JP2017109574A - Tire air pressure monitoring system, monitoring device, and detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire air pressure monitoring system in which a sensor identifier of a detection device for detecting air pressure of a tire, does not have to be registered in a monitoring device in advance, and even when a new detection device is attached to a tire, the monitoring device can automatically perform update registration of the sensor identifier of each tire.SOLUTION: A tire air pressure monitoring system comprises: detection devices 2 each of which is provided on each tire 3; and a monitoring device 1 for monitoring tire air pressure. The monitoring device 1 associates sensor identifiers of the detection devices 2 on respective tire positions with the tire positions and stores them. The monitoring device 1 transmits a first request signal for requesting air pressure information, and the detection device 2 transmits a response signal containing the air pressure information, when the sensor identifier included in the request signal matches the sensor identifier of the detection device itself. The monitoring device 1 transmits a second request signal for requesting the sensor identifier to a tire position of the tire whose detection device does not transmit the response signal, then updates a registration content of the sensor identifier, when the detection device 2 does not transmit the response signal.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tire pressure monitoring system, and a monitoring device and a detection device constituting the tire pressure monitoring system.

  There is a tire pressure monitoring system (TPMS: Tire Pressure Monitoring System) that detects the air pressure of a tire provided in a vehicle and issues a warning to a user when the detected air pressure is abnormal. The tire pressure monitoring system includes a detection device provided for each tire and a monitoring device disposed on the vehicle body. The detection device detects the air pressure of the tire, and wirelessly transmits the air pressure signal including the air pressure information obtained by the detection and its own sensor identifier using radio waves in the UHF band. The monitoring device receives the air pressure signal transmitted from each detection device, and monitors the air pressure of each tire based on the received air pressure signal. Since the monitoring device stores the correspondence between each tire position where the tire is provided and the sensor identifier of the detection device provided on each tire, the monitoring device can recognize which tire has an abnormal air pressure. . When there is an abnormality in the tire air pressure, the monitoring device displays a warning on the tire air pressure abnormality and issues a warning.

  By the way, in order to make the wear state of the four tires uniform, tire rotation is generally performed in which the positions of the tires provided in the vehicle are interchanged. When the position of the tire is changed, the monitoring device needs to update the correspondence relationship between the four tire positions and the identifier.

  Patent Document 1 discloses a tire pressure monitoring system capable of automatically performing update registration of a sensor identifier when tire rotation is performed. The monitoring device is connected to a plurality of LF (Low Frequency) transmitting antennas arranged in the vicinity of each tire. When the ignition switch changes from the off state to the on state, the monitoring device transmits a request signal for requesting transmission of the sensor identifier to the detection device at each tire position. Upon receiving the request signal, the detection device returns its sensor identifier to the monitoring device. The monitoring device confirms that the sensor identifier transmitted from the detection device is one of the already registered sensor identifiers, and registers it in association with the corresponding tire position. As described above, according to the tire pressure monitoring system according to Patent Document 1, even if tire rotation is performed, the correspondence between each tire position and the sensor identifier can be updated.

  Patent Document 2 discloses an LF initiator system in which an activation signal is transmitted from a plurality of LF transmitting antennas arranged in the vicinity of each tire to a detection device of each tire and an air pressure signal transmitted from the activated detection device is received. A tire pressure monitoring system is disclosed. In particular, the monitoring device according to Patent Literature 2 transmits an activation signal together with a vehicle identifier unique to the vehicle to the detection device. The detection device stores a vehicle identifier unique to the vehicle on which the detection device is provided, and transmits a response signal to the monitoring device when the vehicle identifier transmitted together with the activation signal matches the vehicle identifier stored by itself. . Upon receiving the response signal, the monitoring device transmits a sensor identifier associated with the monitoring target tire position to the detection device. The detection device receives the sensor identifier transmitted from the monitoring device, compares it with its own sensor identifier, and transmits a pneumatic pressure signal to the monitoring device when it is determined that they match. According to the tire pressure monitoring system according to Patent Document 2 configured as described above, it is possible to prevent the signals transmitted from the respective detection devices from interfering when the detection devices of the host vehicle and the other vehicle are simultaneously activated. .

JP 2004-058964 A JP 2005-193861 A

  However, in the tire pressure monitoring system according to Patent Documents 1 and 2, it is necessary to register a sensor identifier in the monitoring device in advance in the vehicle assembly line. In addition, when a new detection device is provided on the tire or when the tire is replaced together with the detection device, it is necessary for a specialized worker to register a new sensor identifier in the monitoring device at the maintenance shop.

  The object of the present invention is not to register the sensor identifier of the detection device in the monitoring device in advance, and even when a new detection device is attached to the tire or when the tire is replaced together with the detection device, the monitoring device It is an object of the present invention to provide a tire pressure monitoring system, a monitoring device, and a detection device that can automatically update and register the sensor identifier of each tire.

  The tire pressure monitoring system according to this aspect is provided in each of a plurality of tires of a vehicle, and a plurality of detection devices that detect the tire air pressure and wireless communication between the detection devices, A tire pressure monitoring system comprising a monitoring device for monitoring air pressure, wherein the monitoring device includes a plurality of tire positions at which the plurality of tires are respectively provided, and the detection provided at each tire at the plurality of tire positions. A storage unit that stores an identifier of a device in association with the first and requests at least one of the tire positions, the identifier stored in the storage unit in association with the tire position, and requests arbitrary information A first request signal transmitter for transmitting the request signal, and the detection device receives a request signal receiver for receiving the first request signal and before receiving the request signal by the request signal receiver. A response signal transmission unit configured to transmit a response signal when the identifier included in the first request signal is identical to the identifier of the first request signal; A response signal receiving unit that receives the response signal in response, and reception of a response signal transmitted from the detection device corresponding to the identifier included in the first request signal in response to the first request signal. When it is determined that a determination unit that determines presence / absence and a response signal corresponding to the first request signal is not received, to the tire position where the response signal corresponding to the first request signal has not been transmitted A second request signal transmission unit that transmits at least a second request signal that requests the identifier, and the response signal transmission unit of the detection device receives the second request signal by the request signal reception unit. If at least myself A response signal including the identifier is transmitted, and the monitoring device transmits the second request signal when the response signal receiving unit receives the response signal according to the second request signal. An updating unit that associates the tire position and the identifier included in the response signal with each other and stores them in the storage unit.

  The monitoring device according to the present aspect is a monitoring device that is provided in each of a plurality of tires of a vehicle, performs wireless communication with a plurality of detection devices that detect the air pressure of the tires, and monitors the air pressure of each tire. A storage unit that stores a plurality of tire positions at which the plurality of tires are respectively provided, and an identifier of the detection device that is provided at each tire at the plurality of tire positions, and at least one of the tires A first request signal transmitting unit for transmitting a first request signal for requesting arbitrary information, including the identifier stored in the storage unit in association with the tire position, and the first request A response signal receiving unit that receives the response signal according to a signal, and a response signal transmitted from the detection device corresponding to the identifier included in the first request signal according to the first request signal Receiving And a tire position where a response signal according to the first request signal is not transmitted when it is determined that a response signal according to the first request signal is not received. A second request signal transmitter for transmitting at least a second request signal for requesting the identifier, and a response signal transmitted from the detection device in response to the second request signal and including the identifier of the detection device When the response signal receiving unit receives the update signal, the updating unit that stores the tire position where the second request signal is transmitted and the identifier included in the response signal in association with each other is stored in the storage unit. Prepare.

