WO2019142870A1

WO2019142870A1 - Tire system

Info

Publication number: WO2019142870A1
Application number: PCT/JP2019/001311
Authority: WO
Inventors: 雅士森
Original assignee: 株式会社デンソー
Priority date: 2018-01-19
Filing date: 2019-01-17
Publication date: 2019-07-25

Abstract

Provided is a tire system in which a vehicle body side system (2) sends a request signal to a tire side device (1) to notify the tire side device (1) of required data. On the basis of the request signal, the tire side device (1) creates, on the basis of the request signal, data about an object included in a plurality of types of objects to be detected. The tire device (1) sends the data from a first data communication unit (14) to the vehicle body side system (2). In processing a detection signal from sensing units (11, 12), a signal processing unit (13) of the tire side device (1) can deal with a plurality of objects to be detected by switching an algorithm for processing of the detection signal on the basis of the request signal.

Description

Tire system

Cross-reference to related applications

This application is based on Japanese Patent Application No. 2018-7423 filed on January 19, 2018 and Japanese Patent Application No. 2018-118776 filed on June 22, 2018, which are incorporated herein by reference. The contents of the description are incorporated by reference.

The present disclosure relates to a tire system having a tire side device and a vehicle body side system.

Conventionally, in Patent Document 1, an acceleration sensor is provided on the back surface of the tire tread, and the acceleration sensor detects the vibration applied to the tire, and based on the detection result of the vibration determines the road surface condition on the traveling road surface of the tire. A road surface condition determination method has been proposed. In this road surface condition determination method, a feature vector is extracted from the tire's vibration waveform detected by the acceleration sensor, and the similarity between the extracted feature vector and all the support vectors stored for each type of road surface is calculated. , Determine the road surface condition. For example, the kernel function is used to calculate the degree of similarity between the extracted feature vector and all the support vectors, and the type of road surface having the highest degree of similarity, such as dry road surface, wet road surface, frozen road, snow road etc., is currently running. It is determined that the road surface condition is

Further, in addition to the road surface state as described above, detection signals corresponding to tire vibration acquired by a vibration sensor unit such as an acceleration sensor provided in the tire side device are various detection targets, specifically various items related to the tire. It can be used to detect state or physical quantity. For example, the detection signal of the vibration sensor unit can also be used when detecting the wear state of a tire or the load applied to each wheel.

JP, 2016-107833, A

As described above, although the detection signal corresponding to the tire vibration acquired by the vibration sensor unit of the tire side device can be used for detection of various detection targets, the processing performed by the tire side device according to the detection target is The detection mechanism is different, such as different. For example, depending on the detection target, the processing method of the detection signal changes, for example, the required frequency band in the detection signal changes, or various calculation methods such as calculation of feature vectors change. For this reason, the algorithm of the microcomputer (hereinafter referred to as a microcomputer) of the tire-side device is different according to the detection target.

On the other hand, if the tire side device is provided with a plurality of vibration sensor units and a plurality of microcomputers, or a microcomputer with high processing capability, even if there are a plurality of detection targets, it is possible to separately detect become.

However, if a plurality of vibration sensors and microcomputers are mounted or a large microcomputer is mounted, the weight and physical size of the tire side device will be increased, and the power consumption in the tire side device will be increased. Since the tire side device is attached to the tire, it is not preferable to increase the weight and physical size, and because it is provided at a position physically separated from the vehicle side system, reduction of power consumption in the power supply unit is required. Power consumption is not desirable. In particular, in the case where a battery is used as the power supply unit, it is not easy to replace the battery, and therefore, it is required to further reduce power consumption.

Here, as a plurality of types of detection targets used in the tire system, the road surface condition, the wear condition, and the load applied to each wheel have been described as an example. However, if the detection results of a plurality of types of detection targets related to the tire are obtained, the above-described problem may occur even if the detection targets are other types.

An object of this indication is to provide a tire system which can aim at reduction of power consumption, controlling increase of weight and physique of a tire side device.

A tire system according to one aspect of the present disclosure is a tire side device that is disposed in a tire provided in a vehicle and transmits data regarding one of a plurality of detection objects related to the tire, and a vehicle body side in the vehicle And a vehicle-body-side system that receives the data on the detection target and acquires the detection result of the detection target. The tire side device is between a sensing unit that outputs detection signals corresponding to a plurality of types of detection targets, a signal processing unit that processes the detection signals of the sensing units to create data regarding the detection targets, and a vehicle body side system And the first data communication unit for transmitting data on the detection target created by the signal processing unit to the vehicle body system, and the vehicle body system is connected to the tire device. There is a second data communication unit that performs bi-directional communication and receives data related to a detection target, and a control unit that acquires a detection result of the detection target indicated by data related to the detection target based on data related to the detection target. It is assumed that In such a configuration, the vehicle body side system outputs a request signal for requesting which one of the plurality of detection targets is necessary to the tire side device through the second data communication unit, and the tire device Based on the request signal, data relating to the detection target indicated by the request signal is created from among a plurality of types of detection targets, and the data is transmitted from the first data communication unit to the vehicle body side system.

As described above, the vehicle body side system issues a request signal to each tire side device to transmit necessary data. Therefore, when processing the detection signal of the sensing unit, switching the algorithm for processing the detection signal based on the request signal can cope with a plurality of detection targets. Therefore, it is not necessary to provide a plurality of sensing units and a plurality of microcomputers for each tire-side device or a microcomputer with high processing capability, and it is possible to suppress the increase in weight and size of the tire-side device and to consume Power can be reduced.
In addition, the parenthesized reference symbol attached to each component etc. shows an example of the correspondence of the component etc. and the specific component etc. as described in the embodiment to be described later.

It is a figure showing the block configuration in the vehicles mounting state of the tire device to which the tire side device concerning a 1st embodiment was applied. It is the block diagram which showed the detailed composition of the tire side device and the body side system. It is a cross-sectional schematic diagram of the tire in which the tire side apparatus was attached. It is an output voltage waveform figure of the vibration sensor part at the time of tire rotation. It is a figure which shows a mode that the detection signal of the vibration sensor part was divided for every time window of predetermined time width | variety T. FIG. It is a flowchart of the tire side process which a tire side apparatus performs. It is a flowchart of the vehicle body side process which the control part of a vehicle body side system performs. It is the flowchart which showed the detail of the data waiting process in the vehicle body side process. It is the flowchart which showed the detail of the mapping data transmission process which the control part of a receiver performs. It is the flowchart which showed the detail of the mapping process which a communication center performs.

Hereinafter, embodiments of the present disclosure will be described based on the drawings. In the following embodiments, parts that are the same as or equivalent to each other will be described with the same reference numerals.

