JP2005178699A - Assist device for signal transmission and reception, and tire air pressure drop alarming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an assist device for signal transmission and reception and a tire air pressure drop alarming device, capable of reducing the unit cost per vehicle and managing well with a relocation. <P>SOLUTION: The tire air pressure drop alarming device 1 is equipped with a transmitter unit 2 installed on each tire T and one receiver unit 3 to receive on the vehicle body side the signals transmitted from the transmitter units 2. The assist device 4 for signal transmission and reception is equipped with external reception units 5 installed in the neighborhood of the respective transmitter units 2 on the vehicle M side and an external transmission unit 6 installed in the neighborhood of the receiver unit 3 on the vehicle M side for transmitting thereto the signals emitted from the external reception units 5. The external reception unit 5 and the external transmission units 6 are installed outside of the vehicle M. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a tire pressure drop warning device for detecting tire puncture at an early stage, and more particularly to a transmission / reception assist device that assists communication between a transmitter provided on a tire and a receiver provided on a vehicle body side.

  Conventionally, as a device for detecting tire puncture at an early stage, for example, a pressure sensor for detecting the air pressure of each tire, and information on the air pressure of each tire can be reported to the driver based on a signal output from each pressure sensor. There is a tire pressure drop warning device mainly composed of an ECU for the purpose. In such a device, since it is necessary to perform wireless communication between the pressure sensor provided on each tire and the ECU provided on the vehicle body side, a transmission antenna is provided on each tire, and a reception antenna is provided on the vehicle body side. Is provided. And the following two techniques are disclosed as a tire pressure drop alarm device that performs wireless communication through such an antenna.

  The first technique is a technique that allows good communication between the transmitting antenna provided in each tire and the receiving antenna provided in each fender by providing a receiving antenna in each fender covering each tire ( Patent Document 1). In this technique, since a receiving antenna is provided for each tire, the ECU only recognizes from which receiving antenna the signal is sent, and the tire has a unique identification code (ID: Identification). Regardless, it is possible to know which tire pressure the signal indicates. Therefore, even at the time of rotation such as tire reassembly, tire replacement, pressure sensor replacement, etc., the ECU can recognize the position of the tire by automatically performing the alignment (relocation) of each ID and each position thereafter. It is possible.

  The second technique is a technique that can reduce the cost by providing only one receiving antenna at a transmitting position provided in each tire and a position where transmission is possible (substantially in the center of the vehicle) (Patent Document). 2). In this technique, since the ECU determines the position of the tire according to the ID of each tire, for example, when relocation is performed after rotation of the tire, the ID and the position cannot be matched, that is, the ID is known. However, the position cannot be specified because the position is unknown.

Japanese Examined Patent Publication No. 43-17766 (right column on page 1, lines 20-43, FIG. 1) Japanese Patent Laying-Open No. 2003-226121 (paragraph 0019, FIG. 1)

  By the way, in the first technique, there is a problem that the cost per vehicle becomes high instead of being able to cope with relocation and performing communication satisfactorily. In addition, the second technique has a problem in that it cannot cope with relocation unless it goes to a repair shop or the like instead of reducing the cost per vehicle.

  Accordingly, the main object of the present invention is to provide a transmission / reception auxiliary device and a tire pressure drop alarm device that can reduce the cost mainly per vehicle and can cope with relocation.

  In order to detect the air pressure of each tire of a vehicle having a plurality of tires, the invention according to claim 1 of the present invention that solves the above-mentioned problems is provided with a pressure sensor provided in each tire, and for these pressure sensors. Transmitting means provided respectively, one receiving means for receiving a signal detected by the pressure sensor wirelessly transmitted from these transmitting means on the vehicle body side, and each tire based on the signal received by the receiving means Control means for determining the air pressure state, and notification means for reporting to the driver the air pressure state of the tire based on the determination result output from the control means, the transmission means in the tire pressure drop alarm device, A transmission / reception assisting device for assisting transmission / reception of receiving means, provided at a location outside the vehicle and in the vicinity of the transmitting means. , An external receiving means for receiving a signal wirelessly transmitted from the transmitting means, and a signal which is provided outside the vehicle and in the vicinity of the receiving means and is transmitted by wire from the external receiving means And external transmission means for wirelessly transmitting to the reception means.

