JP2011207398A - On-vehicle tire management device - Google Patents

Abstract

An object of the present invention is to provide an in-vehicle tire management device capable of automatically notifying the time of tire replacement.
A maximum usable time Tmax or a maximum travelable distance Kmax of the tire is acquired from a wireless tag 3 provided in the tire 2, and a cumulative value of the tire used time is longer than the maximum usable time Tmax, or When the accumulated value of the tire travel distance is longer than the maximum travelable distance Kmax, the display device 11 or the speaker 12 notifies that it is time to replace the tire.
[Selection] Figure 2

Description

  The present invention relates to a vehicle-mounted tire management device that collects information from tires mounted on a vehicle and notifies the vehicle occupant of information related to the tires.

  As a conventional tire management device, a tire includes a wireless tag that stores the ID of the tire, and a wireless tag reader included in the vehicle reads information stored in the wireless tag, and whether or not the information matches the information stored in the vehicle. Determine whether. When the information matches according to this determination, there is one that prevents the vehicle body from being determined from which the vehicle body has been removed by displaying that fact on the monitor (see Patent Document 1).

  In addition, as a conventional tire management device, the tire includes a plurality of wireless tags storing the tire ID, and the number of wireless tags that can be read by the wireless tag reader included in the vehicle is reduced when the wireless tag is damaged due to wear. Some of them automatically detect the degree of wear and the location of wear. Notification is given when the wear exceeds a predetermined level (see Patent Document 2).

JP 2006-096428 A JP 2006-160029 A

  However, in the conventional tire management device, the RFID tag reader provided in the vehicle is used to notify the tire-specific ID of the presence or absence of past wearing, or to detect and notify the degree of wear, There was a problem that it was not possible to notify about the tire replacement time.

  The present invention has been made to solve the conventional problems, and an object of the present invention is to provide an in-vehicle tire management device capable of automatically notifying a tire replacement time.

  In order to achieve the above object, the present invention provides an accumulation of tire travel distance calculated by the control unit when the cumulative value of tire use time calculated by the control unit is longer than the maximum usable time acquired by the communication unit. When the value is longer than the maximum travelable distance acquired by the communication unit, it is notified that it is time to replace the tire.

  The vehicle-mounted tire management device of the present invention obtains the maximum usable time or maximum travelable distance of the tire from the wireless tag provided in the tire, and when the cumulative value of the tire used time is longer than the maximum usable time, or Since the tire replacement time is notified when the cumulative value of the tire travel distance is longer than the maximum travelable distance, the vehicle occupant can automatically receive notification of the tire replacement time. Is.

The block diagram of the vehicle-mounted tire management apparatus in one embodiment of this invention Diagram explaining the flow Diagram explaining the flow The figure explaining the structure of the data accumulate | stored in the memory | storage part which is the principal part The figure explaining the structure of the data accumulate | stored in the memory | storage part which is the principal part

  Hereinafter, an in-vehicle tire management device according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of an in-vehicle tire management device according to an embodiment of the present invention.

  The vehicle-mounted tire management device 1 receives predetermined information from the wireless tag 3 embedded in the tire 2 and notifies the tire replacement time.

  A wireless tag 3 is embedded in the tire 2 in advance. The wireless tag 3 is a device that can read stored information wirelessly from the outside, and is, for example, an RFID (Radio Frequency IDentification) tag.

  The wireless tag 3 includes a memory and an antenna for transmitting information stored in the memory. A battery is not incorporated because it operates using radio waves from the communication unit 4 described later as an energy source.

  The wireless tag 3 stores a tire ID, a maximum travelable distance Kmax, and a maximum usable time Tmax.

  The tire ID is an ID assigned to each tire. This tire ID is unique to the tire in which the wireless tag 3 is embedded, and does not overlap with the tire ID stored in the wireless tag 3 embedded in another tire.

  The maximum travelable distance Kmax is a distance that is estimated to prevent the tire in which the wireless tag 3 is embedded from performing its function when the vehicle travels normally. Tires that exceed this distance are eligible for replacement.

  This maximum travelable distance Kmax varies depending on the type of tire. For example, in the case of a normal tire, it is about 30,000 km to 40,000 km, but in the case of a studless tire, the value is about 15,000 km to 20,000 km.

  The maximum usable time Tmax is a time when it is estimated that if the tire is used for this time or longer, the tire in which the wireless tag 3 is embedded cannot perform its function when the vehicle travels normally. If this time is exceeded, the rubber is deteriorated and is subject to replacement.

