification device 2 every predetermined interval. The predetermined interval is a predetermined distance or a predetermined time. The predetermined distance is, for example, 1 kilometer, and the predetermined time is, for example, 1 minute.

[0040] The tire 12 of the vehicle 1 includes the wheel 12a and a tire mounted on the wheel 12a. The wheel 12a is mounted to the vehicle 1 by tightening six tightening members 121, but the number of the tightening members 121 is not limited thereto. Each of the wheels 12a is provided with a sensor 122. The sensor 122 is, for example, a sensor that detects the air pressure of the tire. The sensor 122 transmits sensor identification information for identifying the sensor 122 itself to the ECU 11 mounted in the vehicle 1 through wireless communication together with the detected air pressure.

[0041] The ECU 11 acquires the radio field intensity of the wireless communication and the sensor identification information transmitted from the sensor 122 by the wireless communication. The ECU 11 identifies the position where the wheel 12a is installed based on the pieces of sensor identification information transmitted during the travel of the vehicle 1 and the radio field intensity of the wireless communication. Further, the ECU 11 detects that the wheel 12a has been installed to the vehicle 1 based on the change in the sensor identification information and the radio field intensity caused by the replacement of the wheel 12a installed with the new wheel 12a. In other words, the ECU 11 is a detection device that detects that the wheel 12a has been installed to the vehicle 1 by detecting the change in the sensor identification information of the sensor provided on the wheel 12a and the radio field intensity.

[0042] The ECU 11 transmits the accumulated travel distance obtained when the wheel 12a is detected to be installed to the vehicle 1 to the refastening notification device 2 as the accumulated travel distance when the wheel 12a is installed to the vehicle 1. For example, the ECU 11 associates information indicating that the wheel 12a is detected to be installed to the vehicle 1 with information indicating the accumulated travel distance when the wheel 12a is installed to the vehicle 1 with each other, and transmits these pieces of information to the refastening notification device 2.

[0043] Incidentally, even if the fastening member 121 is fastened with an appropriate torque, the fastening member 121 can be loosened, and the axial force decreases while the vehicle 1 is traveling. For example, the axial force of the fastening member 121 decreases due to initial loosening. Specifically, irregularities on the lower side of the head of the fastening member 121 or the surfaces of the fastened objects that contact each other are worn to form a gap, or the tension and compression force between the fastening member 121 and the fastened objects changes from an unbalanced unstable state to a balanced stable state. When the vehicle 1 travels in a state where the axial force decreases due to initial loosening, the wheel 12a can fall off.

[0044] Here, if the distance (measured based on the accumulated travel distance) traveled to the current time after the wheel 12a is installed to the vehicle 1 by fastening the fastening member 121 is equal to or greater than the distance required for refastening, the refastening notification device 2 provides a notification prompting refastening of the fastening member 121. For example, the refastening notification device 2 transmits a message prompting refastening of the fastening member 121 to the terminal 3, thereby providing a notification prompting refastening of the fastening member 121.

[0045] The terminal 3 is a terminal used by an administrator who manages the operation of the vehicle 1 or a driver who drives the vehicle 1. The terminal is, for example, a smartphone, a tablet, or a personal computer, but is not limited thereto. Since the user of the vehicle 1, such as the administrator or the driver who confirms the notification message, can be aware that the fastening member 121 needs to be refastened, the user can perform refastening before the fastening member is loosened enough to cause the wheel 12a to fall off. Thus, the user of the vehicle 1 can avoid the wheel 12a from falling off due to loosening of the fastening member 121. Hereinafter, the configuration of the refastening notification device 2 is specifically described.

[0046] <Configuration of Refastening Notification Device 2>

[0047] Figure 2 is a schematic view for explaining the configuration of the refastening notification device 2. The refastening notification device 2 includes a communication section 21, a storage section 22, and a control section 23. The communication section 21 is a communication module for transmitting and receiving information to and from the vehicle 1 and the terminal 3. For example, the communication section 21 transmits and receives information to and from the vehicle 1 and the terminal 3 through the Internet.