  Here, “a place outside the vehicle and in the vicinity of the transmission means” means, for example, a road surface on which each tire of the vehicle is in contact with the ground, or a wall located near each tire (for example, a wall of a garage) Means. Further, “a place outside the vehicle and in the vicinity of the receiving means” means that the receiving means is provided on the bottom of the vehicle body, for example, on the road surface near the receiving means, or the receiving means is in the mirror of the vehicle, for example. Means a wall (for example, a garage wall) located near the mirror.

  According to the first aspect of the present invention, when the positions of the receiving means and transmitting means on the vehicle side do not match the positions of the external transmitting means and external receiving means on the transmission / reception assisting device side, for example, the vehicle travels In this case, the tire air pressure drop alarm device can inform the driver of the tire air pressure drop status as in the conventional art by performing transmission and reception between the transmitting means and the receiving means. Also, when the position of the receiving means and transmitting means on the vehicle side matches the position of the external transmitting means and external receiving means on the transmission / reception assisting device side, for example, when the vehicle stops on the transmission / reception assisting device embedded in the road surface The signals transmitted from the plurality of transmission means on the vehicle side are transmitted to one reception means on the vehicle side via the plurality of external reception means and one external transmission means on the road surface side.

  Here, the ID (identification code) of each external receiving means always indicates the position of the tire of the vehicle because the position of each external receiving means is always fixed. Therefore, for example, even if the left and right tires on the front side of the vehicle are recombined with each other, the ID of the tire and the ID of the external receiving means provided in the vicinity of the tire are transmitted to the control means via the external transmitting means and the receiving means on the vehicle body side. By transmitting, the control means can reset the tire ID and the tire position based on the tire ID and the ID of the external receiving means.

  The invention according to claim 2 is the transmission / reception assisting device according to claim 1, wherein the identification code of each tire is provided based on a signal provided outside the vehicle and transmitted by wire from the external receiving means. And an external control means for matching the position of each tire and outputting the result to the external transmission means.

  According to the second aspect of the invention, the external control means provided outside the vehicle determines the ID of each tire and the position of each tire based on, for example, the ID of each external receiving means and the ID of each tire. Since resetting is performed so as to match, the vehicle body side control device can match the ID of each tire with the position of each tire simply by overwriting the reset data with the previous data. In other words, a special function (a function for resetting the ID of each tire and the position of each tire based on the ID of each external receiving means and the ID of each tire) is added to the control means on the vehicle body side. It is possible to cope with relocation without doing so.

  The invention according to claim 3 is a tire pressure drop alarm device capable of transmitting / receiving to / from the transmission / reception auxiliary device according to claim 1 or 2, wherein the adjusting means adjusts the amount of power supplied to the transmitting means. Is provided.

  According to the third aspect of the present invention, while the vehicle is running, the adjusting means is adjusted so that the amount of electric power supplied to the transmitting means becomes large, so that the transmitting means provided on each tire and the vehicle body side Transmission / reception with the provided receiving means is performed satisfactorily. Further, when the vehicle stops (for example, when the vehicle stops on a transmission / reception auxiliary device embedded in the road surface), the adjustment means is adjusted so that the amount of power supplied to the transmission means becomes small, so that each tire The power consumption of the provided battery will be suppressed. Even if the amount of power supplied to the transmission means is reduced in this way, the signal transmitted from the transmission means is transmitted to the vehicle-side reception means satisfactorily via the road-side external reception means and external transmission means. Is done.

  According to the first aspect of the present invention, since only one receiving means is provided on the vehicle body side, the cost per vehicle can be reduced. In addition, the signal from the transmission means provided on each tire is transmitted to the external reception means having an ID corresponding to the position of each tire or the reception means on the vehicle body side via the external transmission means, so that relocation is supported. It becomes possible.