First Embodiment
A tire system 100 having a road surface state determining function according to the present embodiment will be described with reference to FIGS. 1 to 10. A tire system 100 according to the present embodiment is configured to include a tire side device 1 and a vehicle body side system 2. Then, the tire system 100 detects various states or physical quantities related to the tire 3 as a plurality of types of detection targets related to the tire 3 based on vibrations applied to the contact surface of the tire 3 provided on each wheel of the vehicle. Here, the tire system 100 detects the road surface state on the traveling road surface and the worn state of the tire 3 as various states related to the tire 3, and detects the load applied to the wheel as each physical quantity. In addition, the tire system 100 carries out notification of the danger of the vehicle, vehicle motion control, etc. based on detection results of various conditions and physical quantities related to the tire 3, and transmits the road surface condition on the traveling road surface to the communication center 200. ing.

As shown in FIG. 1 and FIG. 2, the tire system 100 is configured to have a tire side device 1 provided on the wheel side and a vehicle body side system 2 including each part provided on the vehicle body side. The vehicle body side system 2 includes a receiver 21, an electronic control unit for navigation control (hereinafter referred to as navigation ECU) 22, an electronic control unit for brake control (hereinafter referred to as brake ECU) 23, an electronic for left and right driving torque control A control device (hereinafter referred to as a torque control ECU) 24, a vehicle communication device 25, a notification device 26, and the like are provided. Hereinafter, the details of each part constituting the tire side device 1 and the vehicle body side system 2 will be described.

The tire side device 1 is configured to include a vibration sensor unit 11, an air pressure detection unit 12, a control unit 13, a data communication unit 14 and a power supply unit 15 as shown in FIG. 2, for example, as shown in FIG. , And is provided on the back side of the tread 31 of the tire 3.

The vibration sensor unit 11 constitutes a vibration detection unit for detecting the vibration applied to the tire 3. For example, the vibration sensor unit 11 is configured by an acceleration sensor. In this case, for example, when the tire 3 rotates, the vibration sensor unit 11 has a direction in which the vibration sensor unit 11 contacts the circular track drawn by the tire-side device 1, that is, the magnitude of the vibration in the tire tangential direction indicated by the arrow X in FIG. An acceleration detection signal is output as a corresponding detection signal. More specifically, the vibration sensor unit 10 generates, as a detection signal, an output voltage or the like in which one of the two directions indicated by the arrow X is positive and the opposite direction is negative. For example, the vibration sensor unit 10 performs acceleration detection at a predetermined sampling cycle set to a cycle shorter than one rotation of the tire 3 and outputs it as a detection signal. Although the detection signal of the vibration sensor unit 10 is represented as an output voltage or an output current, here, a case where it is represented as an output voltage is taken as an example.

The air pressure detection unit 12 is configured to include a pressure sensor 12 a and a temperature sensor 12 b. The pressure sensor 12a outputs a detection signal indicating the tire pressure, and the temperature sensor 12b outputs a detection signal indicating the temperature in the tire. Data of tire pressure and temperature indicated by detection signals of the pressure sensor 12a and the temperature sensor 12b are used as data regarding tire pressure. In the present embodiment, data of tire air pressure and temperature indicated by detection signals of the pressure sensor 12a and the temperature sensor 12b are input to the control unit 13, and the control unit 13 calculates tire air pressure at a reference temperature. That is, since the tire air pressure indicated by the detection signal of the pressure sensor 12a corresponds to the actual measurement value of the tire air pressure, the actual measurement value of the tire air pressure is corrected based on the temperature indicated by the detection signal of the temperature sensor 12b. Tire pressure is calculated.

The control unit 13 is a part corresponding to a signal processing unit that creates data on a detection target, and is a program stored in the ROM or the like and configured by a known microcomputer including a CPU, ROM, RAM, I / O, etc. It performs various processing according to. For example, the control unit 13 switches between the activation state and the sleep state of each function provided in the control unit 13 based on the detection signal of the vibration sensor unit 11, and when activated, the power from the power supply unit 15 Activate each function based on the supply. The control unit 13 receives the detection signal of the vibration sensor unit 11, and detects, for example, the rotation of the tire 3, that is, the traveling of the vehicle based on the waveform of the detection signal exceeding a predetermined threshold, thereby detecting the traveling of the vehicle. Then, each function that has been asleep is switched to the activated state. Then, the control unit 13 uses the detection signal of the vibration sensor unit 11 as a detection signal representing the vibration data in the tire tangential direction, and processes this signal to process data on road surface data and load, and further data on wear condition. Then, the process of communicating it to the data communication unit 14 is performed. Further, the control unit 13 also performs processing for obtaining data on tire air pressure based on data transmitted from the air pressure detection unit 12 and transmitting the data to the data communication unit 14.

Specifically, the control unit 13 uses the detection signal of the vibration sensor unit 11 as a detection signal representing the vibration data in the tire tangential direction, and performs the waveform processing of the vibration waveform indicated by the detection signal, whereby the tire vibration is Extract feature quantities. In the case of the present embodiment, the feature amount of the tire G is extracted by performing signal processing on a detection signal of the acceleration of the tire 3 (hereinafter referred to as a tire G). Further, the control unit 13 transmits data including the extracted feature amount to the data communication unit 14 as road surface data which is data related to the road surface state.

The feature amount is an amount indicating the feature of the vibration applied to the tire 3 acquired by the vibration sensor unit 11 and is represented as, for example, a feature vector.

An output voltage waveform of a detection signal of the vibration sensor unit 11 at the time of tire rotation is, for example, a waveform shown in FIG. As shown in this figure, the output voltage of the vibration sensor unit 11 reaches its maximum value at the start of grounding when the portion of the tread 31 corresponding to the location of the vibration sensor unit 11 starts to be grounded as the tire 3 rotates. Take. Hereinafter, a peak value at the start of grounding where the output voltage of the vibration sensor unit 11 has a maximum value is referred to as a first peak value. Furthermore, as shown in FIG. 4, when the tire 3 is in contact with the ground, a portion of the tread 31 corresponding to the location where the vibration sensor unit 11 is in contact with the ground. Output voltage has a local minimum value. Hereinafter, the peak value at the end of grounding where the output voltage of the vibration sensor unit 11 has a minimum value is referred to as a second peak value.

The reason why the output voltage of the vibration sensor unit 11 has a peak value at the above timing is as follows. That is, when the portion of the tread 31 corresponding to the location where the vibration sensor unit 11 is in contact with the tread 31 along with the rotation of the tire 3, the portion of the tire 3 having a substantially cylindrical surface in the vicinity of the vibration sensor unit 11 is It is pressed and deformed into a planar shape. By receiving the impact at this time, the output voltage of the vibration sensor unit 11 takes a first peak value. In addition, when a portion of the tread 31 corresponding to the location where the vibration sensor unit 11 is disposed is separated from the ground contact surface as the tire 3 rotates, the tire 3 is released from pressure in the vicinity of the vibration sensor unit 11 and is planar It returns to approximately cylindrical shape from. By receiving an impact when the shape of the tire 3 returns to its original shape, the output voltage of the vibration sensor unit 11 takes a second peak value. In this way, the output voltage of the vibration sensor unit 11 takes the first and second peak values at the start of grounding and at the end of grounding, respectively. Further, since the direction of the impact when the tire 3 is pressed and the direction of the impact when released from the pressing are opposite, the sign of the output voltage is also the opposite.

