JP2003118333A - Tire pneumatic pressure monitoring device for vehicle and monitor device in the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire pneumatic pressure monitoring device for a vehicle capable of easily and securely detecting an abnormal condition and an abnormal section of a tire for the vehicle. SOLUTION: A microcomputer 17 switches a possibility and an impossibility for receiving a radio signal of reception antennas 13a to 13d when the reception antennas 13a to 13d receive the radio signal to monitor reception intensity of each reception antenna 13a to 13d. The microcomputer 17 specifies sensor devices 11a to 11d transmitting radio signals based on the reception intensity. Moreover, it judges an abnormality of tires 3a to 3d corresponding to the specified sensor devices 11a to 11d based on tire information included in the received radio signal. As a result, the microcomputer 17 displays that the tire information in the radio signal indicates an abnormal condition in a display device 15 if the tire information indicates the abnormal condition and displays in which tire of 3a to 3d an abnormality occurs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle tire pressure monitoring device for monitoring at least the air pressure of a vehicle tire and a monitoring device therefor.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, for example, a vehicle tire pressure monitoring device 51 includes a tire 53 of a vehicle 52.
The tire valves a to 53d are provided with sensor devices 54a to 54d, respectively.

The sensor devices 54a to 54d are adapted to detect tire information such as air pressure and temperature of the corresponding tires 53a to 53d, convert the tire information into radio signals and transmit them to the outside. In the vehicle 52, reception antennas 55a to 55d are arranged near the tires 53a to 53d, respectively. Therefore, the wireless signals transmitted from the sensor devices 54a to 54d are received by the corresponding receiving antennas 55a to 55d.

A receiving device 58 including a receiving circuit 56 and a microcomputer 57 is arranged in the vehicle 53, and radio signals received by the receiving antennas 55a to 55d are input to the receiving circuit 56. Then, the radio signal is demodulated into a pulse signal by the receiving circuit 56 and input to the microcomputer 57. The microcomputer 57 reads tire information based on the pulse signal. And
From the tire information, the microcomputer 57 determines the tires 53a-5
When it is determined that there is an abnormality in the air pressure or temperature of 3d, the indicator 5 provided on the instrument panel or the like
9 is activated and the passenger is informed accordingly.

For this reason, the passengers need to check the tires 53a to 53d.
It is possible to quickly and surely recognize that an abnormality has occurred in the. Therefore, it is possible to prevent abnormal wear of the tires 53a to 53d and improve the safety of the vehicle 52.

[0006]

[Problems to be Solved by the Invention] However, the microcomputer 5
No. 7 cannot determine which of the antennas 55a to 55d has received the radio signal, and therefore cannot determine which of the tires 53a to 53d has an abnormality.

Therefore, in order to eliminate such an inconvenience, conventionally, an individual ID code is set to each of the sensor devices 54a to 54d and the ID code is included in the wireless signal, and the ID code is stored in the microcomputer 57. It has been proposed to register it as information (Japanese Patent Laid-Open No. 200-200200).
Approximately disclosed in Japanese Patent Publication No. 0-142044). Specifically, the ID code of the tire 53a mounted at the front right position is registered in the microcomputer 57 as "front right" position information. With this configuration, the microcomputer 57 receives the wireless signals from the sensor devices 54a to 54d and, based on the ID code included in the wireless signals, the tires 53a to 5a.
The position of 3d can be recognized.

However, when the tires 53a to 53d are replaced or when the tires 53a to 53d are rotated, it is necessary to re-register the tire position information based on the ID code of each tire 53a to 53d in the microcomputer 57. is there. That is, for example, when changing the tire 53a mounted at the front right position to the rear right position, it is necessary to re-register the ID code of the tire 53a from the "front right" position information as "rear right" position information in the microcomputer 57. is there. Therefore, the replacement work of the tires 53a to 53d is complicated, and if such registration work is neglected, there is a possibility that an erroneous display of an abnormal portion may occur.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle tire pressure monitoring device capable of easily and surely detecting an abnormal state and an abnormal portion of a vehicle tire, and a vehicle tire. It is an object of the present invention to provide a monitor device in a tire pressure monitoring device.