  According to the second aspect of the present invention, the relationship between the ID of each tire and the position of each tire can be reset by the external control means provided outside the vehicle. It is possible to support relocation without adding a function.

  According to the third aspect of the invention, for example, the amount of electric power can be reduced by the adjusting means when the vehicle is stopped, so that the life of the battery provided in each tire can be extended.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a perspective view showing a tire pressure drop alarm device and a transmission / reception auxiliary device according to the present embodiment, FIG. 2 is a block diagram showing details of the tire pressure drop warning device, and FIG. FIG.

  As shown in FIG. 1, the tire pressure drop alarm device 1 includes four transmission units 2 provided on four tires T of a vehicle M, and one receiving unit provided in a substantially central part (near the driver's seat) of the vehicle body. 3 is mainly provided. As shown in FIG. 2, the transmission unit 2 mainly includes a pressure sensor 21, a memory 22, a CPU 23, a battery 24, an adjustment circuit (adjustment means) 25, a transmission circuit 26, and a transmission antenna 27.

  In FIG. 2, only one of the four transmission units 2 is shown, and the remaining three transmission units 2 have the same structure and are not shown. Further, the transmission circuit 26 and the transmission antenna 27 in the present embodiment correspond to “transmission means” in the claims. Further, in this embodiment, in order to particularly refer to the transmission function of the unit provided on the tire T side, this unit is referred to as a transmission unit 2 and only the transmission function will be described in the following description. The transmission unit 2 has a function of receiving a signal by using the transmission circuit 26 and the transmission antenna 27 for reception. Further, similarly, the reception unit 3 actually has a function of transmitting a signal to the transmission unit 2 by using a reception antenna 31 and a reception circuit 32 described later for transmission.

  The pressure sensor 21 is a sensor for detecting the air pressure of the tire T, and outputs the detected pressure signal to the CPU 23. The memory 22 is a storage means for storing the ID (identification code) of the tire T. The CPU 23 outputs the pressure signal sent from the pressure sensor 21 and the ID of the tire T taken out from the memory 22 to the transmission circuit 26.

  The battery 24 supplies power to the pressure sensor 21, the CPU 23, the transmission circuit 26, and the like. The adjustment circuit 25 adjusts the amount of power supplied from the battery 24 to the transmission circuit 26, and has a switch (not shown) for switching the amount of power inside. This switch may be switched manually or automatically, but in this embodiment, the signal is sent from the receiving unit 3 to the transmitting unit 2 by switching an output switching switch (not shown) provided near the driver's seat. The switch in the adjustment circuit 25 is switched between the high output mode and the low output mode by the CPU 23 of the transmission unit 2.

  The transmission circuit 26 is a circuit that wirelessly transmits data sent from the CPU 23 to the reception unit 3 on the vehicle body side or the external reception unit 5 (see FIG. 1) described later via the transmission antenna 27.

  The receiving unit 3 mainly includes a receiving antenna (receiving means) 31, a receiving circuit (receiving means) 32, a storage device 33, an ECU (control means) 34, and a notifying means 35, and a 12V battery (not shown) provided in the vehicle M. Power is being supplied from. The reception circuit 32 receives a signal wirelessly transmitted from the transmission unit 2 via the reception antenna 31 and outputs the signal to the ECU 34. The storage device 33 stores position information indicating the position of each tire T corresponding to the ID of each tire T, and stores a threshold value of air pressure for notifying the driver of a decrease in air pressure. .

  The ECU 34 calculates a pressure value based on the pressure signal sent from the transmission unit 2 via the reception circuit 32, and sends from the transmission unit 2 which tire T the pressure value indicates. This is determined based on the ID of the coming tire T and the position information extracted from the storage device 33. In addition, the ECU 34 compares the calculated pressure value with the threshold value extracted from the storage device 33, and when it is determined that the pressure value exceeds the threshold value, the determination result is output to the notification means 35. To do. Further, when the position information of the tire T output from the external transmission unit 6 (see FIG. 1) described later is different from the position information stored in the storage device 33, the ECU 34 stores the information in the storage device 33. It has a function of overwriting the stored position information over the position information output from the external transmission unit 6. That is, the ECU 34 has a function of resetting the relationship between the ID of the tire T and the position of the tire T.