  The detection device according to the present aspect is provided in a tire of a vehicle and includes an identifier corresponding to its own identifier, and when receiving a first request signal requesting arbitrary information, the arbitrary information and its own identifier Including a request signal receiving unit that receives the first request signal that requests the air pressure information, and the first signal received by the request signal receiving unit. A response signal transmitting unit that transmits a response signal when the identifier included in the request signal matches the identifier of the request signal, wherein the response signal transmitting unit includes at least the request signal receiving unit. When a second request signal for requesting an identifier is received, a response signal including at least the identifier is transmitted.

  Note that the present application can be realized not only as a tire pressure monitoring system including such a characteristic processing unit, but also as a monitoring device and a detection device, and also as a tire pressure monitoring method using such characteristic processing as a step. Or can be realized as a program for causing a computer to execute such steps. Moreover, it is realizable as a semiconductor integrated circuit which implement | achieves a part or all of a tire pressure monitoring system, a detection apparatus, or a monitoring apparatus, or it can implement | achieve as another system containing a tire pressure monitoring system or a monitoring apparatus.

  According to the above, there is no need to register the sensor identifier of the detection device in advance in the monitoring device, and even when a new detection device is attached to the tire or the tire is replaced together with the detection device, the monitoring device It is possible to provide a tire pressure monitoring system, a monitoring device, and a detection device that can automatically update and register the sensor identifier of each tire.

It is a conceptual diagram which shows the example of 1 structure of the tire pressure monitoring system which concerns on embodiment of this invention. It is a block diagram which shows one structural example of the monitoring apparatus. It is a conceptual diagram which shows an example of a sensor identifier table. It is a block diagram which shows the example of 1 structure of a detection apparatus. It is a flowchart which shows the process sequence of the monitoring apparatus which concerns on air pressure monitoring. It is a flowchart which shows the process sequence of the monitoring apparatus which concerns on the update registration of a sensor identifier. It is a flowchart which shows the process sequence of a detection apparatus. It is a conceptual diagram which shows the correspondence of each tire position when a tire rotation and detection apparatus are not exchanged, and a sensor identifier. It is a graph which shows the processing content when replacement | exchange of a tire rotation and a detection apparatus is not performed. It is a conceptual diagram which shows the correspondence of each tire position when a tire rotation is performed, and a sensor identifier. It is a graph which shows the processing content when tire rotation is performed. It is a conceptual diagram which shows the correspondence of each tire position when sensor apparatus replacement | exchange is performed, and a sensor identifier. It is a graph which shows the processing content when replacement | exchange of a detection apparatus is performed. It is a graph which shows the processing content at the time of vehicle shipment in which the sensor identifier is not registered.

[Description of Embodiment of the Present Invention]
First, embodiments of the present invention will be listed and described. Moreover, you may combine arbitrarily at least one part of embodiment described below.

(1) The tire pressure monitoring system according to this aspect is provided in each of a plurality of tires of a vehicle, and a plurality of detection devices that detect the air pressure of the tires and wireless communication between the detection devices, A tire air pressure monitoring system comprising a monitoring device for monitoring the air pressure of each tire, wherein the monitoring device is provided at a plurality of tire positions at which the plurality of tires are respectively provided, and at each tire at the plurality of tire positions. A storage unit that associates and stores the identifier of the detection device, and the at least one tire position includes the identifier that is stored in the storage unit in association with the tire position, and requests arbitrary information. A first request signal transmitter for transmitting the first request signal, and the detection apparatus receives the first request signal and receives the first request signal at the request signal receiver. A response signal transmitting unit that transmits a response signal when the identifier included in the first request signal matches the identifier of the first request signal, and the monitoring device further includes the first request signal. A response signal receiving unit that receives the response signal according to a signal, and a response signal transmitted from the detection device corresponding to the identifier included in the first request signal according to the first request signal The tire that has not received a response signal corresponding to the first request signal when it is determined that a determination unit that determines presence / absence of reception and a response signal corresponding to the first request signal are not received A second request signal transmitting unit that transmits at least a second request signal for requesting the identifier to a location, and the request signal receiving unit includes the second request signal transmitting unit. If you receive When the response signal receiving unit receives the response signal corresponding to the second request signal, the monitoring apparatus transmits the response signal including the identifier of the second request signal. An update unit that associates the tire position to which the information is transmitted with the identifier included in the response signal and stores the identifier in the storage unit.

In this aspect, the storage unit of the monitoring device stores a plurality of tire positions and identifiers of the detection devices at the respective tire positions in association with each other. The monitoring device locally transmits a first request signal including an identifier and requesting arbitrary information to the tire position at an arbitrary timing. The identifier included in the first request signal is an identifier stored in the storage unit in association with the tire position to which the first request signal is transmitted. The detection device that has received the first request signal transmits a response signal including arbitrary information according to the request to the monitoring device when the identifier included in the received first request signal matches its own identifier. To do. The monitoring device receives the response signal transmitted from each detection device. Since the monitoring device performs wireless communication with the detection device using the identifier, information from the detection device provided in each tire can be acquired without error.
The arbitrary information is, for example, air pressure information, and the monitoring device can acquire the air pressure information without error. Further, the first request signal may be a signal requesting an identifier of the detection device as arbitrary information. Furthermore, the first request signal includes information for confirming that the identifier of the detection device is registered without error, specifically, the identifier transmitted from the monitoring device matches the identifier of the detection device. Information indicating whether or not there may be requested. Note that these pieces of information are examples of arbitrary information.
By the way, when the detection device is replaced or when the tire is replaced together with the detection device, the identifier included in the first request signal transmitted from the monitoring device to the detection device, and the identifier of the transmission destination detection device, Therefore, the detection apparatus does not transmit a response signal corresponding to the first request signal. In this case, the monitoring device transmits a second request signal for requesting the identifier to the detection device. When the detection device receives the second request signal, the detection device transmits a response signal including at least its own identifier to the monitoring device without collating with its own identifier. The response signal may include air pressure information and other information in addition to its own identifier. The monitoring device receives the response signal transmitted from the detection device, and stores the identifier included in the received response signal in the storage unit in association with the tire position related to the transmission destination of the second request signal. That is, the monitoring device updates the identifier stored in the storage unit.
Therefore, the monitoring device can determine whether or not the identifier stored in the storage unit has been updated from the reception status of the response signal transmitted from the detection device. And the monitoring apparatus can update the identifier which a memory | storage part memorize | stores automatically as needed, when a new detection apparatus is provided in the tire, when a tire is replaced | exchanged with the detection apparatus.

