JP2017065573A - Tire air pressure monitoring system and monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire air pressure monitoring system that can specify an identifier corresponding to each tire position and has high flexibility for arrangement of an antenna which receives air pressure signals of the tire.SOLUTION: The tire air pressure monitoring system comprises: a plurality of detection devices 2, provided in a plurality of tires 3 of a vehicle respectively, which transmit by radio air pressure signals including air pressure of the tires 3 and identifiers thereof; and a monitoring device 1 that receives the air pressure signals to monitor the air pressure of the tires 3. One of the detection device 2 transmits a first signal for specification including the identifier thereof. The other of the detection device 2 receives the first signal for specification, measures received signal intensity of the signal, and transmits a second signal for specification including the measured received signal intensity and the identifier thereof. The monitoring device 1 receives the first and second signals for specification by an antenna 13a eccentrically disposed on one tire position, measures received signal intensity of the signals, and specifies a correspondence relation between tire positions and the identifiers on the basis of the measured received signal intensity and the first and second signals for specification.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tire pressure monitoring system and a monitoring device.

  There is a tire pressure monitoring system (TPMS) that detects the air pressure of a tire attached to a vehicle and issues a warning to the user when the detected air pressure is abnormal. The tire pressure monitoring system detects a tire pressure, receives a pneumatic signal related to the detected pneumatic pressure wirelessly using a radio wave in the UHF band, and receives and receives a pneumatic pressure signal wirelessly transmitted from the detection device And a monitoring device that monitors the tire air pressure based on the air pressure signal. The detection device is provided in each of the right front, left front, right rear, and left rear tires, and wirelessly transmits a pneumatic signal including information on the detected pneumatic pressure and an identifier for identifying each detection device. The detection device, for example, periodically transmits an air pressure signal while the vehicle is traveling. The monitoring device is provided on the vehicle body, and receives the air pressure signal transmitted from each detection device. The monitoring device stores an identifier of a detection device provided in each tire in a memory in association with four tire positions where the tire is attached to the vehicle. The monitoring device can recognize the air pressure of the tire attached to each tire position by collating the identifier included in the received air pressure signal with the identifier stored in the memory.

  By the way, in order to make the wear state of the four tires uniform, tire rotation for exchanging the positions of the tires attached to the vehicle is generally performed. In addition, tire replacement may be performed. When the tire mounting position is changed, the monitoring device needs to update the correspondence relationship between the four tire positions and the identifiers.

  Patent Document 1 discloses a tire position determination system that can determine the tire position while simplifying the configuration and reducing the cost. The tire position determination system includes RF receiving antennas that are provided at different distances from each tire and receive an RF band signal wirelessly transmitted from a detection device at each tire position. The receiver unit connected to the RF receiving antenna determines the tire position where each detection device is provided from the received signal strength of the signal transmitted from each detection device.

JP 2013-123997 A

  However, in the tire position determination system according to Patent Document 1, it is necessary to provide an RF receiving antenna at a position where the distance from each tire is different, and there is a problem in that the degree of freedom of arrangement of the RF receiving antenna is low.

  An object of the present invention is to specify an identifier corresponding to each tire position, and has a high degree of freedom in arrangement of antennas for receiving signals transmitted from a detection device in order to specify the correspondence between tire positions and identifiers. A tire pressure monitoring system and a monitoring device are provided.

  A tire pressure monitoring system according to an aspect of the present invention is provided in each of a plurality of tires of a vehicle, detects a pressure of the tire, and wirelessly transmits a pressure signal including the detected pressure and its own identifier. A tire pressure monitoring system comprising: a detecting device for monitoring the air pressure of each tire by receiving the air pressure signal transmitted from the detecting device, wherein at least one of the detecting devices A first specifying signal transmitting unit that includes an identifier and transmits a first specifying signal for specifying a correspondence relationship between the plurality of tire positions and the identifiers of the plurality of detecting devices; A first specifying signal receiving unit that receives the first specifying signal transmitted from the one detection device, and a first specifying signal received by the first specifying signal receiving unit. A monitoring unit that measures a received signal strength; and a second specifying signal transmission unit that transmits a second specifying signal including the received signal strength measured by the measuring unit and the identifier of the received signal strength. The apparatus includes an antenna biased to any of a plurality of tire positions to which the plurality of tires are attached, the first specifying signal transmitted from the one detection device, and the first signal transmitted from the other detection device. A receiving unit that receives two identifying signals by the antenna, a measuring unit that measures received signal strengths of the first identifying signal and the second identifying signal received by the receiving unit, and the measuring unit The received signal strengths of the first specifying signal and the second specifying signal measured in the above, the identifier included in the first specifying signal, the identifier included in the second specifying signal, and the reception Based on signal strength Te, and a correspondence relationship specification unit for specifying a correspondence between the identifier of the plurality of tire locations and the plurality of detection devices.