Here, the moment when a portion of the tire tread 31 corresponding to the location where the vibration sensor unit 11 is placed contacts the road surface is referred to as a "step-in area", and the moment leaving the road surface is referred to as a "kick-out area". The “step-in area” includes the timing at which the first peak value is obtained, and the “kick-out area” includes the timing at which the second peak value is obtained. In addition, the area in front of the stepping area is the area before the stepping area, and the area from the stepping area to the kicking area, that is, the portion of the tire tread 31 corresponding to the location where the vibration sensor unit 11 is in contact "Region after kicking out" is taken as "area after kicking out". As described above, it is possible to divide the period in which the portion of the tire tread 31 corresponding to the location where the vibration sensor unit 11 is in contact with the ground and the region before and after that period. In FIG. 4, five areas R1 to R5 are “pre-step-in area”, “step-in area”, “kick-out front area”, “kick-out area”, and “post-kick out area” in the detection signal in this order. It is shown as.

According to the road surface condition, the vibration generated in the tire 3 fluctuates in each of the divided areas, and the detection signal of the vibration sensor unit 11 changes, so that the frequency analysis of the detection signal of the vibration sensor unit 11 in each area is performed. , Detects the road surface condition on the traveling road surface of the vehicle. For example, in a slippery road surface condition such as a snowy road, the shearing force at the time of kicking is reduced, so the band value selected from the 1 kHz to 4 kHz band becomes smaller in the kicking out region R4 and the after kicking out region R5. As described above, since each frequency component of the detection signal of the vibration sensor unit 11 changes according to the road surface state, it is possible to determine the road surface state based on the frequency analysis of the detection signal.

For this reason, the control unit 13 generates a plurality of detection signals of the vibration sensor unit 11 corresponding to one rotation of the tire 3 having a continuous time axis waveform, for each time window of a predetermined time width T as shown in FIG. The feature quantity is extracted by dividing into sections and performing frequency analysis in each section. Specifically, the power spectrum value in each frequency band, that is, the vibration level in the specific frequency band is determined by performing frequency analysis in each section, and this power spectrum value is used as the feature amount.

Further, the control unit 13 extracts the ground contact section of the vibration sensor unit 11 at the time of rotation of the tire 3 based on the time change of the output voltage of the vibration sensor unit 11. The term “contacting section” as used herein means a section in which a portion of the tread 31 of the tire 3 corresponding to the location where the vibration sensor unit 11 is disposed is in contact with the road surface. In the case of the present embodiment, since the location where the vibration sensor unit 11 is disposed is the location where the tire side device 1 is disposed, a portion of the tread 31 of the tire 3 corresponding to the location where the tire side device 1 is disposed is the ground contact section. It agrees with the section where the road surface is grounded. In addition, since the tire 3 is in the ground contact zone once every one rotation, the number of rotations of the tire 3 per unit time, that is, the rotational speed can be calculated from the time interval of the ground contact zone.

Based on these, the control unit 13 transmits to the data communication unit 14 data on the extracted ground contact section and data on the rotational speed of the tire 3 as data on the load and data on the wear state.

Furthermore, the control unit 13 converts the tire air pressure under the reference temperature based on the detection signal indicating the tire air pressure transmitted from the air pressure detection unit 12 and the detection signal indicating the temperature in the tire, and performs data communication as data regarding the tire air pressure. It also plays the role of telling the department 14.

In addition, the control unit 13 controls data transmission from the data communication unit 14, and transmits road surface data to the data communication unit 14 at a timing when data transmission is desired to be performed. To be done.

For example, the control unit 13 extracts the feature amount of the tire G each time the tire 3 makes one rotation, and makes the data communication unit 14 at a rate of once or plural times each time the tire 3 makes one or more rotations. The road surface data is being transmitted. For example, the control unit 13 transmits, to the data communication unit 14, road surface data including the feature amount of the tire G extracted during one rotation of the tire 3 when transmitting road surface data to the data communication unit 14. There is.

Further, the control unit 13 may, for example, calculate the wear state at a rate of once during one run, for example, the data communication unit performs data on the wear state once in a predetermined period after the vehicle starts running. I'm telling you. Further, when there is a request from a torque control ECU 24 described later, the control unit 13 transmits data related to the load to the data communication unit 14. Furthermore, the control unit 13 transmits data on tire air pressure to the data communication unit 14 every predetermined regular transmission cycle. In addition, since tire air pressure can be used for correction of wear condition and load calculation, the control unit 13 may use the tire when transmitting data on the wear condition and data on the load to the data communication unit 14 as necessary. It also sends data on air pressure.

Here, the control unit 13 creates the road surface data, the data on the load, and the data on the wear state among the data described here, based on the detection signal of the vibration sensor unit 11. However, since the detection targets are different, the control unit 13 performs processing using different algorithms such as performing different waveform processing on the detection signal of the vibration sensor unit 11 in order to create each data.

That is, in order to obtain the feature value of the tire G for road surface data, in order to obtain the contact speed and the rotational speed of the tire 3 for data on the load, and for obtaining the rotational speed of the tire 3 for data on the wear state, Do different processing. For example, in order to obtain the feature amount of the tire G, for example, a frequency component of 0 kHz to 5 kHz is extracted from detection signals of the vibration sensor unit 11 using filters of five bands for each 1 kHz band, Obtain the power spectrum value of the frequency band. In addition, in order to obtain the contact speed and the rotational speed of the tire 3, it is sufficient to perform waveform processing to the extent that the maximum value and the minimum value of the detection signal of the vibration sensor unit 11 can be recognized. Is not necessary. Therefore, processing by different algorithms will be performed depending on the required data.

Therefore, as described later, in the tire system 100 according to the present embodiment, the required data can be grasped by the request signal from the vehicle body side system 2, and the detection target is grasped based on the request signal. The algorithm can be switched according to.

The data communication unit 14 corresponds to a first data communication unit that performs bidirectional communication with the vehicle body side system 2. Various forms of bi-directional communication can be applied. Bluetooth communication including BLE (abbreviation of Bluetooth Low Energy) communication, wireless LAN such as wifi (abbreviation of Local Area Network), Sub-GHz communication, ultra wide band Communication, ZigBee, etc. can be applied. "Bluetooth" is a registered trademark.

For example, when various data such as road surface data are transmitted from the control unit 13, the data communication unit 14 performs data transmission at that timing. The timing of data transmission from the data communication unit 14 is controlled by the control unit 13. For example, in the case of road surface data, data transmission from the data communication unit 14 is performed each time the tire 3 is sent from the control unit 13 each time the tire 3 makes one rotation or a plurality of rotations.