[0048] The storage section 22 includes a storage medium such as a read only memory (ROM), a random access memory (RAM), and a hard disk. The storage section 22 stores a program executed by the control section 23.

[0049] The control section 23 is a computing resource including a processor such as a central processing unit (CPU). By executing the program stored in the storage section 22, the control section 23 functions as a travel distance acquisition section 231 and a notification control section 232.

[0050] The travel distance acquisition section 231 acquires the cumulative travel distance transmitted from the ECU 11. Specifically, the travel distance acquisition section 231 acquires the cumulative travel distance transmitted from the ECU 11 during travel as the current cumulative travel distance of the vehicle 1.

[0051] Further, the travel distance acquisition section 231 acquires the cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted to the vehicle 1. For example, the travel distance acquisition section 231 acquires the first cumulative travel distance of the vehicle 1 input at the time of mounting of the wheel 12a as the cumulative travel distance at the time when the wheel 12a is mounted to the vehicle 1. Specifically, the travel distance acquisition section 231 acquires the cumulative travel distance of the vehicle 1 input to the terminal 3 by the driver or the administrator of the vehicle 1 as the first cumulative travel distance and the information indicating that the wheel 12a is mounted to the vehicle 1.

[0052] The travel distance acquisition section 231 can acquire the second cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted to the vehicle 1 as the cumulative travel distance at the time when the wheel 12a is mounted to the vehicle 1. Specifically, the travel distance acquisition section 231 acquires the cumulative travel distance transmitted from the ECU 11 as the second cumulative travel distance at the time when the wheel 12a is mounted to the vehicle 1, which is associated with the information indicating that the wheel 12a is mounted to the vehicle 1.

[0053] The travel distance acquisition section 231 acquires at least one of the first cumulative travel distance and the second cumulative travel distance as the cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted to the vehicle 1.

[0054] It should be noted that the ECU 11 detects that the wheel 12a is mounted to the vehicle 1 after the vehicle 1 starts traveling because the sensor 122 transmits the sensor identification information after the vehicle 1 starts traveling. In other words, the timing at which the ECU 11 detects that the wheel 12a is mounted to the vehicle 1 is later than the timing at which the wheel 12a is actually mounted to the vehicle 1. Therefore, the second cumulative travel distance at the time when the ECU 11 detects that the wheel 12a is mounted to the vehicle 1 is greater than the first cumulative travel distance at the time when the wheel 12a is actually mounted to the vehicle 1. Here, when both the first cumulative travel distance and the second cumulative travel distance are acquired, the travel distance acquisition section 231 acquires the shorter one of the first cumulative travel distance and the second cumulative travel distance as the cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted. Therefore, the travel distance acquisition section 231 can acquire a distance close to the cumulative travel distance at the time when the wheel 12a is actually mounted to the vehicle 1 as the cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted.

[0055] The travel distance acquisition section 231 acquires the difference between the current cumulative travel distance of the vehicle 1 and the cumulative travel distance of the vehicle 1 at the time when the wheel 12a is mounted as the distance traveled after mounting, that is, the distance that the vehicle 1 has traveled from the time when the wheel 12a is mounted to the vehicle 1 by fastening the fastening member 121 to the current timing. Specifically, the notification control section 232 acquires the difference between a) the shorter one of the first cumulative travel distance and the second cumulative travel distance and b) the current cumulative travel distance of the vehicle 1 as the distance traveled after mounting.