(2) The detection device includes an initial state storage unit that stores initial state information indicating an initial state in which the identifier of the monitoring device is not stored in the storage unit of the monitoring device, and the response signal transmission unit includes: It is preferable that the initial state storage unit stores the initial state information and transmits the response signal including at least the identifier of itself when the second request signal is received.

  According to this aspect, the detection device stores initial state information indicating an initial state in which its own identifier is not registered in the monitoring device. When the detection device receives the second request signal, the detection device transmits a response signal corresponding to the second request signal to the monitoring device only when the initial state information is stored. In other words, when the initial state information is not stored, the detection device does not transmit a response signal corresponding to the second request signal to the monitoring device even if it receives the second request signal. Therefore, it is possible to prevent a response signal corresponding to the second request signal from being transmitted unnecessarily from the detection device to the monitoring device, and to prevent erroneous registration of the identifier in the monitoring device.

(3) When the monitoring device receives the response signal corresponding to the second request signal, the monitoring device transmits an erasure signal including the received identifier and erasing the initial state information. The detecting device receives the erasing signal transmitted from the monitoring device, and the initial state storage unit stores the erasing signal when the erasing signal receiving unit receives the erasing signal. A configuration including an erasing unit that erases the initial state information is preferable.

  According to this aspect, when the monitoring device transmits the second request signal to the detection device and receives the response signal transmitted from the detection device in response to the second request signal, the monitoring device deletes the initial state information. The erasure signal is transmitted to the detection device. When the detection device receives the erase signal transmitted from the monitoring device, the detection device erases the initial state information. Accordingly, the detection device can avoid a situation in which the initial state information is erased and the monitoring device cannot update the identifier even though the identifier is not registered in the monitoring device. Note that the deletion of the initial state information includes not only the case where the initial state information itself is completely deleted, but also a process of changing the contents.

(4) The monitoring device according to this aspect is provided in each of the plurality of tires of the vehicle, and wirelessly communicates with the plurality of detection devices that detect the air pressure of the tire to monitor the air pressure of each tire. A monitoring device, a storage unit that stores a plurality of tire positions at which the plurality of tires are respectively provided and an identifier of the detection device provided at each tire at the plurality of tire positions in association with each other, and at least one A first request signal transmitting unit that transmits a first request signal for requesting arbitrary information including the identifier stored in the storage unit in association with the tire position, A response signal receiving unit that receives the response signal according to the first request signal, and a response signal that is transmitted from the detection device corresponding to the identifier included in the first request signal according to the first request signal Response A determination unit that determines whether or not a response signal is received, and when it is determined that a response signal corresponding to the first request signal is not received, a response signal corresponding to the first request signal is not transmitted A second request signal transmitter for transmitting at least a second request signal for requesting the identifier to the tire position; and transmitted from the detection device in response to the second request signal, including the identifier of the detection device When the response signal is received by the response signal receiving unit, the updating unit is configured to store the tire position where the second request signal is transmitted and the identifier included in the response signal in association with each other in the storage unit. With.

  According to this aspect, as in aspect (1), the monitoring device can store the identifier stored in the storage unit as necessary, such as when a new detection device is provided on the tire or when the tire is replaced with the detection device. Can be updated automatically.

(5) The detection device according to this aspect is provided in a vehicle tire, includes an identifier corresponding to the identifier of the vehicle, and receives the first request signal requesting arbitrary information. A detection device that wirelessly transmits a signal including the identifier, the request signal receiving unit receiving the first request signal including the identifier and requesting the air pressure information, and received by the request signal receiving unit A response signal transmission unit configured to transmit a response signal when the identifier included in the first request signal matches the identifier of the first request signal; and the response signal transmission unit includes: When a second request signal requesting at least the identifier is received, a response signal including at least the identifier is transmitted.

  According to this aspect, the detection apparatus can transmit information necessary for updating the identifier stored in the storage unit of the monitoring apparatus to the monitoring apparatus.

[Details of the embodiment of the present invention]
A specific example of a tire pressure monitoring system according to an embodiment of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to the claim are included.

FIG. 1 is a conceptual diagram showing a configuration example of a tire pressure monitoring system according to an embodiment of the present invention. The tire pressure monitoring system according to the present embodiment includes a monitoring device 1 provided at an appropriate location of the vehicle body, a plurality of detection devices 2 provided on each of the wheels of a plurality of tires 3 provided on the vehicle C, and a notification device. 4. In the tire pressure monitoring system of the present embodiment, the monitoring device 1 wirelessly communicates with each detection device 2 to acquire the air pressure information of each tire 3, and the notification device 4 performs notification according to the acquired air pressure information. . A plurality of LF transmission antennas 14 a corresponding to the respective tires 3 are connected to the monitoring device 1. For example, the LF transmission antenna 14a is provided at the right front, right rear, left rear, and left front tire positions of the vehicle C. The tire position is a position around the tire house and its surroundings, and is a position where the detection device 2 provided in each tire 3 can individually receive a signal transmitted from each LF transmission antenna 14a.
In the two-way communication method, the monitoring device 1 transmits a first request signal for requesting air pressure information of the tire 3 to each detection device 2 from each LF transmission antenna 14a to each detection device 2 by radio waves in the LF band. The first request signal includes the sensor identifier of the detection device 2 provided in the tire 3 at the tire position that is the transmission destination. As will be described later, the monitoring device 1 stores a relationship between each tire position where the tire 3 is provided and a sensor identifier of the detection device 2 provided on the tire 3 at the tire position. When the detection device 2 receives the first request signal including the same sensor identifier as its own sensor identifier, the detection device 2 detects the air pressure of the tire 3, and the response signal including the air pressure information obtained by the detection and the own sensor identifier. Is transmitted to the monitoring device 1 by radio waves in the UHF (Ultra High Frequency) band. The monitoring device 1 includes an RF receiving antenna 13a, receives a response signal transmitted from each detection device 2 by the RF receiving antenna 13a, and acquires air pressure information of each tire 3 from the response signal.
In the unidirectional communication method, the detection device 2 spontaneously transmits an air pressure signal at a predetermined timing. Since the monitoring device 1 stores the relationship between each tire position and the sensor identifier of the detection device 2 provided on the tire 3 at the tire position, each tire 3 is used by using the sensor identifier included in the air pressure signal. Air pressure information can be recognized.
Further, the monitoring device 1 according to the present embodiment causes the second request signal when a response signal cannot be received due to a flaw between the relationship between the stored tire position and sensor identifier and the actual relationship. Is transmitted, the contents of the sensor identifier stored automatically are updated.
Note that the LF band and the UHF band are examples of a radio wave band used when performing wireless communication, and are not necessarily limited thereto. The monitoring device 1 is connected to the notification device 4 via a communication line, and the monitoring device 1 transmits the acquired air pressure information to the notification device 4. The notification device 4 receives the air pressure information transmitted from the monitoring device 1 and notifies the air pressure information of each tire 3. Further, the notification device 4 issues a warning when the air pressure of the tire 3 is less than a predetermined threshold value.