  A monitoring device according to an aspect of the present invention is provided in each of a plurality of tires of a vehicle, detects a pressure of the tire, and detects a plurality of detections by wirelessly transmitting a detected air pressure and an air pressure signal including its own identifier. A monitoring device that receives the air pressure signal transmitted from a device and monitors the air pressure of each tire, the antenna biased to one of a plurality of tire positions to which the plurality of tires are attached, and the one detection device The first identifying signal transmitted from the one detecting device, the received signal strength of the first identifying signal and the identifier of the other detecting device, and the other detecting device. A receiving unit that receives the second specifying signal transmitted from the receiving unit, a measuring unit that measures the received signal strength of the first specifying signal and the second specifying signal received by the receiving unit, and the measuring unit The received signal strengths of the first specifying signal and the second specifying signal measured in the above, the identifier included in the first specifying signal, the identifier included in the second specifying signal, and the reception A correspondence relationship identifying unit that identifies correspondence relationships between the plurality of tire positions and the identifiers of the plurality of detection devices based on the signal intensity.

  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 tire pressure monitoring method using such characteristic processing as a step, or such a step as a computer. Or can be realized as a program to be executed. Moreover, it is realizable as a semiconductor integrated circuit which implement | achieves a part or all of a tire pressure monitoring system, or it can implement | achieve as other systems containing a tire pressure monitoring system.

  According to the above, a tire that can specify an identifier corresponding to each tire position and has a high degree of freedom in arrangement of an antenna that receives a signal transmitted from a detection device in order to specify the correspondence between the tire position and the identifier An air pressure monitoring system can be provided.

It is a mimetic diagram showing an example of 1 composition of a tire air pressure monitoring system concerning Embodiment 1 of the present 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 an 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 which concerns on registration of an identifier.

[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) A tire air pressure monitoring system according to an aspect of the present invention is provided in each of a plurality of tires of a vehicle, detects the air pressure of the tire, and wirelessly transmits a detected air pressure and an air pressure signal including its own identifier. A tire air pressure monitoring system comprising: a plurality of detecting devices that transmit; and a monitoring device that receives the air pressure signal transmitted from the detecting device and monitors the air pressure of each tire, wherein at least one of the detecting devices comprises: A first identifying signal transmitting unit that includes a first identifying signal that includes the identifier of the plurality of tires and identifies a correspondence relationship between the identifiers of the plurality of tire positions and the plurality of detection devices; The detecting device includes a first specifying signal receiving unit that receives the first specifying signal transmitted from the one detecting device, and the first specifying signal received by the first specifying signal receiving unit. A measuring unit for measuring the received signal strength of the signal, and a second specifying signal transmitting unit for transmitting a second specifying signal including the received signal strength measured by the measuring unit and the identifier of the receiver. The monitoring device is transmitted from an antenna biased to any of a plurality of tire positions to which the plurality of tires are attached, the first specifying signal transmitted from the one detection device, and the other detection device. A receiving unit that receives the second specifying signal by the antenna; a measuring unit that measures received signal strengths of the first specifying signal and the second specifying signal received by the receiving unit; and the measurement The received signal strengths of the first specifying signal and the second specifying signal measured by the unit, the identifier included in the first specifying signal, the identifier included in the second specifying signal, and The received signal strength and Based on, and a correspondence relationship specification unit for specifying a correspondence between the identifier of the plurality of tire locations and the plurality of detection devices.