The power supply unit 15 is a power supply of the tire-side device 1 and supplies the electric power to the respective components provided in the tire-side device 1 so that the respective components can be operated. The power supply unit 15 is configured of, for example, a battery such as a button battery. Since the tire side device 1 is provided in the tire 3, battery replacement can not be easily performed, and therefore, it is necessary to reduce power consumption. In addition to the battery, the power supply unit 15 can also be configured by a power generation device, a storage battery, and the like. When the power supply unit 15 is configured to have a power generation device, the problem of battery life is reduced compared to the case where it is a battery, but large power generation is difficult, so the problem of reducing power consumption is the battery The same as in the case of

On the other hand, the receiver 21 receives various data such as road surface data transmitted from the tire-side device 1 to detect a road surface state and a wear state, and detects a load applied to each wheel. The receiver 21 also performs processing of outputting road surface data to the vehicle communication device 25. As the road surface data at this time, the road surface data transmitted from each tire side device 1 may be used as it is, or as described later, the road surface data showing the detection result of the road surface condition detected by the receiver 21 You may use. Then, based on this, the road surface data is sent from the vehicle communication device 25 to the communication center 200 collecting road information and the like. The receiver 21 also performs processing for acquiring more accurate road surface data from the communication center 200 through the vehicle communication device 25.

Specifically, the receiver 21 is configured to include the data communication unit 21a and the control unit 21b.

The data communication unit 21a is a part that constitutes the second data communication unit, and receives various data transmitted from the data communication unit 14 of the tire-side device 1 and transmits the data to the control unit 21b. The data communication unit 21 a also plays a role of transmitting a request signal or the like transmitted from the control unit 21 b to each tire-side device 1.

The control unit 21 b is configured by a well-known microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and performs various processes in accordance with a program stored in the ROM or the like.

Specifically, the control unit 21b stores and stores the support vector for each type of road surface, and detects the road surface state based on the support vector and the feature amount included in the road surface data. The support vector is a feature that serves as an example, and is obtained, for example, by learning using a support vector machine. A vehicle equipped with the tire side device 1 is run experimentally for each kind of road surface, and at that time, the feature quantity extracted from the detection signal of the vibration sensor unit 11 is learned for a predetermined number of tire rotations, The feature vector extracted as a predetermined number of times is taken as a support vector. For example, feature amounts for one million rotations are learned for each type of road surface, and typical feature amounts for 100 rotations are extracted therefrom as support vectors. The similarity between the support vector and the feature amount included in the road surface data is determined, and the type of the road surface to which the support vector with high similarity belongs belongs to the road surface condition on the traveling road surface of the vehicle. In addition, about the calculation method of a feature-value, a similarity degree, etc., since it becomes well-known in the above-mentioned patent document 1 grade | etc., It abbreviate | omits description here, but can apply various known methods.

Furthermore, the control unit 21b transmits the detection result of the road surface condition or road surface data to the vehicle communication device 25 to transmit it to the communication center 200, or inputs the accurate road surface data transmitted from the communication center 200 to the vehicle communication device 25. Processing to acquire the road surface condition.

In addition, the control unit 21b controls the load applied to each wheel on which the tire 3 is mounted, the tire air pressure, and the tire 3 based on the data on the load, the data on the tire pressure, and the data on the wear state. The wear condition is detected. In the case of the present embodiment, the data regarding the road surface data and the tire pressure described above are transmitted at the timing determined from the tire device 1, and the data regarding the load and the data regarding the wear state are based on the request signal from the control unit 21b. I am sending it. As described later, when the request signal from the brake ECU 23 or the torque control ECU 24 is transmitted to the control unit 21b, the request signal is transmitted from the control unit 21b to the tire-side device 1, as described later. Be done. Further, the data on the wear state is requested by outputting a request signal to the tire side device 1 from the control unit 21b so that the wear state can be detected at least once during one traveling. Here, for example, the control unit 21b relates to the wear state from the control unit 21b to the tire side device 1 once within a predetermined time after an ignition switch (hereinafter referred to as IG) 30 corresponding to a start switch for enabling the vehicle to travel is turned on. A request signal of data is transmitted. The wear state may be detected at least once during one run, but the processing load on the tire-side device 1 can be further reduced by performing the detection only once. It is also possible to reduce the power required for data transmission.

With regard to the load, the ground contact area is determined based on the time of the ground contact zone included in the data on the load and the time taken for one rotation of the tire obtained from the data on the rotational speed of the tire 3 can do. Moreover, when the tire size of each wheel is different or the tire air pressure is different, the load applied to each wheel can be more accurately obtained by performing correction according to these.

With regard to tire air pressure, data on tire air pressure can be transmitted from the tire side device 1 to obtain tire air pressure under a reference temperature. Here, although the result of calculating the tire air pressure under the reference temperature in the tire side device 1 is transmitted as data related to the tire air pressure, it is possible to transmit the measured value of the tire air pressure and the data of the temperature inside the tire. You can also In that case, based on the data, the control unit 21b converts the tire pressure into the tire pressure under the reference temperature.

The wear state can be calculated based on data on the rotational speed of the tire 3 included in the data on the movement distance information of the vehicle transmitted from the navigation ECU 22 and the wear state as described later. In other words, if the depth of the groove formed in the tread 31 of the tire 3 changes, the circumference of the tire 3 decreases, so even after traveling the same distance, the after-wear direction is better than before the tire 3 wear. The rotation speed of the tire 3 is increased. Therefore, based on the difference between the travel distance of the vehicle obtained by the information from the navigation ECU 22 and the travel distance of the vehicle estimated from the tire speed and the tire diameter included in the data on the wear state, Wear condition can be calculated. Furthermore, when traveling, the load applied to each wheel deforms the tire 3, and the tire 3 also deforms according to the tire pressure. For this reason, if the rotational speed of each tire 3 or the moving distance of the vehicle estimated based on the rotational speed of each tire 3 is corrected based on the load applied to each wheel calculated as described above or the tire air pressure, the wear state is more accurately Can also be calculated.

In addition, about the calculation method of the load added to each wheel, tire air pressure, and the wear condition of the tire 3, since it is already known, although description is abbreviate | omitted here, various techniques which are publicly known are applied. it can.

In addition, the control unit 21b transmits the detection result of the road surface condition or the road surface condition transmitted from the communication center 200 to the notification device 26, and notifies the driver of the road surface condition from the notification device 26, as necessary. As a result, the driver can keep in mind the driving corresponding to the road surface condition, and the danger of the vehicle can be avoided. For example, the road surface state may be always displayed through the notification device 26, or the road surface state may be displayed only when the road surface state requires more careful operation such as a wet road, a frozen road or a low μ road. It may be displayed to warn the driver. Similarly, the control unit 21b transmits the detection result of the worn state and the detection result of the tire air pressure to the notification device 26, and transmits each detection result to the driver through the notification device 26. Thus, the driver can know that it is time to change the tire or to adjust the tire pressure.