[0010]

In order to solve the above-mentioned problems, according to the invention as set forth in claim 1, a plurality of sensor devices individually provided on a plurality of tires of a vehicle, and a transmission from those sensor devices. In the tire pressure monitoring device for a vehicle, which receives a wireless signal to be received, and a monitor device that monitors at least the air pressure of the corresponding tire based on the wireless signal, each of the sensor devices corresponds to the corresponding tire. The tire information including at least air pressure information is detected, and the tire information is transmitted as a radio signal at a predetermined intermittent cycle, and the monitor device is provided near each of the sensor devices and transmitted from the corresponding sensor device. Multiple receiving antennas for receiving wireless signals and reception of each receiving antenna by switching the reception availability of those receiving antennas Of the tire corresponding to the sensor device based on the tire information included in the received wireless signal while determining the sensor device that is transmitting the wireless signal based on the received intensity. The gist is to include a determination unit that performs the determination, and at least a notification unit that notifies the passenger of an abnormal state of the tire.

According to a second aspect of the present invention, in the vehicle tire pressure monitoring device according to the first aspect, the determining means sets all of the receiving antennas in a receivable state and waits for the radio signal. When receiving the radio signal, the reception antenna receiving the radio signal is specified by sequentially switching so that only one of the reception antennas can be received at predetermined time intervals. The gist is to determine that the sensor device corresponding to the receiving antenna is transmitting the wireless signal.

According to the third aspect of the present invention, a wireless signal transmitted from a plurality of sensor devices individually provided to a plurality of tires of a vehicle is received, and at least tire pressure information included in the wireless signal is received. A monitor device in a vehicle tire air pressure monitoring device for monitoring at least tire air pressure based on the tire information, which is provided near each of the sensor devices and receives a radio signal transmitted from the corresponding sensor device. A plurality of receiving antennas, and switching reception availability of these receiving antennas to monitor the receiving intensity of each receiving antenna, determine the sensor device transmitting the wireless signal based on the receiving intensity, and receive the received wireless signal. Judgment means for judging abnormality of the tire corresponding to the sensor device based on the tire information included in the signal , And summarized in that and a notifying means for informing the passenger of the abnormal state of at least the tire.

The "action" of the present invention will be described below. According to the invention described in any one of claims 1 to 3, the monitor device monitors the reception intensity of each reception antenna by switching the reception availability of the reception antenna, and transmits the wireless signal based on the reception intensity. The determination means for determining is provided. Therefore, the monitor device can specify that the wireless signal is transmitted from the sensor device corresponding to the receiving antenna by specifying the receiving antenna having the highest receiving intensity. Therefore, if the tire information of the radio signal indicates an abnormal state, the monitor device
It can be determined that the tire provided with the sensor device has an abnormality. Therefore, it is possible to easily and surely detect the abnormal state and the abnormal portion of the tire.

According to the second aspect of the present invention, the determination means waits for a radio signal by setting all of the receiving antennas in a receivable state. Therefore, when a wireless signal is transmitted from the sensor device, the determination unit immediately starts the tire abnormality determination. Therefore, when an abnormality occurs in the tire, the fact is immediately notified to the passenger.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described in detail below with reference to FIGS. As shown in FIG. 1, the tire pressure monitoring device 1 includes sensor devices 11 a to 11 d integrally formed with tire valves of the tires 3 a to 3 d of a vehicle 2, and a monitor device 12 arranged in the vehicle 2. It has and.

The sensor devices 11a to 11d are adapted to detect tire information such as air pressure and temperature of the corresponding tires 3a to 3d, convert the tire information into a radio signal and transmit it to the outside. Also, as shown in FIG.
These sensor devices 11a to 11d have a predetermined intermittent cycle T.
1 transmits a wireless signal. In addition, in the present embodiment, the intermittent cycle T1 is set to about 10 minutes. Specifically, the intermittent cycle T1 is set to a random time of about 10 minutes, so that the transmission timings of the wireless signals of the sensor devices 11a to 11d are difficult to synchronize. The transmission time T2 of the wireless signal is about 300 m
is set to s. Further, as shown in FIG. 4, in the present embodiment, the sensor devices 11a to 11d are configured to transmit wireless signals in two types of data transmission patterns. Specifically, the sensor devices 11a to 11d transmit a wireless signal in the transmission pattern A when the detected air pressures and temperatures of the tires 3a to 3d have normal values, and when the air pressures and temperatures have abnormal values. Transmits a wireless signal in transmission pattern B. The transmission patterns A and B are composed of a combination of three types of data frames Dα, Dβ, Dγ including the ID codes of the sensor devices 11a to 11d, respectively. By the way, the data frames Dα and Dγ are ID
The data frame Dβ is composed of an ID code and detailed tire information.