  FIG. 2 is a block diagram illustrating a configuration example of the monitoring device 1. The monitoring device 1 includes a control unit 11 that controls the operation of each component of the monitoring device 1. The control unit 11 is connected to a storage unit 12, an in-vehicle receiving unit 13, an in-vehicle transmitting unit 14, a time measuring unit 15, an in-vehicle communication unit 16, and an input unit 17.

  The control unit 11 is a microcomputer having, for example, one or a plurality of CPUs (Central Processing Units), a multi-core CPU, a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output interface, and the like. The CPU of the control unit 11 is connected to the storage unit 12, the in-vehicle receiving unit 13, the in-vehicle transmitting unit 14, the time measuring unit 15, the in-vehicle communication unit 16, and the input unit 17 through an input / output interface. The control unit 11 controls the operation of each component by executing a control program stored in the storage unit 12, and executes the tire pressure monitoring process and the sensor identifier update registration process according to the present embodiment.

  The storage unit 12 is a nonvolatile memory such as an EEPROM (Electrically Erasable Programmable ROM) or a flash memory. The storage unit 12 stores a control program for executing tire pressure monitoring processing and sensor identifier update registration processing by the control unit 11 controlling the operation of each component of the monitoring device 1. The storage unit 12 stores a sensor identifier table.

  FIG. 3 is a conceptual diagram illustrating an example of a sensor identifier table. The sensor identifier table includes a plurality of tire positions, an antenna identifier for identifying the LF transmission antenna 14a disposed in the vicinity of the tire position, and a sensor identifier of the detection device 2 provided in the tire 3 at the tire position. It is stored in association. In the example shown in FIG. 3, sensor identifiers A, B, C, and D are associated with front right, right rear, left rear, and left front tire positions, respectively.

  An RF receiving antenna 13 a is connected to the in-vehicle receiving unit 13. The in-vehicle receiving unit 13 receives a signal transmitted from the detection device 2 using an RF band radio wave by the RF receiving antenna 13a. The in-vehicle receiving unit 13 is a circuit that demodulates the received signal and outputs the demodulated signal to the control unit 11. Although a UHF band of 300 MHz to 3 GHz is used as a carrier wave, the carrier wave is not limited to this frequency band.

  The in-vehicle transmission unit 14 is a circuit that modulates the signal output from the control unit 11 into an LF band signal and transmits the modulated signal to the detection device 2 from each of the plurality of LF transmission antennas 14a. As a carrier wave, an LF band of 30 kHz to 300 kHz is used, but it is not limited to this frequency band.

  The timer unit 15 is constituted by, for example, a timer, a real-time clock, and the like, starts timing according to the control of the control unit 11, and gives a timing result to the control unit 11.

  The in-vehicle communication unit 16 is a communication circuit that performs communication according to a communication protocol such as CAN (Controller Area Network) or LIN (Local Interconnect Network), and is connected to the notification device 4. The in-vehicle communication unit 16 transmits information related to the air pressure of the tire 3 to the notification device 4 under the control of the control unit 11.

  The notification device 4 is, for example, a display unit provided with a display unit or a speaker for notifying the information related to the air pressure of the tire 3 transmitted from the in-vehicle communication unit 16 by an image or sound, or a display provided on an instrument panel instrument. Etc. The display unit is a liquid crystal display, an organic EL display, a head-up display, or the like. For example, the notification device 4 displays air pressure information of each tire 3 provided in the vehicle C.

  The input unit 17 receives an ignition switch signal (hereinafter referred to as an IG switch signal) corresponding to the operation state of the ignition switch 5, and the control unit 11 is based on the IG switch signal input to the input unit 17. Thus, the operation state of the ignition switch 5 can be recognized.

  FIG. 4 is a block diagram illustrating a configuration example of the detection device 2. The detection device 2 includes a sensor control unit 21 that controls the operation of each component of the detection device 2. A sensor storage unit 22, a sensor transmission unit 23, a sensor reception unit 24, an air pressure detection unit 25, and a timer unit 26 are connected to the sensor control unit 21.

  The sensor control unit 21 is a microcomputer having, for example, one or a plurality of CPUs, a multi-core CPU, a ROM, a RAM, an input / output interface, and the like. The CPU of the sensor control unit 21 is connected to the sensor storage unit 22, the sensor transmission unit 23, the sensor reception unit 24, the air pressure detection unit 25, and the time measurement unit 26 via an input / output interface. The sensor control unit 21 reads a control program stored in the sensor storage unit 22 and controls each unit. The detection device 2 includes a battery (not shown) and operates with electric power from the battery.

  The sensor storage unit 22 is a nonvolatile memory. The sensor storage unit 22 stores a control program for the CPU of the sensor control unit 21 to perform processing related to detection and transmission of the air pressure of the tire 3. Further, a unique sensor identifier for identifying itself and the other detection device 2 is stored. Further, the sensor storage unit 22 stores in advance initial state information indicating that the sensor identifier of its own is in an initial state in which the sensor identifier is not registered in the monitoring device 1 at the time of shipment. The content of the initial state information is not particularly limited, and is arbitrary information such as a flag. The sensor storage unit 22 functions as an initial state storage unit that stores initial state information.

The air pressure detection unit 25 includes, for example, a diaphragm, and detects the air pressure of the tire 3 based on the deformation amount of the diaphragm that changes depending on the magnitude of the pressure. The air pressure detection unit 25 outputs a signal indicating the detected air pressure of the tire 3 to the sensor control unit 21. The sensor control unit 21 executes the control program to acquire the air pressure of the tire 3 from the air pressure detection unit 25 in response to the first request signal, and includes air pressure information and a sensor identifier unique to the detection device 2. A response signal is generated and output to the sensor transmitter 23.
In addition, you may provide the temperature detection part (not shown) which detects the temperature of the tire 3 and outputs the signal which shows the detected temperature to the sensor control part 21. FIG. In this case, the sensor control unit 21 generates a response signal including air pressure information, temperature, sensor identifier, and the like, and outputs the response signal to the sensor transmission unit 23.

  An RF transmission antenna 23 a is connected to the sensor transmission unit 23. The sensor transmission unit 23 modulates the response signal generated by the sensor control unit 21 into a UHF band signal, and transmits the modulated response signal using the RF transmission antenna 23a.

  An LF receiving antenna 24 a is connected to the sensor receiving unit 24. The sensor receiving unit 24 receives the first request signal transmitted from the monitoring device 1 using radio waves in the LF band by the LF receiving antenna 24 a and outputs the received signal to the sensor control unit 21.

Next, the procedure of tire pressure monitoring processing and sensor identifier update registration processing will be described.
FIG. 5 is a flowchart showing a processing procedure of the monitoring device 1 related to air pressure monitoring. 4 is a flowchart showing a processing procedure related to air pressure monitoring of the monitoring device 1. The control unit 11 of the monitoring device 1 executes the following processing at an arbitrary timing that requires air pressure information. For example, when the ignition switch 5 changes from the off state to the on state, the following processing is executed. The control unit 11 reads registered sensor identifiers corresponding to the four tire positions from the sensor identifier table, and transmits a first request signal that includes the read sensor identifiers and requests air pressure information to each tire position by LF transmission. The antenna 14a is sequentially transmitted to each tire position (step S11).