[0056] If the distance traveled after installation is equal to or greater than the re-tightening distance (which is determined based on the usage status of the fastening component 121), the notification control unit 232 provides a notification prompting the fastening component 121 to be re-tightened. The re-tightening distance is the distance at which the wheel 12a may detach due to a decrease in axial force; for example, the specific value of the re-tightening distance is 50 km. The notification control unit 232 sends information to the terminal 3 to display a message prompting the fastening component 121 to be re-tightened. This message is a sentence such as "After the wheel 12a was installed on the vehicle 1, the vehicle 1 has traveled beyond the re-tightening distance. The fastening component 121 of the wheel 12a needs to be re-tightened." but the message is not limited to this. The terminal 3, having received the information to display this message, causes the display unit of the terminal 3 to display the message. In this way, the user of the vehicle 1 can be informed that the fastening component 121 needs to be re-tightened.

[0057] The notification control unit 232 can send information prompting the fastener 121 to both the terminal 3 and the ECU 11 of the vehicle 1. In this case, the ECU 11 causes a display installed on the driver's seat of the vehicle 1 to show a prompting the fastener 121 to be tightened. Thus, the driver of the vehicle 1 can confirm the need to tighten the fastener 121 while driving the vehicle 1.

[0058] If it is necessary to retighten any of the fastening components 121 of the multiple wheels 12a of vehicle 1, the notification control unit 232 provides a notification prompting the retightening of the fastening component 121. For example, the notification control unit 232 provides a notification prompting the retightening, as well as a notification for identifying the wheel 12a with the fastening component 121 that needs to be retightened. Specifically, the notification control unit 232 sends the message "After installing the right front wheel, vehicle 1 has traveled more than 50 km. The right front wheel needs to be retightened," thereby providing a notification prompting the retightening of the right front wheel. Therefore, the user of vehicle 1 can know which wheel 12a has the fastening component 121 that needs to be retightened among the multiple wheels 12a of vehicle 1.

[0059] Incidentally, the degree of variation in the axial force of the fastening component 121 varies depending on the usage conditions. Figure 3 This is a schematic diagram illustrating the change in axial force depending on the usage state of the fastening component 121. The horizontal axis represents the distance R traveled after installation. The vertical axis represents the axial force of the fastening component 121. If the axial force is less than the axial force LF, the wheel 12a will detach.

[0060] The curve 71 indicates a change in the axial force in a state where the fastening member 121 is not used. The curve 72 indicates a change in the axial force in a state where the fastening member 121 is used. The axial force of the fastening member 121 in the unused state is less likely to be smaller than the axial force of the fastening member 121 in the used state. Specifically, when the distance R of travel after installation exceeds 100 km, the axial force of the fastening member 121 in the unused state is smaller than the axial force LF. On the other hand, when the distance R of travel after installation exceeds 50 km, the axial force of the fastening member 121 in the used state is smaller than the axial force LF.

[0061] Here, the notification control section 232 changes the refastening distance in accordance with the use state of the fastening member 121. In this case, the notification control section 232 acquires state information indicating whether the fastening member 121 is in the unused state (in which the fastening member 121 has not been used in the past) or in the used state (in which it has been used in the past). Specifically, the notification control section 232 acquires the state information input through the terminal 3 from the terminal 3.

[0062] The notification control section 232 sets the refastening distance when the state information indicates the unused state to be longer than the refastening distance when the state information indicates the used state. Specifically, the notification control section 232 sets the refastening distance when the fastening member 121 is in the unused state to be 100 km, and sets the refastening distance when the fastening member 121 is in the used state to be 50 km. This makes it possible to provide the notification prompting refastening in accordance with the use state of the fastening member 121.

[0063] Even if the notification control section 232 provides the notification prompting refastening, without performing refastening of the fastening member 121, the notification control section 232 can restrict the travel of the vehicle 1. For example, the notification control section 232 restricts the travel of the vehicle 1 until the notification control section 232 acquires execution information indicating that refastening has been performed, from the time when the notification prompting refastening was provided. Specifically, in a case where the notification control section 232 does not acquire the execution information input through the terminal 3 after a waiting time elapses from when the notification prompting refastening was provided, the notification control section 232 restricts the travel of the vehicle 1. The waiting time is a time taken by the distance in which the wheel 12a of the vehicle 1 can fall off. The notification control section 232 sets the waiting time to be shorter as the speed of the vehicle 1 increases. When the speed of the vehicle 1 is 60 km per hour, the specific value of the waiting time is 10 minutes.