  Whether or not a tire can be used is determined not by the time that the tire is used for traveling, but by whether or not the cumulative total of the time when the tire is mounted on the vehicle exceeds the maximum usable time Tmax, regardless of whether the tire is used for traveling. The

  The maximum usable time Tmax varies depending on the type of tire. For example, a normal tire has a value of about 5 years, but a studless tire has a value of about 3 years.

Hereinafter, the configuration of the vehicle-mounted tire management device 1 will be described in detail. The in-vehicle tire management device 1 includes a communication unit 4 that receives various information from the wireless tag 3 and a control unit 5 that calculates a tire replacement time based on the various information acquired by the communication unit 4. When the control unit 5 determines that it is time to replace the tire, it notifies the tire replacement time from the display device 11 or the speaker 12 (the display device 11 or the speaker 12 corresponds to a notification unit). Details will be described below.

  The communication unit 4 wirelessly reads the tire ID, the maximum travelable distance Kmax, and the maximum usable time Tmax from the wireless tag 3 in which the tire 2 is embedded, and outputs the tire ID, the maximum usable time Tmax to the control unit 5.

  A plurality of tires 2 are usually mounted on the vehicle. For example, four tires 2 are mounted on the right front, left front, right rear, and left rear of the vehicle. When the communication unit 4 reads out from the wireless tag 3 of the tire 2, the control unit 5 also includes information (hereinafter referred to as “tire position information”) on which position of the vehicle the wireless tag 3 has been read out. Can be output.

  The storage unit 5 stores various information. Here, the various information is the cumulative travel distance Ksum1 and the cumulative usage time Tsum1. These pieces of information are hereinafter referred to as “tire information”.

  The cumulative travel distance Ksum1 and the cumulative usage time Tsum1 are both stored separately for each tire ID. By doing so, it is possible to accurately notify the replacement time for each tire.

  The cumulative travel distance Ksum1 is a cumulative value of the distance traveled with the tire 2 mounted on the vehicle. The accumulated use time Tsum1 is a cumulative value of the time when the tire 2 is mounted on the vehicle. The storage unit 6 is configured by a storage medium such as a hard disk or a flash memory, for example.

  The speed sensor 7 detects the traveling speed of the vehicle. For example, the speed sensor 7 detects the traveling speed based on a vehicle speed pulse that represents the rotational speed of the wheel. The traveling speed detected by the speed sensor 7 is output to the control unit 5.

  The gyro 8 is a gyro sensor that calculates and outputs a yaw rate (hereinafter referred to as a “yaw rate value”) that is an angular velocity of rotation about the vertical direction of the vehicle. The yaw rate value calculated by the gyro 8 is output to the control unit 5. It is possible to calculate a relative azimuth change amount in the traveling direction of the own vehicle from the yaw rate value. By combining with a GPS receiver, a geomagnetic sensor, etc., the absolute direction of the vehicle can be calculated.

  The GPS receiver 9 receives radio waves from a plurality of GPS satellites and demodulates the received signals to measure the absolute position of the receiver. The absolute position measured by the GPS receiver 9 is output to the control unit 5.

  The acceleration sensor 10 detects at least the acceleration of the longitudinal detection axis and outputs the result (hereinafter referred to as “acceleration information”). The acceleration information is output to the control unit 5. The acceleration sensor 10 may be mounted with a sensor capable of detecting the acceleration of the left-right direction detection axis and the acceleration of the vertical direction detection axis.

  The display device 11 includes a display device such as a liquid crystal display. The speaker 12 notifies the vehicle occupant by voice. When the control unit 5 determines that it is time to replace the tire, it notifies the display device 11 or the speaker 12 that it is time to replace the tire.

The external output device 13 reads out data from the inserted external storage medium 14 or writes data into the external storage medium 14 and is controlled by the control unit 5. The external storage medium 14 is a non-volatile memory such as an SD card or a USB memory, for example.

  The controller 5 includes, for example, a CPU, a ROM (Read Only Memory) that stores a program for controlling the CPU, and a RAM (Random Access Memory) that temporarily stores data. The CPU reads and executes a program stored in the ROM. The control unit 5 calculates a tire replacement time based on various information acquired by the communication unit 4, and the operation will be described in detail below.

  About the vehicle-mounted tire management apparatus 1 comprised as mentioned above, the operation | movement is demonstrated using FIG. 2, FIG. FIG. 4 is a flowchart of the vehicle-mounted tire management device according to the embodiment of the present invention.

  The control unit 5 starts processing when the ignition key is turned on. When the process starts, the control unit 5 reads the tire ID, the maximum travelable distance Kmax, and the maximum usable time Tmax from the wireless tag 3 embedded in the tire 2 attached to the vehicle via the communication unit 4. (S01).