In this aspect, one detection apparatus wirelessly transmits a first specifying signal including its own identifier at a predetermined timing. The first specifying signal needs to reach the monitoring device and all other detecting devices, and the first specifying signal is a radio signal that reaches a wide range.
The detection devices at other tire positions measure the received signal strength of the first specifying signal, and wirelessly transmit the second specifying signal including its own identifier together with the measured received signal strength.
The monitoring device receives the first specifying signal and the second specifying signal, and measures the received signal strengths of the first specifying signal and the second specifying signal in the measurement unit. Then, the monitoring device uses the measured received signal strengths of the first and second specifying signals, the identifier included in the first specifying signal, and the identifier and received signal strength included in the second specifying signal, for each tire. The correspondence between the identifier of the detection device provided in the tire at the position and the tire position is specified.
Although the relative positional relationship of the detection device that is the transmission source of the second specifying signal is specified by the received signal strength included in the second specifying signal, the correspondence between each identifier and the tire position is described later. The relationship is not uniquely determined. The received signal strength of the first and second specifying signals measured by the monitoring device can be said to be auxiliary information for uniquely determining the correspondence between each identifier and the tire position.
For this reason, the received signal strengths of the first and second specifying signals need not be such that the tire positions that are the transmission sources of the first and second specifying signals can be specified alone. That is, it is not necessary to arrange the antennas of the monitoring device so that the distances between the tire positions are different from each other. It is sufficient that the antenna of the monitoring device is biased to one of a plurality of tire positions to which a plurality of tires are attached. Therefore, the degree of freedom of antenna placement is high.

(2) The correspondence specifying unit specifies the identifier of the detection device at a predetermined tire position based on the received signal strengths of the first specifying signal and the second specifying signal. A positional relationship identifying unit that identifies relative positional relationships of the plurality of detection devices based on the received signal strength included in the second identifying signal, and the tires at other tire positions, respectively. The structure provided with the 2nd specific | specification part which specifies the said identifier of the said detected apparatus.

In this aspect, the specific unit detects the tire position where the antenna of the monitoring device is biased based on the received signal strengths of the first and second specifying signals measured by the measurement unit of the monitoring device. Identify the device identifier. Specifically, the specifying unit associates an identifier included in the first specifying signal or the second specifying signal having the strongest received signal strength with a predetermined tire position where the antenna is biased.
The plurality of tire positions are the front right, left front, right rear, and left rear of the vehicle, and generally the distance between the two tire positions in the lateral direction is shorter than the distance between the two tire positions in the vehicle traveling direction. For this reason, the received signal strengths included in the second specifying signal are different from each other, and from which tire position each second specifying signal is wirelessly transmitted can be specified from the magnitude of the received signal strength. The positional relationship specifying unit specifies the relative positional relationship of the plurality of detection devices based on the received signal strength included in the second received signal strength in this way. Since each tire position is symmetric in the longitudinal direction, the position of the detection device is not uniquely determined only by the received signal strength, but since the identifier of the detection device at the predetermined tire position where the antenna is biased has been determined, The tire position from which each second specifying signal is transmitted can be uniquely specified. The second specifying unit specifies the correspondence between the identifier included in the second specifying signal, that is, the identifier of the detection device that is the transmission source of the second specifying signal, and each tire position.

(3) It is preferable that the first specifying signal and the second specifying signal are UHF band radio signals.

In this aspect, the first and second specifying signals are UHF band radio signals. Since the radio signal of the UHF band has a higher frequency than the radio signal of the LF band or the like, it can be set shorter than the operation time of the first specifying signal receiving unit.
Therefore, the power consumption of the detection device can be more effectively suppressed.

(4) A monitoring device according to an aspect of the present invention is provided in each of a plurality of tires of a vehicle, detects the air pressure of the tire, and wirelessly transmits a detected air pressure and an air pressure signal including its own identifier. A monitoring device that receives the air pressure signals transmitted from a plurality of detection devices and monitors the air pressure of each tire, wherein the antenna is biased to one of a plurality of tire positions to which the plurality of tires are attached; Including the identifier of the detection device, including the first identification signal transmitted from the one detection device, the received signal strength of the first identification signal and the identifier of the other detection device, and the other A receiving unit that receives the second identifying signal transmitted from the detection device; a measuring unit that measures the received signal strength of the first identifying signal and the second identifying signal received by the receiving unit; The The received signal strengths of the first specifying signal and the second specifying signal measured by the fixing unit, the identifier included in the first specifying signal, and the identifier included in the second specifying signal And a correspondence relationship identifying unit that identifies the correspondence relationship between the plurality of tire positions and the identifiers of the plurality of detection devices based on the received signal strength.