Further, the control unit 21b transmits the road surface state and the load of each wheel to the ECU for executing the vehicle motion control such as the brake ECU 23 and the torque control ECU 24, and based on the transmitted road surface state and the load of each wheel Vehicle motion control is performed.

The navigation ECU 22 is provided in the navigation system, acquires information from a non-transitional tangible storage medium such as a memory storing road information and the like, and measures the current position of the vehicle based on position information of GPS (abbreviation of Global Positioning System) satellites. Etc. In other words, the navigation ECU 22 performs various processes related to road guidance and the like. The tire system 100 according to the present embodiment uses road information handled by the navigation ECU 22, current position information, and travel distance information of the vehicle, and the navigation ECU 22 constitutes a position information acquisition unit.

Specifically, road information and current position information are used to indicate the relationship between the road on which the vehicle is currently traveling and the current position and road surface data, and the like, and are transmitted from the navigation ECU 22 to the receiver 21. Further, these pieces of information are transmitted to the vehicle communication device 25 from the navigation ECU 22 directly or via the control unit 21b, and when the road surface data is transmitted from the vehicle communication device 25 to the communication center 200, they are associated with the road surface data. Sent. As a result, in the communication center 200, it is possible to grasp which place the road surface state indicated by the road surface data is. Further, the travel distance information of the vehicle is transmitted to the control unit 21b. And the control part 21b is detecting the wear condition of the tire 3 based on the movement distance information of a vehicle.

The brake ECU 23 constitutes a braking control device that performs various brake control, and automatically generates a brake fluid pressure by driving an actuator for controlling the brake fluid pressure to pressurize the wheel cylinder for braking force. Generate The brake ECU 23 can also control the braking force of each wheel independently.

As described above, the control unit 21b transmits the detection result of the road surface state and the load to the brake ECU 23. Based on this, the brake ECU 23 adjusts the braking force according to the road surface condition, or controls the braking force of each wheel according to the load of each wheel, thereby controlling the brake according to the road surface condition and the load. It is carried out. In addition, when performing brake control according to a load, in order to require the data regarding a load, brake ECU23 outputs the request signal of the data regarding a load with respect to the control part 21b. Based on this, the control unit 21b transmits the request signal of the data related to the load to the tire side device 1 through the data communication unit 21a. Further, the brake ECU 23 performs vehicle speed calculation and the like based on a detection signal of a wheel speed sensor (not shown) and the like, and transmits the calculation result to the receiver 21 as vehicle speed information.

The torque control ECU 24 performs control of the drive torque, and performs control of actively moving the drive force of the left and right wheels, for example, torque vector differential control. The torque control ECU 24 achieves torque distribution corresponding to the load of each wheel by moving the driving force of the left and right wheels according to the load based on the detection result of the load transmitted from the control unit 21b. In addition, when performing torque control according to a load, the torque control ECU 24 outputs a request signal of data relating to the load to the control unit 21 b because it requires data relating to the load. Based on this, the control unit 21b transmits the request signal of the data related to the load to the tire side device 1 through the data communication unit 21a.

The vehicle communication device 25 can perform road-to-vehicle communication, and exchanges information with the communication center 200 via a communication system (not shown) installed on, for example, a road. In the case of this embodiment, the vehicle communication device 25 plays a role of transmitting the road surface data transmitted from the receiver 21 to the communication center 200 or receiving more accurate road surface data from the communication center 200.

The notification device 26 is formed of, for example, a meter indicator, and is used to notify the driver of a road surface condition that requires more careful driving, a decrease in tire air pressure, and a notification of wear of the tire 3. When the notification device 26 is configured by a meter indicator, the driver is disposed at a visible position during driving of the vehicle, for example, installed in an instrument panel of the vehicle. When the meter display receives data indicating the road surface condition, tire pressure or wear condition from the receiver 21, it can visually notify the driver by performing display in such a manner that the contents can be grasped .

The notification device 26 can also be configured by a buzzer, a voice guidance device, or the like. In that case, the notification device 26 can aurally notify the driver of the road surface condition, the tire pressure or the wear condition by means of a buzzer sound or voice guidance. Moreover, although the meter display was mentioned as the example as the alerting | reporting apparatus 26 which alert | reports visual, you may comprise the alerting | reporting apparatus 26 by the indicator which displays information, such as a head-up display.

The tire system 100 according to the present embodiment is configured as described above. In addition, each part which comprises the vehicle body side system 2 is connected through in-vehicle LAN (abbreviation of Local AreaNetwork) by CAN (abbreviation of Controller AreaNetwork) communication etc., for example. Therefore, each part can communicate information with each other through the in-vehicle LAN.

On the other hand, the communication system 200 that exchanges information regarding the road surface data with the tire system 100 performs a project of collecting road information and providing road information to vehicles and the like. Although the communication center 200 and the vehicle communication device 25 may be capable of direct communication, the communication center 200 can communicate with the vehicle communication device 25 through communication systems installed at various places such as roads. There is.

In the case of the present embodiment, the communication center 200 manages, as a database, information on road surface conditions for each road location in the map data, and based on the received road surface data, mapping of the road surface conditions changing momentarily Is going. That is, the communication center 200 updates the road surface condition information for each road location in the map data based on the received road surface data. The communication center 200 provides road surface data to the vehicle from the database.

Specifically, the communication center 200 collects road surface data of the road traveled by the vehicle sent from the vehicle, and updates the road surface data of each road in the map data based on the road surface data. The communication center 200 also collects weather information and the like, corrects each road surface data based on the weather information and the like, and updates it as more reliable road surface data. For example, the communication center 200 acquires the snow amount and information on the frozen road surface as weather information, and for the snow road surface and the frozen road surface, more accurate road surface data is sequentially stored by updating the road surface data corresponding thereto. I am trying to Then, the communication center 200 transmits the road surface data stored in the database to the vehicle to thereby transmit more accurate road surface data to the vehicle. At this time, the communication center 200 collects road surface data from a large number of vehicles and updates the road surface data of each road in the map data stored in the database. Not only can it acquire about the road surface data of the road which is going to travel.

Subsequently, the operation of the tire system 100 according to the present embodiment will be described with reference to the flowcharts shown in FIG. 6 to FIG.

Initially, with reference to FIG. 6, the tire side process which each tire side apparatus 1 performs is demonstrated. This process is executed when the waveform of the detection signal of the vibration sensor unit 11 exceeds the predetermined threshold and the control unit 13 is activated, and is executed by the control unit 13 every predetermined control cycle. Ru.