Specifically, as shown in FIG. 3, when the storage unit 12 associates sensor identifiers A, B, C, and D with the front right, rear right, rear left, and front left tire positions, the control unit 11 transmits a first request signal including the sensor identifier A from the LF transmitting antenna 14a located at the right front tire position to the area of the right front tire position. Further, the control unit 11 causes the first request signal including the sensor identifier B to be transmitted from the LF transmission antenna 14a at the right rear tire position to the region at the right rear tire position. Hereinafter, similarly, the control unit 11 sends a first request signal including sensor identifiers C and D from the LF transmitting antenna 14a at the left rear and left front tire positions to the region of the left rear and left front tire positions. Send it.
In addition, the control part 11 and the vehicle-mounted transmission part 14 which perform the process of step S11 function as a 1st request signal transmission part which transmits a 1st request signal to a tire position.

Next, the control unit 11 determines whether or not the in-vehicle reception unit 13 has received response signals including air pressure information from all four tire positions (step S12). That is, it is determined whether or not response signals respectively transmitted from the four detection devices 2 at the respective tire positions have been received. Since the response signal includes a sensor identifier, the vehicle in which the vehicle is mounted by collating the sensor identifier of each tire position stored in the storage unit 12 with the sensor identifier included in the response signal. It is possible to determine whether the response signal is transmitted from the detection device 2 provided on the C tire 3. Specifically, when a first request signal including the sensor identifier A is transmitted from the LF transmitting antenna 14a located at the right front tire position, a response signal transmitted from the detection device 2 in response to the first request signal When the sensor identifier A is included, the control unit 11 determines that a response signal has been received from the right front tire 3. Further, when the first request signal including the sensor identifier B is transmitted from the LF transmission antenna 14a located at the right rear tire position, the response signal transmitted from the detection device 2 according to the first request signal is detected by the sensor. When the identifier B is included, the control unit 11 determines that a response signal has been received from the right rear tire 3. Similarly, when the first request signal including the sensor identifiers C and D is transmitted from the LF transmission antennas 14a at the left rear and front left tire positions, the detection device 2 according to the first request signal. When the sensor identifiers C and D are included in the response signal transmitted from, the control unit 11 determines that the response signal has been received from the left rear and left front tires 3.
The in-vehicle receiving unit 13 and the control unit 11 that receive the response signal function as a response signal receiving unit, and the control unit 11 that executes the process of step S12 functions as a determination unit that determines whether or not the response signal is received. .

  When it determines with having received the response signal from all the tire positions (step S12: YES), the control part 11 is based on the response signal transmitted from the detection apparatus 2 of each tire position, and sets the pneumatic pressure information of each tire 3 It outputs to the alerting | reporting apparatus 4 (step S13), and complete | finishes a process. Specifically, the control unit 11 can recognize the air pressure of the tire 3 provided at each tire position from the sensor identifier and air pressure information included in the response signal and the sensor identifier table. Air pressure information for displaying the air pressure is output to the notification device 4. Based on the air pressure information output from the monitoring device 1, the notification device 4 displays the air pressure of each tire 3 on the indicator as a numerical value together with images of the vehicle C and the tire 3.

  When it is determined that response signals have not been received from some tire positions (step S12: NO), the control unit 11 calls a subroutine to perform update registration of the sensor identifier registered in the sensor identifier table (step S14). ), The process returns to step S11. In addition, after finishing update registration, you may comprise so that a 1st request signal may be transmitted only to the tire position of the tire 3 from which the air pressure information is not obtained.

  FIG. 6 is a flowchart showing a processing procedure of the monitoring apparatus 1 related to update registration of the sensor identifier. The control unit 11 that has called the subroutine in the process of step S14, except for the sensor identifier included in the received response signal, adds all the other stored in the storage unit 12 to the tire position where the response signal has not been received. It is determined whether or not a sensor identifier has been transmitted (step S31). When it is determined that there is an untransmitted sensor identifier (step S31: NO), other than the sensor identifier that has been transmitted to the tire position that has not received the response signal and the sensor identifier that is included in the received response signal, The second request signal including the sensor identifier is transmitted from the LF transmission antenna 14a at the tire position (step S32). And as a result of transmitting the 2nd demand signal by processing of Step S32, control part 11 judges whether a response signal was received from all four tire positions (Step S33). In addition, the control part 11 and the vehicle-mounted receiving part 13 which perform the process of step S33 function as a response signal receiving part which receives a response signal.

  When it determines with not having received the response signal from some tire positions (step S33: NO), the control part 11 returns a process to step S31. If it is determined that response signals have been received from all tire positions (step S33: YES), update registration of the sensor identifier registered in the sensor identifier table is performed (step S34), and processing of a subroutine related to update registration of the sensor identifier is performed. And the process returns to step S14. That is, the control unit 11 registers the sensor identifier included in the response signal transmitted from each tire position in the sensor identifier table in association with the tire position that is the transmission source of the sensor identifier.

  When it is determined that there is no untransmitted sensor identifier (step S31: YES), the control unit 11 includes a general-purpose identifier and a tire that has not received a response signal for the second request signal that requests transmission of the sensor identifier. Transmission is performed from the LF transmitting antenna 14a at the position (step S35). The format of the second request signal is not particularly limited. For example, the format is the same as that of the first request signal, and includes a predetermined general-purpose identifier instead of the sensor identifier. The general-purpose identifier is an identifier that can be commonly recognized by any detection device 2, and when a request signal including the general-purpose identifier is received, all the detection devices 2 transmit at least their own sensor identifiers. In addition, the second request signal may be a signal including a predetermined command for forcibly transmitting the sensor identifier. In addition, the control part 11 and the vehicle-mounted transmission part 14 which perform the process of step S35 function as a 2nd request signal transmission part which transmits a 2nd request signal.

  And the control part 11 determines whether the response signal transmitted from the detection apparatus 2 was received according to the 2nd request signal containing a general purpose identifier (step S36). As described later, when receiving the second request signal, the detection device 2 is configured to transmit a response signal including its own sensor identifier to the monitoring device 1 unless it is in the initial state. In addition, the control part 11 and the vehicle-mounted receiving part 13 which perform the process of step S36 function as a response signal receiving part which receives a response signal.