  In this mode, as in mode (1), there is a high degree of freedom in arrangement of antennas that receive signals transmitted from the detection device in order to specify the correspondence between tire positions and identifiers, and this corresponds to each tire position. It is also possible to specify an identifier.

[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 a claim are included.

  FIG. 1 is a schematic 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 position of the vehicle body, a detection device 2 provided on each wheel of a tire 3 attached to the vehicle C, and a notification device 4. . The detection device 2 periodically detects the air pressure of the tire 3 under a predetermined condition such as traveling, and transmits an air pressure signal related to the detected air pressure to the monitoring device 1 by radio waves in a UHF (Ultra High Frequency) band. The monitoring device 1 includes an RF receiving antenna 13a, receives the air pressure signal transmitted from each detection device 2 by the RF receiving antenna 13a, and acquires information on the air pressure of each tire 3 from the air pressure signal. 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 information on the air pressure transmitted from the monitoring device 1 and notifies the air pressure 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, a received signal strength measuring unit 14, a time measuring unit 15, and an in-vehicle communication unit 16.

  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 received signal strength measuring unit 14, the time measuring unit 15, and the in-vehicle communication unit 16 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 an identifier registration process and a tire air pressure monitoring process, which will be described later, 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 communication processing and tire pressure monitoring processing by the control unit 11 controlling the operation of each component of the monitoring device 1. In addition, the storage unit 12 stores an identifier table that stores correspondence relationships between the four tire positions and identifiers that identify the detection devices 2 of the tires 3 attached to the respective tire positions.

  FIG. 3 is a conceptual diagram illustrating an example of an identifier table. The identifier table stores four tire positions and identifiers of the detection devices 2 provided on the tires 3 at the respective tire positions in association with each other. The four tire positions are positions where the front right, left front, right rear, and left rear tires 3 are attached. The distance between the two tire positions on the front left and right or the rear left and right of the vehicle is shorter than the distance between the two tire positions on the front right and rear or the left and right front of the vehicle.

An RF receiving antenna 13 a is connected to the in-vehicle receiving unit 13. The RF receiving antenna 13a is provided in a housing (not shown) of the monitoring device 1, and the housing of the monitoring device 1 is biased to a tire position, for example, a tire position on the right front side of the vehicle. The in-vehicle receiving unit 13 receives a signal transmitted from the detection device 2 using radio waves in the UHF band 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 receiving unit 13 is provided with a received signal strength measuring unit 14 that measures the received signal strength of the signal received by the in-vehicle receiving unit 13 and outputs the measured received signal strength to the sensor control unit 21. ing.

  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 the air pressure of each tire 3 provided in the vehicle C.

  FIG. 4 is a block diagram illustrating a configuration example of the detection device 2. Since the configuration of the four detection devices 2 is the same, the configuration of one detection device 2 will be described below. The detection device 2 includes a sensor control unit 21 that controls the operation of each component of the detection device 2. Connected to the sensor control unit 21 are a sensor storage unit 22, a sensor transmission / reception unit 23, a received signal strength measurement unit 24, an air pressure detection unit 25, and a timer unit 26.

  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 / reception unit 23, the received signal strength measurement 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.

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 acquires the air pressure of the tire 3 from the air pressure detection unit 25 by executing a control program, generates an air pressure signal including information such as the air pressure and an identifier unique to the detection device 2, and transmits and receives the sensor. To the unit 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 an air pressure signal including information such as air pressure, temperature, and an identifier, and outputs the air pressure signal to the sensor control unit 21.