[0064] If the execution information is acquired while the travel of the vehicle 1 is restricted, the notification control section 232 cancels the restriction. In addition, if the execution information is acquired within the time from when the notification prompting refastening was provided last time until the waiting time elapses, the notification control section 232 does not restrict the travel of the vehicle 1.

[0065] The notification control section 232 limits the running of the vehicle 1 by limiting at least one of the output of the power unit of the vehicle 1 and the upper limit speed of the vehicle 1. In a case where the speed upper limit is set, when the speed of the vehicle 1 exceeds the upper limit speed, the notification control section 232 operates the brake system of the vehicle 1 to decelerate the vehicle 1. This enables the notification control section 232 to prevent the fastening member 121 from loosening, thereby preventing the wheel 12a from falling off due to loosening of the fastening member 121. In addition, if the power unit of the vehicle 1 is not activated, the notification control section 232 can stop the vehicle 1 from running by not activating the power unit of the vehicle 1. Thus, the notification control section 232 can prevent the wheel 12a from falling off due to loosening of the fastening member 121 during the running of the vehicle 1.

[0066] <Process executed by the refastening notification device 2>

[0067] Figure 4 is a flowchart illustrating an example of a process flow executed by the refastening notification device 2. The process of the flowchart of Figure 4 is executed every time the vehicle 1 runs a predetermined distance. The predetermined distance can be appropriately determined, for example, as 1 km. It should be noted that, before the process of the flowchart of Figure 4 is executed, it is assumed that the cumulative running distance of the vehicle 1 at the time when the wheel 12a is installed to the vehicle 1 has been acquired.

[0068] The running distance acquisition section 231 acquires the distance R run after installation (step S1). Specifically, the running distance acquisition section 231 acquires, as the distance R run after installation, the difference between the current cumulative running distance acquired from the vehicle 1 and the cumulative running distance of the vehicle 1 at the time when the wheel 12a is installed to the vehicle 1.

[0069] The notification control section 232 determines whether the distance R run after installation is equal to or greater than the refastening distance (step S2). If the distance R run after installation is less than the refastening distance (NO in step S2), the notification control section 232 returns to step S1.

[0070] If the distance R run after installation is equal to or greater than the refastening distance (YES in step S2), the notification control section 232 provides a notification prompting refastening (step S3). Specifically, the notification control section 232 transmits the message “The vehicle 1 has run the refastening distance or more after the wheel 12a is installed to the vehicle 1. Refastening of the fastening member 121 of the wheel 12a is required.” to the terminal 3.

[0071] The notification control section 232 determines whether the notification control section 232 has acquired the execution information indicating that refastening is performed (step S4). Specifically, the notification control section 232 determines whether the execution information input to the terminal 3 is acquired.

[0072] If the execution information has been acquired (YES in step S4), the notification control section 232 returns to step S1. If the execution information has not been acquired (NO in step S4), the notification control section 232 determines whether the duration of the notification (i.e., the time from when the re-tightening notification is provided to the current time) exceeds the waiting time (step S5).

[0073] If the duration of the notification does not exceed the waiting time (NO in step S5), the notification control section 232 returns to step S3, and steps S3 to S5 are repeated until the notification control section 232 acquires the execution information, or until the duration of the notification exceeds the waiting time. If the duration of the notification has exceeded the waiting time (YES in step S5), the notification control section 232 restricts the travel of the vehicle 1 (step S6). Specifically, the notification control section 232 reduces the output of the power unit of the vehicle 1. In addition, the notification control section 232 can operate the brake system of the vehicle 1 to stop the vehicle 1. Thus, the notification control section 232 can prevent the vibration of the vehicle 1, thereby preventing the wheel 12a from falling off the vehicle 1.