  When the control unit 11 of the monitoring device 1 determines that the response signal transmitted from the detection device 2 has been received (step S36: YES), the sensor received at the tire position where the detection device 2 that transmitted the response signal is located. An erasure signal including the identifier and erasing the initial state information is transmitted by the LF transmission antenna 14a (step S37). The erasure signal is a signal for confirming that information necessary for updating has been received. The control unit 11 and the in-vehicle transmission unit 14 that execute the process of step S37 function as an erasure signal transmission unit that transmits an erasure signal. And the control part 11 performs update registration of the sensor identifier registered into the sensor identifier table (step S38), complete | finishes the process of the subroutine which concerns on update registration of a sensor identifier, and returns a process to step S14. That is, the control unit 11 registers the sensor identifier included in the response signal transmitted from each tire position in the sensor identifier table in association with the tire position that is the transmission source of the sensor identifier. The control unit 11 that executes the process of step S38 functions as an update unit that associates and stores the tire position from which the second request signal is transmitted and the sensor identifier included in the response signal in the sensor storage unit 22. . When it is determined that the response signal is not received despite the transmission of the second request signal (step S36: NO), the control unit 11 provides abnormality information for notifying the abnormality of the tire pressure monitoring system. The information is output to the notification device 4 (step S39), the process of the subroutine relating to the update registration of the sensor identifier is finished, and the process returns to step S14. The notification device 4 displays the abnormality of the tire pressure monitoring system on the indicator based on the abnormality information output from the monitoring device 1.

  FIG. 7 is a flowchart showing a processing procedure of the detection apparatus 2. Since the operations of the four detection devices 2 are the same, the operation of the detection device 2 at the right front tire position will be described, and a detailed description of the other detection devices 2 will be omitted. The sensor control unit 21 of the detection device 2 monitors the reception state of various signals transmitted from the outside, and receives the LF band signal transmitted from the outside by the LF reception antenna 24a (step S51). For example, the sensor control unit 21 receives a first request signal, a second request signal, an erasure signal, and the like transmitted from the monitoring device 1 by the process of step S51. The sensor control unit 21 determines whether or not the received signal is a request signal, and the sensor identifier included in the request signal matches the sensor identifier stored in its own sensor storage unit 22 (step S52). ). If it is determined that it matches the sensor identifier of its own (step S52: YES), the sensor control unit 21 detects the air pressure by the air pressure detection unit 25 (step S53), and the air pressure information obtained by the detection, and its own sensor. A response signal including the identifier is transmitted to the monitoring apparatus 1 through the RF transmission antenna 23a (step S54), and the process is terminated.

  If it is determined that the sensor identifier does not match its own sensor identifier (step S52: NO), the sensor control unit 21 determines whether or not the received signal is a second request signal and includes a general-purpose identifier (step S55). ). Note that the sensor control unit 21 and the sensor reception unit 24 that execute the processes of step S51 and step S55 function as a request signal reception unit that receives the second request signal.

  When it determines with not containing a general purpose identifier (step S55: NO), the sensor control part 21 finishes a process.

  When it is determined that the universal identifier is included (step S55: YES), the sensor control unit 21 determines whether or not the sensor storage unit 22 is in the initial state in which the initial state information is stored (step S56). That is, it is determined whether or not its own sensor identifier is not registered in the sensor identifier table of the monitoring device 1. When it determines with it not being an initial state (step S56: NO), the sensor control part 21 finishes a process.

  When it determines with it being an initial state (step S56: YES), the sensor control part 21 transmits the response signal containing an own sensor identifier to the monitoring apparatus 1 with the RF transmission antenna 23a (step S57). The sensor control unit 21 and the sensor transmission unit 23 that execute the process of step S57 function as a response signal transmission unit that transmits a response signal.

  Next, after transmitting the response signal, the sensor control unit 21 determines whether or not an erasure signal including the same sensor identifier as its own sensor identifier has been received for a predetermined time (step S58). The sensor control unit 21 and the sensor reception unit 24 that execute the processes of step S51 and step S58 function as an erasure signal reception unit that receives an erasure signal.

  If it is determined that an erasure signal including the same sensor identifier as its own sensor identifier has not been received (step S58: NO), the sensor control unit 21 ends the process.

  When it is determined that an erase signal including the same sensor identifier as its own sensor identifier has been received (step S58: YES), the sensor control unit 21 erases the initial state information stored in the sensor storage unit 22 (step S59). ) Finish the process. The sensor control unit 21 that executes the process of step S59 functions as an erasing unit that erases the initial state information.

Next, the operation of the tire pressure monitoring system according to this embodiment will be described.
<Normal time>
FIG. 8 is a conceptual diagram showing a correspondence relationship between each tire position and the sensor identifier when the tire rotation and detection device 2 is not exchanged, and FIG. 9 is a diagram showing the tire rotation and detection device 2 exchanged. It is a chart which shows the processing contents when not.
As shown in FIG. 8, the sensor identifiers of the detection devices 2 at the right front, right rear, left rear, and left front tire positions are A, B, C, and D, respectively.
In FIG. 9, the “tire position” column indicates a tire position with which the monitoring device 1 communicates. The column “sensor identifier etc. transmitted from the monitoring device to the detection device” indicates the sensor identifier included in the first or second request signal transmitted from the monitoring device 1 to the detection device 2, or the first identifier transmitted in a specific situation. 2 shows a general identifier included in the second request signal. The “presence / absence of response signal transmitted from detection device to monitoring device” column indicates whether or not a response signal has been transmitted in response to the request signal transmitted to the tire position. “Present” indicates that a response signal has been transmitted, and characters in parentheses indicate sensor identifiers included in the response signal. The “registered sensor identifier” column indicates a sensor identifier registered in the sensor identifier table.

  When the sensor identifier table as shown in FIG. 3 is stored, the monitoring apparatus 1 includes first sensor identifiers A, B, C, and D at the right front, right rear, left rear, and left front tire positions, respectively. Send a request signal. In this case, as shown in FIG. 9, response signals are transmitted from all four tire positions. Accordingly, the monitoring device 1 monitors the air pressure without registering the sensor identifier table.

<At tire rotation>
FIG. 10 is a conceptual diagram showing the correspondence between each tire position when the tire rotation is performed and the sensor identifier, and FIG. 11 is a chart showing the processing contents when the tire rotation is performed. The upper diagram in FIG. 11 shows the state at the start of the update registration process, and the lower diagram in FIG. 11 shows the update registration process and its result. The “registered sensor identifier” column in the upper diagram of FIG. 11 indicates a sensor identifier that has been determined at the start of the update registration process, and the “registered sensor identifier” column in the lower diagram of FIG. Indicates a registered sensor identifier. The symbol “−” indicates that the sensor identifier is undefined.

  As shown in FIG. 10, the sensor identifiers of the detection device 2 at the right front, right rear, left rear, and left front tire positions are C, D, A, and B, respectively. When the sensor identifier table as shown in FIG. 3 is stored, the monitoring apparatus 1 includes first sensor identifiers A, B, C, and D at the right front, right rear, left rear, and left front tire positions, respectively. Send a request signal. In this case, as shown in the upper diagram of FIG. 11, response signals are not transmitted from all four tire positions.

  Therefore, the monitoring device 1 executes an update registration process for the sensor identifier table. Specifically, before transmitting the second request signal including the general-purpose identifier, the monitoring device 1 transmits the second request including the other sensor identifier B to the right front tire position as illustrated in the lower diagram of FIG. 11. Send a signal. Since the sensor identifier of the detection device 2 at the right front tire position is C, no response signal is returned in this case as well. Next, the monitoring device 1 transmits a second request signal including another sensor identifier C. In this case, since the sensor identifier C included in the second request signal matches the sensor identifier C of the detection device 2, a response signal is returned. The monitoring device 1 registers the sensor identifier C in association with the right front tire position.