An RF transmission / reception antenna 23 a is connected to the sensor transmission / reception unit 23. The sensor transmission / reception unit 23 modulates the air pressure signal generated by the sensor control unit 21 into a UHF band signal, and transmits the modulated air pressure signal using the RF transmission / reception antenna 23a. The directivity of the RF transmitting / receiving antenna 23a is not particularly limited, but a configuration facing the inside of the vehicle is preferable. The sensor transmission / reception unit 23 is also a circuit that demodulates a UHF band signal received by the RF transmission / reception antenna 23 a and outputs the demodulated signal to the sensor control unit 21.
The sensor transmission / reception unit 23 is provided with a reception signal strength measurement unit 24 that measures the reception signal strength of the signal received by the sensor transmission / reception unit 23 and outputs the measured reception signal strength to the sensor control unit 21.
In particular, in the present embodiment, the sensor transmission / reception unit 23 includes a first identifier having its own identifier as information for specifying a correspondence relationship between a plurality of tire positions and identifiers at a predetermined timing according to the control of the sensor control unit 21. A signal for identification is transmitted by radio. In addition, when the first identification signal transmitted from the other detection device 2 is received by the RF transmission / reception antenna 23a, the signal is obtained by measurement by the reception signal strength measurement unit 24 under the control of the sensor control unit 21. A second specifying signal including the received signal strength of the first specifying signal and its own identifier is wirelessly transmitted.
Details of the process of specifying the correspondence between the identifier and the tire position using the first and second specifying signals will be described later.

Next, an identifier registration process procedure will be described.
FIG. 5 is a flowchart showing a processing procedure related to registration of an identifier. The sensor control unit 21 of one detection device 2 transmits a first specifying signal including its own identifier through the RF transmission / reception antenna 23a (step S11). Here, an example in which the detection device 2 provided on the tire 3 at the right front tire position wirelessly transmits the first specifying signal will be described. Hereinafter, the detection device 2 that has transmitted the first identification signal is referred to as one detection device 2. The first specifying signal is wirelessly transmitted to the monitoring device 1 and the other detection device 2. The other detection devices 2 are the three detection devices 2 provided on the tire 3 at the tire positions at the left front, right rear, and left rear of the vehicle.

  The control unit 11 of the monitoring device 1 receives the first specifying signal transmitted from the one detecting device 2 by the RF receiving antenna 13a (step S12), and the received signal strength of the first specifying signal is received signal strength. Measurement is performed by the measurement unit 14 (step S13).

  On the other hand, the sensor control unit 21 of the other detection device 2 receives the first specifying signal transmitted from the one detection device 2 by the RF transmission / reception antenna 23a (step S14). Then, the sensor control unit 21 measures the received signal strength of the received second specifying signal at the received signal strength measuring unit 24 (step S15). And the sensor control part 21 transmits the signal for 2nd specification containing the received signal strength obtained by the measurement, and its own identifier with the RF transmission / reception antenna 23a (step S16). The second specifying signal is wirelessly transmitted to the monitoring device 1.

  The control unit 11 of the monitoring device 1 receives the second specifying signal transmitted from the other detecting device 2 by the RF receiving antenna 13a (step S17), and measures the received signal strength of the second specifying signal (step S17). Step S18).

  Next, the control unit 11 specifies an identifier corresponding to the tire position in the vicinity of the RF receiving antenna 13a based on the received signal strengths of the first and second specifying signals obtained by the measurement by the first measuring unit. (Step S19). Specifically, the identifier included in the first specifying signal is associated with the right front tire position.

  Next, the control unit 11 specifies the relative positional relationship between the plurality of detection devices 2 based on the received signal strength included in the received second specifying signal (step S20). Since the distance between one tire position and the other three tire positions is different, by comparing a plurality of received signal strengths, which tire position each second received signal strength is a signal transmitted from Can be specified. For example, since the front left tire position has the shortest distance from the right front tire position, it can be seen that the second received signal strength having the maximum received signal strength is transmitted from the right front tire position. Similarly, since the left rear tire position has the longest distance from the right front tire position, it can be seen that the second received signal strength having the smallest received signal strength is transmitted from the left rear tire position. . In addition, since the right rear tire position has a medium distance from the right front tire position, the second received signal intensity having a medium received signal intensity is transmitted from the right rear tire position. I understand.

  And the control part 11 specifies the correspondence of the identifier each contained in three 2nd received signal strength, and another tire position (step S21). Specifically, the identifier corresponding to the front left, rear right, and rear left tire positions is specified. And the control part 11 registers the identifier of each specified tire position into an identifier table (step S22), and complete | finishes a process.

  According to the tire pressure monitoring system configured as described above, an identifier corresponding to each tire position can be specified. In addition, a tire pressure monitoring system with a high degree of freedom in arrangement of the monitoring device 1 and the RF receiving antenna 13a can be configured.