As also shown in FIG. 2, the monitor device 12
Is a plurality of (here, four) receiving antennas 13a to 13
d, a receiver 14 and a display 15 as an informing means.

The receiving antennas 13a to 13d are connected to the vehicle 2
It is arranged in the vicinity of each of the tires 3a to 3d. That is, the receiving antennas 13a to 13d are provided corresponding to the sensor devices 11a to 11d, respectively. For this reason, the radio signals transmitted from the sensor devices 11a to 11d are transmitted to the corresponding receiving antennas 13a to 13d.
Received by.

The receiving device 14 comprises a receiving circuit 16 and a microcomputer 17 as a judging means. And each receiving antenna 13a-13d is
It is connected to the receiving circuit 16. The reception circuit 16 demodulates the radio signal received by the reception antennas 13 a to 13 d into a pulse signal and outputs the pulse signal to the microcomputer 17.
Further, the receiving circuit 16 has an RSSI (Received Signal St
rength Indicator: received signal strength display) circuit is built in, and the same receiving circuit 16 has each receiving antenna 13a to 13d.
The received signal strength display signal (RSSI signal) of the wireless signal is output to the microcomputer 17.

The microcomputer 17 is a C (not shown).
It is composed of a CPU unit including a PU, a ROM, and a RAM. Further, the microcomputer 17 is provided with the tire 3a.
Reference data such as air pressure and temperature of 3d are recorded in advance. The reference data is a value indicating a normal value such as the air pressure or temperature of the tires 3a to 3d, and is set within a predetermined range.

The display device 15 is provided in the interior of the vehicle 2 (for example, an instrument panel or the like), and is an indicator that indicates when an abnormality occurs in the tires 3a to 3d. The display 15 is connected to the microcomputer 17 and displays based on an operation signal from the microcomputer 17.

In the energizing paths between the receiving antennas 13a to 13d and the receiving circuit 16, the detecting units 18a to 18a are respectively provided.
18d is provided. These detectors 18a to 18d
Are respectively connected to the microcomputer 17, and the corresponding receiving antenna 1 based on the operation signal from the microcomputer 17.
It is adapted to control the reception propriety of 3a to 13d.
Specifically, as shown in FIG. 2, the detection units 18a to 18d are included.
Is composed of detection diodes D1 to D4 and resistors R1 to R4. More specifically, the first detection unit 18
a is composed of a detection diode D1 and a resistor R1, and the anode of the diode D1 and one end of the resistor R1 are connected to the first receiving antenna 13a. The cathode of the diode D1 is connected to the receiving circuit 16, and the other end of the resistor R1 is connected to the microcomputer 17. Also,
A resistor R is provided in the energization path between the diode D1 and the receiving circuit 16.
Is connected to one end and the other end of the resistor R is grounded.
The second detection unit 18b includes a detection diode D2 and a resistance R.
The second and third detection units 18c are each composed of a detection diode D3 and a resistor R3, and the fourth detection unit 18d is composed of a detection diode D4 and a resistor R4. These detectors 18b to 18d are configured similarly to the first detector 18a,
The anodes of the detection diodes D2 to D4 are connected to the corresponding receiving antennas 13b to 13d, and the cathodes are connected to the microcomputer 17, respectively. Also, each resistor R2
One end of each of R4 to R4 is connected to the anode of the corresponding diode D2 to D4, and the other ends thereof are individually connected to the microcomputer 17.

Accordingly, the detection unit 18a from the microcomputer 17 is detected.
When an H-level operation signal is output to ~ 18d,
A voltage is applied to the anodes of the detection diodes D1 to D4. Each of the detection diodes D1 to D4 has a low internal impedance when a voltage is applied to the anode and a high internal impedance when no voltage is applied to the anode. Therefore, the receiving antennas 13a to 13d are connected to the detection units 18a to 18d from the microcomputer 17.
When the H-level actuation signal is output to 18d, the receiving sensitivity becomes high, and the wireless signal can be preferably received. On the other hand, the receiving antennas 13a to 13d
Is L from the microcomputer 17 to the detection units 18a to 18d.
When the level operation signal is being output, the receiving sensitivity becomes low and it becomes difficult to receive the wireless signal.