  Similarly, the monitoring device 1 transmits a second request signal including the sensor identifier A, excluding the sensor identifier C of the received response signal and the sensor identifier B that has already been transmitted, to the right rear tire position. . Since the sensor identifier of the detection device 2 at the right rear tire position is D, no response signal is returned in this case as well. Next, the monitoring apparatus 1 transmits a second request signal including another sensor identifier D. In this case, since the sensor identifier D included in the second request signal matches the sensor identifier D of the detection device 2, a response signal is returned. The monitoring device 1 registers the sensor identifier D in association with the right rear tire position.

  Next, the monitoring device 1 transmits the second request signal including the sensor identifier A except the sensor identifiers C and D of the received response signal and the already transmitted sensor identifier C to the left rear tire position. To do. Since the sensor identifier of the detection device 2 at the left rear tire position is A, the sensor identifiers match and a response signal is returned. The monitoring device 1 registers the sensor identifier A in association with the left rear tire position.

  Further, the monitoring device 1 transmits the second request signal including the sensor identifier B excluding the sensor identifiers A, C, and D of the received response signal and the already transmitted sensor identifier D to the front left tire position. To do. Since the sensor identifier of the detection device 2 at the front left tire position is B, the sensor identifier matches and a response signal is returned. The monitoring device 1 registers the sensor identifier B in association with the front left tire position.

<When detecting device is replaced>
FIG. 12 is a conceptual diagram showing a correspondence relationship between each tire position and the sensor identifier when the detection device 2 is exchanged, and FIG. 13 shows processing contents when the detection device 2 is exchanged. It is a chart. As shown in FIG. 12, the sensor identifiers of the detection device 2 at the right front, right rear, left rear, and left front tire positions are E, B, C, and D, respectively. When the sensor identifier table as shown in FIG. 3 is stored, the monitoring apparatus 1 includes first sensor identifiers A, B, C, and D at the right front, right rear, left rear, and left front tire positions, respectively. Send a request signal. In this case, as shown in the upper diagram of FIG. 13, response signals are transmitted from all the tire positions other than the right front tire, but no response signals are transmitted from the right front tire position.
Therefore, the monitoring device 1 executes an update registration process for the sensor identifier table. Specifically, the monitoring device 1 has no sensor identifiers other than the sensor identifiers B, C, and D of the received response signal and the sensor identifier A that has already been transmitted. The monitoring apparatus 1 transmits a second request signal including the general-purpose identifier to the tire position on the right front. Since the second request signal includes a general-purpose identifier, the detection device 2 at the right front tire position unconditionally transmits a response signal including its own sensor identifier E. The monitoring device 1 registers the sensor identifier E included in the response signal in association with the right front tire position.

<Vehicle shipment>
FIG. 14 is a chart showing processing contents at the time of vehicle shipment in which the sensor identifier is not registered. At the time of vehicle shipment, a NULL sensor identifier is associated with all tire positions and registered in the sensor identifier table. Further, as shown in FIG. 8, the sensor identifiers of the detection devices 2 at the right front, right rear, left rear, and left front tire positions are A, B, C, and D, respectively.
As shown in the upper diagram of FIG. 14, the monitoring device 1 transmits first request signals each including a NULL sensor identifier to the right front, right rear, left rear, and left front tire positions. In this case, response signals are not transmitted from all four tire positions.
Therefore, the monitoring device 1 executes an update registration process for the sensor identifier table. Specifically, since there is no sensor identifier other than the sensor identifier of the received response signal and the already transmitted NULL sensor identifier, the monitoring device 1 includes a general-purpose identifier as shown in the lower diagram of FIG. A second request signal is transmitted to each tire position. Since the second request signal includes a general-purpose identifier and is in an initial state where its own sensor identifier is not registered in the monitoring device 1, the detection device 2 at each tire position includes its own sensor identifier unconditionally. Send a response signal. The monitoring apparatus 1 registers the sensor identifiers A, B, C, and D included in the response signal in association with the right front, right rear, left rear, and left front tire positions. When the sensor identifier of the newly installed detection device 2 is registered, even if the second request signal including the general-purpose identifier is transmitted from the monitoring device 1, the detection device 2 does not transmit a response signal. Therefore, since the detection device 2 does not silently transmit a response signal including the sensor identifier in response to the request signal including the general identifier, the possibility that the sensor identifier is erroneously registered in the monitoring device 1 can be reduced.

According to the tire pressure monitoring system according to the embodiment configured as described above, it is not necessary to register the sensor identifier of the detection device 2 in the monitoring device 1 in advance. Further, even when a new detection device 2 is provided on the tire 3 or when the tire 3 is replaced together with the detection device 2, the update registration process is executed, and the monitoring device 1 automatically detects each tire 3. The sensor identifier can be updated and registered.
In a situation where the detection device 2 is replaced at the time of shipment, even if the monitoring device 1 transmits the first request signal to each tire position, a response from the detection device 2 cannot be obtained. In this case, the content of the sensor identifier table may be different from the actual relationship between the tire position and the sensor identifier, and the content of the sensor identifier table needs to be updated. Therefore, the monitoring device 1 acquires the sensor identifier by transmitting the second request signal to the tire position having the problem, and updates the sensor identifier table using the acquired sensor identifier. Through the above processing, the monitoring device 1 can automatically update the sensor identifier table as necessary.

  In addition, the detection device 2 of this embodiment responds to the second request signal including the general-purpose identifier only when the sensor identifier of the detection device 2 is in an initial state that is not registered in the sensor identifier table of the monitoring device 1. Is transmitted to the monitoring device 1, and if it is not in the initial state, the response signal is not transmitted to the monitoring device 1. Therefore, a response signal corresponding to the second request signal is not unnecessarily transmitted from the detection device 2 to the monitoring device 1, and the sensor identifier table can be prevented from being erroneously updated.

  Furthermore, when the detection device 2 receives an erasure signal transmitted from the monitoring device 1 when a response signal is transmitted in response to the second request signal including the general-purpose identifier, the detection device 2 stores the initial state stored in the sensor storage unit 22. Erase information. More specifically, when receiving an erasing signal including the same sensor identifier as its own sensor identifier, the detection device 2 erases the initial state information. Therefore, the detection device 2 can delete the initial state information after confirming that its own sensor identifier is registered in the sensor identifier table. Therefore, it is possible to surely avoid a situation in which the initial state information is accidentally deleted and the monitoring apparatus 1 cannot update the sensor identifier due to the deletion of the initial state information.