First, when the control unit 13 is switched to the activated state, at Step S100, the control unit 13 determines whether the vehicle is traveling, that is, is traveling or being stopped. This process is executed based on, for example, a detection signal of the vibration sensor unit 11. That is, if the output voltage waveform of the detection signal of the vibration sensor unit 11 indicates the waveform for one rotation of the tire, it is determined that the vehicle is traveling. The fact that the tire 3 has made one rotation is determined based on the time axis waveform of the detection signal of the vibration sensor unit 11. That is, since the detection signal draws the time axis waveform shown in FIG. 4, one rotation of the tire 3 can be grasped by confirming the first peak value and the second peak value of the detection signal. In addition, since the rotation of the tire 3 is in agreement with the traveling of the vehicle, it can be detected based on the rotation of the tire 3 whether the vehicle is traveling or being stopped.

If an affirmative determination is made here, the process proceeds to step S110, and the control unit 13 determines whether a request signal is received from the vehicle body side system 2. As described above, when the control unit 21 b receives a request signal of data related to the load from the brake ECU 23 or the torque control ECU 24, the control unit 21 b transmits it to the tire side device 1. In addition, the control unit 21b transmits a request signal of data relating to the wear state to the tire side device 1 once in a predetermined period after the IG is turned on. When these request signals are received by the tire device 1, an affirmative determination is made in step S110.

Then, if an affirmative determination is made in step S110, the process proceeds to step S120, and the control unit 13 performs measurement according to the instruction of the request signal. That is, if the received request signal is a request signal of data related to load, the control unit 13 measures the rotational speed of the ground section or the tire 3 based on the detection signal of the vibration sensor unit 11, and the load including those data Create data about Further, if the received request signal is a request signal of data regarding the wear state, the control unit 13 calculates the rotational speed of the tire 3 and creates data regarding the wear state including the data. Further, as the data regarding the wear state, data regarding the tire pressure and data regarding the load may be created as necessary.

Thereafter, the process proceeds to step S130, the control unit 13 executes a data transmission process of transmitting the data created in step S120 to the tire-side device 1, and repeats the process from step S100.

On the other hand, when a negative judging is carried out at Step S110, it progresses to Step S140 and control part 13 measures in normal mode. Specifically, the characteristic amount of the tire G is extracted by performing waveform processing of the vibration waveform indicated by the detection signal of the vibration sensor unit 11, and road surface data including the extracted characteristic amount is created. This process may be performed every one rotation of the tire 3 or may be performed every plural rotations. In addition, the tire air pressure under the reference temperature is calculated based on the detection signals of the pressure sensor 12a and the temperature sensor 12b in the air pressure detection unit 12 for each predetermined periodic transmission cycle, and data on the tire air pressure including it is created.

Thereafter, the process proceeds to step S130, the control unit 13 executes data transmission for transmitting road surface data or data related to tire air pressure, and repeats the process from step S100.

Furthermore, when the vehicle stops, a negative determination is made in step S100, so the control unit 13 proceeds to step S150 and determines whether the duration after stopping is within a predetermined time, for example, 5 minutes. For example, the control unit 13 counts an elapsed time when the negative determination is made for the first time in step S100 and the negative determination is continuously continued in step S100, and determines whether the elapsed time is within a predetermined time. ing. That is, in the tire side device 1, since the on / off state of the IG can not be grasped, the control unit 13 determines that the case where the continuation time after stopping has reached the predetermined time is the situation where the IG is turned off. ing.

Then, when a predetermined time has elapsed since the vehicle was stopped, a negative determination is made in step S150, so the control unit 13 switches to the sleep state and ends the process. After this, for example, the control unit 13 maintains the sleep state until the vehicle starts traveling again and is switched to the activation state based on the detection signal of the vibration sensor unit 11. In this way, the tire side process ends.

Next, with reference to FIG. 7, in the vehicle body side system 2, the vehicle body side processing performed by the control unit 21 b of the receiver 21 will be described. This process is executed every predetermined control cycle when the IG switch 30 is turned on and the control unit 21b is powered on.

First, in step S200, the control unit 21b determines whether the vehicle is traveling. This process is executed based on, for example, the vehicle speed information transmitted from the brake ECU 23. The control unit 21b determines that the vehicle is traveling when the vehicle speed is not zero. If an affirmative determination is made here, the process proceeds to step S210, and if a negative determination is made, the process ends.

In the following step S210, the control unit 21b determines whether there is a request from another ECU. As described above, the brake ECU 23 and the torque control ECU 24 output a request signal of data related to the load when performing the brake control and the torque control according to the load. If the control part 21b receives the request | requirement signal of the data regarding this load, it will affirmation determination by step S210. If an affirmative determination is made here, the process proceeds to step S220, and the control unit 21b transmits a request signal of data related to load to the tire-side device 1. If a negative determination is made here, the process proceeds to step S230.

In step S230, the control unit 21b determines whether the cumulative traveling time after the IG switch 30 is turned on is 10 minutes or less. If an affirmative determination is made here, the process proceeds to step S240, and the control unit 21b determines whether detection of a wear state has been instructed, that is, whether a request signal for data regarding the wear state has been transmitted. Since the wear of the tire 3 does not rapidly progress, it is considered to be preferable if the wear state can be detected at least once during one running. For this reason, from the time the IG switch 30 is turned on to the time it is turned off, that is, once during one travel, data on the wear state is requested to the tire side device 1. Here, if the affirmative determination is made in step S230 and the negative determination is made in step S240, the process proceeds to step S250 so that the cumulative running time after the IG switch 30 is turned on is worn out within a predetermined time, for example 10 minutes. Send a request signal for data on

On the other hand, if the cumulative travel time after IG ON exceeds the predetermined time or the request signal of data relating to the wear state is already transmitted, and if the negative determination is made in step S230 or the positive determination is made in step S240, step S260 Go to Then, in step S260, a data waiting process is performed. This data waiting process will be described with reference to FIG.

The data waiting process is executed by the control unit 21b at predetermined control intervals. First, in step S300, data reception processing for receiving data sent from each tire-side device 1 is executed. And if data reception is performed, it will progress to Step S310, and control part 21b will judge whether received data are data about a load. If an affirmative determination is made here, the process proceeds to step S320, calculates the load of each wheel by the method described above based on the data on the load from each tire-side device 1, and transmits the result to torque control ECU 24 or brake ECU 23. . Thereafter, the process ends.

In addition, if the negative determination is made in step S310, the process proceeds to step S330, and it is determined whether the received data is data regarding a wear state or data regarding tire air pressure. If an affirmative determination is made here, the process proceeds to step S340. Then, if the received data is data relating to the wear state, the wear state of each tire 3 is calculated by the method described above based on this data and the travel distance information of the vehicle transmitted from the navigation ECU 22, and the result is reported Transmit to 26. If the received data is data relating to tire air pressure, the tire air pressure is acquired from this data, and the result is transmitted to the notification device 26. Thereafter, the process ends.