  The notification means 35 has a function of reporting the air pressure state of the tire T to the driver based on the determination result output from the ECU 34. Specifically, if the determination result indicates that, for example, the air pressure of the tire T located on the right front side of the vehicle M is equal to or lower than the threshold value, the driver is in front of the right via a lamp, an image, a sound, or the like. The tire T is configured to report that the air pressure of the tire T has decreased.

  Further, as shown in FIG. 1, the transmission / reception assisting device 4 is for assisting transmission / reception between the transmission unit 2 and the receiving unit 3 in the tire pressure drop alarm device 1 and is a parking lot for parking the vehicle M. In the road surface, that is, outside the vehicle M. The transmission / reception auxiliary device 4 includes four external reception units (external reception means) 5 provided in the vicinity of each transmission unit 2 provided in each tire T and one external provided in the vicinity of the reception unit 3 provided in the vehicle body. A transmission unit 6 is mainly provided. The transmission / reception assisting device 4 is supplied with power from a power source (not shown) provided on the road surface side.

  As shown in FIG. 3, the external receiving unit 5 mainly includes an external receiving antenna 51, an external receiving circuit 52, a memory 53, and an external CPU 54. In FIG. 3, only one of the four external transmission units 6 is illustrated, and the remaining three external transmission units 6 have the same structure and are not shown.

  The external receiving antenna 51 is an antenna formed in a loop shape surrounding the tire T (see FIG. 1). The external reception circuit 52 receives a signal from the transmission unit 2 via the external reception antenna 51 and outputs the signal to the external CPU 54. The memory 53 is a storage unit for storing the ID of the external receiving unit 5. The external CPU 54 wire-transmits the pressure signal and tire ID sent from the transmission unit 2 and the ID of the external reception unit 5 taken out from the memory 53 to the external transmission unit 6 via the cable C. Yes.

  The external transmission unit 6 mainly includes an external ECU (external control means) 61, an external transmission circuit (external transmission means) 62, and an external transmission antenna (external transmission means) 63. The external ECU 61 has a function of matching the ID of the tire T with the actual position of the tire T based on a signal output from the external receiving unit 5. Specifically, since the external receiving unit 5 is fixed on the road surface, the ID of the external receiving unit 5 always indicates the actual position of the tire T. Based on the ID, position information that associates the ID of the tire T with the actual position of the tire T is calculated. The external ECU 61 outputs the calculated position information and a pressure signal transmitted from the transmission unit 2 via the external reception unit 5 to the external transmission circuit 62. The external transmission circuit 62 wirelessly transmits the position information and pressure signal output from the external ECU 61 to the receiving unit 3 of the vehicle body via the external transmission antenna 63.

  Next, the operation of the tire pressure drop warning device 1 while the vehicle M is traveling will be described. In the drawings to be referred to, FIG. 4 is a configuration diagram showing the operation of the tire pressure drop alarm device while the vehicle is running.

  As shown in FIG. 4, during traveling of the vehicle M, the pressure signal of the tire T, the ID of the tire T, and the transmission unit 2 of each tire T are sent from the transmission unit 2 of the tire M to the receiving unit 3 provided in the substantially central portion of the vehicle M. Is sent every predetermined time. In the following, the ID of the tire T provided at the front left of the vehicle M is “01”, the ID of the tire T provided at the front right is “02”, the ID of the tire T provided at the rear left is “03”, and the rear right The ID of the provided tire T will be described as “04”. Further, while the vehicle M is traveling, the adjustment circuit 25 shown in FIG. 2 is switched to the high output mode.