  Following S01, the control unit 5 checks whether or not the tire information of the tire ID that matches the tire ID acquired in S01 is stored in the storage unit 6 (S02). When the tire information of the tire ID acquired in S01 does not exist in the storage unit 6 (NO in S02), the control unit 5 secures a storage area for storing the tire information of the tire ID in the storage unit 6 (S03).

  As the tire information of the newly created tire ID, the tire ID, the maximum travelable distance Kmax, and the maximum usable time Tmax acquired from the wireless tag 3 in S01 are 0 km for the cumulative travel distance Ksum1. However, 0 hours is stored in the accumulated usage time Tsum1.

  After S03, or when tire information of a tire ID that matches the tire ID acquired in S01 is stored in the storage unit 6 (YES in S02), the control unit 5 acquires the tire acquired from the storage unit 6 in S01. Tire information corresponding to the ID is read (S04). The tire information to be read is the tire ID, the maximum travelable distance Kmax, the maximum usable time Tmax, the cumulative travel distance Ksum1, and the cumulative use time Tsum1.

  After S04, the control unit 5 calculates the travel distance of the vehicle (hereinafter referred to as “travel distance Know”) by integrating the travel speed output from the speed sensor 7, and the GPS receiver 9 calculates it. Based on the time information, the usage time of the tire 2 (hereinafter referred to as “use time Tnow”) is calculated (S05). The travel distance Know is a distance that the tire 2 is actually used for traveling the vehicle (when the vehicle speed is 0 or more). The use time Tnow is a time that has elapsed since the use of the tire 2 was started.

  Following S04, the control unit 5 performs a warning process (hereinafter referred to as “warning process”) at the tire replacement time using the tire information read in S04 and the value calculated in S05. This process will be described later.

  When the warning process (S05) ends, the control unit 5 stores the value updated in S05 in the storage unit 6 (S07).

  After S04, if the ignition key remains on (NO in S08), the control unit 5 returns the process to S04. If the ignition key is turned off (YES in S08), the control unit 5 ends the process.

  After finishing the process, the control unit 5 can return the process to the start of FIG. 2 again. When the tire is changed, the ignition key is usually turned off. By executing the processing of FIG. 2 again after the ignition key is turned on, it is possible to automatically notify the tire replacement timing accurately even when the tire 2 is replaced.

  Hereinafter, the warning process in S05 will be described in detail with reference to FIG.

  After S05, the control unit 5 obtains “cumulative travel distance Ksum2” by adding “travel distance Know calculated in S04” to “cumulative travel distance Ksum1 read in S04” (S09). This cumulative travel distance Ksum2 is the latest cumulative travel distance of the currently installed tire.

  Next to S09, the control unit 5 obtains “cumulative use time Tsum2” by adding “use time Tnow calculated in S04” to “cumulative use time Tsum1 read in S04” (S10). This cumulative usage time Tsum2 is the latest cumulative usage time of the currently mounted tire.

  After S10, the control unit 5 compares “cumulative travel distance Ksum2” with “maximum travelable distance Kmax read in S04”. When “cumulative travel distance Ksum2” is larger than “maximum travelable distance Kmax read in S04” (YES in S11), the tire currently being mounted exceeds the maximum travelable distance, so that the tire replacement is notified (S14). ). The processing of S14 is hereinafter referred to as “tire replacement notification processing”.

  On the other hand, when the “cumulative travel distance Ksum2” is equal to or less than the “maximum travelable distance Kmax read out in S04” (NO in S11), it is not necessary to notify the tire replacement for the currently installed tire regarding the maximum travelable distance. The process proceeds to S12.

  After S11, the control unit 5 compares the “cumulative usage time Tsum2” with the “maximum available time Tmax read in S04”. When the “cumulative use time Tsum2” is larger than the “maximum usable time Tmax read in S04” (YES in S12), the tire currently in use has exceeded the cumulative use time, so that the tire replacement notification process (S14). It becomes the object of.

  On the other hand, when the “cumulative use time Tsum2” is equal to or less than the “maximum usable time Tmax read in S04” (NO in S12), it is not necessary to notify the tire replacement that is currently mounted, so other notification processes ( S13) is performed.

  When S11 is NO and S12 is also NO, notification of tire replacement is unnecessary. At this time, the control part 5 performs other alerting | reporting processes (S13).