Next, the abnormality determination processing of the tires 3a to 3d performed by the microcomputer 17 will be described. First, the microcomputer 17 performs a radio signal reception determination process.
In this process, the microcomputer 17 displays the point P1 in FIG.
As shown by, the H level operation signal is output to all of the detection units 18a to 18d. That is, the microcomputer 1
Reference numeral 7 enables all of the receiving antennas 13a to 13d to be in a standby state for wireless signals. When the receiving antennas 13a to 13d receive a radio signal in this standby state, a high-value RSSI signal is input to the microcomputer 17 from the receiving circuit 16. And that high value RSS
When the I signal is input to the microcomputer 17, point P
1 and P2, the microcomputer 17 determines that the predetermined time t1
Until all the time elapses, all the receiving antennas 13a to 13d are maintained in a receivable state. Then, the microcomputer 17
The antenna identification process is performed when the predetermined time t1 has elapsed. That is, the microcomputer 17 determines that the wireless signal is received by any of the receiving antennas 13a to 13d based on the RSSI signal, and shifts to the subsequent antenna identification processing. In the present embodiment, the predetermined time t1
Is set to about 30 ms.

In the antenna specifying process, the microcomputer 17
Outputs an operating signal of H level to only the first receiving antenna 13a, as indicated by a point P2 in FIG. In other words, the microcomputer 17 uses the other receiving antenna 13
L-level operation signals are output to b to 13d.
Then, after the elapse of the predetermined time t2, the microcomputer 17 switches the output of the H-level operation signal from the first reception antenna 13a to the second reception antenna 13b, as indicated by a point P3. Next, the microcomputer 17 sets points P4 and P
As shown by 5, each time the predetermined time t2 elapses, the output of the H-level actuation signal is sequentially switched to the third reception antenna 13c and the fourth reception antenna 13d.

Therefore, only the first receiving antenna 13a can be received between the points P2 and P3, and only the second receiving antenna 13b can be received between the points P3 and P4. Also, point P
Between the point 4 and the point P5, only the third receiving antenna 13c can receive, and only the fourth receiving antenna 13d can receive until the time point (point P6) after the predetermined time t2 has passed from the point P5. Therefore, for example, when the wireless signal is transmitted from the first sensor device 11a,
When the receiving antenna 13a is made receivable, the microcomputer 1
The RSSI signal having a higher value than that of 7 is input. On the other hand, when the other receiving antennas 13b to 13d can be received, the value of the RSSI signal becomes low. Therefore, the microcomputer 17 can specify that the first sensor device 11a is transmitting the wireless signal by monitoring the value of the RSSI signal. In addition, in this embodiment, the predetermined time t2 is set to about 25 ms. Further, in the antenna identifying process, when the microcomputer 17 determines that the plurality of sensor devices 11a to 11d are transmitting wireless signals, the microcomputer 17 performs the reception determining process again. On the other hand, the microcomputer 17 uses the single sensor device 11a-11a.
If it is determined that d is transmitting a wireless signal, abnormality determination processing is performed.

In the abnormality determining process, the microcomputer 17 determines each receiving antenna 13a as shown by point P6 in FIG.
Outputs an H level actuation signal for all of ~ 13d,
The receiving antennas 13a to 13d are made receivable. As shown in the figure, the output time of the H-level actuation signal in this abnormality determination processing is set to a predetermined time t3. The total time Σt from the start of the reception determination process (point P1) to the end of the predetermined time t3 (point P7) is set to be longer than the transmission time T2 of the wireless signal. In the present embodiment, the predetermined time t3 is set to about 200 ms. That is, the total time Σt is set to about 330 ms.

The radio signal transmitted during the predetermined time t3 is demodulated by the receiving circuit 16, and the tire information contained in the signal is input to the microcomputer 17. The microcomputer 17 determines the tires 3a to 3 based on this tire information.
It is determined whether or not the air pressure of d is abnormal. Specifically, the microcomputer 17 reads at least two data frames Dβ included in the wireless signal. Then, the microcomputer 17 compares the tire information of the data frame Dβ with the reference data preset in itself. Accordingly, the microcomputer 17 causes the tires 3a to 3 corresponding to the sensor devices 11a to 11d that have transmitted the wireless signal if the tire information of the data frame Dβ is within the range of the reference data.
It is determined that d is normal. If the tire information of the data frame Dβ is outside the range of the reference data, the microcomputer 17 sends the wireless signal to the sensor devices 11a to 11a.
It is determined that the tires 3a to 3d corresponding to 11d have an abnormality. Then, the microcomputer 17 uses the tires 3a to 3
When it is determined that there is an abnormality in d, an operation signal is output to the display unit 15 to display that there is an abnormality in the tires 3a to 3d, and which tire 3a to 3d.
Display whether there is an abnormality in d. It should be noted that the microcomputer 17 shifts to the reception determination processing again after finishing the abnormality determination processing, and repeats the series of processing described above.