Furthermore, when a negative determination is made also in step S330, the process proceeds to step S350. In this case, since the received data is road surface data, the feature amount included in the data is compared with all the support vectors to determine the similarity, and the road surface condition of the traveling road of the vehicle is determined based on the similarity. . Then, the determination result of the road surface state is transmitted to the brake ECU 23, and the process is ended.

As described above, in the stand-by process, the data transmitted from each tire-side device 1 is received, and the road surface state and the wear state are detected according to the type of the received data, or the load applied to each wheel is detected. And the result can be transmitted to each part of the vehicle body side system 2.

Further, the vehicle body side system 2 and the communication center 200 communicate with each other. As a result, mapping of the road surface state by the communication center 200 is performed, and provision of road surface data indicating the road surface state and the like collected in the database of the communication center 200 to the vehicle body side system 2 is performed.

Mapping by the communication center 200 will be described with reference to FIGS. 9 and 10. FIG. 9 shows the details of the mapping data transmission process executed by the control unit 21b for the mapping of the communication center 200, and is executed every predetermined control cycle. FIG. 10 shows the mapping process performed by the communication center 200, which is executed at predetermined control cycles by a control unit such as a microcomputer (not shown) provided in the communication center 200.

First, as shown in FIG. 9, in step S400, the control unit 21b performs current position detection. This process is performed by obtaining current position information from the navigation ECU 22. Then, in step S410, the control unit 21b transmits current position information to the communication center 200. At this time, ID information individually determined for each vehicle is added to the current position information and transmitted to the communication center 200 so that the vehicle can be specified on the communication center 200 side.

On the other hand, as shown in FIG. 10, the communication center 200 performs data reception processing in step S500, and receives data from the vehicle body side system 2 of each vehicle. Then, when the communication center 200 receives data, the process proceeds to step S510, and based on the current position information included in the data, it is determined whether the current position of the vehicle that has sent the data is a position required for mapping. judge. If a negative determination is made here, the processing is ended as it is, but if a positive determination is made, the processing proceeds to step S520, where a request signal for requesting road surface data is sent to the vehicle that has sent data. Then, in step S530, road surface data reception processing is performed.

Further, as shown in FIG. 9, after the process of step S410, the control section 21b proceeds to step S420, and determines whether or not the request signal of the road surface data has been received. As described above, when the request signal of the road surface data is transmitted from the communication center 200, an affirmative determination is made in step S420. Then, if an affirmative determination is made in step S420, the process proceeds to step S430, the road surface data is transmitted, and the process ends. At this time, the road surface data including the feature amount transmitted from each tire side device 1 may be transmitted as it is, or may be road surface data indicating the detection result of the road surface condition in the control unit 21b. Of course, the road surface data may include both the feature amount and the detection result of the road surface state.

Furthermore, when the request signal of the road surface data is sent from the communication center 200, the request signal for requesting the road surface data is outputted to the tire side device 1, and the road surface data is created even if it is not in the normal measurement mode. It can also be made to transmit. That is, when the vehicle tries to travel to a point required by the communication center 200, the communication center 200 instructs the vehicle side to transmit road surface data, and in response to the instruction, the vehicle side system 2 receives the tire side It is also possible to request the device 1 to transmit road surface data. In this case, the tire side device 1 creates road surface data based on the detection signal of the vibration sensor unit 11 and transmits the road surface data to the vehicle body side system 2 even if it is not the normal mode measurement. Also, since the communication center 200 can estimate the point at which the vehicle will travel from the current position information transmitted from the tire-side device 1, the position information of the point before the vehicle travels the point Can be transmitted to the vehicle body side system 2. As a result, when the vehicle travels the point, the receiver 21 can issue a request signal to the tire-side device 1 to obtain the road surface data of the point.

Then, when the road surface data is transmitted from the vehicle side, after data reception is performed in step S530 shown in FIG. 10, the process proceeds to step S540, and the communication center 200 performs mapping based on the received road surface data. That is, based on the received road surface data, the communication center 200 updates the road surface state information for each road location in the map data stored in the database. Thereby, mapping of the road surface condition which changes every moment is performed.

Since the communication center 200 manages a database storing road surface state information for each road location, the vehicle transmits the road surface data from the communication center 200 to the vehicle communication device 25 of each vehicle. It is possible to provide road surface data of the road which is about to travel.

As described above, in the tire system 100 of the present embodiment, the vehicle body side system 2 outputs a request signal to each tire side device 1 to transmit necessary data. Specifically, when data on the wear state and data on the load are required, a request signal indicating that the data is necessary is issued.

Therefore, the control unit 13 of each tire side device 1 grasps the state of the vehicle based on the request signal, and transmits the required data to the vehicle body side system 2 at an appropriate timing according to the state of the vehicle. Can. Further, when processing the detection signal of the vibration sensor unit 11, the control unit 13 can cope with a plurality of detection targets by switching an algorithm for processing the detection signal based on the request signal. Thereby, based on the detection signal of one vibration sensor unit 11, the detection result is obtained by one control unit 13. Therefore, it is not necessary to provide a plurality of vibration sensors and a plurality of microcomputers for each tire side device 1 or a microcomputer having a high processing capability, and increase in weight and physical size of the tire side device 1 can be suppressed At the same time, it is possible to reduce power consumption.

Also, for the road surface data that is required with relatively high frequency rather than transmitting the request signal corresponding to all the detection targets from the vehicle body side system 2, the predetermined timing as the normal mode measurement is made by the tire side device 1 To be done in Therefore, the road surface data can be transmitted without the request signal from the vehicle body side system 2. However, road surface data may also be transmitted based on a request signal from the vehicle body side system 2.

(Other embodiments)
The present disclosure has been described based on the above-described embodiment, but is not limited to the embodiment, and includes various modifications and variations within the equivalent range. In addition, various combinations and forms, and further, other combinations and forms including only one element, or more or less than these elements are also within the scope and the scope of the present disclosure.

For example, in the above embodiment, the road surface condition, the worn condition of the tire 3, the load applied to each wheel, and the tire air pressure are exemplified as the plurality of types of detection targets related to the tire 3. However, these are just one example. That is, based on detection signals corresponding to a plurality of types of detection targets outputted by the sensing unit such as the vibration sensor unit 11 or the air pressure detection unit 12, data concerning the detection target is created The present disclosure can be applied to the case of communicating to (2). Of course, it is not necessary that all of the road surface condition, the worn condition of the tire 3 and the load applied to each wheel need to be detected, and one or more of them may be detected. One may be the detection target. In addition, although the vibration sensor unit 11 and the air pressure detection unit 12 are exemplified as the sensing unit, a detection signal for detecting another detection target may be output.