  Further, by transmitting and receiving an RF band signal without using an LF band signal, each tire position and the identifier of the detection device 2 can be associated with each other and registered in the identifier table. Furthermore, the monitoring device 1 can monitor the air pressure of each tire 3 by transmitting and receiving an air pressure signal in the RF band.

  In the above-described embodiment, the example in which the detection device 2 on the right front transmits the first specifying signal has been described. However, when the other detecting device 2 transmits the first specifying signal, each tire is similarly processed. The position and the identifier can be associated with each other and registered in the identifier table. For example, each of the plurality of detection devices 2 may be configured to transmit the first identification signal at random timing so that the first identification signal is not transmitted simultaneously.

DESCRIPTION OF SYMBOLS 1 Monitoring apparatus 2 Detection apparatus 3 Tire 4 Notification apparatus 11 Control part 12 Storage part 13 Car-mounted receiving part 13a RF receiving antenna 14 Received signal strength measurement part 15 Time measuring part 16 In-vehicle communication part 21 Sensor control part 22 Sensor storage part 23 Sensor transmission / reception Unit 23a RF transmission / reception antenna 24 received signal strength measurement unit 25 air pressure detection unit 26 timing unit C

Claims (4)

A plurality of detection devices that are respectively provided on a plurality of tires of a vehicle, detect the air pressure of the tires, and wirelessly transmit a detected air pressure and an air pressure signal including its own identifier; A tire pressure monitoring system comprising: a monitoring device that receives a pressure signal and monitors the pressure of each tire;
At least one of the detection devices is
Including a first specifying signal transmission unit that includes a first specifying signal for specifying a correspondence relationship between the identifiers of the plurality of tire positions and the plurality of detection devices, including the identifier of the device;
The other detection devices are:
A first specifying signal receiving unit that receives the first specifying signal transmitted from the one detection device;
A measuring unit for measuring the received signal strength of the first specifying signal received by the first specifying signal receiving unit;
A second specifying signal transmitting unit that transmits a second specifying signal including the received signal strength measured by the measuring unit and the identifier of the received signal strength;
The monitoring device
An antenna biased to any of a plurality of tire positions to which the plurality of tires are attached;
A receiving unit that receives the first specifying signal transmitted from the one detecting device and the second specifying signal transmitted from the other detecting device by the antenna;
A measuring unit for measuring received signal strengths of the first specifying signal and the second specifying signal received by the receiving unit;
The received signal strengths of the first specifying signal and the second specifying signal measured by the measuring unit, the identifier included in the first specifying signal, and the second specifying signal included in the second specifying signal. A tire pressure monitoring system comprising: a correspondence specifying unit that specifies a correspondence between the plurality of tire positions and the identifiers of the plurality of detection devices based on an identifier and the received signal strength. The correspondence specifying unit
A first identifying unit that identifies the identifier of the detection device at a predetermined tire position based on the received signal strength of the first identifying signal and the second identifying signal;
A positional relationship identifying unit that identifies relative positional relationships of the plurality of detection devices based on the received signal strength included in the second identifying signal;
The tire pressure monitoring system according to claim 1, further comprising: a second specifying unit that specifies the identifier of the detection device provided in each of the tires at other tire positions. The tire pressure monitoring system according to claim 1 or 2, wherein the first specifying signal and the second specifying signal are UHF band radio signals. It is provided in each of a plurality of tires of a vehicle, receives the air pressure signals transmitted from a plurality of detection devices that detect the air pressure of the tires and wirelessly transmit the air pressure signals including the detected air pressure and its own identifier. Monitoring device for monitoring the air pressure of each tire,
An antenna biased to any of a plurality of tire positions to which the plurality of tires are attached;
The first identifying signal transmitted from the one detecting device, the received signal strength of the first identifying signal and the identifier of the other detecting device, A receiving unit for receiving a second identifying signal transmitted from another detection device;
A measuring unit for measuring received signal strengths of the first specifying signal and the second specifying signal received by the receiving unit;
The received signal strengths of the first specifying signal and the second specifying signal measured by the measuring unit, the identifier included in the first specifying signal, and the second specifying signal included in the second specifying signal. A monitoring device comprising: a correspondence specifying unit that specifies a correspondence between the identifiers of the plurality of tire positions and the plurality of detection devices based on an identifier and the received signal strength.

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