Therefore, according to this embodiment, the following effects can be obtained. (1) When the wireless signal transmitted from the sensor devices 11a to 11d is received by the receiving antennas 13a to 13d, the microcomputer 17 switches the reception availability of each of the receiving antennas 13a to 13d to receive each of the receiving antennas 13a to 13d. Monitor intensity. Therefore, the microcomputer 17 can individually monitor the reception intensity of each of the reception antennas 13a to 13d. Therefore, by identifying the receiving antennas 13a to 13d having the highest receiving intensity, the microcomputer 17 can identify that the wireless signal is transmitted from the sensor devices 11a to 11d corresponding to the receiving antennas 13a to 13d. . Further, when the tire information of the wireless signal indicates an abnormal state, the microcomputer 17 causes the display unit 15 to display that fact and indicates which tire 3
It is displayed whether or not an abnormality has occurred in a to 3d. Therefore, it is possible to easily and surely detect the abnormal state and the abnormal portion of the tires 3a to 3d. Also, tires 3a to 3
It is possible to make the passenger easily and surely recognize the abnormal state and the abnormal portion of d.

(2) The microcomputer 17 uses the receiving antennas 1
All the signals 3a to 13d are set in a receivable state to wait for a wireless signal (reception determination processing). And microcomputer 1
When wireless signals are transmitted from the sensor devices 11a to 11d, 7 immediately starts the antenna identifying process and the abnormality determining process. Therefore, when an abnormality occurs in the tires 3a to 3d, the fact can be immediately notified to the passenger.

(3) When the microcomputer 17 determines in the antenna identifying process that the plurality of sensor devices 11a to 11d are transmitting radio signals, the microcomputer 17 performs the reception determining process again. That is, in this case, the microcomputer 17 does not perform the abnormality determination process. The microcomputer 17
When a plurality of wireless signals are received at the same time, the tire information included in the wireless signals cannot be associated with the sensor devices 11a to 11d. Therefore, the microcomputer 17 cannot determine which tire 3a to 3d has an abnormality even if the abnormality determination process is performed to determine the abnormality of the tires 3a to 3d in such a case. Therefore, by omitting the abnormality determination process in such a case, the passenger can be notified only when the abnormal state and the abnormal portion of the tires 3a to 3d are surely recognized.
In other words, it is possible to prevent the passenger from being notified of the ambiguous abnormality determination result.

(4) The microcomputer 17 in the abnormality determination processing
Makes all of the receiving antennas 13a to 13d receivable. For this reason, the microcomputer 17 can directly proceed to the reception determination process without switching the operation signal to each of the receiving antennas 13a to 13d after finishing the abnormality determination process. Therefore, the control program of the microcomputer 17 can be simplified.

The embodiment of the present invention may be modified as follows. In the above-described embodiment, the microcomputer 17 enables all of the receiving antennas 13a to 13d in the abnormality determination process. However, the microcomputer 17
Is a receiving antenna 1 which is identified as receiving a wireless signal.
Only 3a to 13d may be receivable. By doing so, it is possible to reduce the probability that noise and the like are mixed in the wireless signal, and the microcomputer 17 can read the tire information more reliably.

The microcomputer 17 in the above embodiment
Performs reception determination processing. However, the microcomputer 17 repeats the antenna identification processing without performing the reception determination processing, and shifts to the abnormality determination processing when the sensor devices 11a to 11d transmitting the wireless signal can be identified. Good. Even in this case, the microcomputer 17 can perform the reception determination and the antenna identification at the same time when the receiving antennas 13a to 13d receive the radio signal by repeatedly performing the antenna identification processing.

The number of sensor devices 11a to 11d is not limited to four, and may be increased or decreased according to the number of tires 3a to 3d of the vehicle 2. Moreover, the sensor devices 11a to 11d may not be provided on all the tires 3a to 3d of the vehicle 2. That is, the sensor devices 11a to 11d may be provided on at least two of the tires 3a to 3d. The receiving antennas 13a to 13d may be increased or decreased depending on the number of sensor devices 11a to 11d.

The microcomputer 17 in the above embodiment
Operates the indicator 15 only when the tires 3a to 3d are abnormal. However, the microcomputer 17 may operate the display unit 15 to notify the passenger even when no abnormality occurs in the tires 3a to 3d.