[0074] <Modification Example>

[0075] The travel distance acquisition section 231 can acquire the difference between the cumulative travel distance of the vehicle 1 at the time of the installation of the wheel 12a and the current cumulative travel distance of the vehicle 1 as the distance traveled after the installation, but the travel distance acquisition section 231 can acquire the distance traveled after the installation by other methods. For example, the ECU 11 of the vehicle 1 transmits the distance traveled from the time when the wheel 12a is installed to the vehicle 1 to the current time as the distance traveled after the installation to the re-tightening notification device 2, and the travel distance acquisition section 231 acquires the distance traveled after the installation from the vehicle 1.

[0076] <Effects of the Re-tightening Notification Device 2>

[0077] As described above, if the distance traveled after the installation (i.e., the distance traveled by the vehicle 1 from the time when the wheel 12a is installed to the vehicle 1 to the current time) is equal to or greater than the re-tightening distance determined in accordance with the usage state of the fastening member 121, the re-tightening notification device 2 provides the notification prompting the re-tightening of the fastening member 121. Thereby, the administrator or the driver of the vehicle 1 who confirms the notification prompting the re-tightening can know that the re-tightening of the fastening member 121 is required. Thus, since the administrator or the driver can re-tighten the fastening member 121, it is possible to prevent the wheel 12a from falling off due to the loosening of the fastening member 121.

[0078] The present disclosure is explained according to exemplary embodiments. The technical scope of the present disclosure is not limited to the scope described in the above-described embodiments, and various changes and modifications can be made within the scope of the present disclosure. For example, all or a part of the device can be configured with any functionally or physically dispersed or integrated units. Furthermore, new exemplary embodiments resulting from any combination thereof are also included in the exemplary embodiments. In addition, the effects of the new exemplary embodiments resulting from the combination also have the effects of the original exemplary embodiments.

Claims

1. A refastening notification device comprising: a travel distance acquisition section that acquires a post-installation travel distance, which is a distance traveled by a vehicle from when a wheel is installed to the vehicle by fastening a fastening member to the current time; and a notification control section that provides a notification that prompts refastening of the fastening member in a case where the post-installation travel distance is equal to or greater than a refastening distance determined in accordance with a usage state of the fastening member, the notification control section functions to: acquire state information that indicates whether the fastening member is in an unused state in which the fastening member has not been used in the past or in a used state in which the fastening member has been used in the past, and set the refastening distance when the state information indicates the unused state to be longer than the refastening distance when the state information indicates the used state.

2. The refastening notification device according to claim 1, wherein the travel distance acquisition section acquires at least one of a first cumulative travel distance of the vehicle input at the time of installation of the wheel and a second cumulative travel distance of the vehicle detected when the wheel is detected to be installed on the vehicle as a cumulative travel distance of the vehicle at the time of installation of the wheel.

3. The refastening notification device according to claim 2, wherein if both the first cumulative travel distance and the second cumulative travel distance are acquired, the travel distance acquisition section acquires the shorter one of the first cumulative travel distance and the second cumulative travel distance as the cumulative travel distance of the vehicle at the time of installation of the wheel.

4. The refastening notification device according to claim 2 or 3, wherein if a sensor identification information of a sensor provided to the wheel and a change in radio field intensity are detected by a detection device, the travel distance acquisition section acquires the second cumulative travel distance.

5. The refastening notification device according to any one of claims 1 to 3, wherein the notification control section provides a notification that prompts refastening of the fastening member and a notification of information for identifying one or more wheels having a fastening member that needs to be refastened among a plurality of the wheels.

6. The refastening notification device according to any one of claims 1 to 3, wherein the notification control section controls at least one of an output of a power unit of the vehicle and an upper limit speed until the notification control section acquires execution information indicating that refastening of the wheel is performed from when a notification that prompts refastening is previously provided.

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