Furthermore, since the monitoring device 1 according to the present embodiment is configured to update the sensor identifier table as necessary, the air pressure information of each tire 3 is promptly notified at an arbitrary timing, and as necessary. Update registration of the sensor identifier can be performed. For example, when the ignition switch 5 is switched from an off state to an on state, unnecessary update registration processing can be omitted and air pressure information of each tire 3 can be promptly notified. However, when the tire rotation is performed, the air pressure information of each tire 3 can be notified after updating and registering the sensor identifier.
Further, when the sensor identifier registered in the sensor identifier table and the sensor identifier of the detection device 2 at each tire position do not match, update registration processing of the sensor identifier is executed. Since the processing is not executed, unnecessary power consumption related to update registration can be suppressed.

  Furthermore, when the response signal is not returned in response to the transmission of the first request signal, the monitoring device 1 transmits a second request signal including a possible sensor identifier to the tire position. Therefore, the sensor identifier of the detection device 2 provided in the tire 3 at each tire position can be efficiently identified and the sensor identifier can be updated and registered.

  In the embodiment, the configuration has been described in which the air pressure information of each tire is notified when a response signal is transmitted from all tire positions. The air pressure information that has been made may be notified first, and then the sensor identifier of each tire position may be updated and registered.

Moreover, although the embodiment mainly related to the tire pressure monitoring system has been described, the hardware related to the wireless communication of the tire pressure monitoring system may also be used as another communication system. For example, the vehicle communication system of TPMS and passive entry system may be configured by sharing hardware related to wireless communication.
The passive entry system includes the monitoring device 1 and a portable device related to the passive entry system. The monitoring device 1 performs wireless communication with a portable device possessed by the user, authenticates the portable device, and detects the position of the portable device. A touch sensor (not shown) is provided on the door handle of the vehicle C. When the touch sensor detects that the user's hand has touched the door handle, or when the door switch is pressed, a regular portable device is provided. Is located outside the vehicle, the monitoring device 1 executes processing such as locking and unlocking the door of the vehicle C. When performing wireless communication with the portable device, the monitoring device 1 sets the transmission intensity of the signal transmitted from the LF transmission antenna 14a to be high, and transmits the request signal to the detection device 2 from the LF transmission antenna 14a. Set the transmission strength of the received signal low.
In addition, the passive entry system which comprises the communication system for vehicles is an example, and this invention can be applied to the system which performs wireless communication between a portable machine and the monitoring apparatus 1, and performs various vehicle control. For example, the communication system for a vehicle may constitute a push start system that enables starting of a prime mover mounted on the vehicle C without using a keyless entry system or a mechanical key together with TPMS.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Monitoring apparatus 2 Detection apparatus 3 Tire 4 Notification apparatus 5 Ignition switch 11 Control part 12 Memory | storage part 13 In-vehicle receiving part 13a RF receiving antenna 14 In-vehicle transmitting part 14a LF transmitting antenna 15 Timing part 16 In-vehicle communication part 17 Input part 21 Sensor control part Reference Signs List 22 Sensor storage unit 23 Sensor transmission unit 23a RF transmission antenna 24 Sensor reception unit 24a LF reception antenna 25 Air pressure detection unit 26 Timekeeping unit C Vehicle

Claims (5)

A tire provided with each of a plurality of tires of a vehicle, and a plurality of detection devices that detect the air pressure of the tires, and a monitoring device that performs wireless communication with the detection devices and monitors the air pressure of each tire An air pressure monitoring system,
The monitoring device
A storage unit that stores a plurality of tire positions in which the plurality of tires are provided, and identifiers of the detection devices provided in the tires of the plurality of tire positions, in association with each other;
A first request signal transmission unit for transmitting a first request signal for requesting arbitrary information, including the identifier stored in the storage unit in association with the tire position, to at least one tire position; Prepared,
The detection device includes:
A request signal receiving unit for receiving the first request signal;
A response signal transmission unit that transmits a response signal when the identifier included in the first request signal received by the request signal reception unit matches the identifier of the request signal reception unit;
Furthermore, the monitoring device comprises:
A response signal receiving unit that receives the response signal according to the first request signal;
A determination unit that determines whether or not a response signal transmitted from the detection device corresponding to the identifier included in the first request signal is received in response to the first request signal;
When it is determined that the response signal corresponding to the first request signal has not been received, at least the identifier is requested to the tire position where the response signal corresponding to the first request signal has not been transmitted. A second request signal transmission unit that transmits the request signal of 2;
The response signal transmission unit of the detection device is
When the request signal receiving unit receives the second request signal, a response signal including at least the identifier of the request signal is transmitted;
The monitoring device
When the response signal receiving unit receives the response signal corresponding to the second request signal, the tire position where the second request signal is transmitted is associated with the identifier included in the response signal A tire pressure monitoring system comprising: an updating unit that is stored in the storage unit. The detection device includes:
An initial state storage unit that stores initial state information indicating an initial state in which the identifier of itself is not stored in the storage unit of the monitoring device;
The response signal transmitter is
The tire pressure monitoring according to claim 1, wherein when the initial state information is stored in the initial state storage unit and the second request signal is received, the response signal including at least the identifier of the initial state storage unit is transmitted. system. The monitoring device
When receiving the response signal according to the second request signal, comprising: an erasure signal transmission unit that transmits the erasure signal for erasing the initial state information, including the received identifier.
The detection device includes:
An erasure signal receiver for receiving the erasure signal transmitted from the monitoring device;
The tire pressure monitoring system according to claim 2, further comprising: an erasure unit that erases the initial state information stored in the initial state storage unit when the erasure signal reception unit receives the erasure signal. A monitoring device that is provided in each of a plurality of tires of a vehicle, performs wireless communication with a plurality of detection devices that detect the air pressure of the tires, and monitors the air pressure of each tire,
A storage unit that stores a plurality of tire positions in which the plurality of tires are provided, and identifiers of the detection devices provided in the tires of the plurality of tire positions, in association with each other;
A first request signal transmission unit that transmits a first request signal that requests arbitrary information, including the identifier stored in the storage unit in association with the tire position, to at least one tire position;
A response signal receiving unit that receives the response signal according to the first request signal;
A determination unit that determines whether or not a response signal transmitted from the detection device corresponding to the identifier included in the first request signal is received in response to the first request signal;
When it is determined that the response signal corresponding to the first request signal has not been received, at least the identifier is requested to the tire position where the response signal corresponding to the first request signal has not been transmitted. A second request signal transmitter for transmitting two request signals;
The tire from which the second request signal is transmitted when the response signal receiving unit receives a response signal transmitted from the detection device in response to the second request signal and including the identifier of the detection device. A monitoring device comprising: an updating unit that associates a position with the identifier included in the response signal and stores the identifier in the storage unit. Detection that is provided on a tire of a vehicle and includes an identifier corresponding to its own identifier and wirelessly transmits a signal including the arbitrary information and its own identifier when receiving a first request signal requesting arbitrary information A device,
A request signal receiving unit that includes the identifier and receives a first request signal for requesting the air pressure information;
A response signal transmission unit that transmits a response signal when the identifier included in the first request signal received by the request signal reception unit matches the identifier of the request signal reception unit;
The response signal transmitter is
The detection device configured to transmit a response signal including at least the own identifier when the request signal receiving unit receives at least a second request signal requesting the identifier.

Images