In the above embodiment, the display 15 is used as the notification means. However, the notifying means may be configured by a speaker and may notify the abnormal state of the tires 3a to 3d by voice.

Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the above-described embodiment will be listed below. (1) In the vehicle tire pressure monitoring device according to claim 2, when the determination unit determines that wireless signals are being transmitted from a plurality of sensor devices at the time of the determination of the sensor device, the wireless signals are transmitted. Without waiting for the abnormality of the tire based on the above, and again waiting for the radio signal by making all of the receiving antennas receivable. According to the invention described in this technical idea (1), it is possible to prevent the passenger from being notified of the ambiguous abnormality determination result.

(2) A plurality of sensor devices individually provided on a plurality of tires of a vehicle, and wireless signals transmitted from these sensor devices are received, and tires corresponding to the respective sensor devices based on the wireless signals. In at least an air pressure monitoring method for a vehicle tire air pressure monitoring device comprising a monitor device for monitoring air pressure,
The reception strength of each reception antenna is switched by switching the reception availability of the reception antenna provided near each of the sensor devices, and the sensor device transmitting the wireless signal is determined based on the reception strength, An abnormality determination of a tire corresponding to the sensor device is performed based on the tire information included in the received wireless signal, and at least when it is determined that the tire is abnormal, the passenger is notified of that fact.

[0040]

As described in detail above, according to the invention described in claims 1 to 3, the passenger can easily and surely recognize the abnormal state and the abnormal portion of the tire.

According to the second aspect of the present invention, when an abnormality occurs in the tire, the passenger can be immediately notified of that fact.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a vehicle provided with a vehicle tire pressure monitoring device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a monitor device of the same embodiment.

FIG. 3 is a time chart showing the transmission timing of a wireless signal transmitted from each sensor device of the same embodiment.

FIG. 4 is a time chart showing a monitoring aspect of the monitor device of the same embodiment.

FIG. 5 is a schematic plan view of a vehicle provided with a conventional vehicle tire pressure monitoring device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vehicle tire pressure monitoring device, 2 ... Vehicle, 3a to 3
d ... Tire, 11a-11d ... Sensor device, 12 ... Monitor device, 13a-13d ... Reception antenna, 15 ... Display device as notification means, 17 ... Microcomputer (microcomputer) as decision means, 18a-18d ... Detection unit .

Claims (3)

[Claims] 1. A plurality of sensor devices individually provided on a plurality of tires of a vehicle, and wireless signals transmitted from these sensor devices are received, and the tires corresponding to the respective sensor devices are received based on the wireless signals. In a vehicle tire air pressure monitoring device including at least a monitoring device for monitoring air pressure, each sensor device detects tire information including at least air pressure information of the corresponding tire, and the tire information is predetermined as a wireless signal. Transmitting at an intermittent cycle, the monitor device is provided in the vicinity of each of the sensor devices, and a plurality of receiving antennas for receiving wireless signals transmitted from the corresponding sensor devices, and switching between reception availability of these receiving antennas. A sensor that monitors the reception intensity of each reception antenna and transmits the radio signal based on the reception intensity A determination means for determining the device and performing an abnormality determination of the tire corresponding to the sensor device based on the tire information included in the received wireless signal, and at least an informing means for informing a passenger of an abnormal state of the tire. A tire pressure monitoring device for a vehicle, comprising: 2. The determining means waits for the radio signal with all the reception antennas in a receivable state, and at the time of receiving the radio signal, one of the reception antennas is received. The reception antenna receiving the radio signal is specified by sequentially switching so that only one reception antenna can receive the radio signal, and it is determined that the sensor device corresponding to the reception antenna is transmitting the radio signal. The vehicle tire pressure monitoring device according to claim 1. 3. A radio signal transmitted from a plurality of sensor devices individually provided to a plurality of tires of a vehicle is received, and based on the tire information having at least tire pressure information included in the radio signal, A monitor device in a tire pressure monitoring device for a vehicle for monitoring at least tire pressure, each of which is provided in the vicinity of each of the sensor devices, and has a plurality of receiving antennas for receiving a radio signal transmitted from a corresponding sensor device, The reception intensity of each reception antenna is switched to monitor the reception intensity of each reception antenna, the sensor device transmitting the radio signal is determined based on the reception intensity, and the tire information included in the received radio signal is determined. Determination means for determining abnormality of the tire corresponding to the sensor device based on A monitor device in a tire pressure monitoring device for a vehicle, comprising: an informing unit for informing a passenger of a normal state.