  In the receiving unit 3 that has received the signal from the transmitting unit 2 as described above, first, the ECU 34 shown in FIG. 2 calculates a pressure value based on the pressure signal, and which tire T indicates the air pressure of the pressure value. This is determined based on position information extracted from the storage device 33. That is, when the ID of the tire T is “01”, for example, the ECU 34 determines that the pressure signal sent together with the ID “01” indicates the air pressure of the tire T on the left front of the vehicle M. It is supposed to be.

  Further, the ECU 34 compares the calculated pressure value with the threshold value extracted from the storage device 33, and determines whether or not the pressure value exceeds the threshold value. When the ECU 34 determines that the pressure value exceeds the threshold value, the determination result is output to the notification means 35, and the notification means 35 reduces the air pressure of the tire T at which position. For example, the driver can know how much the air pressure of the tire T at which position is reduced by displaying on the monitor.

  Next, operations of the tire pressure drop alarm device 1 and the transmission / reception auxiliary device 4 while the vehicle M is stopped will be described. In the drawings to be referred to, FIG. 5 is a configuration diagram showing the operation of the tire pressure drop alarm device and the transmission / reception auxiliary device while the vehicle is stopped, and (a) is a side view of the tire pressure drop alarm device and the transmission / reception auxiliary device. The side view which shows a state, (b) is a top view which shows the state which looked at the tire air pressure fall alarm apparatus and the transmission / reception auxiliary device from upper direction. FIG. 6 is a block diagram showing the operation of the tire pressure drop alarm device and the transmission / reception auxiliary device when the left front tire and the right front tire of the vehicle are rearranged.

  Initially, with reference to FIG. 5, the inspection work of each tire T is demonstrated. It is assumed that the vehicle M is parked so that each tire T is positioned in each external receiving antenna 51 formed in a loop shape. Further, it is assumed that the adjustment circuit 25 shown in FIG. 2 is initially in the high output mode.

  As shown in FIGS. 5 (a) and 5 (b), when the driver turns on an ignition switch (not shown) before starting the vehicle M, an activation signal for activating the transmission unit 2 is received from the reception unit 3. The data is transmitted directly to the transmission unit 2 or via the transmission / reception auxiliary device 4 embedded in the road surface, and the transmission unit 2 is activated. Next, when the driver switches the output selector switch provided in the driver's seat to the low output mode, the signal is transmitted directly from the receiving unit 3 to the transmitting unit 2 or via the transmission / reception auxiliary device 4 embedded in the road surface. Thus, the amount of power supplied to the transmission circuit 26 (see FIG. 2) in the transmission unit 2 is limited by the adjustment circuit 25 (see FIG. 2).

  When the amount of power is limited in this way, direct transmission from the transmission unit 2 to the reception unit 3 cannot be performed, but a weak output signal skipped from the transmission unit 2 is transmitted to the external reception unit 5 of the transmission / reception auxiliary device 4. This signal is then transmitted to the receiving unit 3 on the vehicle body side via the cable C and the external transmitting unit 6. That is, when checking the air pressure of the tire T when the vehicle M is stopped, the power consumption of the battery 24 (see FIG. 2) in the transmission unit 2 is suppressed.

  Next, operations of the tire pressure drop alarm device 1 and the transmission / reception assisting device 4 when the left front tire T and the right front tire T of the vehicle M are rearranged (relocated) will be described with reference to FIG. It is assumed that the vehicle M is parked so that each tire T is positioned in each external receiving antenna 51 formed in a loop shape, as described above. Further, the position information first stored in the storage device 33 (see FIG. 2) in the receiving unit 3 is information indicating that the ID “01” of the tire T indicates “the left front of the vehicle M” as described above. ID “02” is information indicating “right front of vehicle M” (see FIG. 4). Further, ID “03” is information indicating “left rear of vehicle M”, and ID “04” is information indicating “right rear of vehicle M” (see FIG. 4).

  As illustrated in FIG. 6, when the left front tire T and the right front tire T of the vehicle M are rearranged, the tire T with ID “01” is positioned in front of the vehicle M, and the tire T with ID “02” is the vehicle M. Will be located in front of the left. Then, after the replacement work of the tire T is completed, by turning on the ignition switch, the transmission unit 2 is started as described above, and the pressure signal and the tire T are transmitted from the transmission unit 2 to the external reception unit 5. Send ID.