  The other notification processing is, for example, notifying the cumulative travel distance Ksum2 or the cumulative usage time Tsum2 as numerical information from the display device 11 or the speaker 12, or indicating how much longer the vehicle travels will be the tire replacement time. There is a process of giving notification from the speaker 12.

  When S11 is YES or S12 is YES, the control unit 5 performs a tire replacement notification process. When S11 is YES, the control unit 5 performs control so as to notify, for example, “the currently mounted tire exceeds the maximum travelable distance. It is time to replace”.

Further, when S12 is YES, the control unit 5 performs control so as to notify, for example, “the currently mounted tire exceeds the maximum usable time. It is time for replacement”. This notification is performed by at least one of display by the display device 11 and sound output from the speaker 12. This notification is performed so as to know which tire is to be replaced for each tire.

  When S13 or S14 ends, the control unit 5 stores the cumulative travel distance Ksum2 obtained in S09 and the cumulative use time Tsum2 obtained in S10 in the storage unit 6 as a new cumulative travel distance Ksum1 and a cumulative use time Tsum1. (S07).

  About the vehicle-mounted tire management apparatus 1 which operate | moves as mentioned above, the specific usage example is demonstrated using FIG. FIG. 4 is a diagram for explaining the structure of data stored in the storage unit 6.

  FIG. 4A shows data immediately after four tires 2 (tire IDs IDa, IDb, IDc, IDd) are attached from the initial state. Four storage areas are newly created by the process of S03 in FIG.

  (B) in FIG. 4 is data after traveling for 55,000 km over 0.5 years from the state of (a). Since the tires are not changed, the cumulative travel distance Ksum1 and the cumulative usage time Tsum1 of all tires are updated as needed by the process of S17 in FIG.

  (C) of FIG. 3 is data immediately after the tire is replaced in the state of (b) and four tires 2 are newly attached (tire IDs are IDe, IDf, IDg, IDh). Four new storage areas are created by the process of S03 in FIG. In addition, information on tires before replacement (tire IDs IDa, IDb, IDc, IDd) is also retained without being deleted.

  (D) of FIG. 3 is data after traveling 10,000 km over one year from the state of (c). The accumulated travel distance Ksum1 and the accumulated usage time Tsum1 of the tires (tire IDs IDa, IDb, IDc, IDd) that are mounted are updated by the process of S17 of FIG. In addition, the accumulated use time Tsum1 of the tires A, B, C, and D before replacement is updated by the process of S07 in FIG. 2 as well as the tires E, F, G, and H that are mounted.

  As described above, the vehicle-mounted tire management device according to the embodiment of the present invention acquires the maximum usable time Tmax or the maximum travelable distance Kmax of the tire from the wireless tag 3 provided in the tire 2, and uses the tire. When the cumulative value of time is longer than the maximum usable time Tmax, or when the cumulative value of travel distance of the tire is longer than the maximum travelable distance Kmax, it is notified that it is time to replace the tire. As a result, the vehicle occupant can automatically receive notification of the tire replacement time.

  Although the wireless tag 3 in one embodiment of the present invention has been described as not including a battery, it may be a small wireless device including a battery.

  In addition, the vehicle on which the vehicle-mounted tire management device according to one embodiment of the present invention is mounted may be a vehicle that obtains propulsive force by wheels. For example, the vehicle may be not only a normal passenger car but also a large vehicle such as a bus or a truck, or may be a motorcycle or a bicycle.

  In the present embodiment, it is described that the control unit 5 calculates the travel distance of the vehicle by integrating the travel speed output from the speed sensor 7 in S05. However, the movement of the current position calculated by the GPS receiver 9 is described. The travel distance may be calculated based on the history.

  Note that the in-vehicle tire management device according to the embodiment of the present invention stores the cumulative travel distance Ksum1 and the cumulative usage time Tsum1 separately for each tire ID in the storage unit 6, and the control unit 5 is currently installed. The cumulative travel distance Ksum1 and the cumulative usage time Tsum1 corresponding to the tire ID being read are read out from the storage unit 6.

  In this way, for example, even when the owner of the vehicle uses a plurality of types of tires properly, such as when a studless tire is mounted on the vehicle in the winter and replaced with a normal tire in the summer, There is an effect that the occupant can automatically receive notification of the tire replacement time.

  The control unit 5 can store the tire position information in association with each other when storing the cumulative travel distance Ksum1 and the cumulative usage time Tsum1 in the storage unit 6. For example, the tire position information corresponds to the “current mounting position” in FIG. Further, the cumulative travel distance Ksum1 is stored separately for the front wheels and the rear wheels.