In addition, various values acquired for detection of a plurality of types of detection targets related to the tire 3, such as the road surface state, the worn state of the tire 3, the load applied to each wheel, and the like may also be detection targets. For example, in the above embodiment, the characteristic amount of the tire G, the contact zone and the rotational speed of the tire 3 are determined from the detection signal of the vibration sensor unit 11, and based on these, plural types of detection targets related to the tire 3 described above Detected The feature quantities of the tire G, the contact zone, the rotational speed of the tire 3 and the like can be objects to be detected from the detection signal of the vibration sensor unit 11 as well. Furthermore, even in the case where detection targets other than the detection target mentioned here are to be detected, the tire side device 1 can detect the target based on the request signal from the vehicle body side system 2. Then, the detection result can be transmitted from the tire side device 1 at an appropriate timing.

Further, various values can be grasped as a plurality of detection targets even if they have the same value. For example, the feature amount of the tire G can be grasped as a plurality of detection targets. Specifically, there are various waveform processing methods for the feature amount of the tire G, and each feature amount of the tire G obtained by each waveform processing can be grasped as a detection target. In this case, the feature quantities of the tire G are grasped as a plurality of detection targets. For example, if you want to make a more detailed determination of the road surface condition, for example, if you want to request a feature amount related to the dry road surface as a road surface condition, or if you want to request a feature amount on a wet road surface, frozen road or snow road. May be different. In that case, the algorithm of the waveform processing of the detection signal of the vibration sensor unit 11 may be different. In such a case, even if the feature amount of the tire G is to be detected in the same manner, the feature amounts to be obtained are different, so a plurality of detection targets are obtained.

Further, in the above embodiment, although the case where the vibration sensor unit 11 constituting the vibration detection unit is constituted by an acceleration sensor is exemplified, it may be constituted by another element capable of detecting vibration, such as a piezoelectric element. .

Further, in the above embodiment, data including a feature amount is used as road surface data indicating a road surface condition appearing in a detection signal of the vibration sensor unit 11. However, this is also merely an example, and other data may be used as road surface data. For example, integrated value data of vibration waveforms of each of the five regions R1 to R5 included in vibration data during one rotation of the tire 3 may be road surface data, or raw data of the detection signal itself may be road surface data.

Further, in the case of the above embodiment, in addition to the determination of the danger of the vehicle based on the road information and the information on the current position and the vehicle speed and the road surface data transmitted from the communication center 200 by the receiver 21 Plays a role as a control unit that gives an instruction of notification of the danger of However, this is merely an example, and a control unit may be provided separately from the receiver 21, or another ECU such as the navigation ECU 22 or the brake ECU 23 may function as the control unit.

Furthermore, the support vector is stored in the tire side device 1 so that the road surface state can be determined by the tire side device 1, and data indicating the determination result of the road surface state is sent to the vehicle body side system 2 as road surface data. You may Further, not only the method of calculating the load from the contact area ratio of each of the four wheels, but also the method of calculating from the relationship between the tire pressure and the contact area can be adopted. In that case, since the load can be calculated in each tire side device 1, the load can be calculated in each tire side device 1 and the calculation result can be transmitted to the vehicle body side system 2.

Moreover, although the tire side apparatus 1 was provided with respect to each of the some tire 3 in said each embodiment, what is necessary is just to be provided in at least one.

Claims

A tire side device (1) which is disposed in a tire (3) provided in a vehicle and transmits data on one of a plurality of detection objects related to the tire and which is disposed on the vehicle body side of the vehicle A tire system having a vehicle body side system (2) for receiving data relating to the detection target and acquiring a detection result of the detection target,
The tire side device is
Sensing units (11, 12) for outputting detection signals corresponding to the plurality of types of detection targets;
A signal processing unit (13) that performs signal processing on a detection signal of the sensing unit to create data regarding the detection target;
A first data communication unit (14) that performs two-way communication with the vehicle body side system and transmits the data on the detection target created by the signal processing unit to the vehicle body side system;
The body side system is
A second data communication unit (21a) that performs bidirectional communication with the tire-side device and receives data related to the detection target;
A control unit (21b) for acquiring a detection result of the detection target indicated by the data regarding the detection target based on the data regarding the detection target;
The vehicle body side system outputs, through the second data communication unit, a request signal for requesting which one of the plurality of types of detection targets is required to the tire side device.
The tire-side device creates data on a detection target indicated by the request signal from the plurality of types of detection targets based on the request signal, and transmits the data from the first data communication unit to the vehicle-side system Tire system to send.
The plurality of types of detection targets include a worn state of the tire and a road surface state on a traveling road surface of the tire,
The vehicle body side system transmits, as the request signal, a signal indicating that the object to be detected is in the worn state at least once during the period from when the start switch (30) of the vehicle is turned on to when it is turned off. And
When the tire side device transmits a signal indicating that the detection target is the wear state as the request signal, the tire side device creates data relating to the wear state and sends the data from the first data communication unit. When the request signal is not transmitted, the data on the road surface condition is created by performing the normal mode measurement as the detection target, and the data is transmitted from the first data communication unit when the request signal is not transmitted. The tire system according to claim 1, which transmits to the vehicle body side system.
The vehicle body side system transmits, as the request signal, a signal indicating that the object to be detected is in the worn state only once during the period from when the start switch is turned on to when it is turned off. The tire system according to Item 2.
The vehicle body side system transmits, as the request signal, a signal indicating that the object to be detected is in the worn state, within a predetermined time period, from a cumulative running time after the start switch is turned on. The tire system described in.
A vehicle communication system for transmitting data relating to the road surface condition to a communication center (200) that collects road information, and acquiring data relating to the road surface condition of the road on which the vehicle is traveling from the communication center (25) and a position information acquisition unit (22) for acquiring current position information of the vehicle, and transmitting the current position information to the communication center through the vehicle communication device, and When a request signal requesting data relating to the road surface condition is sent, a request signal indicating that the detection target is the road surface condition is transmitted to the tire device via the second data communication unit,
When the tire side device transmits a signal indicating that the detection target is the road surface state as the request signal, the tire side device creates data relating to the road surface state even if it is not the normal mode measurement. The tire system according to claim 2 or 3, wherein data is transmitted from the first data communication unit to the vehicle body side system.
The plurality of types of detection targets include the load of the wheel on which the tire is mounted,
The vehicle body side system transmits, as the request signal, a signal indicating that the detection target is the load used for vehicle motion control.
When the tire side device transmits a signal indicating that the detection target is the load as the request signal, the tire side device creates data relating to the load and transmits the data from the first data communication unit to the vehicle body The tire system according to claim 1, which transmits to a side system.
The plurality of types of detection targets include the load of the wheel on which the tire is mounted,
The vehicle body side system transmits, as the request signal, a signal indicating that the detection target is the load used for vehicle motion control.
When the tire side device transmits a signal indicating that the detection target is the load as the request signal, the tire side device creates data relating to the load and transmits the data from the first data communication unit to the vehicle body When the request signal is not transmitted, data on the road surface condition is created by creating data on the abrasion condition or performing the normal mode measurement as the detection target. The tire system according to any one of claims 2 to 4, wherein the data communication unit transmits the data to the vehicle body side system.