  In this way, the external receiving unit 5 that has received the pressure signal and the ID of the tire T transmits the ID of the external receiving unit 5 together with these signals to the external transmitting unit 6. That is, as shown in FIG. 6, a pressure signal (not shown), an ID “02” of the tire T, and an ID “FL” of the external receiving unit 5 are transmitted from the external receiving unit 5 on the left front of the vehicle M. Is transmitted, and the pressure signal, the ID “01” of the tire T, and the ID “FR” of the external reception unit 5 are transmitted from the external reception unit 5 on the right front side. Further, the pressure signal, the ID “03” of the tire T, and the ID “RL” of the external receiving unit 5 are transmitted from the external receiving unit 5 at the left rear of the vehicle M, and from the external receiving unit 5 at the right rear. The pressure signal, the ID “04” of the tire T, and the ID “RR” of the external receiving unit 5 are transmitted.

  Then, the external transmission unit 6 calculates position information that associates the ID of the tire T with the actual position of the tire T based on the ID of the external reception unit 5 described above. That is, the external transmission unit 6 determines that the tire T having an ID of “02” is positioned in front of the left side of the vehicle M based on the ID “FL” of the external reception unit 5 on the left front, for example. Information “ID” indicating “left front of vehicle M” is calculated as position information. As a result, the position information newly calculated after the rearrangement of the tire T is such that the ID “01” of the tire T is the front right of the vehicle M, the ID “02” is the front left of the vehicle M, and the ID “03” is the rear left of the vehicle M. , ID “04” is information indicating the right rear of the vehicle M, and is different from the position information (see FIG. 4) stored in the storage device 33 in the receiving unit 3.

  Then, the external transmission unit 6 that has calculated the new position information in this way transmits the position information, the pressure signal, and the ID of the tire T to the reception unit 3 on the vehicle body side. When receiving the new position information from the external transmission unit 6, the receiving unit 3 first compares the new position information with the position information stored in the storage device 33 (see FIG. 4). As a result of this comparison, if the new position information and the position information stored in the storage device 33 are different, the position information stored in the storage device 33 is overwritten with the new position information, and the position information is reset. It becomes. Then, after the position information is reset in this way, the receiving unit 3 can accurately recognize the position of the tire T based on the new position information.

According to the above, the following effects can be obtained in the present embodiment.
Since only one receiving antenna 31 is provided on the vehicle body side, the cost per vehicle can be reduced. Further, the signal from the transmission unit 2 provided in each tire T is obtained from the position information based on the external reception unit 5 having an ID corresponding to the position of each tire T and each signal output from the external reception unit 5. Since it transmits to the receiving unit 3 on the vehicle body side via the external transmission unit 6 to be calculated, it becomes possible to cope with relocation.

Since the relationship between the ID of each tire T and the position of each tire T can be reset by the external ECU 61 provided outside the vehicle M, a special function (based on the ID of the external receiving unit 5) is provided to the ECU 34 on the vehicle body side. Thus, relocation can be handled without adding a function for calculating position information.
Since the amount of electric power can be reduced by the adjustment circuit 25 when the vehicle M is stopped, the life of the battery 24 provided in each tire T can be extended.
If the transmission / reception assisting device 4 can be shared by external facilities (gas station, dealer service, etc.), it will be socially effective.

As mentioned above, this invention is implemented in various forms, without being limited to the said embodiment.
In the present embodiment, the transmission / reception assisting device 4 is embedded in the road surface. However, the present invention is not limited to this. For example, the transmission / reception assisting device 4 may be installed on the road surface. Further, the transmission / reception assisting device 4 may be provided with a non-contact charging device for charging each battery 24 provided on each tire T in a non-contact manner. Furthermore, the transmission / reception assisting device 4 may be installed in any place such as a factory line, a dealer, or a general household.