  For example, the control unit 5 determines that the rotation needs to be performed when the difference between the cumulative travel distance as the front wheels and the cumulative travel distance as the rear wheels exceeds a certain threshold value (for example, 55,000 km). . With such a data structure, the control unit 5 can notify not only tire replacement notification but also tire rotation execution when performing the notification process in S13 of FIG.

  The control unit 5 can correct the maximum travelable distance Kmax in consideration of the acceleration information detected by the acceleration sensor 10. Specifically, when acceleration (sudden acceleration, sudden deceleration) of a predetermined value or more is performed a predetermined number of times or more, deterioration of the tire 2 is accelerated as compared with normal traveling. Therefore, the maximum travelable distance Kmax is shortened.

  Therefore, the control unit 5 can use a value obtained by subtracting a value obtained based on the acceleration information from the maximum travelable distance Kmax as the maximum travelable distance. By doing in this way, there exists an effect that the passenger | crew of a vehicle can receive the notification of the replacement | exchange time of the tire in which deterioration of the tire 2 accelerated.

  The controller 5 can correct the maximum travelable distance Kmax in consideration of the yaw rate value calculated by the gyro 8. A left or right turn of the vehicle can be detected by the fluctuation of the yaw rate value. When the number of right / left turns of the vehicle increases, the deterioration of the tire 2 is accelerated as compared with normal traveling. Therefore, the maximum travelable distance Kmax is shortened.

  Therefore, the control unit 5 can use a value obtained by subtracting a value obtained based on the yaw rate value from the maximum travelable distance Kmax as the maximum travelable distance. By doing in this way, there exists an effect that the passenger | crew of a vehicle can receive the notification of the replacement | exchange time of the tire in which deterioration of the tire 2 accelerated.

  The control unit 5 collects at least one of the cumulative travel distance Ksum1, the cumulative use time Tsum1, the maximum travelable distance Kmax, or the maximum useable time Tmax stored in the storage unit 6 for each tire ID, Recording can be performed on the external storage medium 14 via the output device 13.

  By doing in this way, there exists an effect that the owner of a vehicle can manage the information regarding replacement | exchange of a tire with personal PC etc. FIG.

  INDUSTRIAL APPLICABILITY The present invention is useful as an in-vehicle tire management device that collects information from tires mounted on a vehicle and notifies the vehicle occupant of information related to the tires.

DESCRIPTION OF SYMBOLS 1 In-vehicle tire management apparatus 2 Tire 3 Wireless tag 4 Communication part 5 Control part 6 Storage part 7 Speed sensor 8 Gyro 9 GPS receiver 10 Acceleration sensor 11 Display apparatus 12 Speaker 13 External output apparatus 14 External storage medium

Claims (5)

A communication unit that wirelessly obtains the maximum usable time or maximum travelable distance of the tire from a wireless tag provided on the tire;
A control unit for calculating a cumulative value of the usage time or a cumulative value of the mileage of the tire currently mounted on the vehicle;
A notification unit that notifies the tire replacement time,
When the cumulative value of the tire usage time calculated by the control unit is longer than the maximum usable time acquired by the communication unit, or the cumulative value of the tire travel distance calculated by the control unit is the notification unit. A vehicle-mounted tire management device that notifies that it is time to replace a tire when it is longer than the maximum travelable distance acquired by the communication unit. The communication unit further acquires a tire ID assigned to each tire from a wireless tag provided on the tire,
The in-vehicle tire management device according to claim 1, wherein the control unit calculates a cumulative value of use time or a cumulative value of travel distance for each tire ID acquired by the communication unit. The communication unit, when acquiring the maximum usable time of the tire or the maximum travelable distance wirelessly from a wireless tag provided on the tire, also acquires tire position information,
The control unit calculates a cumulative value of usage time or a cumulative value of travel distance for each tire position information acquired by the communication unit,
The in-vehicle tire management device according to claim 1, wherein the notification unit notifies the rotation of the tire based on a cumulative value of usage time or a cumulative value of travel distance calculated by the control unit. An acceleration sensor for detecting the acceleration of the vehicle;
2. The tire control unit according to claim 1, wherein the control unit calculates a tire replacement time using a value obtained by subtracting a value obtained based on an acceleration detected by the acceleration sensor from a maximum travelable distance acquired by the communication unit. The vehicle-mounted tire management device described. A gyro for calculating a yaw rate that is an angular velocity of rotation about the vertical direction of the vehicle;
2. The tire replacement time is calculated using a value obtained by subtracting a value obtained based on a yaw rate calculated by the gyro from the maximum travelable distance acquired by the communication unit. In-vehicle tire management system.