  In the present embodiment, the adjustment circuit 25 is switched between the high output mode and the low output mode by an output changeover switch (not shown) provided in the vicinity of the driver's seat, but the present invention is not limited to this, for example, a vehicle speed sensor The adjustment circuit 25 may be automatically switched in accordance with the vehicle speed detected in step 1.

  In the present embodiment, the adjustment circuit 25 is provided only in the transmission unit 2, but the present invention is not limited to this. For example, by providing the adjustment circuit 25 in the reception unit 3, the vehicle M can be skipped from the reception unit 3 when the vehicle M stops. You may make it weaken an electromagnetic wave. According to this, since the power consumption of the 12V battery can be suppressed when the vehicle M is stopped, the life of the 12V battery can be extended.

  In the present embodiment, the external receiving unit 5 is fixed to the road surface, but the present invention is not limited to this, and the external receiving unit 5 may be configured to be movable back and forth and left and right. According to this, the one transmission / reception auxiliary | assistance apparatus 4 can be shared with respect to the vehicle from which a wheel base differs, and the vehicle from which the space | interval of a right-and-left tire differs.

It is a perspective view which shows the tire air pressure fall warning apparatus and transmission / reception auxiliary device which concern on this embodiment. It is a block diagram which shows the detail of a tire air pressure fall warning apparatus. It is a block diagram which shows the detail of a transmission / reception auxiliary | assistance apparatus. It is a block diagram which shows operation | movement of the tire air pressure fall warning apparatus in driving | running | working of a vehicle. It is a block diagram which shows operation | movement of the tire air pressure fall warning apparatus and transmission / reception auxiliary | assistance apparatus in the time of a vehicle stop, (a) is a side view which shows the state which looked at the tire air pressure fall alarm apparatus and transmission / reception assistance apparatus from the side, (b) ) Is a top view showing a state in which the tire pressure drop alarm device and the transmission / reception auxiliary device are viewed from above. It is a block diagram which shows operation | movement of the tire air pressure fall warning apparatus and transmission / reception auxiliary | assistance apparatus at the time of rearranging the front left tire and the front right tire of a vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tire pressure fall warning apparatus 2 Transmission unit 21 Pressure sensor 22 Memory 23 CPU
24 battery 25 adjustment circuit 26 transmission circuit 27 transmission antenna 3 reception unit 31 reception antenna 32 reception circuit 33 storage device 34 ECU
35 Notification means 4 Transmission / reception auxiliary device 5 External reception unit 51 External reception antenna 52 External reception circuit 53 Memory 54 External CPU
6 External transmission unit 61 External ECU
62 External transmission circuit 63 External transmission antenna M Vehicle T Tire C Cable

Claims (3)

In order to detect the air pressure of each tire of a vehicle having a plurality of tires, a pressure sensor provided on each tire;
Transmission means provided for each of these pressure sensors;
One receiving means for receiving a signal detected by the pressure sensor wirelessly transmitted from these transmitting means on the vehicle body side;
Control means for determining the air pressure state of each tire based on the signal received by the receiving means;
An assisting means for notifying the driver of the tire air pressure state based on the determination result output from the control means, for assisting transmission / reception of the transmitting means and the receiving means in a tire pressure drop alarm device. A transmission / reception auxiliary device,
An external receiving means for receiving a signal wirelessly transmitted from the transmitting means, provided at a location outside the vehicle and in the vicinity of the transmitting means;
An external transmission unit that is provided outside the vehicle and in the vicinity of the reception unit, and that wirelessly transmits a signal transmitted by wire from the external reception unit to the reception unit. A transmission / reception auxiliary device. The transmission / reception assisting device according to claim 1,
Based on a signal provided outside the vehicle and transmitted by wire from the external receiving means, an external code for matching the identification code of each tire with the position of each tire and outputting the result to the external transmitting means A transmission / reception assisting device comprising a control means. A tire pressure drop alarm device capable of transmitting / receiving with the transmission / reception auxiliary device according to claim 1 or 2,
An apparatus for alarming a decrease in tire air pressure, comprising adjusting means for adjusting the amount of electric power supplied to the transmitting means.

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